This article was downloaded by: [Universita di Padova]On: 31 October 2013, At: 01:32Publisher: RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK

Neurocase: The Neural Basis of CognitionPublication details, including instructions for authors and subscription information:http://www.tandfonline.com/loi/nncs20

Names and identification: An access problemCarlo Semenza a , Marina Zettin b & Francesca Borgo ca Department of Psychology , University of Trieste, Via dell'Universitá , 7 34123b Presidio Ospedaliero Ausiliatrice , Trieste, 10143c Cognitive Neuroscience Programme SISSA , 34014, Trieste, ItalyPublished online: 17 Jan 2008.

To cite this article: Carlo Semenza , Marina Zettin & Francesca Borgo (1998) Names and identification: An access problem,Neurocase: The Neural Basis of Cognition, 4:1, 45-53, DOI: 10.1080/13554799808410606

To link to this article: http://dx.doi.org/10.1080/13554799808410606

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) containedin the publications on our platform. However, Taylor & Francis, our agents, and our licensors make norepresentations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of theContent. Any opinions and views expressed in this publication are the opinions and views of the authors, andare not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information. Taylor and Francis shall not be liable forany losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoeveror howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use ofthe Content.

This article may be used for research, teaching, and private study purposes. Any substantial or systematicreproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Neurocuse (1998) Vol. 4, pp. 45-53 0 Oxford University Press 1998

Names and Identification: An Access Problem

Carlo Sementa, Marina Zettin’ and Francesca Borgo2

Department of Psychology, University of Trieste, Via dell’UniversitA, 7, 341 23 Ttleste, ‘Presidio Ospedaliero Ausiliatrice, 10143 Torino and 2Cognitive Neuroscience Programme, SISSA, 34014 Trieste, Italy

Abstract

This is a report about a patient, CB, who, as a result of brain damage, could not access semantic information about individuals unless given their names, which, however, he could not produce. It is proposed that CB’s previously unreported pattern of symptoms results from multiple functional disconnections isolating the collection of identity-specific semantic information from: (1) the corresponding phonological form, hence proper name anomia; (2) face recognition units, preventing faces being named and matched to semantic information; (3) general semantics, preventing the elements of a definition referring to an individual eliciting further individual specific information. The case is discussed together with similar cases and relevant theories that recently appeared in the literature. The peculiar role of persons’ proper names in the semantic system is highlighted. Unlike common names, which denote categories, proper names are thought to just label unique sets of casually clustered attributes constituting a person’s identity-specific semantics.

Introduction The production of proper names, a necessary part of social communication, has gained the attention of neuro- psychologists in the past decade. Relevant neuropsycho- logical studies show, in most cases, a selective difficulty with proper names, but there are cases. though less clear and fewer in number, whereby proper names are relatively spared with respect to common ones (see, for reviews, Cohen and Burke, 1993; Semenza et nl., 1995; Valentine et al., 1996; Semenza, 1997). The origin of proper name anomia has been attributed (Hittmair-Delazer et al., 1994; Bredart et al., 1995; Hanley, 1995) to functional lesions lying at the access to intact phonological (and maybe graphological) output representations from an intact semantic memory. More precisely, within models of lexical access such as that popularized by Levelt (1989), proper name anomia is said to result from damage at the level of the component, called the ‘lemma’, that provides an interface between the conceptualisemantic system and the phonological representation (the ‘lexeme’) of a single word. At this level ‘The semantic information . . . specifies what conceptual conditions have to be fulfilled in the message for the lemma to become activated: it is the lemma’s meaning’ (Levelt, 1989, p. 188). Lemmas also specify syntactic properties. These include the grammatical class: therefore, for example, the information that a given word is a noun and not a verb is conveyed at the lemma level. However,

even within the category of nouns there are important distinctions. Noun lemmas, indeed, fall into two major grammatical classes (Levelt, 1989): proper nouns and com- mon nouns. Hittmair-Delazer ef al. (1994) proposed that proper names anomia damages, from this level onward. the activation of the proper noun class only. According to their theory, two different patterns in the organization of semantic information lead to two mechanisms of activation at the lemma level, one for each class of nouns. This functional architecture would allow the possibility for brain damage to produce a selective deficit of one of the two mechanisms, that for proper names being intrinsically more fragile.

Hittmair-Delater et al.’s (1994) theory is now widely shared, on the basis of experimental studies on normal subjects (see Valentine et nl., 1996, for a complete review and new proposals): whether or not the whole of the lemma theory in itself is accepted is irrelevant for the present issues; here and in the discussion, the ‘lemma’ function just designates the collection of semantic and syntactic informa- tion that activates the phonological form. The nature, however, of the difference between two supposedly separate retrieval mechanisms is still poorly understood. It is not clear, for instance, whether the two mechanisms work in the same or in different ways. The recognition processes of different sources of input (faces, definitions, written or

Correspondence 10: Professor Carlo Semenza. Dipartimento di Psicologia, Universiti degli Studi di Trieste, Via dell’Universit8, 7, 34 113 Trieste. Italy. Tel: +39 40 676 7316/31; Fax: +39 40 312272: e-mail: semenza@univ.trieste.it

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

46 C. Semenza, M. Zettin and F. Borgo

spoken names, etc.), their interrelations and their relation to the retrieval of corresponding proper names are likewise obscure. Some of the available data are hard to reconcile with each other.

The case is studied here of a patient, CB, who features an unreported pattern of disorders in the processing of proper names, faces and the corresponding semantic information. A theoretical model integrating these functions will be proposed on the basis of the behaviour shown by CB and other, recently described, neuropsychological patients.

Clinical report CB, a 25-year-old right-handed worker, with 8 years of education, suffered a head trauma as a consequence of a road accident. A CT scan showed two small areas of hypodensity, the first in the left anterior frontal lobe and the second between the left parietal and occipital lobes. He was in a coma for 20 days. When he recovered he showed fluent speech abilities, notwithstanding a certain degree of dysarthria, and an anomia that was particularly severe for persons’ names. He was sent for our evaluation in 1993, 6 months after the trauma, because he complained of anomia for the names of people.

The present study took place in two stages: in late 1993 to early 1994 and in March to April 1997, when we could retrace him and test him again over most of the same tasks.

The first time we met him his dysarthria was still detectable but neither this symptom nor the anomia signifi- cantly affected what tended to be slightly logoreic but grammatically correct speech. His auditory comprehension and repetition were virtually perfect, as evidenced by currently used aphasia batteries (Aachen Aphasia Test-AAT) and so were his reading and writing. His digit span was 6 (3 backwards), his verbal span with bisyllabic words was 5 and his spatial span (Corsi’s test) was 7. He showed mild difficulties in learning supraspan lists of words. His memory for short stories was good, and so was his memory for autobiographical facts and his recollection of public events where the retrieval of persons’ names was not concerned. He had minor difficulties due to perse- veration with the Wisconsin Card Sorting Test, but did not show other significant signs of frontal lobe impairment. He did not show any sign of either visual agnosia for objects and pictures of objects (Benton’s Visual Form Discrimination Test) or of spatial disorientation.

An important aspect of CB’s case was his good performance with faces. Two tasks were administered: familiarity judgements and ‘face recognition’. The familiarity judgement test required our subject to decide which face out of two, matched for age, sex and general perceptual features (like dark versus pale colour, large versus small mouth, etc.), belonged to a famous person. CB had no difficulty with this task, which he performed correctly for 70/70 items. This task was not given the second time. In order to assess whether poor perceptual

processing or poor memory for faces played any role in CB’s problem (a rather unlikely possibility, given his preserved ability to make familiarity judgements on faces) he was administered (on the first occasion) Warrington’s face recognition memory test (1984). His score (43150) was well within normal limits.

Four years later CB’s general neuropsychological assess- ment did not reveal any important variation except for the disappearance of dysarthria and for a performance with the Wisconsin Card Sorting test that was within normal limits.

Experimental investigation Before describing CB’s performance (summarized in Table I), it is perhaps useful to discuss briefly the strategy in testing neuropsychological patients on their knowledge of proper names. Both common sense and preliminary investigations told us that knowledge of proper names varies across subjects in a much wider way than with common names. In fact, knowledge of proper names is much more subject to episodical experience and to a person’s interest in a certain domain. Thus, if someone is not interested in sports (or in politics, history, etc.) he/she may ignore the names of personages who are very much talked about by other people. This must be taken into account for a test of proper names to be used for clinical purposes on a single subject. In this case it appears necessary to resort to items representing only extremely famous characters, i.e. those known, at a certain period of time and within a certain culture, by virtually 100% of the healthy adult population, conceding only for momentary lapses of memory. Except for a few historical figures most of the items must be changed over the years because fame is subject to oblivion, physical features also change (pictorial material has thus to be renewed) and so do biographical facts. The choice of geographical items has similar though not entirely overlapping problems. This leaves very few good items, especially for visual confrontation naming.

T h e material used for testing CB on proper names the first time differs from the material used 4 years later: all pictures (including those of historical characters) were changed, even if most of the portrayed people remained the same. Descriptions of contemporary personages were updated, and some previously not famous people were included. The first proper name battery was such that no normal control committed more than two errors in each subtest and all items were named correctly by more than 95% of the controls. The second proper name battery included a few more items and was slightly more difficult. The mean performance of 60 normal controls aged 20-30 will be indicated for most of the tasks; for other tasks, constructed just for this study (i.e. name-picture matching and retrieval of person-specific information) five control subjects with exactly the same age and education as CB were used.

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

Names and identity 47

Table 1. CB’s performance in the experimental investigation, expressed as percentage correct

Common names and facc processing First session ( 1993-94)

Second session (1 997)

Boston Naming Test AAT Miceli er ul. (1994) battery (objects and actions) Naming from Definition (objects) Face Familiarity Judgements Warrington’s (1984) Face Recognition Memory Proper numes-specific Iasks Picture naming on visual confrontation

Naming from definition

Retrieval of person-specific information

Name-picture matching task

People Geographic:

Italian cities European cities

People Geographic From a given name:

People From a given definition:

People People Geographic:

Pictures Blank atlas

68.3’ 90.

100 90

100 86

6.2*

70*

21.8* Not administered

Not administered

93.7

0. 2 I .8*

Not administered 100

8 1.6* 100 100 100 Not administered Not administered

1 O*

40* 25’

60*

87.5

7.5*

O* 44.4*

87.5 Not administered

*Pathological performance.

Naming of objects and actions In visual confrontation naming via the Boston Naming Test CB scored 41/60 (49/60 with phonemic cueing) the first time and 49/60 (no improvement with phonemic cueing) the second time (it may be important to add that, in strict accordance with the instructions, the test was suspended when the patient failed six items in a row); in other, less demanding, naming tests, such as those of the AAT battery, CB’s score was close to 90% correct the first time and perfect the second time. The first time he failed only the most difficult items and provided full information about the target, including both functional and structural features when he could not retrieve the name. With the Miceli et of. (1 994) battery, which includes naming of pictures of both objects (40 items) and actions (32 items), CB’s performance was 100% correct both times. In naming of objects from definition he scored 36/40 the first time and 40/40 the second time.

Proper name-specific tasks In sharp contrast with his relatively mild difficulties with naming objects and actions CB could not retrieve, either by speaking aloud or by writing, real people’s names (except for his own), including those of his wife and his son. This impairment persisted unvaried 4 years later, except for the names of his wife and son which he had relearned.

Real people presented him with another problem: he could easily tell if he knew a person, but he could not clearly distinguish individuals if unaided with clear con- textual cues. For instance, he could never decide at first sight who was who among the psychologist and two speech

therapists, all women of roughly the same age, size and hair colour. Only when they spoke their names did he seem to recollect all the information he possessed about each of them.

CB could correctly read and write on dictation all proper names, including those with irregular orthography.

Picture naming The first time CB was shown a series of 32 pictures of famous people (including historical as well as more or less contemporary people), he could only retrieve the names of two of them and said ‘I do not know’ in all other cases. Phonemic or semantic cueing did not help him in this case and he could not provide, on the basis of photographic material only, any type of information. The ability to re- trieve geographical names was tested using a blank atlas: he correctly named 14/20 map sites. Though pathological, this performance seems better than that with persons’ names.

Four years later CB retrieved 4/40 (10%; normal con- trols: 91.3%, SD 7.46) names of people (in photographs), and 4/10 names (40%; normal controls: 90.1%;SD 8.53) of famous cities (in photographs). Cueing was still not helping his performance. On a blank atlas he named 7/15 Italian cities (46.7%; normal controls: 68.5%; SD 14.06) and 3/12 (25%; normal controls: 66.91%; SD 17.66) European cities.

Naming of people was tested again after an interval of 2 weeks: this time the pictures were intermixed with other pictures of famous people that had not appeared 2 weeks earlier. CB was only able to name the four items he had correctly retrieved the first time but could tell which pictures he had been given 2 weeks earlier and which ones were new.

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

48 C. Semenza, M. Zettin and F. Borgo

Naming from definition only 7/32 cases. Four years later he was successful on 5/18 - In naming people from definition, CB was just slightly better than in visual confrontation, scoring 7/32 for famous persons. Again phonemic cueing was of no help. If a person’s name had a real meaning (for instance, Columbus-Colombo in Italian means ‘pigeon’) CB was also cued to this meaning (e.g. he was told: ‘tell me who discovered America; his name is that of a bird’): his performance, however, did not improve (1/15). Four years later he scored 3/40 in naming people from definition (7.5%; normal controls: 95.1%; SD 6.24), getting no help from phonemic cueing. In naming cities from definition he scored 6/10 (60%; normal controls: 98.6; SD 2.95).

Naming by category Naming by category in 1 minute was also tested. In this case CB provided the names of nine trees, nine fruits, seven vegetables, 12 pieces of furniture, 10 toys, nine birds, nine sports, seven carpenter’s tools, seven weapons and nine means of transportation. In the same time limit he was able to generate five names when ‘any person’s name’ was requested, but his performance dropped when more delimited categories were asked (two politicians, one sportsman, one actor). Typically, unlike in normals, additional time did not improve his performance with proper name categories, whereas for all other categories he continued to give new correct items. Four years later CB provided the names of two sportsmen, two politicians, no actors, no singers, five Italian cities and three foreign cities. Mean values from normal controls for these categories were: sportsmen: I 1 .OO (SD 4.44); politicians: 10.27 (SD 3.94); actors: 6.70 (SD 2.96); singers: 10.21 (SD 4.23); Italian cities: 19.85 (SD 4.21); foreign cities: 12.39 (SD 3.58). Again, for all these proper name categories he did not profit from additional time.

Repetition CB was able to repeat immediately any person’s name and to retrieve it if allowed to rehearse it silently without interference. Any interference procedure (such as counting backwards), however, caused his performance to drop to zero in 20 s (this was formally assessed with 20 surnames of famous people). This performance remained the same after 4 years.

Name-picture matching CB’s deficits with people’s names was not entirely limited to the output level. In matching spoken (or written) famous persons’ names to corresponding pictures in a multiple- choice test (eight alternatives, all faces of famous persons of the same sex and, possibly, from the same professional category, were provided for each item) he was successful in

items with persons and 14/16 items with names and pictures of cities (five control subjects did not make any error in these tasks). In contrast he scored 20120 in matching spoken names with map sites on a blank atlas on both occasions.

Retrieval of person-specific information In the course of naming famous people from definition, CB was specifically invited to provide any further distinguishing information he could recollect about both the physical appearance and the biography of the persons he could not name. In this condition, his score was nil (0/32); in no case could he do better than provide generic responses: for instance, if provided with the definition ‘the current prime minister’ he might say ‘Christian Democrat’ (an easy guess at the first period of this investigation) but not ‘black-haired’, or, in response to the cue ‘the Neapolitan actress who starred in La Ciociara or Matrimonio ull’italiana’ he would say ‘very beautiful’, but not that a few years ago she had to go to prison for tax evasion or similar personal information. He wds at all times reminded, also with examples, of the requests of this task (i.e. that the information had to be person-specific) and there is no doubt he understood the point but he remained none the less vague or frankly puzzled. When given the same task with definitions of common names (32 items) he had no problem whatsoever in adding further information. A11 sorts of information was provided fluently, with no difficulty whatsoever by CB, in response to people’s names. In this condition (i.e. when asked ‘tell me all you know about Mr X’, in contrast to ‘tell me all you know about the Prime Minister’) he could provide specific details, including physical features and biographical information, about 30132 famous persons. This pattern of performance was rather constant over the entire period of this investigation, appearing also in less formal testing and everyday life situations, with the possible exception of information con- cerning close relatives (occasionally he could correctly answer questions like ‘tell me your brother’s job’). Indeed, on the second time of testing CB could never add any information to the 40 definitions he was provided with, just declaring that he had a strong sense of familiarity for most of the targets (in this task five age- and education-matched control subjects provided the name and extra information for almost all the items-mean 37.5). Again, when given the name, CB provided personal, specific information in 35/40 cases. This test was scored in a very conservative way: full score was given only if two independent judges, un- aware of the definition, could unambiguously identify the name of the person just on the basis of the subject’s description. The following examples may give further insight on the patient’s performance. CB could not tell the name of ‘the most famous Italian Opera tenor alive’ and, despite declaring that he certainly knew the person, he

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

Names and identity 49

could not report any other biographical information. When prompted with the name ‘Lucian0 Pavarotti’ however, he said ‘a singer, he recently left his wife for his much younger secretary’. Similarly when asked who was ‘the Italian TV anchorman married to the soprano Katia Ricciarelli’ he could not come up with either the name or further infor- mation. The name ‘Pippo Baudo’, however, elicited ‘TV character, Sicilian, he might wear a toupee, the Mafia blew up his villa a few years ago’.

Discussion

In summary, CB could not produce persons’ names in any testing condition and could not match names to corresponding faces. Also, he could not match semantic information to faces that he was, however, able to judge as familiar and whose features he had no difficulty in remembering. Finally, he could easily retrieve full infor- mation about a person when provided with solely a name, but not when other cues consisting of information specific to that individual was given. This pattern of performance was essentially stable over more than 4 years. While related clusters of symptoms involving proper names and face recognition have been described (Semenza and Zettin, 1988, 1989; De Haan et ub, 1991; Lucchelli and De Renzi, 1992; Harris and Kay, 1995;. Van der Linden et ( i f . , 1995; Verstichel ct o f . , 1996), this particular pattern has so far never been reported.

A useful framework for most of the discussion of CB’s case is the model of proper name processing proposed by Valentine et af. (see Valentine et af., 1996, for the most complete version and for the evolution from earlier versions, e.g. Valentine et ol., 1991). The case, however, has several aspects of interest, that, for the sake of sim- plicity, will be addressed separately. Different portions of Valentine ct uf.’s (1996) model will therefore be referred to according to the specific issues.

The first aspect on which CB’s case seems to be infor- mative, once interpreted in the light of other cases recently reported in the literature, is the recognition of names and faces in general and the locus of familiarity effects in particular. A second interesting issue is that of the storage and retrieval of identity-specific semantic infor- mation: CB’s case, it will be argued, seems easily to fit the predictions of Valentine et af.’s (1996) model. However, a proposal will be put forward regarding the specific working of mechanisms devoted to proper name retrieval as distinct from those used for common names. A final point about localization will also be made.

Recognition and naming of faces In order to discuss the theoretical implications of CB’s case properly, it is first necessary to provide an outline of the basic functional architecture that is believed to support the

processing of names and faces. According to all current theories, at the input side after the first visual or auditory analysis, modality-specific representations are accessed that provide recognition for the stimulus material. These representations can be viewed as analogous to lexicons, where previously experienced words are stored; indeed in the case of names the representation belongs to the lexicon (phonological or orthographic), perhaps distributed over two levels whereby the proper name word is first recognized as a word and then as a name (see Valentine et al., 1991 and 1996 on this issue); in the case of faces, the structural information about single faces is represented. All this information would then converge into a modality- independent portion of the semantic system devoted to representations of individual entities. Note also that names and faces are by no means the only stimulus material likely to be represented in such way, personal voices being another obvious type of such stimuli (other, fuzzier, representations may contain personal smell or tactile characteristics).

Different views are taken about the content of modality- independent representations. One view (Burton and Bruce, 1992) is that they are just modality-free gateways into semantic information (Person Identity Nodes, or PINS in the authors’ terminology). Their relation with the semantic/ conceptual system would, however, be mediated by a more complex sort of representation whereby personal informa- tion would meet with other pieces of knowledge (Semantic Identity Units or SIUs). Semantic Identity Units would contain, together with proper names themselves, all other information concerning individuals.

In other models (Bruce and Young, 1986; Valentine et ul., 199 l), modality-specific information coming from names and faces would converge into stores for the infor- mation concerning individual persons and possibly other individual entities. Their degree of dependence on the semantic conceptual system remained, until Valentine et af.’s 1996 model, unspecified (this issue will be specifically pursued later in this article).

A controversial point concerns the locus where familiarity judgements take place. The original theory (Bruce and Young, 1986) assumed separate familiarity decision mechanisms for each input modality. This theory was, however, argued against by Burton et nf. (1990): the demonstration that separate mechanisms are not necessary led them to the apparently more parsimonious conclusion that familiarity judgements would take place at the modality-free representations for individuals. In* this and subsequent works (Burton et af. , 1990; Burton and Bruce, 1992, 1993) these authors explicitly proposed that familiarity decisions are based on the recognition of the person rather than of the nume or thefuce. A neuropsycho- logical case, M.E., described by De Haan et al. (1991) seemed to support Burton and Bruce’s (1992, 1993; Burton et al.. 1990) arguments. This patient could not produce any correct semantic information to either face (like CB) or

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

50 C. Semenza, M. Zettin and F. Borgo

name (unlike CB), while she (again at variance with CB) could match faces to names of familiar people. De Haan et al. (1991) proposed that M.E.3 matching abilities could be explained by assuming that matching takes place at the level of Person Identity Nodes, in keeping with Burton and Bruce’s theory according to which PINs are simple inter- faces, devoid of information. This level would also be the place where M.E. could make correct familiarity judge- ments. M.E.’s problem would be explained with a blocked access from PIN to SIU. This interpretation, however, is not entirely supported by CB’s performance. CB, in fact, while being perfect at familiarity judgements, could not access any semantic information from faces, but he could access the same information easily from names: access to semantic information must therefore be modality-specific. Familiarity judgements would be made by separate decision mechanisms for each input modality: CB’s problems with faces are then explained by a disconnection between face recognition units, where he could make proper familiarity judgements, and the representation for identity-specific semantic information. Note that, on Burton et al.’s (1990) account, what happens at the level of ‘recognition units’, in particular at the face recognition level, is not clear (a structural description is claimed to be accessed, but which sorts of operations this representation would allow-and which not-remains unspecified) and it is indeed difficult to understand how recognition could take place without a sense of dijd YU or familiarity. However, it is perfectly plausible in the case of face recognition to view this level, in analogy with the lexicons (and with the ‘pictogens’, postulated for object visual recognition- Ratcliff and Newcombe, 1982), as the storing place for previously experienced visual information about individual faces. On this account M.E.’s ability to match names and faces while unable to provide other semantic information on individuals may be explained as a problem in reaching suprathreshold activation in the output from a specialized system containing such identity-specific information [which in terms of Bruce and Young’s (1986) model would be the PIN]. A similar explanation has been recently provided by Van der Linden et al. (1 995) in a developmental case where the only difference from CB was the patient’s ability to match names and faces. Van der Linden et al. (1995), however, pointed out that their observation was also compatible with Burton and Bruce’s (1992) model: a slight attenuation of the connections between face recognition units and PINs would not prevent PINs from reaching the threshold activation necessary for familiarity judgements, while activation would be insufficient for the output (on similar grounds, Valentine et aL’s 1996 model maintains the location of familiarity effects at the PIN level). Except for minor differences in activation level, Van der Linden et aL’s (1995) case seems very similar to CB. A critical similarity is the patient’s ability to retrieve all identity- specific information in response to names. Proper names seem to work like unique keys to elicit such information

that, at least in CB (where this was demonstrated), cannot be retrieved via other pieces of information.

The isolation of identity-specific semantic information In CB’s case identity-specific semantic information seems to be totally disconnected from the face recognition system and cannot activate the proper lexical output. It also seems to be cut off from other types of information and not retrievable as a whole without the cue provided by the corresponding proper name.

Valentine er ul.’s (1996) model can be used to explain this pattern. The area within the model that is of interest to this specific discussion, modified in order to emphasize some particular aspects, appears in Fig. 1. First, as for all proper name anomias described so far, a disconnection (no. 1 in the figure) between the lemma level and the phonological form (the lexeme) prevents proper names from being retrieved. Both Hittmair-Delazer ef al. (1994) and Hanley (1995) postulate that common and proper names enjoy separate lemma to lexeme activation, blocked for proper names only in proper name anornia. Another disconnec- tion, isolating face recognition units (no. 2 in the figure), prevents faces from being named or even matched to semantic information. Explaining why definitions do not activate other identity-specific semantic information is more problematic: however, mapping from general seman- tics, where components of a definition are presumably initially activated, into identity-specific semantic informa- tion is a distinct operation in Valentine et aL’s (1996) model (the disconnection resulting from failure of this activation is represented in the figure as no. 3). Thus the whole area encompassing proper names lemmas (including PINs, here represented as the collectors of identity-specific semantic information) and identity-specific information would be accessible, in CB, only via proper names in oral or written form. As shown in Fig. 1 (and anticipated in the discussion about modality-specific representations) other information like familiar voices may converge into this area: whether or not it gains access to it in CB cannot be told due to the lack of proper experiments.

Specific retrieval mechanisms for common and proper names The area that has just been described as functionally disconnected in CB does not necessarily have to be envisaged as a separate storage space. It may, instead, be seen as the locus of action of a computational device specific for the retrieval of proper names. This device would work, for the reasons reported above, at the lemma level, in parallel to the device devoted to common names. Both devices would have the specific function of lemmas, i.e. collecting from general semantics the specific information that is necessary to activate a precise name. However, the

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

Names and identity 51

DEFINITION

CoLLEcnON OF IDENTITY SPECIFIC INFORMATION

P E E x C

N O

Fig. 1. A model of proper name processing and CB’s deficit.

operation needed in the case of a common name would differ from that needed in-the case of a proper name according to the different nature of the two kinds of name.

According to psycholinguists (e.g. Jackendoff, 1983; Levelt, 1989) a pivotal difference between common and proper names lies in the fact that, while the former have ‘type’ reference, the latter have ‘token‘ reference. In other words common names designate categories, while proper names designate individuals. Starting from this fact some considerations may follow. A name designating a category applies to a set of attributes overlapping or interacting with each other via high-probability connections. Thus the attributes ‘furry’, ‘long tailed’ and ‘purse over the belly’, overlap each other via high-probability connections in so far as many furry animals have long tails, all marsupials are furry, etc. It is the degree of redundancy that enables a name, ‘kangaroo’, to define many exemplars, i.e. the members of the category ‘kangaroo’. Consider instead the set of attributes ‘president of the United States’, ‘plays the sax’, ‘fair-haired’, ‘married to a lawyer’. In this set, all the attributes combine together incidentally, since the probability of a ‘president of the United States’ ‘playing the sax’ is about the same as for everybody else of the same social class in North America etc. The operation of label- ling with a proper name is therefore specific to naming individual entities, whose attributes are related to each other only by virtue of belonging to entities that are unique. In the act of naming, names are thus activated either by attributes that have a high probability of being linked to each other (common names) or by attributes that happen to be linked together only incidentally (proper names).

This distinction resembles closely that universally made between semantic and episodic memory mechanisms but with an important difference: the mechanisms in question are more peripheral and operate at the lexical level. Indeed proper name anomics (e.g. Semenza and Zettin, 1988, 1989) have no problems in memory for events and, on the other side, forgetting of proper names in amnesia is not specific and is related to the degree of retrograde and anterograde amnesia.

This description also contains the reasons why retrieval of common names is more robust than retrieval of proper names: the collection at the lemma level of the attributes of a category is made easier by pre-existing high-frequency links. This idea is similar to that of Burke et al. (1991), essentially adopted by Valentine et al. (1996). Burke et al. proposed that common names (in ‘lexical nodes’) are directly activated by attributes in the semantic system (in ‘prepositional’ and in ‘visual concept’ nodes); proper names, instead, would be activated only indirectly, via a simple person identity node, which would make the process more fragile. The idea of a different mechanism, more fragile because no high-frequency links exist to help attribute collection, just dispenses with the necessity of postulating an intermediate node. It also explains one of the most peculiar findings in CB [and in Van der Linden et d ’ s (1995) patient]: that providing the name, i.e. the only common link, helps the bringing together and retrieving of all individual specific information.

Finally, this theory seems to capture within itself all explanations that have been proposed to account for the vulnerability of proper names, showing how, as told in

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

52 C. Semenza, M. Zettin and F. Borgo

Valentine et al. (1996) and in Semenza (1997), these explanations are all very similar. Indeed, concepts like meaninglessness, arbitrariness, pure reference, token reference, uniqueness may all be applied to the just described proper name retrieval mechanism.

Cerebral localization One last argument concerns the cerebral localization of proper name processing. CB’s case may be useful in under- standing what role the right hemisphere may play in this respect. It has been claimed with some empirical evidence (Wapner and Gardner, 1979; Saffran et al., 1980; Van Lanker and Klein, 1990) that the right hemisphere supports proper names recognition. CB’s case helps to clarify this issue: his inability to match names and faces comes from a lesion strictly limited to the left hemisphere. Specific linguistic mechanisms subserving proper name recognition are thus probably stored exclusively in the left hemisphere: the right hemisphere may, however, process stimulus qualities, like personal familiarity and emotional relevance (cf. Van Lanker and Klein) and help in recognizing proper names in so thr as they share these qualities.

Where in the left hemisphere proper names processing takes place is still unclear. While recent work from Damasio P I (11. (1996) seems to point unequivocally to the pole of the temporal lobe, the review of relevant literature (see Semenza et d., for update to 1995) induces much more cautious conclusions.

Acknowledgements We thank Richard Hanley, Tim Valentine and an anonymous referee for pointing out weaknesses in an earlier version. This study has been supported by grants from the Minister0 della Pubblica lstruzione and from Escape to Carlo Semenza.

References Brkdan S. Valentine T, Calder A. Gassi L. An interactive activation

model of face naming. The Quarterly Journal of Experimental Psychology 1995; 48A: 466-86.

Bruce V, Young AW. Understanding Face recognition. British Journal of Psychology 1986; 77: 305-27.

Burke DM. MacKay DG, Worthley JS, Wade E. On the tip of the tongue: what causes failures in young and older adults. Journal of Memory and Language 1991; 3 0 542-79.

Burton AM, Bruce V. I recognize your face but I can’t remember your name: a simple explanation? British Journal of Psychology 1992; 83: 45-60.

Burton AM, Bruce V. Naming faces and naming names: exploring an interactive activation model of person recognition. Memory 1993: 1: 457-80.

Burton AM, Bruce V, Johnston RA. Understanding face recognition with an interactive activation model. British Journal of Psychology 1990: 8 I : 361-80.

Cohen G, Burke DM. Memory for proper names: a review. Memory 1993; 1: 249-63.

Damasio H, Grabowski TJ, Tranel D, Hichwa RD, Damasio AR. A neural basis for lexical retrieval. Nature 1996; 380 499-505.

De Haan EHF, Young AW, Newcombe F. A dissociation between the sense of familiarity and access to semantic infomation concerning familiar people. European Journal of Cognitive Psychology 1991; 3: 51-67.

Hanley JR. Are names difficult to recall because they are unique? A case study of a patient with anomia. The Quarterly Journal of Experimental

Harris DM, Kay J. I recognize your face but I can’t remember your name: is it because names are unique? British Journal of Psychology 1995; 86: 345-58.

Hittmair-Delazer M, Denes G, Semenza C, Mantovan C. Anomia for people’s names. Neuropsychologia 1994; 32: 465-76.

JackendoH R. Semantics and cognition. Cambridge, MA: MIT Press, 1983.

Levelt WJM. Speaking: from intention to articulation. Cambridge, MA: MIT Press. 1989.

Lucchelli F. De Renzi E. Proper name anomia. Cortex 1992; 28 221-30. Miceli G. Burani C, Laudanna A. Batteria per I’analisi dei deficit afasici di

linguaggio. Roma: Universiti Crtttolica, 1994. RatcliB G. Newcombe F. Object recognition: some deductions from the

clinical evidence. In: Ellis AW, editor. Normality and pathology of cognitive functions. London: Academic Press, 1982.

Saffran EM, Bogyo LC, Schwiirtz MF, Marin OSM. Does deep dyslexia reflect right-hemisphere reading? In: Coltheart M, Patterson EK. Marshall JC, editors. Deep dyslexia. London: Routledge and Kegan Paul, 1980.

Semenu C. How names are special: neuropsychological evidence for dissociablc impairment and sparing of proper names. Knowledge in production. In: Campbell R, Conway M, editors. Broken memories: neuropsychological case studies. London: Basil Blackwell, 1995.

Semenm C. Proper names specific aphasias. In: Goodglass H, Wingfield A. editors. Anomia. New York: Academic Press, 1997.

Semenza C, Sgaramella T. Production of proper names: a clinical case study of the effects of phonemic cueing. Memory 1993; I: 265-80.

Semenza C. Zettin M. Generating proper names: a case of selective inability. Cognitive Neuropsychology 1988; 5: 71 1-21.

Semenza C. Zettin M. Evidence from aphasia for the role of proper names as pure referring expression. Nature 1Y89; 342: 678-9.

Semenza C. Mondini S. Zettin M. The anatomical basis of proper name processing. A critical review. Neurocase 1995; 1: 183-8.

Valentine T, Bredart S, Lawson R, Ward G. What’s in a name? Access to information from people’s names. European Journal of Cognitive

Valentine T, Brennen T. Bredart S. The cognitive psychology of proper names. London: Routledge, 1996.

Van der Linden M, Brdart S, Schweich M. Developmental disturbance of access to biographical information and people’s names: a single case study. Journal of the International Neuropsychological Society 1995; 1 :

Van Lanker D, Klein K. Preserved recognition of familiar personal names in global aphasia. Brain and Language 1990, 39 511-29.

Verstichel P. Cohen L. Crochet G. Associate production and comprehen- sion deficits for people’s names following left temporal lesion. Neurocase 1996; 2: 221-34.

Wapner W. Gardner H. A note on patterns of comprehension and recovery in global aphasia. Journal of Speech and Hearing Research 1979 29: 76S72.

Psychology 1995; MA: 487-506.

Psychology 1991; 3: 147-76.

589-95.

Warrington EK. Recognition memory test. Windsor: Nelson, 1984.

Received on 20 June. 1996; resubmitted on 16 June, 1997; accepted on 6 October. 1997

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3

Names and identity 53

Names and identification: an access problem

C. Semenza, M. Zettin and F. Borgo Abstract This is a report about a patient, CB, who, as a result of brain damage, could not access semantic information about individuals unless given their names, which, however, he could not produce. It is proposed that CBs previously unreported pattern of symptoms results from multiple func- tional disconnections isolating the collection of identity-specific semantic information from: ( I ) the corresponding phonological form, hence proper name anomia; (2) face recognition units, preventing faces being named and matched to semantic information; (3) general semantics, preventing the elements of a definition referring to an individual eliciting further individual specific information. The case is discussed together with similar cases and relevant theories that recently appeared in the literature. The peculiar role of persons’ proper names in the semantic system is high- lighted. Unlike common names, which denote categories, proper names are thought to just label unique sets of casually clustered attributes constituting a person’s identity-specific semantics.

Journal

Neurocase Reference Number:

Primary diagnosis of interest

Author’s designation of case

Key theoretical issue

Neurocax 1997; 4: 45-53

0102

Anomia for persons’ names and loss of identity-specific information

CB

0 Proper names may label unique sets of clustered attributes concerning a person‘s identity-specific semantics

Key ivortlr proper names; identity-specific information

Scan, EEG and related measures

Standardized assessment

Other assessment Warrington’s Face Recognition Test; Miceli, Burani and Laudanna Aphasia Battery; Boston Naming Test; Wisconsin Card Sorting Test

Lesion location

Lesion type

Language

CT scan

Aachener Aphasia Test

0 Left parieto-occipital and very small left frontal

Trauma

English

Dow

nloa

ded

by [

Uni

vers

ita d

i Pad

ova]

at 0

1:32

31

Oct

ober

201

3