Anomia for common names and geographical names with preserved retrieval of names of people: a semantic memory disorder

Successful use of the forced choice test for detecting concealment of semantic memory in criminal and intelligence investigations

The current study examined the validity of the forced choice test (FCT) in a forensic scenario when used to detect concealment of semantic memory (SM-FCT). We also compared the SM-FCT validity to the FCT validity in the more commonly investigated episodic memory scenario (EM-FCT). In simulating a scenario of investigating suspected members of a terror organization, 277 students were asked to deceptively deny being enrolled in a college in which they do actually study. Results indicated that the SM-FCT's validity level was within the range of the EM-FCTs' validity levels. Theoretically, the results support a cognitive-based explanation for the FCT operation mechanism. Practically, they imply that FCT can be used in criminal or intelligence investigations of suspected members of terrorist or criminal organizations or suspected perpetrators of illegal acts or acts of terrorism, in which the incriminating evidence being sought is in the realm of designated semantic memory or knowledge.

The central role of the left inferior longitudinal fasciculus in the face-name retrieval network

Unsuccessful retrieval of proper names (PNs) is commonly observed in patients suffering from neurological conditions such as stroke or epilepsy. While a large body of works has suggested that PN retrieval relies on a cortical network centered on the left anterior temporal lobe (ATL), much less is known about the white matter connections underpinning this process. Sparse studies provided evidence for a possible role of the uncinate fasciculus, but the inferior longitudinal fasciculus (ILF) might also contribute, since it mainly projects into the ATL, interconnects it with the posterior lexical interface and is engaged in common name (CN) retrieval. To ascertain this hypothesis, we assessed 58 patients having undergone a neurosurgery for a left low-grade glioma by means of a famous face naming (FFN) task. The behavioural data were processed following a multilevel lesion approach, including location-based analyses, voxel-based lesion-symptom mapping (VLSM) and disconnection-symptom mapping. Different statistical models were generated to control for sociodemographic data, familiarity, biographical knowledge and control cognitive performances (i.e., semantic and episodic memory and CN retrieval). Overall, VLSM analyses indicated that damage to the mid-to-anterior part of the ventro-basal temporal cortex was especially associated with PN retrieval deficits. As expected, tract-oriented analyses showed that the left ILF was the most strongly associated pathway. Our results provide evidence for the pivotal role of the ILF in the PN retrieval network. This novel finding paves the way for a better understanding of the pathophysiological bases underlying PN retrieval difficulties in the various neurological conditions marked by white matter abnormalities.

Exploring the Representations of Individual Entities in the Brain Combining EEG and Distributional Semantics

Semantic knowledge about individual entities (i.e., the referents of proper names such as Jacinta Ardern) is fine-grained, episodic, and strongly social in nature, when compared with knowledge about generic entities (the referents of common nouns such as politician). We investigate the semantic representations of individual entities in the brain; and for the first time we approach this question using both neural data, in the form of newly-acquired EEG data, and distributional models of word meaning, employing them to isolate semantic information regarding individual entities in the brain. We ran two sets of analyses. The first set of analyses is only concerned with the evoked responses to individual entities and their categories. We find that it is possible to classify them according to both their coarse and their fine-grained category at appropriate timepoints, but that it is hard to map representational information learned from individuals to their categories. In the second set of analyses, we learn to decode from evoked responses to distributional word vectors. These results indicate that such a mapping can be learnt successfully: this counts not only as a demonstration that representations of individuals can be discriminated in EEG responses, but also as a first brain-based validation of distributional semantic models as representations of individual entities. Finally, in-depth analyses of the decoder performance provide additional evidence that the referents of proper names and categories have little in common when it comes to their representation in the brain.

Proper names and personal identity

The present chapter reviews the body of knowledge acquired so far about the role of the temporal lobe in representing and processing proper names and individual identity information. This body of knowledge has been collected with the contribution of several methodologies, including neuroimaging, electrophysiological techniques, and, critically, clinical observations. All this evidence converges in showing that proper names and related information are processed in at least partially independent neural networks mainly placed in the anterior areas of the left temporal lobe. A description of the properties distinguishing proper names from common names is provided. These properties, it will be claimed, made a different anatomical organization necessary and, possibly, determined the evolution of the brain to support this advantageous distinction in meeting environmental demands.

Neural correlates of recognition and naming of famous persons and landmarks: A special role for the left anterior temporal lobe

The anterior temporal lobes (ATLs) have been shown to be crucial for recognition and naming of unique entities such as persons and places. In this chapter, we review previous research that identified the neural underpinnings of these processes, and discuss the convergence zone theory of conceptual knowledge and proper name retrieval. Lesion-deficit and neuroimaging studies have found that the temporal poles are essential for recognition and naming of unique persons and places. Research has shown laterality, in that the right anterior temporal pole is specialized for recognition and the left for naming. Here, we analyzed recognition and naming of persons and landmarks in a large neurologic sample (N=244) using the Iowa Famous Faces and Famous Landmarks tests. For both categories, education had a significant effect on recognition and naming performances, but age and gender did not. Lesion-symptom maps revealed lower naming scores for both Faces and Landmarks associated with lesions to the anterior and mesial left temporal lobe. Lower recognition scores were also linked to left temporal lobe damage, possibly due to the method we used for measuring recognition (verbally based). Overall, the results demonstrate the importance of the temporal lobes for recognition and naming of unique persons and places.

Naming famous people through face and voice: a normative study

OBJECTIVES

Within the large topic of naming disorders, an important and separated chapter belongs to proper names. Defects of proper naming could be a selective linguistic problem. Sometimes, it includes names belonging to various kinds of semantically unique entities, but other times, it has been observed for famous people proper names only. According to Bruce and Young's model, different stages allow to recognize, identify, and name famous people from their faces and voices, subsuming different anatomical pathways, both in right temporal lobe, and their different efficiency in this task. The present study aimed to report the normative data concerning the naming of the same famous people from voice and face.

SUBJECTS AND METHODS

One hundred fifty-three normal subjects underwent a test in which they were requested to name famous people from their face and from their voice. The stimuli belonged to the previously published Famous People Recognition Battery.

RESULTS

The mean percentage score on naming from face was 84.42 ± 12.03% (range 55.26-100%) and the mean percentage score on naming from voice was 66.04 ± 16.81% (range 28.13-100%). The difference observed in performance by face and by voice resulted significant (t|₁₅₃ = 15.973; p < 0.001). Regression analyses showed that the percentage score obtained on naming from faces was predicted by education, whereas naming from voice was predicted by education and gender.

DISCUSSION

Naming from voice is more difficult than from face, confirming a different difficulty of the two tasks. Education showed high predicting value for faces and less for voices, whereas gender contributed to predict results only for voices.

The Role of Semantic Gender in Name Comprehension: An Event-Related Potentials Study

It is well known that the semantic features of gender associated with peoples' names are represented in the conceptual semantic system. However, there is scant evidence that such knowledge plays a role in name comprehension, and if so, in which processing stage this occurs. The aim of this study was to provide evidence concerning the time course of the activation of semantic gender in the processing of people's names. We recorded event-related potentials when participants saw picture-name pairs. Compared with the gender congruent condition in which the priming picture and Chinese name were matched on gender, names in the gender incongruent condition showed a mismatch effect in the time windows of 300-500 ms and 500-700 ms. These findings illustrate for the first time the activation of semantic gender when processing people's names, and further specify that this access occurs in the stage of name recognition rather than person identification.

An Analysis of Famous Person Semantic Memory in Aging

BACKGROUND

In contrast to most memory systems that decline with age, semantic memory tends to remain relatively stable across the life span. However, what exactly is stable remains unclear. Is it the quantity of information available or the organization of semantic memory, i.e., the connections between semantic items? Even less is known about semantic memory for celebrities, a subsystem of semantic memory. In the present study, we studied the organization of person-specific semantic memory and its stability in aging.

METHODS

We designed a word association task based on a previous study, which consisted in providing the first word that came to the mind of the participants (15 participants for each age group 20-30, 40-50 and 60-70 years old) for 144 celebrities. We developed a new taxonomy of associated responses as the responses associated with celebrities name could in principle be very varied.

RESULTS

We found that most responses (>90%) could be grouped into five categories (subjective; superordinate general; superordinate specific; imagery and activities). The elderly group did not differ from the other two groups in term of errors or reaction time suggesting they performed the task well. However, they also provided associations that were less precise and less based on imagery. In contrast, the middle-age group provided the most precise associations.

CONCLUSION

These results support the idea of a durable person-specific semantic memory in aging but show changes in the type of associations that elders provide. Future work should aim at studying patients with early semantic impairment, as they could be different from the healthy elders on such semantic association task.

Temporal dynamics of access to amodal representations of category-level conceptual information

Categories describe semantic divisions between classes of objects and category-based models are widely used for investigation of the conceptual system. One critical issue in this endeavour is the isolation of conceptual from perceptual contributions to category-differences. An unambiguous way to address this confound is combining multiple input-modalities. To this end, we showed participants person/place stimuli using name and picture modalities. Using multivariate methods, we searched for category-sensitive neural patterns shared across input-modalities and thus independent from perceptual properties. The millisecond temporal resolution of magnetoencephalography (MEG) allowed us to consider the precise timing of conceptual access and, by confronting latencies between the two modalities ("time generalization"), how latencies of processing depends on the input-modality. Our results identified category-sensitive conceptual representations common between modalities at three stages and that conceptual access for words was delayed by about 90 msec with respect to pictures. We also show that for pictures, the first conceptual pattern of activity (shared between both words and pictures) occurs as early as 110 msec. Collectively, our results indicated that conceptual access at the category-level is a multistage process and that different delays in access across these two input-modalities determine when these representations are activated.

Some Unusual Neuropsychological Syndromes: Somatoparaphrenia, Akinetopsia, Reduplicative Paramnesia, Autotopagnosia

Some unusual neuropsychological syndromes are rarely reported in the neuropsychological literature. This paper presents a review of four of these unusual clinical syndromes: (1) somatoparaphrenia (delusional belief in which a patient states that the limb contralateral to a brain pathology, does not belong to him/her); (2) akinetopsia (cortical syndrome in which patient losses the ability to perceive visual motion); (3) reduplicative paramnesia (believe that a familiar place, person, object, or body part has been duplicated); and (4) autotopagnosia (disturbance of body schema involving the loss of ability to localize, recognize, or identify the specific parts of one's body). It is concluded that regardless of their rarity, it is fundamental to take them into consideration in order to understand how the brain organizes cognition; their understanding is also crucial in the clinical analysis of patients with brain pathologies.

The man who mistook his neuropsychologist for a popstar: when configural processing fails in acquired prosopagnosia

We report the case of an individual with acquired prosopagnosia who experiences extreme difficulties in recognizing familiar faces in everyday life despite excellent object recognition skills. Formal testing indicates that he is also severely impaired at remembering pre-experimentally unfamiliar faces and that he takes an extremely long time to identify famous faces and to match unfamiliar faces. Nevertheless, he performs as accurately and quickly as controls at identifying inverted familiar and unfamiliar faces and can recognize famous faces from their external features. He also performs as accurately as controls at recognizing famous faces when fracturing conceals the configural information in the face. He shows evidence of impaired global processing but normal local processing of Navon figures. This case appears to reflect the clearest example yet of an acquired prosopagnosic patient whose familiar face recognition deficit is caused by a severe configural processing deficit in the absence of any problems in featural processing. These preserved featural skills together with apparently intact visual imagery for faces allow him to identify a surprisingly large number of famous faces when unlimited time is available. The theoretical implications of this pattern of performance for understanding the nature of acquired prosopagnosia are discussed.

A Proposed Neurological Interpretation of Language Evolution

Since the very beginning of the aphasia history it has been well established that there are two major aphasic syndromes (Wernicke's-type and Broca's-type aphasia); each one of them is related to the disturbance at a specific linguistic level (lexical/semantic and grammatical) and associated with a particular brain damage localization (temporal and frontal-subcortical). It is proposed that three stages in language evolution could be distinguished: (a) primitive communication systems similar to those observed in other animals, including nonhuman primates; (b) initial communication systems using sound combinations (lexicon) but without relationships among the elements (grammar); and (c) advanced communication systems including word-combinations (grammar). It is proposed that grammar probably originated from the internal representation of actions, resulting in the creation of verbs; this is an ability that depends on the so-called Broca's area and related brain networks. It is suggested that grammar is the basic ability for the development of so-called metacognitive executive functions. It is concluded that while the lexical/semantic language system (vocabulary) probably appeared during human evolution long before the contemporary man (Homo sapiens sapiens), the grammatical language historically represents a recent acquisition and is correlated with the development of complex cognition (metacognitive executive functions).

Cerebral processing of proper and common nouns: Perception and production following left hemisphere damage

The goal of this study was to further investigate hemispheric specialization for proper and common nouns by examining the ability of individuals with left hemisphere damage (LHD) to perceive and verbally reproduce famous names and matched common names compared with the performance of matched healthy controls (HC). Ten individuals with LHD due to stroke and 16 age- and education-matched HC completed recognition and production tasks of famous proper and common nouns. All tasks were designed as split-visual field experiments, modelled after the study done by Ohnesorge and Van Lancker. Results contribute to a better understanding of hemispheric roles in perception and production of famous proper nouns, suggesting that (1) both hemispheres can recognize famous proper nouns, possibly due to a right hemisphere role in personal relevance and (2) production of proper nouns as well as common nouns is associated with left hemisphere.

Hemodynamic response in a geographical word naming verbal fluency test

Functional hemodynamic response was studied in a new Verbal Fluency Task (VFT) that demanded the production of geographical words while fMRI data was obtained. Participants completed 7 trials with a total duration of 2 min. 20 s. Four simple arithmetic subtraction trials were alternated with 3 geographical naming trials. Each trial had a duration of 20 s. Brain activity was contrasted between both conditions and significant differences (p < .05, Family Wise Error correction) were observed in the prefrontal medial gyrus, typically associated with word retrieval and phonological awareness, and in the parahippocampal gyrus, posterior cingulate cortex and lingual gyrus, areas related to spatial cognition. These results indicate that geographic VFT could be incorporated into a browser of cognitive processes using VFT considering its specific relationship with spatial cognition. Further investigations are proposed, taking special interest in the gender variable and eliminating phonological restrictions, because the evoked Argentinean cities and towns ended in a consonant letter.

Preservation of person-specific knowledge in semantic memory disorder: a longitudinal investigation in two cases of dementia

The double dissociation involving person-specific and general semantic knowledge is supported by numerous patient studies, though cases with preservation of the former are few. In this paper, we report longitudinal data from two cases. Their knowledge in both domains was preserved at the start of the investigation, but progressive deterioration was primarily observed on tests of general semantics. These data strengthen the evidence-base for preservation of person-specific knowledge in semantic memory disorder, and support its separate representation from object knowledge.

Why are names of people associated with so many phonological retrieval failures?

Two experiments are reported that revisit the issue of why people's names are more difficult to recall than common names such as the names of objects. In Experiment 1, retrieval of the names of a set of object pictures was compared with recall of a set of names of famous faces. The object and face sets were matched for preexperimental familiarity. The results showed significantly more tip-of-the tongue (TOT) states and significantly poorer name recall for faces than for objects. Although the overall numbers of incorrect answers for the two sets of items did not differ, the incorrect answers in the face condition were mostly "don't know" responses, whereas incorrect answers for objects were mostly alternative names. In Experiment 2, written definitions were used instead of pictures, and target items were selected so as to keep the number of alternatives to a minimum. Under these circumstances, there were no differences in either the number of items correctly named or the number of TOTs for common and people's names. These findings are consistent with the views of Brédart (Memory, 1, 351-366, 1993), who argued that there are fewer documented TOTs for common names because a semantically related alternative often comes to mind when a participant is experiencing, or is about to experience, a retrieval failure.

Recognition and naming of famous buildings: Italian normative data

Semantically unique items are concrete entities characterized by a unique cluster of semantic information. In this field, neuropsychology has always given more attention to faces than to other kind of stimuli. An important category that has been largely neglected so far is famous buildings. A total of 200 healthy Italian adults with age, sex and education homogenously distributed across subgroups were administered a famous buildings naming and recognition test, which assessed both visual and verbal modalities. The test was divided in seven sections; norms were calculated taking into account demographic variables such as age, sex and education. Multiple regression analyses showed that education influenced significantly the performance on all subtests; age had a significant effect for five subtests; sex for three subtests. Adjusted scores were used to determine inferential cutoff scores and to compute equivalent scores.

Manque du nom propre et effet de la modalité sur la capacité à reconnaître des personnes connues au cours du vieillissement normal

The aim of this study was to investigate the impact of aging on the ability a) to name famous faces and b) to access biographical knowledge about famous people from different modalities of presentation (faces and names). Healthy elderly subjects (n = 117) divided into three different age groups were assessed using a semantic memory test of famous people. Results of this study indicate a decline in naming performance between oldest and youngest groups. In contrast, no difference between groups was found in terms of the ability to access semantic knowledge about famous people. Finally, a main effect of modality of presentation (faces vs. names) was found, revealing greater ability to identify famous people in the verbal (names) than in the visual modality (faces). Taken together, results of this study may contribute to developing new cognitive intervention programs in older adults presenting with proper-name anomia.

How are 'Barack Obama' and 'President Elect' differentially stored in the brain? An ERP investigation on the processing of proper and common noun pairs

Background

One of the most debated issues in the cognitive neuroscience of language is whether distinct semantic domains are differentially represented in the brain. Clinical studies described several anomic dissociations with no clear neuroanatomical correlate. Neuroimaging studies have shown that memory retrieval is more demanding for proper than common nouns in that the former are purely arbitrary referential expressions. In this study a semantic relatedness paradigm was devised to investigate neural processing of proper and common nouns.

Methodology/Principal Findings

780 words (arranged in pairs of Italian nouns/adjectives and the first/last names of well known persons) were presented. Half pairs were semantically related (“Woody Allen” or “social security”), while the others were not (“Sigmund Parodi” or “judicial cream”). All items were balanced for length, frequency, familiarity and semantic relatedness. Participants were to decide about the semantic relatedness of the two items in a pair. RTs and N400 data suggest that the task was more demanding for common nouns. The LORETA neural generators for the related-unrelated contrast (for proper names) included the left fusiform gyrus, right medial temporal gyrus, limbic and parahippocampal regions, inferior parietal and inferior frontal areas, which are thought to be involved in the conjoined processing a familiar face with the relevant episodic information. Person name was more emotional and sensory vivid than common noun semantic access.

Conclusions/Significance

When memory retrieval is not required, proper name access (conspecifics knowledge) is not more demanding. The neural generators of N400 to unrelated items (unknown persons and things) did not differ as a function of lexical class, thus suggesting that proper and common nouns are not treated differently as belonging to different grammatical classes.

THE LEFT TEMPORAL POLE IS IMPORTANT FOR RETRIEVING WORDS FOR UNIQUE CONCRETE ENTITIES

BACKGROUND: The neuroanatomical basis of lexical retrieval has been studied intensively. The current review focuses on the special case of proper nouns. AIMS: This article reviews a program of research that has used both lesion-deficit and functional imaging (PET) approaches to investigate the neuroanatomical basis for lexical retrieval of proper nouns. In lesion-deficit studies, we found that damage to the left temporal polar (TP) region leads to reliable and specific impairments in naming famous persons (e.g., "George Clooney") and famous landmarks (e.g., "Golden Gate Bridge"). In functional imaging studies, we found that when participants name famous persons and landmarks, they produce specific activation (increases in regional cerebral blood flow) in the left TP region. MAIN CONTRIBUTION: These findings converge with lesion and functional imaging data from other laboratories to support the idea that the left TP region is important for the retrieval of names for unique concrete entities, persons and landmarks being typical examples of such categories of entities. CONCLUSIONS: We have interpreted these results within a theoretical framework that suggests that left TP contains convergence regions that operate as intermediaries between conceptual knowledge retrieval and lexical retrieval for classes of unique concrete entities.

Does maintenance of colour categories rely on language? Evidence to the contrary from a case of semantic dementia

Recent neuropsychological evidence, supporting a strong version of Whorfian principles of linguistic relativity, has reinvigorated debate about the role of language in colour categorisation. This paper questions the methodology used in this research and uses a novel approach to examine the unique contribution of language to categorisation behaviour. Results of three investigations are reported. The first required development of objective measures of category coherence and consistency to clarify questions about healthy control performance on the freesorting colour categorisation task used in previous studies. Between-participant consistency was found to be only moderate and the number of colour categories generated was found to vary markedly between individuals. The second study involved longitudinal neuropsychological examination of a patient whose colour categorisation strategy was monitored in the context of a progressive decline in language due to semantic dementia. Performance on measures of category coherence and consistency was found to be relatively stable over time despite a profound decline in the patient's colour language. In a final investigation we demonstrated that, for both the patient and controls, between- and within-participant consistency were higher than expected by (a) random sorting and (b) sorting perceptually similar chips together. These findings indicate that the maintenance of colour categorisation need not depend on language.

What can be localized in the brain? Toward a "factor" theory on brain organization of cognition

A theoretical integration attempt among the lesional (neuropsychological), physiological (functional), and psychometric models of cognition is presented in this article. Recent neuroimaging techniques particularly fMRI have shown that there are some brain functions (i.e., simple) that can be localized into single brain areas whereas there are others (i.e., complex) that cannot. Clinical neuropsychology has been able to propose some "cognitive factors" based on empirical observations in patients with brain lesions. Factor analysis in psychometry may provide an additional tool to extract some constitutive elements of psychological functions (factors). "Factors" in factor analysis, however, may have different levels of specificity. Some times they refer to functional systems (complex cognition); in other occasions to elements of cognition ("cognitive factors"). It is emphasized that the very same brain areas (and cognitive factors) may be potentially involved in different types of cognition. It is proposed that complex cognition depends on specific patterns of activation of different brain areas and specific circuitries ("modules"), each one making its own contribution to the whole system (functional system). Impairment in a specific cognitive factor, on the other hand, may result in diverse types of impairments. At the moment, it seems feasible to suppose some cognitive factors responsible for normal neuropsychological performance. Theoretically, the impairment in any of these factors could be responsible for some specific neuropsychological syndromes.

The associative processes involved in faces-proper names versus animals-common names binding: A comparative ERP study

Recognizing people involves creating and retrieving links between distinct representations such as faces and names. In previous research we have shown that the retrieval of face/name associations produced cerebral activities lateralized in the left hemisphere and spreading from posterior to anterior sites after about 300ms. The present ERP study was performed to compare the specific electrophysiological activities elicited by the retrieval of face/proper name (FP) and animal/common name (AC) associations. Using a subtraction method to isolate the specific binding activities, we showed that both kinds of association produced two main posterior negative/anterior positive complexes, with a more frontal distribution for AC, and bilateral temporal activities. These findings confirm that general associative processes - independent of the kind of association - are not simply the sum of the activities elicited by each stimulus, and that they could involve both unimodal sensory and multimodal convergence regions of the brain.

Proper and common names: a double dissociation

Proper name anomia and proper name sparing are unusual disorders characterized by a selective inability, or sparing, to retrieve proper names as opposed to common names. They may eventually demonstrate that these two categories of names are independently processed in the brain at the semantic or lexical/orthographic level. Yet, differences in patient assessment make comparison between cases difficult to interpret and raise alternative explanations to those dissociations, such as that they may be accounted for by the level of difficulty of test stimuli. We describe two individuals, of identical age, gender and cultural background, with a complementary pattern of impairment of name retrieval following a left hemisphere stroke. ACB had an aphasic disorder with impaired naming, sparing proper names, while JFJ had normal language abilities and semantic knowledge about people, but a marked anomia for people's names. Patients were studied using the same material, thus overcoming methodological constraints pointed to previous work. These cases provide evidence of a double dissociation between proper and common names at the lexical access level. In addition, JFJ had a normal ability to retrieve historical and religious names suggesting that either these names are less difficult to retrieve or that they may segregate within the proper name lexicon. Lesion of the left temporal pole was also dissociated. It was damaged in ACB but spared in JFJ, contradicting its crucial role in proper name processing.

Retrieval pathways for common and proper names

Paradigmatic cases of proper name anomia and proper name selective sparing are reviewed from relevant neuropsychological literature. Available evidence supports the existence of functionally and anatomically distinct retrieval pathways for the categories of proper and common names. An information processing model whose main feature lies in the relative independence within the semantic-conceptual system of information concerning individual entities may account for most of the observed phenomena. Localization studies seem to indicate that a complex neural network sustains various tasks implied in proper name processing. A dedicated module dealing with proper name retrieval is probably there, but its location within the left hemisphere is not at present fully understood. The proper name specific retrieval process is shown, in keeping with current philosophical and linguistic theories, to be intrinsically fragile and source-consuming.

A linguist's views on progressive anomia: evidence for Delbrück (1886) in modern neurolinguistic research

In his short paper of 1886, the neogrammarian linguist Delbrück sketches his views on normal language processing and their relevance for the interpretation of some of the symptoms of progressive anomic aphasia. In particular, he discusses proper name impairments, verb and abstract noun superiority and the predominance of semantically related errors. Furthermore, he suggests that part of speech, morphology and word order may be preserved in this condition. This historical document has been lost in oblivion but the original ideas and their relevance for contemporary discussions merit a revival.

Selective preservation of memory for people in the context of semantic memory disorder: patterns of association and dissociation

A number of single cases in the literature demonstrate that person-specific semantic knowledge can be selectively impaired after acquired brain damage compared with that of object categories. However, there has been little unequivocal evidence for the reverse dissociation, selective preservation of person-specific semantic knowledge. Recently, three case studies have been published which provide support for the claim that such knowledge can be selectively preserved [Kay, J., & Hanley, J. R. (2002). Preservation of memory for people in semantic memory disorder: Further category-specific semantic dissociation. Cognitive Neuropsychology, 19, 113-134; Lyons, F., Hanley, J. R., & Kay, J. (2002). Anomia for common names and geographical names with preserved retrieval of names of people: A semantic memory disorder. Cortex, 38, 23-35; Thompson, S. A, Graham, K. S., Williams, G., Patterson, K., Kapur, N., & Hodges, J. R. (2004). Dissociating person-specific from general semantic knowledge: Roles of the left and right temporal lobes. Neuropsychologia, 42, 359-370]. In this paper, we supply further evidence from a series of 18 patients with acquired language disorder. Of this set, a number were observed to be impaired on tests of semantic association and word-picture matching using names of object categories (e.g. objects, animals and foods), but preserved on similar tests using names of famous people. Careful methodology was applied to match object and person-specific categories for item difficulty. The study also examined whether preservation of person-specific semantic knowledge was associated with preservation of knowledge of 'biological categories' such as fruit and vegetables and animals, or with preservation of 'token' knowledge of singular categories such as countries. The findings are discussed in the context of a variety of accounts that examine whether semantic memory has a categorical structure.

Impaired naming of unique landmarks is associated with left temporal polar damage

Previous studies have shown that the left temporal polar (TP) region is important for the retrieval of proper names for persons. It has been proposed that the key specialization of left TP is for proper nouns (rather than names for persons, per se), which predicts that left TP should support other categories whose members are denoted by proper names (e.g., landmarks). A lesion study tested the hypothesis that impaired naming of famous unique landmarks would be associated with damage to left TP. A Landmark Recognition and Naming Test was administered to participants with lesions to left TP, right TP, or regions outside TP. The results provided strong support for the hypothesis: Landmark naming was significantly inferior in the left group, supporting the hypothesis. The findings converge with previous lesion and functional imaging data to support the idea that the left TP region is important for the retrieval of names for unique entities. This fits the proposal that left TP contains convergence regions that operate as intermediaries between conceptual knowledge retrieval and lexical retrieval for classes of unique stimuli (H. Damasio, D. Tranel, T. J. Grabowski, R. Adolphs, & A. R. Damasio, 2004).

Naming the Same Entities from Visual or from Auditory Stimulation Engages Similar Regions of Left Inferotemporal Cortices

We have proposed that the left inferotemporal (IT) region contains structures that mediate between conceptual knowledge retrieval and word-form retrieval, and we have hypothesized that these structures are utilized for word retrieval irrespective of the sensory modality through which an entity is apprehended, thus being “modality neutral.” We tested this idea in two sensory modalities, visual and auditory, and for two categories of concrete entities, tools and animals. In a PET experiment, 10 normal participants named tools and animals either from pictures or from characteristic sounds (e.g., “scissors” from a picture of a scissors or from the sound of a scissors cutting; “rooster” from a picture of a rooster or from the sound of a rooster crowing). Visual and auditory naming of tools activated the left posterior/lateral IT; visual and auditory naming of animals activated the left anterior/ ventral IT. For both tools and animals, the left IT activations were similar in location and magnitude regardless of whether participants were naming entities from pictures or from sounds. The results provide novel evidence to support the notion that left IT structures contain “modality-neutral” systems for mediating between conceptual knowledge and word retrieval.

A test for measuring recognition and naming of landmarks

There have been considerable giants in recent years in understanding cognitive and neural correlated for retrieval of various types of knowledge, such as the meanings and lexical forms for categories such as a familiar faces, animals and tools, and actions. An important category that has been largely neglected so far is landmarks, and one likely reason for this is a lack of suitable stimulus materials. Here, we report a study in which we designed a Landmark Recognition and Naming Test. The test contains 65 natural (e.g., "Old Faithful") and artifactual (e.g., "U.S Capitol") landmarks from around the world. Preliminary recognition and naming data about the participants (e.g., educational level, participants, experience traveling to national parks), the stimuli (e.g., visual complexity, image agreement), and participant-stimulus interactions (e.g., familiarity, age of acquisition), and analyzed how such factors influenced landmark recognition and naming. There was a pronounced sex-related difference in landmark recognition favoring men; however, men and women performed similarly in landmark naming. We provide here extensive data regarding the stimuli, and we encourage other investigators to make use of our stimuli and data in future investigations of landmark recognition and naming.

The categorical structure of semantic memory for famous people: a new approach using release from proactive interference

Memory for familiar people is essential to understand their identity and guide social interaction. Nevertheless, we know surprisingly little about the structure of such memory. Previous research has assumed that semantic memory for people has a categorical structure, but recently it was proposed that memory for people consists only of associations and lacks any categorical structure. Four experiments are reported that use a novel approach by adapting the 'release from proactive interference' (RPI) methodology for use with lists of famous names. Proactive interference occurs when items presented on successive trials are drawn from the same category. Recall can improve following a change to a different category. Sets of names were selected relating to aspects previously demonstrated, on the basis of reaction time data, to form a category (occupation) and a property (nationality) of celebrities (Johnston & Bruce, 1990). RPI was observed for a change at both levels of representation but was only present without explicitly cueing the change of set when the stimuli differed at the category level. At the property level, RPI was only evident when change of set was explicitly cued. RPI was absent at the set change in a novel, ad hoc distinction suggesting that the effect reflected the underlying memory structure.

Genetic components of vocal learning

Vocal learning is a rare trait. Humans depend on vocal learning to acquire spoken language, but most species that communicate acoustically have an innate repertoire of sounds that they use for information exchange. Among the few non-human species that also rely on vocal learning, songbirds have provided by far the most information for understanding this process. This article concentrates on the genetic components of vocal learning in humans and birds. We summarize the existing evidence for a genetic predisposition towards acquiring the species-specific human and avian vocal repertoires. We describe the approaches used for finding genes involved in shaping the neural circuitry required for vocal learning or in mediating the learning process itself. Special attention is given to a particular gene, FOXP2, which has been implicated in a human speech and language disorder. We have studied FoxP2 in avian vocal learners and non-learners and review evidence that links both the molecule and its close homologue FoxP1 to the development of brain regions implicated in vocal learning and to their function. FoxP2 has a characteristic expression pattern in a brain structure uniquely associated with learned vocal communication, Area X in songbirds, or its analogue in parrots and hummingbirds. In both avian song learners and non-learners FoxP2 expression predominates in sensory and sensory-motor circuits. These latter regions also express FoxP2 in mammals and reptiles. We conclude that FoxP2 is important for the building and function of brain pathways including, but not limited to, those essential for learned vocal communication.

Sparing of written production of proper nouns and dates in aphasia

Aphasia is a total or partial loss of the ability to produce or understand language, usually caused by brain disease or injury. In this case study, the aphasic patient (BMW) has a profound impairment of oral production and a very moderate impairment in comprehension. Several years of informal observation lead to the current study that contrasts written naming of common nouns to written naming of proper nouns and dates. BMW named professional ice hockey players, team logos, and provided birthdays of players with near perfect accuracy and normal rates of production. In contrast, his performance on naming common nouns was only 50% accurate and appeared very laborious. The results of this study thus show a clear preservation of date and proper noun production in contrast to common nouns.

Dissociating person-specific from general semantic knowledge: roles of the left and right temporal lobes

The cognitive architecture and neural underpinnings of different semantic domains remains highly controversial. We report two patients with focal temporal lobe atrophy who presented with contrasting and theoretically informative dissociations of person-specific versus general semantic knowledge. Subject J.P. showed severely impaired person-specific semantics, with relative preservation of knowledge about objects and animals, while subject M.A. exhibited the opposite pattern of performance (good knowledge of people in the context of impoverished general semantics). Voxel-based morphometric analysis of MR images in the two cases established predominantly right temporal atrophy associated with J.P.'s deficit for person knowledge and predominantly left temporal atrophy in M.A. who was impaired in general conceptual knowledge.

Anomia for people's names, a restricted form of transient epileptic amnesia

A 37-year-old man consulted after two episodes of transient anomia for people's names over a period of 6 months. The first episode lasted about 10 min and was restricted to an inability to remember his 2-year-old son's first name. The second, was limited to an inability to recall his daughter's first name for 5 min with clear abnormal experiential quality. Witnessed descriptions of the attacks confirmed the absence of any other cognitive impairment or motor automatisms. The neurological examination was normal except for hyposmia. Inter-ictal cognitive evaluation was normal apart from the anomia for people's names or retrieval of names of familiar people in his childhood on definition and on famous faces naming test. A wake electroencephalograph showed left temporal epileptiform abnormalities, following hyperpnea. On magnetic resonance imaging, quantitative analysis revealed a mildly decreased volume of the left hippocampus. The diagnosis of transient epileptic amnesia (TEA) was considered and the patient did not recur for 6 months under lamotriginum. Thus anomia for people's names may be the sole clinical manifestation of TEA. Such a clinical presentation may easily be overlooked. Treatment may prevent further recurrence and the installation of more important and permanent autobiographical memory impairment. Our observation may suggest an isolated system not only for people's knowledge, but for people's naming. It is consistent with the notion of proper name as pure referring expression.

Biographical Knowledge: Modality-Specific or Modality-Neutral?

A number of patients have been reported who produce more semantic information in response to faces than to names, and vice versa (e.g., Eslinger et al., 1996). It has sometimes been claimed that these patterns are consistent with the hypothesis that faces and names gain access to separate, modality-specific, biographic knowledge systems. Resolving this debate has proved somewhat difficult, however, given limitations of existing data. Not only are there relatively few patients showing these particular patterns of differentiation, but also testing has often not been sufficiently thorough to rule out alternative accounts. In this paper, we present results of two studies investigating biographical knowledge differences in neurological patients and healthy adult controls. The first study focused on two patients who appeared to access more information about famous people in response to their names than to their faces. On superficial analysis, this pattern could be seen to support the notion of modality-specific biographical knowledge systems. However, closer examination revealed that, for both cases, the findings could be explained by a difficulty in face recognition, rather than by assuming separate semantic representations for faces and names. The second study investigated the role of face and name cues in accessing biographical information in younger and older healthy adults. We found that accuracy in retrieval of biographical information was significantly better with name cues for both groups. Results from these studies not only highlight the processes that must be examined in order to demonstrate modality-specific differences conclusively, but also reveal a fundamental bias in retrieval of biographical knowledge that has not been addressed in research of this nature.

The semantic organisation of proper nouns: the case of people and brand names

We describe the performance of a patient (AZ) with a semantic refractory access disorder on a series of experiments probing comprehension of two broad proper noun categories, namely person names and brand names. By inducing and manipulating the semantic relatedness effects which are commonly observed in semantic refractory access patients, we demonstrate that famous person knowledge is primarily organised by occupation, whilst knowledge of brands is organised by product type. For instance, we show that AZ has significantly greater difficulty identifying a famous person from among distractor personalities who have the same occupation (e.g. composers: Beethoven, Mozart, Handel, and Bach) than those who have different occupations (e.g. Beethoven, Picasso, Shakespeare, and Jefferson). We also show that such semantic relatedness effects do not occur when stimuli are grouped by another variable such as nationality. We argue that these semantic distance effects reflect the greater build-up of refractoriness among concepts which are supported by shared neural circuitry. In psychological space, it seems natural that these individuals should be classified in this way. The strength of our findings lie in the fact that this organisation of psychological space is mirrored by neural organisation. Thus, we report a previously undocumented degree of fine-grain organisation within conceptual knowledge of these classes of proper nouns. We also interpret our data as providing the strongest empirical support to date for the semantic module of cognitive models of person recognition.

Covert recognition and the neural system for face processing

In this viewpoint, we discuss the new evidence on covert face recognition in prosopagnosia presented by Bobes et al. (2003, this issue) and by Sperber and Spinnler (2003, this issue). Contrary to earlier hypotheses, both papers agree that covert and overt face recognition are based on the same mechanism. In line with this suggestion, an analysis of reported cases with prosopagnosia indicates that a degree of successful encoding of facial representations is a prerequisite for covert recognition to occur. While we agree with this general conclusion as far as Bobes et al.'s and Sperber and Spinnler's data are concerned, we also discuss evidence for a dissociation between different measures of covert recognition. Specifically, studies in patients with Capgras delusion and patients with prosopagnosia suggest that skin conductance and behavioural indexes of covert face recognition are mediated by partially different mechanisms. We also discuss implications of the new data for models of normal face recognition that have been successful in simulating covert recognition phenomena (e.g., Young and Burton, 1999, and O'Reilly et al., 1999). Finally, in reviewing recent neurophysiological and brain imaging evidence concerning the neural system for face processing, we argue that the relationship between ERP components (specifically, N170, N250r, and N400) and different cognitive processes in face recognition is beginning to emerge.