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Aging, Neuropsychology, and Cognition:A Journal on Normal and DysfunctionalDevelopmentPublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/nanc20

The role of warnings in youngerand older adults’ retrieval-inducedforgettingJodi Pricea, Lauren W. Jonesa & Michael L. Muellera

a Department of Psychology, The University of Alabama inHuntsville, Huntsville, AL, USAPublished online: 06 Mar 2014.

To cite this article: Jodi Price, Lauren W. Jones & Michael L. Mueller (2015) The role of warningsin younger and older adults’ retrieval-induced forgetting, Aging, Neuropsychology, and Cognition: AJournal on Normal and Dysfunctional Development, 22:1, 1-24, DOI: 10.1080/13825585.2014.888390

To link to this article: http://dx.doi.org/10.1080/13825585.2014.888390

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The role of warnings in younger and older adults’ retrieval-inducedforgetting

Jodi Price*, Lauren W. Jones and Michael L. Mueller

Department of Psychology, The University of Alabama in Huntsville, Huntsville, AL, USA

(Received 29 May 2012; accepted 23 January 2014)

Retrieval-induced forgetting (RIF) is a phenomenon wherein practicing recalling someitems impairs recall of semantically related, unpracticed items. Two experimentsexamined whether explicitly warning older (Experiment 1) and younger adults(Experiments 1 and 2) about RIF at different times during two exposures to theretrieval-practice paradigm would affect participants’ forgetting. Participants in bothexperiments were either warned before encoding, retrieval-practice, recall, or not at all.The warning was combined with integration instructions in Experiment 2. Warningsdid not reduce forgetting in either age group in Experiment 1. Forgetting increasedacross exposures in most cases and older adults experienced more forgetting than didyounger adults. Combining integration instructions with the warning also did notreduce younger adults’ forgetting relative to baseline conditions in Experiment 2.Results indicate that both younger and older adults are susceptible to retrieval-inducedforgetting and that raising awareness of the phenomenon increases rather thandecreases forgetting rates.

Keywords: retrieval-induced forgetting; aging; warnings; associative learning

Retrieval-induced forgetting is a memory phenomenon, wherein practicing recalling somestudied items enhances recall of those items while impeding access to semanticallyrelated, unpracticed items (Anderson, Bjork, & Bjork, 1994). This form of forgettinghas been said to reflect either inhibitory or noninhibitory mechanisms, which are thoughtto occur automatically without intentional processing (Anderson, 2003, 2005; Andersonet al., 1994; Hogge, Adam, & Collette, 2008; Storm & Levy, 2012; Williams & Zacks,2001). Thus, it is unknown whether participants become aware of their forgetting andwhat impact raising younger and older adults’ awareness of the RIF phenomenon mighthave on their tendency to forget. We report two experiments in which we examinedwhether explicitly warning participants about retrieval-induced forgetting would decreasetheir forgetting.

RIF is typically assessed using the retrieval-practice paradigm, which consists ofencoding, retrieval-practice, and recall phases (Anderson et al., 1994). During the studyphase, participants study several category cue–exemplar pairs (e.g., FRUIT – Orange) insuccession. Participants then practice recalling a subset of the encoded items by complet-ing cue–stem pairs in which one or two letters of an exemplar are presented (e.g., FRUIT– O_____). Only half of the exemplar pairs from half of the total number of cues are givenfor practice, and these pairs are typically presented at least three times throughout thepractice phase (Anderson et al., 1994). After a retention interval, participants complete acued-recall test on all the items.

*Corresponding author. Email: jodi.price@uah.edu

Aging, Neuropsychology, and Cognition, 2015Vol. 22, No. 1, 1–24, http://dx.doi.org/10.1080/13825585.2014.888390

© 2014 Taylor & Francis

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There are three types of items and two calculations commonly associated withretrieval-induced forgetting and the retrieval-practice paradigm. Items practiced duringthe retrieval-practice phase are strengthened items (Rp+). Items that are members of thesame categories as strengthened items, but are not practiced, are non-strengthened items(Rp−). Finally, items that are in categories where none of the exemplars are presentedfor practice are called unpracticed items (Nrp). Facilitation effects are calculated bysubtracting an individual’s mean recall of unpracticed items from strengthened items(i.e., [Rp+] – [Nrp]), with positive numbers reflecting facilitation. Impairment effects arecalculated by subtracting an individual’s mean recall of unpracticed items from non-strengthened items (i.e., [Rp−] – [Nrp]), with negative numbers reflecting more forget-ting (Anderson et al., 1994). Impairment effects are the key focus in the retrieval-practice paradigm.

Retrieval-induced forgetting mechanisms

Much of the research utilizing the retrieval-practice paradigm has focused on identifyingwhich mechanisms underlie RIF and factors that may increase or decrease participants’rates of forgetting. Competing accounts suggest that either inhibitory or noninhibitorymechanisms drive RIF (Anderson & Spellman, 1995; Anderson et al., 1994; Williams &Zacks, 2001). The inhibitory account suggests that inhibition occurs during retrieval-practice, which serves to reduce competition by inhibiting the Rp− items, thereby facil-itating the recollection of Rp+ items (Anderson, 2003; Anderson et al., 1994; Storm &Levy, 2012). The noninhibitory account (e.g., interference or blocking) proposes that asretrieval-practice strengthens Rp+ items it can simultaneously interfere with or stealactivation away from the Rp− items associated with the same retrieval cues, thus makingRp− items less likely to be recalled (Anderson & Bjork, 1994; Anderson et al., 1994;Storm & Levy, 2012; Williams & Zacks, 2001). Supporters of both accounts agree thatrecall of Rp− items is impeded, but disagree about when forgetting occurs and whatcauses it. The inhibitory account suggests that forgetting occurs during retrieval-practice,whereas the noninhibitory account suggests that forgetting occurs during recall (Andersonet al., 1994).

Aging and retrieval-induced forgetting

Given the focus on inhibitory mechanisms in RIF, researchers have examined whetherthere are age differences in this paradigm. Age-related declines in inhibitory control arewell documented (for a review, see Hasher & Zacks, 1988). However, a number ofstudies have provided evidence that a distinction must be made between intentional (i.e.,effortful) and unintentional (i.e., automatic) inhibitory processes (Anderson, 2005;Andreś, Guerrini, Phillips, & Perfect, 2008; Conway & Fthenaki, 2003; Hogge et al.,2008). Age-related deficits are frequently observed in tasks that require intentionalinhibitory processes, such as in Stroop (Hartman & Hasher, 1991; Spieler, Balota, &Faust, 1996) and directed forgetting tasks (Titz & Verhaeghen, 2010; Zacks, Radvansky,& Hasher, 1996). In contrast, a growing body of research points to the absence of agedifferences in tasks that tap unintentional inhibitory control (Aslan, Bauml, & Pastotter,2007; Hogge et al., 2008). In particular, studies have found that both younger and olderadults are susceptible to RIF (Aslan et al., 2007; Gómez-Ariza, Pelegrina, Lechuga,Suárez, & Bajo, 2009), suggesting that the mechanism(s) underlying the forgetting mustbe non-effortful. However, Hogge et al. (2008) observed RIF in younger and older

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adults for tasks that tapped both automatic and intentional memory processes, suggest-ing that forgetting may not always be automatic. If forgetting does not occur automa-tically, then it might be possible for individuals to counteract their RIF if they wereaware of the phenomenon.

Warnings

Warnings have been used extensively across many domains to address encoding andretrieval issues. For example, Pelegrina, Bajo, and Justicia (2000) explicitly warnedparticipants that people often study concrete and abstract words differently and are lesslikely to recall abstract than concrete words. They found that the warning causedparticipants to alter their study time of each item type in order to equalize recall ofconcrete and abstract words. This finding suggests that giving participants explicit warn-ings regarding encoding and recall issues may be sufficient to change recall rates from onetime to another.

Another domain in which researchers have examined the impact of warnings is thefalse memory literature. Multiple studies provide evidence that warnings can decreaseparticipants’ memory failures (e.g., Echterhoff, Hirst, & Hussy, 2005; Gallo, Roberts, &Seamon, 1997; Neuschatz, Benoit, & Payne, 2003). For example, warnings have provento be effective in reducing errors on eyewitness memory tests (Chambers & Zaragoza,2001; Echterhoff et al., 2005) as well as participants’ tendency to falsely recall non-presented critical lures (e.g., sleep) after studying semantic associates of the lure (e.g.,awake, rest, bed) in the Deese-Roediger-McDermott (Deese, 1959; Roediger &McDermott, 1995) false memory paradigm (Gallo et al., 1997; McDermott & Roediger,1998; Neuschatz et al., 2003; Westerberg & Marsolek, 2006). However, the warnings onlyreduced false memories when they were presented before the encoding phase; whenwarnings were presented after encoding, but before testing, they did not reduce falsememories (e.g., McDermott & Roediger, 1998; Neuschatz et al., 2003; Westerberg &Marsolek, 2006). Thus, the effectiveness of warnings may depend on when the warningsare provided.

Although warnings have been found to remedy memory issues in other domains, thereis some evidence that individuals might become aware of their RIF without beingexplicitly warned about the phenomenon. Carroll, Campbell-Ratcliffe, Murnane, andPerfect (2007) found that participants who experienced some forgetting in the retrieval-practice paradigm were mildly aware that practicing retrieval of some items had adetrimental effect on the recall of other related items, as reflected by their lower judg-ments of learning (i.e., estimates of likelihood of recalling items) for Rp− (as compared toRp+ or Nrp) items. However, Carroll and colleagues did not use the standard cue–exemplar pairs when assessing RIF. They instead used case studies of schizophreniaand autism from psychology textbooks for which encoding and retrieval techniquesmight have been slightly different than those used with cue–exemplar pairs. Thus, itremains unknown whether participants become aware of their forgetting if traditionalstimuli are used. Moreover, because all prior research examining retrieval-induced for-getting has exposed participants to the retrieval-practice paradigm (encoding – retrieval-practice – cued-recall test) one time, it is unknown whether they become aware of theirforgetting or if they are able to do anything to reduce forgetting if exposed to the retrieval-practice paradigm twice. Another unanswered question is when participants could beexpected to become aware of their forgetting.

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Hertzog et al. (2008; see also Hertzog et al., 2009, and Price, Hertzog, & Dunlosky,2008) examined whether individuals would learn about the effects of different encodingstrategies (rote repetition or interactive imagery) on later recall when studying pairedassociates across two study–test sessions. Of interest was when individuals becameaware and updated their knowledge about which strategy would maximize recallperformance (see Dunlosky & Hertzog, 2000, for a discussion of the knowledgeupdating process). Hertzog et al. (2008) found that knowledge updating for strategyeffectiveness critically depends on recall test experience. Such findings, when extendedto the question of participants’ awareness of RIF, suggest that individuals may notbecome aware of impairment effects until after they have experienced problems recallingRp− items.

If recall experience alone is sufficient to raise participants’ awareness of retrieval-induced forgetting, then we would expect participants to show less impairment the secondtime they are exposed to the retrieval-practice paradigm than that shown after the firstexposure. However, an explicit warning about RIF might be required to raise participants’awareness of the memory phenomenon. Moreover, the timing of the warning mightimpact whether it has any impact on participants’ retrieval-induced forgetting(McDermott & Roediger, 1998; Neuschatz et al., 2003; Westerberg & Marsolek, 2006).Thus, the present studies examined whether individuals become aware of the tendency toforget the Rp− items by exposing participants to the retrieval-practice paradigm two times,henceforth referred to as Part 1 and Part 2. Control (i.e., unwarned) conditions as well asconditions in which participants were explicitly warned about RIF before either theencoding, retrieval-practice, or the recall test phases were included in each experiment.Of interest was whether participants’ awareness of the phenomenon would affecttheir RIF.

Experiment 1

This experiment was designed to test if differently timed warnings would impact youngerand older adults’ RIF. A baseline condition was used simply as a control group.Participants in three experimental warning conditions received a warning about RIFboth times they were exposed to the retrieval-practice paradigm, either before encodingbegan, between encoding and the retrieval-practice phase, or after the Part 1 distractor taskbefore the recall phase.

Younger and older adults were expected to experience similar levels of impairment inthe baseline condition, given prior research showing no age differences in the retrieval-practice paradigm (e.g., Aslan et al., 2007; Gómez-Ariza et al., 2009; Hogge et al., 2008).We hypothesized that if younger and older adults are able to benefit from the warning andengage in intentional encoding or retrieval processes to counteract their forgetting, thenwarned participants should have lower rates of impairment than those in the baselinecondition. We expected the warnings to impact younger and older adults’ impairment in asimilar manner. However, even with warnings, it remained possible that older adults’slower speed of processing (Salthouse, 1996) or reduced executive control (Salthouse &Babcock, 1991) could decrease their ability to design and use a strategy (i.e., a productionor utilization deficiency; Dunlosky, Hertzog, & Powell-Moman, 2005) within the timeconstraints of the experiment to effectively eliminate their forgetting. These deficits couldyield age differences in the rates of impairment or in when warnings should be presentedto allow older adults sufficient time to implement a strategy for overcoming retrieval-

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induced forgetting. The present experiment included the differently timed warnings toexamine these issues.

Method

Participants

Participants were 107 undergraduate students (18–25 years of age; M age = 19.25,standard deviation (SD) = 1.31; M years of education = 14.36, SD = 0.82; 66% Female)and 100 older adults (60–85 years of age; M age = 71.00, SD = 6.10; M years ofeducation = 16.85, SD = 3.01; 63% Female).1 Younger adults were enrolled in introduc-tory psychology courses at The University of Alabama in Huntsville and received partialcourse credit for participating. Older adults were recruited from the Huntsville, Alabamaarea and were paid $10 for participating.2 All APA ethical guidelines were followed.

Random assignment to conditions yielded 27 younger and 25 older adults in thebaseline condition, 27 younger and 27 older adults in the pre-encoding warning condition,27 younger and 22 older adults in the pre-retrieval-practice warning condition, and 26younger and 26 older participants in the pre-recall warning condition.

Design and Materials

A 2 (Age group: younger, older) × 2 (Part: 1, 2) × 3 (Item type: Rp+, Rp−, Nrp) × 4(Warning: baseline, pre-encoding, pre-retrieval-practice, pre-recall) mixed factorial designwas used with repeated measures for Part and Item type, and Warning manipulatedbetween subjects. The dependent measures in this study were the recall accuracy of allitem types, with these values used to calculate facilitation and impairment effects.

A total of 112 category cue–exemplar pairs were chosen from Battig and Montague’s(1969) word norms. Ninety-six of the pairs, representing 12 categories (Animals,Buildings, Distance, Earth, Fuels, Insects, Office, Professions, Reading, Speech, Tools,and Trees), were used as experimental stimuli, while 16 pairs from four other categories(Colors, Elements, Fruits, and Science) were used as fillers at the beginning and end ofeach study phase to address primacy and recency effects. Items were chosen beginningwith those of the highest associative rank and continuing until eight words for eachcategory were selected such that the categories were constructed with words of similarassociation to the category cue (mean ranks range 4.88–5.63). All items within a categoryhad unique first letters and were equally likely to be assigned as Rp+, Rp−, or Nrp. Itemswere counterbalanced across categories and within each part, but not across participantsbecause of the need to present the same materials to groups of up to six people. Thecategories were divided so that half appeared in each part, with similar mean ranks foreach part (Part 1: 5.30, SD = 0.30; Part 2: 5.43, SD = 0.29). Each part contained eightfiller pairs and 48 experimental pairs. All phases of the retrieval-practice paradigm and thedistractor tasks were presented via PowerPoint. Slides contained the stimuli in 62-pointfont black text on a white background projected on a screen.

Distractor tasks were used between each retrieval-practice phase and the recall test.Number-based tasks were selected so as to not interfere with the word-based criteriontask. The WAIS-III Digit Span Task (Wechsler, 1997), and the Multidimensional AptitudeBattery Digit Symbol Substitution Task (Jackson, 1984) were used in Part 1 and Part 2,respectively. Each task required 10 min to complete.

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A post-task questionnaire was created in-house to assess how participants encoded andattempted to remember the category cue–exemplar word pairs. This questionnaire askedparticipants if and how they changed their methods of learning, remembering, andrecalling items from Part 1 to Part 2, and whether they realized that they were experien-cing RIF. A final questionnaire collected participants’ demographic information.Participants received answer booklets in which to write their answers for the criteriontask before the Part 1 encoding phase. The booklets were collected before the participantswere debriefed.

Procedure

Experimental sessions containing up to six individuals were conducted, where everyperson in that session was in the same age group and assigned to the same condition.Participants within each age group were randomly assigned to one of the four warningconditions (i.e., baseline, pre-encoding, pre-retrieval-practice, or pre-recall) before theexperiment began. Participants in the warning conditions were read a description ofwhat RIF is at condition-specific times (i.e., either pre-encoding, pre-retrieval-practice,or pre-recall) both times they were exposed to the retrieval-practice paradigm (seeAppendix 1 for the warning script). The warning was provided in both parts so that thetime required in and between each phase of the retrieval-practice paradigm was equatedacross both exposures to the paradigm. After participants received the warning, they thenanswered a manipulation check question in which they were shown a list of the three itemtypes (Rp+, Rp−, Nrp) and asked which item type is most likely to be forgotten. They hadto answer the question correctly (i.e., Rp−) before moving on to the next phase.3

Informed consent was collected before the experiment commenced. During the encod-ing phase, participants were presented with 48 category cue–exemplar pairs (e.g., FRUIT– Orange), each 5 s apart with a 1 s interstimulus interval (+) between the word pairs.Four filler category cue–exemplar pairs were presented at the beginning and end of eachencoding phase to control for primacy and recency effects. In the retrieval-practice phase,participants were given half of the exemplars from half of the categories, three times each,in a random order. These were presented as category cues plus a one-letter stem for theexemplar (i.e., FRUIT – O_____). Participants were given 10 s to complete each stem intheir booklet with a word learned during the encoding phase.

After completing the retrieval-practice phase, participants were given the Digit SpanTask (Wechsler, 1997) to distract them for 10 min. Participants viewed sequences ofnumbers ranging from two to nine digits at a time and were asked to write those numbersbackward from memory (e.g., if shown 2–7, they would write 7–2 in their booklets). Eachdigit was presented for 1 s with a 1 s blank slide between digits to indicate that the digitshad changed. The strings were presented in an ascending order and participants wereallotted 2 s per digit to recall the sequences.4

Once participants finished the Digit Span Task, they completed a surprise cued-recalltest. Participants were presented with each category cue on the screen as well as on acorresponding page in their test booklets and asked to recall all the words they couldremember from that category by writing the words under the category name in theirbooklets in any order. After 30 s elapsed, participants were instructed to turn the page andthe next category cue was presented.5 This process continued until all six categories hadbeen presented for recall. After completing the Part 1 recall test, participants in allconditions counted backward by threes from the number 978 for 2 min and then wrote

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down their final number before beginning the Part 2 encoding phase. This served as adistractor task between the two exposures to the retrieval-practice paradigm.

Part 2 utilized the same procedure as that of Part 1. However, new category cue–exemplarpairs and a different distractor task were used. Participants completed the Digit SymbolSubstitution Task (Jackson, 1984) as the Part 2 distractor task, which required matchingsymbols and numbers for 10 min. Participants then completed the Part 2 recall test, post-taskquestionnaire, and the demographics form before being debriefed and released.

Results

Retrieval-practice

A 2 × 2 × 4 (Age group × Part × Warning) analysis of variance (ANOVA) with repeatedmeasures for Part revealed a main effect of Part because accuracy increased across time asparticipants gained familiarity with the paradigm, F(1, 200) = 73.98, p < 0.001, η2p = 0.27(see Table 1). Participants recalled, on average, 68.6% and 79.4% of the 36 category cue–exemplar word pairs in Part 1 and in Part 2, respectively. There was also a marginallysignificant effect of Warning due to the pre-recall warning condition having slightly loweraccuracy than the other three conditions, F(3, 200) = 2.62, p = 0.052, η2p = 0.04. Asignificant Part × Age group interaction was also observed, F(1, 200) = 9.80, p < 0.01, η2p= 0.05, due to younger adults having lower performance than older adults in Part 1(younger M = 24.32, SE = 0.32; older M = 25.05, SE = 0.72), but then showing greaterimprovement than older adults in Part 2 (younger M = 29.66, SE = 0.61; older M = 27.54,SE = 0.63).

Facilitation effects

Facilitation is manifested by higher recall of Rp+ items than Nrp items (see Table 2).A 2 × 2 × 2 × 4 (Age group × Part × Item type × Warning) ANOVA with repeated

Table 1. Retrieval-Practice means for Experiment 1 as a function of age group, warning conditionand part.

Part 1 Part 2

Condition M (SE) M (SE)

BaselineYounger 72.90 (1.38) 87.02 (1.21)Older 70.88 (1.44) 77.22 (1.26)

Pre-encodingYounger 69.56 (1.38) 82.92 (1.21)Older 69.03 (1.38) 75.51 (1.21)

Pre-retrieval-practiceYounger 69.55 (1.38) 81.69 (1.21)Older 72.83 (1.50) 79.95 (1.31)

Pre-recallYounger 58.23 (1.41) 77.88 (1.23)Older 65.60 (1.41) 73.29 (1.23)

Note: Table values are mean percentages, which were calculated by taking the mean number of items recalledduring retrieval-practice and dividing it by the total possible number of words for the retrieval-practice phase(36); standard errors are presented in the parentheses.

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measures for Part and Item type indicated that participants recalled Rp+ items at a higherrate than Nrp items (M = 71%, SE = 1.40 versus M = 50%, SE = 0.90, respectively),which yielded a main effect of Item type, F(1, 200) = 370.80, p < 0.001, η2p = 0.65 (seeFigure 1). The three-way interaction of Age group × Part × Item type was alsosignificant, F(1, 200) = 10.23, p < 0.01, η2p = 0.05, due to younger adults showingincreased facilitation across parts (Part 1: M = 20.30, SE = 2.10; Part 2: M = 23.80,SE = 1.65), and older adults a decrease across parts (Part 1: M = 26.80, SE = 2.15; Part2: M = 15.80, SE = 1.65). There were no differences in facilitation as a function ofWarning, F < 1.

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Baseline Pre-encoding Pre-practice Pre-recall

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Figure 1. Mean facilitation effects for Part 1 and Part 2 as a function of age group and warningcondition in Experiment 1.

Table 2. Mean recall percentages for each item type as a function of age group, warning condition,and part in Experiment 1.

Part 1 Part 2

Condition Rp+ Rp− Nrp Rp+ Rp− Nrp

BaselineYounger 68 (6) 44 (3) 49 (3) 81 (4) 39 (4) 52 (3)Older 71 (6) 38 (3) 44 (3) 68 (4) 39 (4) 52 (3)

Pre-encodingYounger 69 (6) 33 (3) 45 (3) 77 (4) 41 (4) 51 (3)Older 81 (6) 31 (3) 48 (3) 71 (4) 40 (4) 56 (3)

Pre-retrieval-practiceYounger 64 (6) 44 (3) 44 (3) 74 (4) 43 (4) 52 (3)Older 67 (6) 27 (3) 44 (3) 76 (4) 42 (4) 55 (3)

Pre-recallYounger 63 (6) 38 (3) 45 (3) 70 (4) 41 (4) 52 (3)Older 74 (6) 38 (3) 50 (3) 68 (4) 44 (4) 57 (3)

OverallYounger 66 (3) 40 (3) 46 (1) 75 (2) 41 (1) 51 (1)Older 73 (3) 34 (2) 47 (1) 71 (2) 41 (2) 55 (2)

Note: Table values are mean recall and standard errors (in parentheses) associated with each item type, separatedby condition and part; Item types are abbreviated as follows: Rp+ = strengthened items; Rp− = non-strengtheneditems; Nrp = unpracticed items; Baseline condition = participants in the control condition who were not exposedto any experimental manipulation; Pre-encoding = participants warned before they began the Part 1 encodingphase and again before Part 2; Pre-retrieval-practice = participants warned before the retrieval-practice phase ineach part; Pre-recall = participants warned before the recall phase in each part.

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Impairment effects

Impairment effects are reflected by higher recall of Nrp than Rp− items.6 A 2 × 2 × 2 × 4(Age group × Part × Item type × Warning) ANOVA with repeated measures for Part andItem type yielded a main effect of Item type, F(1, 200) = 209.10, p < 0.001, η2p = 0.51,given that participants recalled Rp− items at a lower level than Nrp items (M = 39%,SE = 1.00 versus M = 50%, SE = 0.90, respectively). There was also a significant Itemtype × Age group interaction as a result of younger adults having lower rates of impair-ment than older adults, (M = 8%, SE = 1.30 versus M = 13%, SE = 1.35, respectively),F(1, 200) = 12.54, p < 0.001, η2p = 0.06.

The main effect of Item type and therefore impairment effects were present whenanalyzed across parts, as well as when analyzed separately for Part 1, F(1, 200) = 93.79,p < 0.001, η2p = 0.32, and Part 2, F(1, 200) = 129.00, p < 0.001, η2p = 0.39. However,only in Part 1 were significant interactions observed. As may be seen in Figure 2, theItem type × Warning interaction, F(3, 200) = 3.75, p < 0.05, η2p = 0.05, and Itemtype × Age group × Warning interaction, F(1, 200) = 209.10, p < 0.001, η2p = 0.51,reflected the tendency for there to be lower rates of impairment in the baseline conditionthan in the warned conditions, when collapsing across age groups, but for older adultsto have significantly higher levels of impairment than younger adults. However, posthoc analyses indicated that the significant three-way interaction in Part 1 was driven byage differences observed for those warned before retrieval-practice, F(1, 47) = 4.96,p < 0.05, η2p = 0.10, given that no other age differences were observed in the otherconditions despite post hoc analyses indicating that participants within each warningcondition experienced significant impairment effects in both parts.

Post-task questionnaire responses

Chi-square analyses were run to assess whether post-task questionnaire responses differedas a function of warning or age. Participants were given definitions of the various types ofitems and phases within the retrieval-practice paradigm before they answered questions sothey would know what the various terms meant. Both age groups reported trying to link(i.e., integrate) the words during the encoding phase (91%, collapsing across age groups).However, when examined separately for each age group, 99% of younger adults and only82% of older adults reported trying to integrate items, which yielded a significantdifference, χ2(2, N = 204) = 18.72, p < 0.001. Both age groups said they recalled someitem types at a higher rate than others (73%, collapsing across age groups). When asked torank order which items they recalled at the highest and lowest rates, both age groups

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Figure 2. Mean impairment effects for Part 1 and Part 2 as a function of age group and warningcondition in Experiment 1.

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reported that Rp+ items were recalled the most, Rp− the least, with Nrp items falling inthe middle, with no significant age differences in rankings. However, older adults weresignificantly more likely than younger adults to report that they felt as if they studied morewords than they were able to recall (92% of older adults versus 75% of younger adults), χ2

(1, N = 205) = 10.53, p < 0.01.On average, both age groups reported that it was easier to recall Rp+ words than

words that were not practiced (83%, collapsing across age groups). However, agedifferences were found when participants were asked to indicate which types ofwords, if any, were more difficult to recall as a result of practicing some of thewords. The largest percentage of younger adults (34%) said that Rp+ items interferedwith their ability to recall Rp− items, whereas the largest percentage of older adults(39%) reported that Rp+ items interfered with recalling both Rp− and Nrp items, χ2(3,N = 199) = 27.76, p < 0.001. Collapsing across age groups, 46% of participants saidthey first noticed problems recalling words during the Part 1 recall test. However, whenasked whether they then altered how they approached Part 2 encoding (70%), retrieval-practice (89%), or cued-recall (92%), most participants in both age groups said theyhad not.

Discussion

Experiment 1 examined whether participants in the baseline condition would becomeaware of their forgetting and whether differently timed warnings would impact youngerand older adults’ RIF across parts. We were optimistic that warnings might provebeneficial in addressing RIF, given their history of addressing encoding and retrievalissues in other domains (McDermott & Roediger, 1998; Neuschatz et al., 2003;Westerberg & Marsolek, 2006). However, collapsing across age groups and parts, theresults indicated higher rates of impairment for warned participants than for baselineparticipants. This suggests that awareness of the paradigm increases rather than decreasesRIF. This notion is supported not only by the fact that those in the warning conditions hadhigher rates of impairment than baseline participants in Part 1, but also by the finding thatonce those in the baseline condition gained exposure to the paradigm, their rates ofimpairment were as high as those in the warned conditions in Part 2.

Of additional interest is the finding that in both parts, older adults had higher rates ofimpairment than younger adults in all but the baseline condition. Given that prior studieshave found no age differences in the retrieval-practice paradigm (e.g., Aslan et al., 2007;Gómez-Ariza et al., 2009; Hogge et al., 2008), it is interesting that levels of impairmentfor younger and older adults were only similar in the baseline condition. Nonetheless, itseems unlikely that the warnings were responsible for the observed age differences inimpairment. If raising awareness was the basis for the observed age differences, then agedifferences should have been found for all warning conditions in Part 1 and all fourconditions in Part 2 once the baseline participants became familiar with the paradigm. Thefact that neither of these happened and the age differences in impairment only reachedsignificance for those warned before retrieval-practice in Part 1 points to another possi-bility, namely that the warnings served to increase participants’ cognitive load by increas-ing the attentional demands of the task.

From this perspective, the attentional demands of the task may have increased with thewarning, either subjectively or objectively, depending on how participants interpreted andattempted to respond to the warning. The fact that older adults reported more difficultyrecalling items, but fewer attempts to integrate the items than younger adults is consistent

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with the notion that the task was more demanding for older than younger adults. If olderadults did experience greater cognitive load than younger adults did as a result of thewarning, then this could account for why younger adults’ rates of facilitation increasedacross exposures to the retrieval-practice paradigm, whereas those of older adultsdecreased. In essence, the warning instructions may have created the equivalent of adual task environment, wherein participants were faced with the memory task itself aswell as trying to strategize how to overcome their forgetting after being warned about thephenomenon.

Ortega, Gómez-Ariza, Román, and Bajo (2012) suggest that dual task retrieval-practice conditions might disrupt older adults’ executive control, and hence theirretrieval-induced forgetting, more than they disrupt younger adults’. In addition, dividingattention during encoding has larger effects on memory than dividing attention duringretrieval (Anderson, Craik, & Naveh-Benjamin, 1998; Baddeley, Lewis, Eldridge, &Thomson, 1984). Thus, one might expect greater age differences in impairment forthose warned before retrieval-practice and before encoding than for those warned beforerecall. Examination of Figure 2 suggests that this is in fact the case. Also consistent withthis notion is the finding that impairment rates increased in Part 2 for all conditions; therewere differences between younger and older adults, but only in conditions in whichparticipants knew what was driving their forgetting (i.e., warning conditions). In sum,warnings served to make the task more attention-demanding, which worked against bothage groups, but more so for older than younger adults.

Experiment 2

The results of Experiment 1 suggest that raising participants’ awareness of RIF mighthave altered how participants in both age groups approached the task, thereby increasingrather than decreasing their rates of impairment. However, because participants werewarned about the memory phenomenon without being told how to address it, it remainedan open question how participants might have responded to the warning. If participantsresponded by trying to use more elaborative encoding strategies, then this could haveincreased the attentional demands and increased inhibition, thereby yielding the differ-ences that were observed in the rates of impairment across the two parts for both agegroups. Participants in both age groups reported attempting to integrate the items.However, the fact that impairment increased with awareness rather than decreasing raisesquestions about whether individuals actually integrated items, given that integrationtypically decreases RIF (Anderson & McCulloch, 1999; Goodmon & Anderson, 2011).

Experiment 2 was run in an attempt to equate participants’ encoding methods so asto allow more concrete evidence for the impact of warnings on participants’ retrieval-induced forgetting. Thus, Experiment 2 included the four conditions from Experiment 1,but incorporated instructions for participants to integrate items. Because what had been abaseline condition in Experiment 1 was now an integration-only condition, we alsoadded a baseline condition that did not receive integration instructions to allow acomparison of the two non-warned conditions’ (i.e., integration-only [no warning]condition and a no warning/no integration baseline condition) performance. Of interestwas whether impairment rates would be affected by the integration instructions and thedifferently timed warnings. The underlying assumption was that equating how partici-pants attempted to encode items and counteract RIF would provide insight on whetherparticipants have conscious control over their RIF or whether raising awarenessincreases participants’ forgetting.

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If integration instructions serve to reduce RIF, then those instructed to integrate shouldhave lower rates of impairment than those in the no warning/no integration baselinecondition. However, if raising awareness of the RIF phenomenon increases participants’forgetting, then those in the warning conditions should have higher rates of impairmentthan those in the baseline and integration-only (no warning) conditions. We opted to onlytest younger adults in Experiment 2, given concerns about disentangling the effects of ourmanipulations and age effects. We examined these issues as follows.

Method

Participants

Participants were 130 undergraduate students (18–25 years of age; M age = 19.81,SD = 1.76; M years of education = 14.49, SD = 0.92; 69% female) who were recruitedand compensated as in Experiment 1.7 Random assignment to conditions yielded 26 in thebaseline condition, 26 in the integration instructions condition, 27 in the pre-encodingwarning plus integration instructions condition, 25 in the pre-retrieval-practice warningplus integration instructions condition, and 26 in the pre-recall warning plus integrationinstructions condition. APA guidelines were again followed throughout this experiment.

Design and materials

A 2 (Part: 1, 2) × 3 (Item type: Rp+, Rp−, Nrp) × 5 (Condition: baseline, integration-only,pre-encoding, pre-retrieval-practice, pre-recall) mixed factorial design was used withrepeated measures for Part and Item type and Condition manipulated between subjects.The dependent measures in this study were the recall accuracy of all item types, with thesevalues used to calculate facilitation and impairment effects.

The word lists used in this experiment were identical to those used in Experiment 1,with the exception that no filler categories were used in Experiment 2 to ensure that allparticipants received the same categories and the experimental stimuli were properlyrandomized. The retrieval-practice paradigm stimuli were presented via Dell desktopcomputers and 20″ monitors rather than being projected on a screen at the front of theroom. The computer program, created in LiveCode (Runtime Revolution Ltd., 2010), wasdesigned to randomly select half the categories and half the items within those categories toserve as Rp+/Rp− items, while the remaining categories and items within those categoriesserved as Nrp items. Thus, each exemplar had equal probability of being Rp+, Rp−, or Nrpfor a given participant. For each exemplar, the program recorded which type of item it wasas well as the order in which items were presented, given that all phases were randomizedanew for each participant. The program also recorded participants’ retrieval-practice andrecall responses. Responses were scored as correct if the first three letters matched a targetword, given that the first three letters of all words were unique.

Another change made in the Experiment 2 materials were the distractor tasks. Ratherthan using the tasks that were used in Experiment 1, we asked participants to countbackward by threes from some three-digit number in between each phase and then torecord the final resulting number once time elapsed, as in Aslan and Bäuml (2012). A newnumber from which they were supposed to count backward appeared on their computermonitor before each phase began and participants were instructed to count backward untilthe screen instructed them to move on to the next task. The change in distractor tasksallowed us to equate how much time occurred in between each phase across all

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conditions, so that those receiving the warnings and/or integration instructions did notexperience a greater gap between phases than did those in the baseline condition. Thus thedistractor lasted for 30 s between each phase and 1 min between the two parts.

The final change made in Experiment 2 was that the warnings (and integrationinstructions) were presented visually on the computer screen rather than read to theparticipants by the experimenter. Every attempt was made to ensure that participantsunderstood both the warning and manipulation check question. Thus, we used twocategories in our warning and integration examples, which participants would not beasked to study. All other materials were identical to those used in Experiment 1.

Procedure

The procedure in Experiment 2 was identical to that of Experiment 1 with the previouslynoted exceptions (i.e., computerized program and countdown tasks in lieu of the DigitSymbol Substitution Task and Backward Digit Span task) and the addition of theintegration instructions for all conditions except the baseline. Those who received inte-gration instructions were told to try to link the exemplars to each other as well as to theircategory cues (see Appendix 2 for the integration script). The integration instructionsalways occurred at the beginning of each part and preceded the warning. Those in thewarning conditions then received the warning about RIF at the condition-specific time(i.e., either before encoding, retrieval-practice, or recall).

Results

Retrieval-practice

A 2 × 5 (Part × Condition) ANOVAwith repeated measures for Part revealed a main effectof Part due to accuracy increasing across parts (67.7% versus 78.7%, respectively) asparticipants gained familiarity with the task, F(1, 125) = 31.96, p < 0.001, η2p = 0.20 (seeTable 3). There were no differences as a function of condition, F < 1.

Facilitation effects

Facilitation effects were examined as in Experiment 1 by running a 2 × 2 × 5 (Part × Itemtype × Condition) ANOVA with repeated measures for Part and Item type (see Table 4).Participants recalled more Rp+ items (M = 72%, SE = 1.20) than Nrp items (M = 54%,

Table 3. Retrieval-Practice means for Experiment 2 as a function of condition and part.

Part 1 Part 2

Condition M (SE) M (SE)

Baseline 62.60 (4.30) 78.00 (3.40)Integration 65.10 (4.30) 77.80 (3.40)Pre-encoding warning + integration 69.00 (4.20) 82.20 (3.40)Pre-retrieval-practice warning + integration 70.30 (4.30) 76.70 (3.50)Pre-recall warning + integration 71.30 (4.30) 78.70 (3.40)

Note: Table values are mean percentages, which were calculated by taking the mean number of items recalledduring retrieval-practice and dividing it by the total possible number of words for the retrieval-practice phase(36); standard errors are presented in the parentheses.

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SE = 1.10), which yielded a main effect of Item type, F(1, 125) = 281.76, p < 0.001,η2p = 0.69. The Part × Item type interaction was not significant, F < 1. Separate analyses offacilitation effects for each part revealed significant yet similar rates of facilitation in bothPart 1 (M = 18.60, SE = 1.45), F(1, 125) = 145.50, p < 0.001, η2p = 0.54, and Part 2(M = 17.7, SE = 1.25), F(1, 125) = 174.30, p < 0.001, η2p = 0.58. Facilitation did not differacross conditions, F < 1 (see Figure 3).

Impairment effects

Impairment effects were analyzed as in Experiment 1 by running a 2 × 2 × 5 (Part × Itemtype × Condition) ANOVAwith repeated measures for Part and Item type (see Table 4). Thisanalysis yielded a main effect of Item type, given that participants recalled Rp− items(M = 43%, SE = 1.40) at a lower level than Nrp items (M = 54%, SE = 1.10),F(1, 125) = 130.85, p < 0.001, η2p = 0.51. The Part × Item type interaction was also marginally

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Figure 3. Mean facilitation effects for Part 1 and Part 2 as a function of condition in Experiment 2.

Table 4. Mean recall percentages for each item type as a function of condition and part inExperiment 2.

Part 1 Part 2

Condition Rp+ Rp− Nrp Rp+ Rp− Nrp

Baseline 64 (4) 39 (4) 49 (3) 76 (3) 48 (4) 59 (3)Integration 64 (4) 38 (4) 46 (3) 75 (3) 50 (4) 63 (3)Pre-encoding warning 70 (4) 43 (4) 52 (3) 79 (3) 46 (4) 63 (3)Pre-retrieval-practice warning 69 (4) 36 (4) 44 (3) 79 (3) 46 (4) 58 (3)Pre-recall warning 70 (4) 41 (4) 53 (3) 78 (3) 44 (4) 56 (3)Overall 67 (2) 39 (2) 49 (1) 77 (1) 47 (2) 60 (1)

Note: Table values are mean recall and standard errors (in parentheses) associated with each item type, separatedby condition and part; Item types are abbreviated as follows: Rp+ = strengthened items; Rp− = non-strengtheneditems; Nrp = unpracticed items; Baseline condition = participants in the control condition who were not exposedto any experimental manipulation; Integration = participants who did not receive a warning, but were told to tryto integrate items; Pre-encoding warning = participants warned before they began the Part 1 and Part 2 encodingphases who were also told to try to integrate items; Pre-retrieval-practice warning = participants warned beforethe retrieval-practice phase in each part who were also instructed to try to integrate items; Pre-recall warn-ing = participants warned before the recall phase in each part who were told to try to integrate items.

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significant, reflecting the tendency for impairment to increase across parts (Part 1: M = 9.5,SE = 1.45 and Part 2:M = 12.7, SE = 1.40), F(1, 125) = 2.86, p = 0.09, η2p = 0.02. While thisinteraction did not reach significance, main effects of Item type (i.e., impairment effects) werepresent in Part 1: F(1, 125) = 43.39, p < 0.001, η2p = 0.26, and Part 2: F(1, 125) = 97.09,p < 0.001, η2p = 0.44, when each part was analyzed separately. However, there were nodifferences in impairment as a function of condition in the analyses, F < 1 (see Figure 4).

Post-task questionnaire responses

As in Experiment 1, we ran Chi-square analyses to examine whether there were differ-ences across conditions in participants’ responses. Most participants (98%) reported tryingto integrate items. This did not differ across conditions, despite those in the no warning/nointegration baseline condition being the only group to not receive integration instructions.Most participants (80%) reported believing they had higher recall for some item typesthan others. Rp+ items were again ranked as having the highest recall. However, Nrpitems were ranked as having the lowest recall, with Rp− items falling in the middle. Thebulk of participants (81%) reported studying more words than they were able to recall, but88% said they found it easier to recall the Rp+ items, and 31% said recalling the Rp+items interfered with their ability to recall both Rp− and Nrp items. Most participants(48%) claimed they became aware of their inability to recall certain words during the Part1 recall test. Nonetheless, most reported that they did not change the way they approachedPart 2 encoding (57%), retrieval-practice (85%), or recall (83%).

Discussion

Prior research suggests that integrating items can reduce RIF (Anderson & McCulloch,1999; Goodmon & Anderson, 2011). Of interest was how integration instructions wouldinteract with the differently timed warnings to affect participants’ rates of impairment. Theresults indicated that while integration instructions might have helped maintain slightlylower rates of impairment in Part 1 than in Part 2, participants in all conditions experi-enced forgetting. Moreover, the rates of impairment increased in all conditions as parti-cipants gained greater experience and awareness within the retrieval-practice paradigm.The fact that the no warning/no integration baseline condition obtained similar rates of

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impairment as those in the integration-only baseline and warning conditions may be dueto all groups utilizing integration to a similar extent, as assessed by participants’ post-taskquestionnaire responses. It is unclear, however, why impairment rates were not reduced ifparticipants did, in fact, integrate items. It remains possible that despite explicit instruc-tions regarding how to integrate items, participants did not fully integrate items (e.g., onlylinked the exemplars to their category cues, but not to one another). Another possibility isthat our integration instructions increased cognitive load, given that they were moredetailed than the integration instructions given by Anderson and McCulloch (1999).They found the highest rates of integration, and lowest impairment, when individualswere exposed to the encoding phase twice. It remains possible that had we allowed ourparticipants a second opportunity to integrate the items within each part that we wouldalso have found more integration and less impairment. Unfortunately, our method and thedata do not allow examination of this possibility. Nonetheless, Experiment 2 providesadditional evidence that warnings do not reduce RIF.

Comparing Experiment 1 and Experiment 2

Although we included the differently timed warnings in both experiments, the warn-ings in Experiment 2 followed the instructions to integrate items. Thus, it remainedpossible that warnings, when combined with integration instructions, created too muchcognitive load, thereby reducing the effectiveness of either the integration instructionsor warnings. Although we did not include any warning conditions in Experiment 2that did not also contain integration instructions, none of the conditions in Experiment1 were instructed to integrate. Thus, we examined the possibility of the combined(i.e., integration plus warning) instructions creating too much cognitive load bycomparing the rates of facilitation and impairment across the two experiments. Weexcluded older adults in Experiment 1 and those in the integration-only condition inExperiment 2 from our analyses, so that only the younger adults in the no warning/nointegration baseline and warning conditions from each experiment were compared inour analyses.

Retrieval-practice

We first examined whether retrieval-practice performance differed across experiments byrunning a 2 × 2 × 4 (Experiment × Part × Condition) ANOVAwith repeated measures on Part.This analysis yielded a main effect of Part, F(1, 203) = 87.04, p < 0.001, η2p = 0.30, reflectingthe previously noted tendency for performance to increase from Part 1 (M = 67.9%,SE = 1.40) to Part 2 (M = 80.6%, SE = 1.20), once participants gained familiarity with theretrieval-practice paradigm. No other effects or interactions were significant.

Facilitation effects

To compare facilitation rates across experiments, we ran a 2 × 2 × 2 × 4(Experiment × Part × Item type × Condition) ANOVA with repeated measures on Partand Item type. This analysis yielded a main effect of Item Type, F(1, 203) = 629.20,p < 0.001, η2p = 0.76, as well as an Experiment × Item type × Condition interaction,F(3, 203) = 3.00, p < 0.05, η2p = 0.04. The main effect of Item type reflects the tendencyfor Rp+ items to be recalled at a higher rate (M = 72%, SE = 1.00) than Nrp items(M = 51%, SE = 0.90) across both experiments. The three-way interaction is driven by the

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fact that the difference in Rp+ and Nrp items differed across experiments for the fourconditions, such that facilitation rates were higher in Experiment 1 for those in thebaseline (24%) and pre-encoding (25%) conditions than for those who received thewarning before retrieval-practice (21%) or before recall (18%). In contrast, when integra-tion instructions were included with the warnings in Experiment 2, facilitation rates wereactually lower in the baseline (16%) and pre-encoding (17%) conditions and higher forthose who received the warning before retrieval-practice (23%) and before recall (20%).This suggests that receiving integration instructions and the warning right before the studyphase may have yielded cognitive load for those in the pre-encoding condition, therebyreducing facilitation effects in this condition in Experiment 2.

Impairment effects

We compared rates of impairment across experiments by running a 2 × 2 × 2 × 4(Experiment × Part × Item type × Condition) ANOVA with repeated measures on Partand Item type. The analyses yielded a main effect of Item Type, F(1, 203) = 171.91,p < 0.001, η2p = 0.46, as well as interactions of Part × Item type, F(1, 203) = 5.79,p < 0.05, η2p = 0.03, and Experiment × Item type, F(1, 203) = 4.56, p < 0.05, η2p = 0.03.The main effect of Item type was driven by the tendency of participants in both experi-ments to recall Rp− items (M = 42%, SE = 1.00) at a lower rate than Nrp items (M = 51%,SE = 0.90). The interactions of Part × Item type and Experiment × Item type reflected thefact that rates of impairment were lower in Part 1 (8%) than in Part 2 (11%), collapsingacross experiments, but higher rates of impairment were observed in Experiment 2 (11%)than in Experiment 1 (8%). The Experiment × Item type × Condition interaction was notsignificant, F < 1, suggesting that rates of impairment did not differ across the twoexperiments for the baseline and warning conditions, despite the warnings being com-bined with integration instructions in Experiment 2.

General discussion

These experiments investigated whether explicit warnings would alleviate RIF, and inparticular, whether altering the timing of the warning would provide insight as to whenthe warning should be given to reduce younger and older adults’ RIF. In both experiments,we found that warnings served to increase rather than decrease impairment for both olderand younger adults. Including integration instructions in Experiment 2 also did not serve toreduce participants’ forgetting.

The two dominant accounts suggest that the inhibitory or noninhibitory mechanismsunderlying RIF occur without intention (e.g., Anderson, 2003, 2005; Veling & vanKnippenberg, 2004). However, Carroll et al. (2007) suggest that participants may becomeaware of their forgetting. Thus, we hypothesized that even if unintentional inhibitory ornoninhibitory mechanisms were initially responsible for participants’ forgetting, partici-pants might still be capable of addressing their forgetting (e.g., via intentional encoding orretrieval strategies) once they became aware of the phenomenon. Given findings in themetacognitive literature (Carroll et al., 2007; Hertzog et al., 2008, 2009; Price et al.,2008), it seemed reasonable that individuals might be able to spontaneously recognizetheir forgetting after experiencing the Part 1 recall test (Hertzog et al., 2008). However, wealso reasoned that an explicit warning might be necessary to make participants aware oftheir forgetting.

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Warnings have an extensive history of alleviating encoding and retrieval issues(Chambers & Zaragoza, 2001; Echterhoff et al., 2005; Gallo et al., 1997; McDermott &Roediger, 1998; Pelegrina et al., 2000). However, the results obtained in the presentstudies support the notion that warning participants about the RIF phenomenon increasesrather than decreases rates of impairment in the retrieval-practice paradigm. In fact, thepositive relationship between awareness and impairment rates can be seen in bothexperiments and seems to pinpoint when participants were warned or gained familiaritywith the paradigm in each experiment. First, in both experiments, as participants inbaseline conditions gained awareness of the paradigm, we observed an increase ratherthan a decrease in impairment effects across parts. Second, in Experiment 1, we observedhigher rates of forgetting in Part 1 for warned participants than baseline participants(collapsing across age groups), again suggesting that awareness increased rather thandecreased forgetting.

A comparison of the two experiments revealed that retrieval-practice performance wassimilar in both experiments. Facilitation effects were also similar, collapsing acrossconditions, but the rates of facilitation differed slightly for the various conditions as afunction of experiment, which yielded the interaction noted in the cross-experimentcomparison. In contrast, impairment effects were larger in Experiment 2 than inExperiment 1, in particular in Part 1. However, in both experiments, by Part 2, participantsin all conditions experienced similar rates of impairment, which again raises questionsabout the role of awareness in RIF. At issue are why awareness would increase rather thandecrease forgetting in both experiments and why the rates of RIF are greater in older thanyounger adults.

While our experiments were not designed to address whether the mechanism drivingparticipants’ forgetting is inhibitory or noninhibitory, our results suggest that the under-lying mechanism is more active once participants gain awareness of the retrieval-practiceparadigm. As described by Anderson (2005), this could occur as a result of the nature ofour cued-recall test. That is, because we used the original category cues rather thanindependent cues (e.g., Anderson & Spellman, 1995) and did not use exemplar stems tocontrol for output order, our results likely reflect a combination of both inhibition andinterference. Although our warning likely increased the attentional demands of the task,Anderson (2005) notes that inhibition and interference are typically differentially affectedby attentional deficits or tasks that require dividing attention (e.g., dual task conditions).He suggests that impairment effects should be reduced when individuals have deficientattentional inhibition, since they will be less able to inhibit Rp− items. However, he arguesthat the same deficiency should increase how much interference individuals experiencefrom the Rp+ items, which will increase participants’ RIF. Anderson further suggests thatthe more difficulty individuals have combating interference on the recall test, the largerthe forgetting effects will be.

When our results are interpreted in light of Anderson’s (2005) claims, it seems likelythat raising participants’ awareness of the RIF phenomenon yielded more interferenceand, in turn, higher rates of impairment for our participants. If, as Anderson suggests, ourwarnings yielded a more attention-demanding task, then this would both decrease theamount of inhibition participants experienced during retrieval-practice and increase theamount of interference participants experienced during the recall test, which would yieldthe higher impairment effects that we observed in both experiments. This held for bothage groups, but more so for older adults than younger adults. Thus, while our warning andintegration instructions were designed to raise participants’ awareness of the phenomenonand a way to address it, both would have required quite a bit of cognitive effort to address.

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Anderson’s proposal can explain why combining integration instructions with the warningin Experiment 2 yielded higher rather than lower rates of impairment, given that this isexactly what would be predicted if participants experienced greater cognitive load or theequivalent of dual task conditions when trying to integrate and find a way to address thewarning.

Although the observed age differences might be expected, given age-related declinesin executive (Salthouse & Babcock, 1991) and inhibitory control (Hasher & Zacks, 1988),our data do not allow us to state whether the observed increases in retrieval-inducedforgetting reflect inhibitory or noninhibitory mechanisms. We are also unable to draw anyconclusions about age-related inhibitory deficits and what role they may have played inour results (Anderson, 2005).

Experiment 1 raised questions about how the warnings might have altered partici-pants’ encoding and retrieval strategies. Although participants in the first experimentreported integrating items, the rates of forgetting were inconsistent with their reports.This raised concerns about the validity of their retrospective reports. This was the basis forincluding integration instructions in Experiment 2. However, it seems unlikely that ourwarning and integration instructions inspired participants to engage in enhanced encodingor retrieval processes, given that the Part 1 means in both experiments are similar to thoseobtained in prior experiments (e.g., Anderson et al., 1994). Yet, our data do show anincrease in recall across parts for all three item types and retrieval-practice in bothexperiments. If awareness of the paradigm altered participants’ rehearsal strategies duringthe encoding phase or inspired them to engage in covert retrieval-practice, then this couldhave contributed to the magnitude of the impairment effects observed in Part 2 across thetwo experiments. Alternatively, participants’ recall performance may have changed acrossparts simply because they had gained exposure to the task and the nature of the stimuli.Our data do not allow us to disentangle these two options.

Together, the results of both experiments suggest that awareness of the paradigm,whether gleaned through experience or an explicit warning, serves to increase rather thandecrease RIF. The strength of the RIF phenomenon is observed both in the fact thatexplicitly warned participants could not overcome their forgetting and in the consistencyof the recall means for each item type across the two experiments. Tables 2 and 4 revealsimilar means for both experiments, collapsing across the conditions (and age groups inExperiment 1). This is interesting, given the methodological changes made across experi-ments (i.e., the addition of integration instructions and the move from a single presenta-tion order in Experiment 1 to completely random presentation orders in Experiment 2).These changes and the fact that we did not control for recall output order are limitations ofthis work.

Researchers should continue investigating RIF in an attempt to reduce, if not altogethereliminate it because of the important implications for education and eyewitness memory.For example, a large body of research suggests that testing oneself on material is morebeneficial than studying the material longer (e.g., Roediger & Karpicke, 2006). However,the RIF literature runs counter to predictions of the testing effects literature and suggests thattesting oneself might enhance recall of practiced items but impair recall of other related, butunpracticed (i.e., Rp−), items (Macrae & MacLeod, 1999). Moreover, work by Carroll et al.(2007) suggests that novice students may be more prone to RIF than experts in a domain,who might be more inclined to integrate items, thereby reducing the amount of forgettingthey experience.

Impairment effects may also have real-world implications for eyewitness memory.Several studies have now shown that RIF can occur in eyewitness memory (MacLeod &

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Saunders, 2008; Saunders & MacLeod, 2002; Shaw, Bjork, & Handal, 1995). Thissuggests that if eyewitnesses are asked to describe some, but not all, of what theywitnessed, the related information may be forgotten or misremembered.

Thus, future research should examine whether warnings are influencing inhibitory ornoninhibitory mechanisms by controlling for output order and using independent probemethods (Anderson, 2005). This might clarify why warnings are beneficial in addressingeyewitness memory errors, but increase forgetting in the retrieval-practice paradigm, atleast as implemented in our studies. If future research supports our finding that raisingawareness increases rather than decreases RIF, then it will be important to identify otherways to address participants’ forgetting.

AcknowledgmentWe would like to acknowledge the assistance of Nicholas J. Martin, Barbara J. Wright, MelissaCavins, Meredith Knight, Joshlyn Shareck, Alan Harrison, Jessica Floyd, Brittany Sentell, JessicaHays, and Kenneth Hammett in data collection and preparation.

FundingThis research was supported by a Junior Faculty Distinguished Research grant awarded to Jodi Pricefrom The University of Alabama in Huntsville.

Notes1. We examined whether there were differences in education levels across the two age groups or

conditions in Experiment 1 that could yield differences in performance. The older adults hadachieved significantly more education than younger adults, F(1, 205) = 68.05, p < 0.001,η2p = 0.25. However, no differences in education were found across or within conditions foreither age group, p > 0.05.

2. Approximately 85% of our older adult participants were recruited from the chapter of the OsherLifelong Learning Institute (OLLI) on the University of Alabama in Huntsville campus. OLLImembers tend to be slightly more cognitively and physically active than the general populationof older adults, given that they are well enough to drive to and attend weekly OLLI meetingsand continuing education classes.

3. We analyzed the number of times participants within each age group and condition heard thewarning before answering the manipulation check question correctly. The number of times itwas necessary to present the warning decreased across parts, but did not differ as a function ofcondition or age group, and there was no difference in either part in impairment effects as afunction of the number of times participants heard the warning.

4. For completeness, we assessed whether there were age differences in performance on thedistractor tasks in Experiment 1. On both the Digit Symbol Substitution Task (maximumscore 35; Jackson, 1984) and the Digit Span Task (maximum score 158; Wechsler, 1997),younger adults scored significantly higher than older adults (Younger: M = 30.50, SE = 0.42and M = 109.14, SE = 2.26; Older: M = 22.08, SE = 0.52 and M = 79.13, SE = 3.33), p < 0.05.

5. Using category cues (e.g., FRUIT) rather than category cues with exemplar stems (e.g., FRUIT –O____) during the recall phases removed our ability to investigate whether the underlyingmechanism is inhibitory or noninhibitory, but ensured we would obtain impairment effects inour baseline condition (see Anderson et al., 1994, for this argument), which was critical for askingwhether warnings would counteract these effects.

6. When calculating impairment effects, the results are often negative numbers, reflecting lowerrecall of Rp− items than Nrp items. Throughout the manuscript, we have focused on theabsolute value, removing the minus signs, to enhance clarity.

7. As in Experiment 1, no differences in education were found across conditions, p > 0.05.

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ReferencesAnderson, M. C. (2003). Rethinking interference theory: Executive control and the mechanisms of

forgetting. Journal of Memory and Language, 49, 415–445. doi:10.1016/j.jml.2003.08.006Anderson, M. C. (2005). The role of inhibitory control in forgetting unwanted memories: A

consideration of three methods. In N. Ohta, C. M. MacLeod, & B. Uttl (Eds.), Dynamiccognitive processes (pp. 159–189). Tokyo: Springer-Verlag.

Anderson, M. C., & Bjork, R. A. (1994). Mechanisms of inhibition in long-term memory: A newtaxonomy. In D. Dagenbach & T. Carr (Eds.), Inhibitory processes in attention, memory andlanguage (pp. 265–326). San Diego, CA: Academic Press.

Anderson, M. C., Bjork, R. A., & Bjork, E. L. (1994). Remembering can cause forgetting: Retrievaldynamics in long-term memory. Journal of Experimental Psychology: Learning, Memory, andCognition, 20, 1063–1087. doi:10.1037/0278-7393.20.5.1063

Anderson, M. C., & McCulloch, K. C. (1999). Integration as a general boundary condition onretrieval-induced forgetting. Journal of Experimental Psychology: Learning, Memory, andCognition, 25, 608–629. doi:10.1037/0278-7393.25.3.608

Anderson, M. C., & Spellman, B. A. (1995). On the status of inhibitory mechanisms in cognition:Memory retrieval as a model case. Psychological Review, 102, 68–100. doi:10.1037/0033-295X.102.1.68

Anderson, N. D., Craik, F. I., & Naveh-Benjamin, M. (1998). The attentional demands of encodingand retrieval in younger and older adults: I. Evidence from divided attention costs. Psychologyand Aging, 13, 405–423. doi:10.1037/0882-7974.13.3.405

Andrés, P., Guerrini, C., Phillips, L., & Perfect, T. (2008). Differential effects of aging on executiveand automatic inhibition. Developmental Neuropsychology, 33, 101–123. doi:10.1080/87565640701884212

Aslan, A., Bauml, K., & Pastotter, B. (2007). No inhibitory deficit in older adults’ episodic memory.Psychological Science, 18, 72–78. doi:10.1111/j.1467-9280.2007.01851.x

Aslan, A., & Bäuml, K.-H. T. (2012). Retrieval-induced forgetting in old and very old age.Psychology and Aging, 27, 1027–1032. doi:10.1037/a0028379

Baddeley, A. D., Lewis, V., Eldridge, M., & Thomson, N. (1984). Attention and retrieval from longterm memory. Journal of Experimental Psychology: General, 113, 518–540. doi:10.1037/0096-3445.113.4.518

Battig, W. F., & Montague, W. E. (1969). Category norms of verbal items in 56 categories – Areplication and extension of Connecticut category norms. Journal of Experimental PsychologyMonograph, 80, 1–46. doi:10.1037/h0027577

Carroll, M., Campbell-Ratcliffe, J., Murnane, H., & Perfect, T. (2007). Retrieval-induced forgettingin educational contexts: Monitoring, expertise, text integration, and test format. EuropeanJournal of Cognitive Psychology, 19, 580–606. doi:10.1080/09541440701326071

Chambers, K. L., & Zaragoza, M. S. (2001). Intended and unintended effects of explicit warningson eyewitness suggestibility: Evidence from source identification tests. Memory & Cognition,29, 1120–1129. doi:10.3758/BF03206381. Retrieved from http://mc.psychonomic-journals.org/content/29/8/1120.full.pdf

Conway, M. A., & Fthenaki, A. (2003). Disruption of inhibitory control of memory following lesionsto the frontal and temporal lobes. Cortex, 39, 667–686. doi:10.1016/S0010-9452(08)70859-1

Deese, J. (1959 ). On the prediction of occurrence of particular verbal intrusions in immediate recall.Journal of Experimental Psychology, 58, 17–22. doi:10.1037/h0046671

Dunlosky, J., & Hertzog, C. (2000). Updating knowledge about encoding strategies: A componentialanalysis of learning about strategy effectiveness from task experience. Psychology and Aging,15, 462–474. doi:10.1037/0882-7974.15.3.462

Dunlosky, J., Hertzog, C., & Powell-Moman, A. (2005). The contribution of mediator-baseddeficiencies to age differences in associative learning. Developmental Psychology, 41,389–400. doi:10.1037/0012-1649.41.2.389

Echterhoff, G., Hirst, W., & Hussy, W. (2005). How eyewitnesses resist misinformation: Socialpostwarnings and the monitoring of memory characteristics. Memory & Cognition, 33,770–782. doi:10.3758/BF03193073

Gallo, D. A., Roberts, M. J., & Seamon, J. G. (1997). Remembering words not presentedin lists: Can we avoid creating false memories? Psychonomic Bulletin & Review, 4, 271–276. doi:10.3758/BF03209405. Retrieved from http://www.wjh.harvard.edu/~dgallo/Galloetal97.pdf

Aging, Neuropsychology, and Cognition 21

Dow

nloa

ded

by [L

aure

n Jo

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at 0

9:37

23

Oct

ober

201

4

Gómez-Ariza, C. J., Pelegrina, S., Lechuga, M. T., Suárez, A., & Bajo M. T. (2009). Inhibition andretrieval of facts in young and older adults. Experimental Aging Research, 35, 83–97.doi:10.1080/03610730802545234

Goodmon, L. B., & Anderson, M. C. (2011). Semantic integration as a boundary condition oninhibitory processes in episodic retrieval. Journal of Experimental Psychology: Learning,Memory, and Cognition, 37, 416–436. doi:10.1037/a0021963

Hartman, M., & Hasher, L. (1991). Aging and suppression: Memory for previously relevantinformation. Psychology and Aging, 6, 587–594. doi:10.1037/0882-7974.6.4.587

Hasher, L., & Zacks, R. T. (1988). Working memory, comprehension, and aging: A review and anew view. In G. H. Bower & G. H. Bower (Eds.), The psychology of learning and motivation:Advances in research and theory (Vol. 22, pp. 193–225). San Diego, CA: Academic Press.doi:10.1016/S0079-7421(08)60041–9

Hertzog, C., Price, J., Burpee, A., Frentzel, W. J., Feldstein, S., & Dunlosky, J. (2009). Why dopeople show minimal knowledge updating with task experience: Inferential deficit or experi-mental artifact? The Quarterly Journal of Experimental Psychology, 62, 155–173. doi:10.1080/17470210701855520. Retrieved from http://dept.kent.edu/psychology/MClab/files/pubbies/HZog%20Updating%20QJEP.pdf

Hertzog, C., Price, J., & Dunlosky, J. (2008). How is knowledge generated about memory encodingstrategy effectiveness? Learning and Individual Differences, 18, 430–445. doi:10.1016/j.lindif.2007.12.002

Hogge, M., Adam, S., & Collette, F. (2008). Retrieval-induced forgetting in normal ageing. Journalof Neuropsychology, 2, 463–476. doi:10.1348/174866407X268533

Jackson, D. N. (1984). Multidimensional aptitude battery manual. Port Huron, MI: ResearchPsychologist Press.

LiveCode. (2010). LiveCode (Version 4.5.1) [Computer software]. Edinburgh: Runtime RevolutionLtd.

MacLeod, M. D., & Saunders, J. (2008). Retrieval inhibition and memory distortion: Negativeconsequences of an adaptive process. Current Directions in Psychological Science, 17, 26–30.doi:10.1111/j.1467-8721.2008.00542.x

Macrae, C. N., & MacLeod, M. D. (1999). On recollections lost: When practice makes imperfect.Journal of Personality and Social Psychology, 77, 463–473. doi:10.1037/0022-3514.77.3.463

McDermott, K. B., & Roediger, H. L. (1998). Attempting to avoid illusory memories: Robust falserecognition of associates persists under conditions of explicit warnings and immediate testing.Journal of Memory and Language, 39, 508–520. doi:10.1006/jmla.1998.2582

Neuschatz, J. S., Benoit, G. E., & Payne, D. G. (2003). Effective warnings in the Deese-Roediger-McDermott false-memory paradigm: The role of identifiability. Journal ofExperimental Psychology: Learning, Memory, and Cognition, 29, 35–41. doi:10.1037/0278-7393.29.1.35

Ortega, A., Gómez-Ariza, C. J., Román, P., & Bajo, M. T. (2012). Memory inhibition, aging, and theexecutive deficit hypothesis. Journal of Experimental Psychology: Learning, Memory, andCognition, 38, 178–186. doi:10.1037/a0024510

Pelegrina, S., Bajo, M. T., & Justicia, F. (2000). Differential allocation of study time: Incompletecompensation for the difficulty of the materials. Memory, 8, 377–392. doi:10.1080/09658210050156831

Price, J., Hertzog, C., & Dunlosky, J. (2008). Age-related differences in strategy knowledgeupdating: Blocked testing produces greater improvements in metacognitive accuracy foryounger than older adults. Aging, Neuropsychology, and Cognition, 15, 601–626.doi:10.1080/13825580801956225

Roediger, H. L., & Karpicke, J. D. (2006). Test-enhanced learning: Taking memory tests improveslong-term retention. Psychological Science, 17, 249–255. doi:10.1111/j.1467-9280.2006.01693.x

Roediger, H. L., & McDermott, K. (1995). Creating false memories: Remembering words notpresented in lists. Journal of Experimental Psychology: Learning, Memory, & Cognition, 21,803–814. doi:10.1037/0278-7393.21.4.803

Salthouse, T. A. (1996). The processing-speed theory of adult age differences in cognition.Psychological Review, 103(3), 403–428. doi:10.1037/0033-295X.103.3.403

Salthouse, T. A., & Babcock, R. L. (1991). Decomposing adult age differences in working memory.Developmental Psychology, 27, 763–776. doi:10.1037/0012-1649.27.5.763

22 J. Price et al.

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ded

by [L

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n Jo

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at 0

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23

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201

4

Saunders, J., & MacLeod, M. D. (2002). New evidence on the suggestibility of memory: The role ofretrieval-induced forgetting in misinformation effects. Journal of Experimental Psychology:Applied, 8, 127–142. doi:10.1037/1076-898X.8.2.127

Shaw, J. S. I., Bjork, R. A., & Handal, A. (1995). Retrieval-induced forgetting in an eye-witness memory paradigm. Psychonomic Bulletin & Review, 2, 249–253. doi:10.3758/BF03210965

Spieler, D. H., Balota, D. A., & Faust, M. E. (1996). Stroop performance in healthy younger andolder adults and in individuals with dementia of the Alzheimer’s type. Journal of ExperimentalPsychology: Human Perception and Performance, 22, 461–479. doi:10.1037/0096-1523.22.2.461

Storm, B. C., & Levy, B. J. (2012). A progress report on the inhibitory account of retrieval-inducedforgetting. Memory and Cognition, 40, 827–843. doi:10.3758/s13421-012-0211-7

Titz, C., & Verhaeghen, P. (2010). Aging and directed forgetting in episodic memory: A meta-analysis. Psychology and Aging, 25, 405–411. doi:10.1037/a0017225

Veling, H., & van Knippenberg, A. (2004). Remembering can cause inhibition: Retrieval-inducedinhibition as cue independent process. Journal of Experimental Psychology: Learning, Memory,and Cognition, 30, 315–318. doi:10.1037/0278-7393.30.2.315

Wechsler, D. (1997). WAIS-III administration and scoring manual. San Antonio, TX: ThePsychological Corporation.

Westerberg, C. E., & Marsolek, C. J. (2006). Do instructional warnings reduce false recognition?Applied Cognitive Psychology, 20, 97–114. doi:10.1002/acp.1170

Williams, C. C., & Zacks, R. T. (2001). Is retrieval-induced forgetting an inhibitory process? TheAmerican Journal of Psychology, 114, 329–354. doi:10.2307/1423685

Zacks, R. T., Radvansky, G., & Hasher, L. (1996). Studies of directed forgetting in older adults.Journal of Experimental Psychology: Learning, Memory, and Cognition, 22, 143–156.doi:10.1037/0278-7393.22.1.143

Appendix 1. Warning scriptThere is a common memory phenomenon known as retrieval-induced forgetting, or RIF, whereinpracticing certain items influences one’s ability to remember other items from the same category. Forexample, if you are asked to study items like STEEL and IRON from the category ofMETALS, and thenyou were asked to practice retrieving the word STEEL but not the word IRON, during a memory test,you would be more likely to remember the word STEEL and less likely to remember the word IRON.

Next screenNow that you have a little information regarding what RIF is, please read and respond to the

question below by typing in the number corresponding to the correct answer:What type of RIF item is most likely to be forgotten?

(1) STEEL – The word from the category METALS that you practiced remembering(2) IRON – The word from the category METALS that you did not practice

remembering(3) TRUCK – A word from the category VEHICLES for which no items were

practiced.

Note: The warning instructions changed slightly from Experiment 1 to Experiment, 2 such that inExperiment 1, participants were read the warning about retrieval-induced forgetting and were thenasked to indicate the three item types that they were most likely to forget. Given the change to acomputerized format in Experiment 2, we used the text above and dropped option 3 (i.e., the ‘truck’option representing Nrp items) from our manipulation check question in Experiment 2.

Appendix 2. Integration scriptThere is a strategy that you can use to better remember the items you will be shown. This strategy iscalled integration. Integration is simply linking the word to the category name it is presented withand to other words within the same category. For example, if you saw the word pair VEHICLE –

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AIRPLANE, you should try to form a mental link between the words VEHICLE and AIRPLANE.In this case, AIRPLANE is a type of VEHICLE. You should also try to link all of the other words inthe category as you see them. For example, you may also see VEHICLE – BOAT, VEHICLE –TRUCK, and VEHICLE – VAN. You should try to form a link among all four words: AIRPLANE,BOAT, TRUCK, and VAN. You could do this by mentally telling yourself that AIRPLANE, BOAT,TRUCK, and VAN are all types of VEHICLES.

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