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Clues to insight during incubation

Kevin S. Smith

Eastern Kentucky University

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Abstract

The present study looked at the OA theory of incubation which

states that incubation is a result of an individual’s chance

encounter with relevant information from the environment (Seifert

et al. 1994). Participants completed an initial task with

difficult riddles, and then took a break during which they were

either randomly exposed to an alternative task with clues related

to the riddles, a task without clues, or continuous work without

a break. Those whom completed the clues or no clues task was then

reintroduced to the riddles from the beginning of the study for

one final attempt. A One-Way ANOVA found a significant effect

among conditions. Directions for future research are discussed.

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Clues to insight during incubation

Wallas (1926) described that the creativity of thought

required four elements: 1) preparation, 2) incubation, 3)

illumination, and 4) verification. Applying this creative process

to problem solving, preparation would mark the time of first

introduction between thought and a problem-solving task. Then,

either illumination and verification, or an impasse (no solution)

is concluded. If no solution can be verified, then incubation is

needed. Incubation is often necessary to help an individual

achieve insight into a problem-solving task.

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Wallas (1926) beleived the occurrence of sudden insight was

spontanous and it could be achieved either while performing an

unrelated task, or while the problem solver did nothing at all

except take a break from the problem solving task. These two

types of incubation periods have since been termed autonomous and

interactive incubation (Christensen & Schunn, 2005). Autonomous

incubation refers to the occurance of sudden insight after only

the passage of time whereas interactive incubation referes to the

occurance of sudden insight being the result of an external

enviornmental cue.

Seifert Meyer, Davidson, Patalano, and Yaniv (1994) uses the

Oppourtunistic Assimilation theory to explain and test for

incubation effects. The OA theory of incubation is interactive

and suggests that the reason for some cases of sudden insight is

due to an individual encountering relevant information from the

enviornment pertaining to an unsolved problem. They explained

that once a person encounters a problem in which they cannot

solve, “faliure indices” pertaining to the problem are encoded to

long term memory. These faliure indices refered to elements of

the unsolved problem.

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Interestingly, early studies dealing with problem solving

discovered that individuals seem to have better memories for

unsolved problems than for problems they were intially able to

solve (Zeigarnik, 1938). One other explination for this effect

has been termed predictive encoding (Patalano, Seifert, &

Hammond, 1993) and may be related to failure indices. The process

of predictive encoding suggests that unmet goals are stored in

memory in a way that these unmet goals will be spontanously

recalled during encounters with relevant information from the

enviornment, favoring goal attainment. These terms may be best

understood by the following, real-life example of OA’s account of

sudden insight:

After figuring out that the copying machine at work was

nonoperational due to it being unplugged, Jim worked to

correct the problem. In fulfilling this goal Jim suddenly

recognized a possible solution to a pending goal that was

encoded the day before with an impasse when trying to start

his car to come to work (predictive encoding). He was now

able to reason (due to a chance encounter with environmental

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clues) that maybe the car was unresponsive because it had no

source of power, like the copying machine (assimilation).

This sudden insight into a possible solution as to why Jim’s

car was unresponsive could have been attributed to his encounter

with an unresponsive copying machine. Therefore, information

about a suspended goal (or tasks) may be pending within memory

for a later opportunity involving a possible resolution (see

Patalano, Seifert, & Hammond, 1993).

The presence of unmet goals and predictive encoding in LTM may

not be the only factors that affect receptivity to problem-relevant

cues during incubation. Another factor may be the type of task one

is engaged in during the incubation period. Segal (2004) argued

that a demanding task during incubation promotes insight because it

may help break a participants’ focus upon a false assumption

developed while first attempting to solve a problem. These false

assumptions are what is believed to cause an individual to

experience difficulty in solving some problems. However, other

research has found that incubation effects are more likely to occur

when tasks are cognitively undemanding (Sio & Ormerod, 2009)

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because a process of spreading activation, the generation of new

ides relevant to the target task, may be accessed within an

associative network (Yaniv & Meyer, 1987). It may not be the

characteristics of the task’s difficulty but instead be a result of

the tasks content that triggers sudden insight and makes the tasks’

difficulty seem relevant.

The current study proposes that sudden insight will be the

result of encountering problem relevant clues from an alternative

task given during the incubation phase of problem solving. Subjects

will first be asked to solve riddles, many of which should lead to

an impasse (Bowden, 1985). Secondly, subjects within the treatment

groups will engage in an alternative task during incubation in

which they will either encounter clues or no clues relevant to the

initial riddle task. Finally, subjects will be given a second

chance to solve the riddles. The specific design of the experiment

includes three groups: 1) clues group, 2) no-clues group, and 3)

no-break group. The no-break group will work on the riddles

continuously without any breaks. Through encountering relevant

information with an unsolved problem during a break, and assuming

predictive encoding has taken place, participants should show the

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most improvement with problem solving, in the clues group, because

it should trigger sudden insight and help an individual think about

the problem from a different perspective than the initial one. This

should also help them break any false assumption they might have

initially developed during the preparatory phase.

Method

Participants

Students from Eastern Kentucky University (EKU) were

recruited for this study (N = 78). Participants were randomly

assigned to one of three conditions: 1) clues-group (n = 26), 2)

no clues-group (n = 22), or 3) no break-group (n = 30).

Materials

Riddles. Upon consent (Appendix A), a riddle booklet

containing three riddles were presented to subjects (Appendix B).

One problem in particular was taken from Gibson, Dhuse,

Hrachovec, and Grimm (2011) and has been shown to be extremely

difficult, in that no single participant was able to solve it; it

reads:

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Try and explain the following: A man walks in a room and finds another man

lying on the floor shot and on the ground are 53 bicycles. What could be a

possible reason for the man being shot and 53 bicycles being on the floor?

This difficult riddle should ensure that at least one impasse is

reached by a majority of the participants. The other riddles were

chosen from a pool of riddles as described in the procedure

section below. Each riddle was listed on a single page of a

booklet. Subjects had a separate answer sheet for writing their

solutions (Appendix C).

Sentence Judgement Task (SJT). This task was a Power Point

slide show in which each slide contained a statement or a number.

Most of the statements were non-targets, but occasionally a

target statement was presented after a numbered slide that either

contained a clue or no clue statement relevant to one of the

riddles (see Appendix D). The numbered slides corresponding with

the target slides also corresponded with the appropriate number

on the SJT answer sheet (Appendix E). That means if a target

statement is preceded by a slide with the number 7, then they

would circle T or F for number 7 on the SJT answer sheet.

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There were a total of 87 statements in the SJT, and 14 of

these statements were target statements. For subjects in the

“clues” conditions, 3 of the 14 target phrases contained clues to

the riddle. For example, for the riddle stated above, subjects

in the clues condition encountered the statement: Bicycle is a brand of

playing cards. Alternatively, if it was a no clue condition the

clue was replaced with the statement such as, Marlboro is a brand of

cigarettes (Appendix F).

Follow-up Questions. Follow-up questions were given as a

final task before debriefing (Appendix G). These questions were

to assess if participants thought about the riddles during the

incubation period and to find if the subject had ever seen any of

the riddles before. A question was also used to find if the

participants noticed that there were clues to the riddles within

the SJT. This was the last task before a debriefing form was

handed out (Appendix H).

Procedure

Assessing Riddles for the Study. Before beginning the actual

incubation study, a pool of riddles was obtained from other

studies and from the internet. These riddles were given to an on-

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line psychology class and then riddles, in terms of their

difficulty, were chosen. One extremely difficult and two

moderately difficulty riddles were picked. Riddle difficulty was

assessed by the proportion of riddles solved and unsolved by the

online psychology class.

The Study. Research took place in a classroom on EKU’s

campus. Sessions included 1 to 5 subjects per individual

session. The sessions were divided into three phases (except for

subjects in the no-break group).

Phase 1. As subjects arrived, they were told to sit at a

desk with an empty folder. They were then told that they would be

solving some riddles and also completing a sentence judgment

task; further they were told that as the study progressed they

would be asked to place each completed form into the folder.

Participants were then read the consent form and asked to silence

their cell phones and turn off any other type of distracting

devices since interruptions could interfere with the experiment.

After gaining consent, a riddle booklet and answer sheet was

provided to each participant. Subjects were then told that on

each page they would see a riddle, and that they should write any

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solution next to the corresponding number on their answer sheet.

Then, participants were instructed that if they were able to

provide an answer, raise their hands and then the researcher

would come to verify their answer. In order to verify an answer,

the researcher held up a “yes” or “no” card. The “yes” card

indicated that their answer was correct and that they should sit

and await further instructions. A “no” card indicated that the

answer was incorrect and that they should continue working on the

riddle. This was necessary to control for guessing at the

riddles.

Subjects in all groups except the no-break group had two

minutes per riddle and were told that they should not turn the

page in the booklet until instructed to do so. Following these

instructions, a timer was set for 2 minutes and the participants

were told to begin. After two minutes the experimenter told the

subjects to stop and turn to the next riddle. After all the

riddles were completed in this sequence the subjects were told to

place their answer sheet into the folder while the researcher

collected the riddle booklets. The no-break group was given four

minutes to solve each riddle but did not participant in any

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further phases. After completion of the riddle task, subjects in

the no-break group were debriefed and dismissed. In all other

conditions, participants continued on to phase two.

Phase 2. During this phase subjects were either introduced

to a clues-task or a no-clues task. For both tasks, subjects

were simply asked to judge the truth of some statements. At the

beginning of this phase subjects were told that they would be

seeing some statements and would need to judge whether some of

the statements were true or false. The researcher then handed

out a sentence judgment task answer sheet. For the task,

participants were instructed to make the judgment about a

statement that was presented after a slide with a number. So, if

a statement was presented after a slide with only a number, then

they judged whether it was true or false by circling T or F next

to the appropriate number on their answer sheet. The procedure

was identical for subjects in the no-clues group. The task was

approximately 10 minutes in length and after, participants were

instructed to place the forms into their folder.

Phase 3. Subjects were told that they would now have a

second chance to solve the riddles. The researcher then handed

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out the same riddle booklet from the beginning of phase 1 along

with a new answer sheet. They were then told that they would

again have two minutes to offer a solution to each riddle.

However, this time no verification of answers would be provided

because any new answer immediately following incubation would be

indicative of whether or not an incubation effect was present. As

before, subjects were not allowed to proceed from one riddle to

the next until told to do so by the experimenter. After

completion of the riddles, subjects were asked to place all the

materials inside the folder and that next they would be answering

three “follow-up” questions, presented in the front of the room,

from a projector, similar to the sentence judgment task. Finally

subjects were given an explanation of the experiment and

dismissed (Appendix G).

Results

A One-Way ANOVA found a significant effect among conditions.

Each subject was given an “improvement score”. This was the

proportion of unsolved riddles that were solved at attempt two

but were not solved at attempt one. The proportion was highest in

the Clues condition, F(2, 74) = 5.6, p = .005. A Bonferroni test

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showed that the Clues group significantly differed from the

Control group. No other differences were significant.

Discussion

The present study examined to find if taking a break from an

unsolved problem helps trigger sudden insight into a problem’s

answer. Moreover, this study looked to find if information

encountered during a break is relevant in helping facilitate

sudden insight versus no relevant information being present

during the break. It was found that when relevant information to

an unsolved problem is found within the environment, it can be

recognized, and used to help trigger sudden insight.

Some studies have found that simply taking a break during

problem solving can help trigger sudden insight into an unsolved

problem. However, as one meta-analysis showed, inconsistencies

with systematic facilitation of incubation effects are observed

with rest alone (Sio & Ormerod, 2009). While Baird and collogues

(2012) found that an undemanding task may promote mind-wandering

and lead to incubation effects, the nature of a task may be

called into question.

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Some believe the nature of the task given during incubation

may be the influencing factor of sudden insight. Segal (2004)

explained that a demanding task might help an individual break a

false assumption about the problem while Baird and collogues

(2012) found that an undemanding task may help an individual’s

mind wander and allow for more insight into specific types of

problems. One difference between these two perspectives was how

variables were operationally defined. While Segal (2004) examined

mathematical problems, Baird et al (2012) looked at word

generation problems. Inconsistencies within the literature may be

reflective of how variables are defined as with these two cases.

Theoretically, it may not be the type of task that is used during

incubation that is effective, but instead be the type of

information included within the task.

Dodds, Smith, and Ward (2002) found little support for the

OA theory of incubation and instead suggested that participants

show more improvement when explicitly instructed to look for

clues pertaining to an unsolved problem during the incubation

phase. However, one possible confound that was uncontrolled for

during this study was how participants’ guessing during the

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initial preparatory stage might affect predictive encoding, thus

interfering with the recognition of relevant information from the

environment during incubation. During a preliminary stage of the

present study, it was observed that participants hardly

recognized potential relevant information during incubation like

observed with Dodds, Smith, and Ward (2002). It is believed that

this was due to the participants guessing at the riddles during

the initial encounter with the problem task. However, when

guessing was controlled for by adding a verification procedure to

the initial riddle task, (i.e. participants being instructed that

their initial answers were correct or incorrect), participants

were more likely to recognize relevant information added to the

incubation phase such as the clues, without being instructed to

do so. Future research should explore the potential benefits of

controlling for guessing during the study of incubation.

It makes sense that guessing at an initial attempt with a

problem solving task might interfere with processes of predictive

encoding. Predictive encoding may be a process in which unmet

goals or unsolved problems are encoded to long term memory

awaiting interaction with a cue relevant to the goal or problem

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being solved. If an individual’s goal is to answer a riddle, and

then they guess at the answer, then no further resources may be

directed towards the question, thus hindering predictive

encoding. This seemed to be the case with the present study. It

was observed that as the participants guessed at a problem, they

would merely sit quietly looking around the room or draw doodles

on their answer sheet while awaiting instructions to turn to the

next question. Most often, during the second phase of the

preliminary study, almost no one recognized the clues to the

riddles. However, once guesses were verified, it was if the

participants persisted upon the questions more intensely, thereby

leading them to recognize clues to the riddles during the second

phase of the study.

Also it has been suggested that as the number of open goals

increases in memory (in this case, the number of unsolved

problems), then the ability to recognize relevant information

associated with those goals diminish (i.e. failure to notice the

clues) (Moss, Kotovsky, & Cagan, 2007). This may be a factor of

interest for future research as well. One study found that by

using 20 different problems, improvement during incubation

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correlated with the amount of time spent on the problem (Smith &

Blankinship, 1989). It would be interesting to find if

improvement scores would still be affected if the amount of

problems were modified to include fewer problems.

Essentially, incubation is a highly variable effect that can

rely upon multiple factors during problem solving. These factors

can include the types of problems being used, the duration of the

preparatory and incubation stages, and elements of the problem(s)

used during the preparation and incubation stages. An ideal study

examining incubation might include a preparation stage with

veridical-type problems (i.e. problems with only one answer),

include enough time for predictive encoding to take place

(assuming this is known), control for guessing with verification

during the preparatory stage, and include information relevant to

an unsolved problem during the incubation phase. It may also be

important to examine the stage after incubation to find if time

may be an influencing factor of recall and sudden insight. This

study only counted the first answer provided by participants

during the second attempt with the riddles. One last possibly

overlooked feature of importance when it comes to the study of

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incubation may be prior knowledge of the task. It would make

sense that it be necessary for individuals to possess some type

of relevant knowledge pertaining to a problem, if any type of

incubation effect is to be expected. Assuming that sudden insight

is a feature of the mind alone, born of its organizational

skills, automatic or intentional, ironically triggers the notion

that knowledge is an innate ability of everyone. In some way,

this assumption may suggest that each and every individual

already possesses the answer(s) to any question as long as there

is something relevant within the environment that can trigger the

correct organization of sudden insight.

Email kevin_smith202@mymail.eku.edu for appendices.

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