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Data gathered in the field of the experimental social psychology have shown that it is more difficult to recognize a person through his/her voice than through his/her face and that false alarms (FA) are produced more in voice than in face recognition. Furthermore, some neuropsychological investigations have suggested that in patients with damage to the right anterior temporal lobe (ATL) the number of FA could be higher for voice than for face recognition. In the present study we assessed FA during recognition of famous people from faces and voices in patients with unilateral ATL tumours and in normal participants tested after anodal transcranial direct current stimulation (tCDS), over the left or right ATL. The number of FA was significantly higher in patients with right than in those with left temporal tumours on both face and voice familiarity. Furthermore, lesion side did not differentially affect patient's sensitivity or response criterion when recognizing famous faces, but influenced both these measures on a voice recognition task. In fact, in this condition patients with right temporal tumours showed a lower sensitivity index and a lower response criterion than those with left-sided lesions. In normal subjects, the greater right sided involvement in voice than in face processing was confirmed by the observation that right ATL anodal stimulation significantly increased voice but only marginally influenced face sensitivity. This asymmetry between face and voice processing in the right hemisphere could be due to the greater complexity of voice processing and to the difficulty of forming stable and well-structured representations, allowing to evaluate if a presented voice matches or not with an already known voice.

Acquired prosopagnosia is usually a consequence of bilateral or right hemisphere lesions and is often associated with topographical disorientation and dyschromatopsia. Left temporo-occipital lesions sometimes result in a face recognition disorder but in a context of visual object agnosia with spared familiarity feelings for faces, usually in left-handers. We describe a patient with a left temporo-occipital hemorrhagic lesion unexpectedly resulting in a deficit of face familiarity, which could represent a mild form of associative prosopagnosia. Our patient failed to feel familiarity feelings even with very well-known famous faces but had neither visual object agnosia nor defects with semantics or naming of celebrities. This was confirmed even when the patient was re-tested a year later. We speculate that a graded lateralization of face processing could be at the basis of occasional cases of prosopagnosia.

Disagreement exists regarding representational and connectionist interpretations of semantic knowledge subserved by the right versus left anterior temporal lobes (ATLs). These interpretations predict a different pattern of impairment in patients with a right unilateral ATL lesion. We conducted a neuropsychological study of a selective semantic pictorial defect exhibited by a 57-year-old man who had undergone a right temporal lobectomy due to the presence of a glioblastoma. The patient was given the Thematic and Taxonomic Semantic task, in which individuals must select, within triplets of words or pictures, the best associates of living or nonliving stimuli, related by thematic or taxonomic links, and presented in the verbal or pictorial modality. The selectivity of the defect was documented by a comparison between the results obtained by our patient and those obtained by healthy controls on living items and on pictures with a thematic relation. The selectivity of the defect was confirmed by a within-subject analysis of the results obtained on all of the task's triplets and those obtained on the stimuli representing living entities with a taxonomic relation. The selectivity of this semantic pictorial defect mainly concerning living entities is consistent with the representational account of semantic defects observed in our patient. In the present case report, a right temporal lobectomy resulted in a selective semantic pictorial defect with the qualitative features predicted by the representational account of semantic defects observed after a unilateral ATL lesion.

Disagreement exists regarding representational and connectionist interpretations of semantic knowledge subserved by the right versus left anterior temporal lobes (ATLs). These interpretations predict a different pattern of impairment in patients with a right unilateral ATL lesion. We conducted a neuropsychological study of a selective semantic pictorial defect exhibited by a 57-year-old man who had undergone a right temporal lobectomy due to the presence of a glioblastoma. The patient was given the Thematic and Taxonomic Semantic task, in which individuals must select, within triplets of words or pictures, the best associates of living or nonliving stimuli, related by thematic or taxonomic links, and presented in the verbal or pictorial modality. The selectivity of the defect was documented by a comparison between the results obtained by our patient and those obtained by healthy controls on living items and on pictures with a thematic relation. The selectivity of the defect was confirmed by a within-subject analysis of the results obtained on all of the task's triplets and those obtained on the stimuli representing living entities with a taxonomic relation. The selectivity of this semantic pictorial defect mainly concerning living entities is consistent with the representational account of semantic defects observed in our patient. In the present case report, a right temporal lobectomy resulted in a selective semantic pictorial defect with the qualitative features predicted by the representational account of semantic defects observed after a unilateral ATL lesion.

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.

We report the case of a 48 year old men who developed a selective impairment in famous voice recognition after ischemic stroke in right subcortical structures (lenticular nucleus and head of the caudate) and right anterior temporal lobe. He underwent fibrinolytic treatment. During the following days he progressively recovered and was discharged without neurological focal sign. Patent foramen ovale was found. When he got back to his house he noticed that he was unable to recognize the voice of his favoured singers and needed to ask who was the singer to his relatives. Neuropsychological examination revealed a selective impairment in famous voice recognition in the absence of alteration of voice perception, face perception and famous face recognition. All other neuropsychological domains were spared. In particular language, memory and executive functions were intact. Neuroimaging carried out by means of PET and MRI revealed two small ischemic lesions in the right subcortical region, involving lenticular and caudate nuclei and in the right temporal pole. To our knowledge, this is the first case described in literature of a patient showing a selective associative phonagnosia after right anterior temporal stroke. The present case helps to clarify the brain circuits underlying famous voice recognition and adds evidence in favour of a right hemisphere involvement in processing knowledge of familiar voices. These findings are discussed in relation to current models of brain organization of person-specific and general semantic knowledge.

In this normative study, we investigated famous people recognition through personal name, using as stimuli the names of the same 40 Italian famous persons whose faces and voices had been utilized for the normative study of the Famous People Recognition Battery. For each famous people, we assessed name familiarity, person identification (when the name had been considered as familiar), and false alarms. The investigation was carried out on 143 normal subjects who varied in age and education. Name familiarity and semantic scores were affected by educational level, whereas age influenced false alarms. A comparison between results obtained with names in this research and with faces and voices of the same famous people in our previous study showed that familiarity scores were higher for personal names than those for faces and voices, which obtained the worst scores. Person identification scores were not significantly different from names and from faces, but both these scores were significantly higher than the semantic scores obtained by voices. Taken together, these results are inconsistent with the influential interactive activation and competition model of person recognition.

Twenty-nine patients who underwent surgery for a temporal glioma, either in the left (16 patients) or right (13 patients) hemisphere, were administered standardized tests of unknown voice discrimination (UVD) and of famous voice recognition (VO-REC), which included tasks of familiarity evaluation, semantic identification and naming of famous voices. The UVD consisted of twenty stimuli, in which two audio files were consecutively presented; the subject was requested to judge whether the voices belonged to the same or different persons. In the VO-REC, patients were requested to recognize the voices of 40 very well known people; these voices were intermingled with the voices of 20 unknown people for a familiarity check, followed by identification and naming of persons recognized as familiar. We aimed at verifying the effect of laterality and intra-temporal site of lesion on familiarity assessment, false alarms, identification and naming of familiar people. As for the effect of lesion side, our results showed that patients with right temporal gliomas were significantly more impaired in voices discrimination and produced more false alarms than patients with a left glioma, who, in turn, were significantly more impaired in name retrieval than patients with a right temporal glioma. The high number of false alarms in patients with a right temporal glioma suggests that familiarity judgment was impaired. Regarding the neuroanatomical correlates of these different patterns of impairment, MRI data suggested that: (a) UVD disorders are due to lesions involving the whole right anterior temporal lobe and extending to lateral portions of the temporal and frontal lobes; (b) familiarity judgments (testified by an increased number of false alarms) are impaired in lesions restricted to the right anterior temporal lobe; (c) name retrieval deficits are found only in patients with left temporal lesions. UVD disorders were interpreted, at least in part, as due to an impairment of executive

Changes in health care and disease epidemiology have shifted the attention of neuropsychologists and cognitive neuroscientists fromvascular lesions to degenerative diseases or other bilateral brain lesions. This displacement of attention from vascular patients to patients with degenerative brain diseases allowed the discovery of hitherto unexplored and unheralded aspects of the neural substrates of human cognition. Three aspects of research on the anterior parts of the temporal lobes (ATLs) are the focus of the present review. The first aspect is category-specific semantic disorders, including current accounts of categorical brain organization, the anatomical substrate of different categories (stressing the role of the ATLs with respect to the biological categories), and the “sources of knowledge” that contribute to construction of those categories. The second aspect is the role of the ATLs in conceptual knowledge, including the “hub-and-spokes” model of semantic representation and semantic control. The third aspect is the role of the right ATL in recognition of familiar people, including the distinction made between associative prosopagnosia and multimodal disorders of person recognition. Consistencies and inconsistencies of results obtained across these different domains are discussed, and the clinical implications of these findings are considered.

Earlier studies, which suggested that anosognosia of hemiplegia might be related to right hemisphere (RH) lesions did not control for the influence of confounding variables, such as aphasia, in patients with left-hemisphere lesions and unilateral neglect in those with RH lesions. These confounding variables are absent in patients with degenerative brain disease, where a prevalence of right-sided lesions is often associated with emotional and behavioural disturbances. This review, which can be considered a ‘qualitative synthesis’ aimed, therefore, to determine whether the unawareness phenomena observed in degenerative brain diseases are linked to the RH dominance for emotions. Results of the review confirmed that the neural correlates of anosognosia are often right lateralised in patients with degenerative brain diseases and that emotional disturbances are associated with right frontal lesions and anosognosia in the behavioural variant, i.e., frontotemporal dementia (bvFTD). However, they also showed that anosognosia is a heterogeneous phenomenon and that the role of right frontal lesions is much greater when the loss of insight concerns emotion-linked aspects of personality or behaviour than when it concerns particular aspects of cognition or memory.

Objective: Familiar face recognition disorders are often observed in patients with lesions of the right anterior temporal lobe (ATL). It is not clear, however, if this defect must be considered as a form of associative prosopagnosia, or as a multimodal (face and voice) people recognition disorder, because voice recognition is rarely examined in these patients. The most appropriate manner of solving this problem could consist in evaluating, in one or more patients with right ATL lesions, recognition disorders through face and voice of the same well known people. Methods: The 'Famous People Recognition Battery' (FPRB), in which the same 40 persons (very well-known at the national level) should be identified through face and voice recognition, was used to clarify this issue. The FPRB was administered to a 56-year-old woman (BM) who complained, as early sign of a fronto-temporal degeneration, of familiar people recognition defects in a context of relatively intact cognitive functions. Results: On the FPRB, BM showed a severe defect of people recognition (familiarity judgement) and identification through face and voice, but not through personal name. Voxel-based morphometry showed a focal atrophy of the right ATL (temporo-polar cortex and anterior parts of perirhinal and entorhinal cortices). Conclusions: the present case report seems to show that a unilateral right ATL atrophy can lead to a multimodal people recognition disorder through face and voice, in the absence of recognition difficulties through personal name.

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.

Acquired prosopagnosia is usually a consequence of bilateral or right hemisphere lesions and is often associated with topographical disorientation and dyschromatopsia. Left temporo-occipital lesions sometimes result in a face recognition disorder but in a context of visual object agnosia with spared familiarity feelings for faces, usually in left-handers. We describe a patient with a left temporo-occipital hemorrhagic lesion unexpectedly resulting in a deficit of face familiarity, which could represent a mild form of associative prosopagnosia. Our patient failed to feel familiarity feelings even with very well-known famous faces but had neither visual object agnosia nor defects with semantics or naming of celebrities. This was confirmed even when the patient was re-tested a year later. We speculate that a graded lateralization of face processing could be at the basis of occasional cases of prosopagnosia.

According to the original “hub-and-spoke” model of conceptual representations, the neural network for semantic memory requires a single convergence zone located in the anterior temporal lobes (ATLs). However, a more recent version of this model acknowledges that a graded specialization of the left and right ATLs might emerge as a consequence of their differential connectivity with language and sensory-motor regions. A recent influential paper maintained that both the format of semantic representations (representational account) and their differential connectivity (connectivity account) could contribute to the cognitive consequences of atrophy to the left versus the right ATL atrophy. That paper, however, also raised questions as to whether the distinction between representational and connectivity accounts is a meaningful question. I argue that an important theoretical difference exists between the representational and the connectivity-based models and that investigations, based on this difference, should allow to choose between these alternative accounts.

Controversies exist over the format of person-specific semantic representations in healthy subjects and the loss of part of these representations in conditions of brain pathology. Some authors have suggested that in brain-damaged patients item-specific consistency of errors through different recognition modalities might indicate a loss of person-specific information. This view is hindered by the fact that item consistency might also be variable in healthy subjects, because names, faces and voices have different degrees of effectiveness in the recognition of familiar people. The aim of the present research was to try to clarify this issue by assessing the value of consistency of semantic retrieval in a large sample of Italian healthy subjects who had judged as familiar the faces and voices of 40 Italian celebrities. The effect of fame level on item consistency was also evaluated. Results showed that the degree of item consistency between faces and voices was rather variable, for example it was influenced by fame level when the latter was based on an integrated (non-verbal) face/voice familiarity score, but not when it was based on the celebrities’ names in a (verbal) questionnaire. The consistency between non-verbal assessment of fame and item consistency in retrieving information from faces and voices suggests a different specialization of the left anterior temporal lobe (ATL) for the verbally coded aspects of personal semantics and of the right ATL for the visual (face) and auditory (voice) aspects of person representation.

This paper reviews some controversies concerning the original and revised versions of the 'hub-and-spoke' model of conceptual representations and their implication for abstraction capacity levels. The 'hub-and-spoke' model, which is based on data gathered in patients with semantic dementia (SD), is the most authoritative model of conceptual knowledge. Patterson et al.'s (Nature Reviews Neuroscience, 8(12), 976-987, 2007) classical version of this model maintained that conceptual representations are stored in a unitary 'amodal' format in the right and left anterior temporal lobes (ATLs), because in SD the semantic disorder cuts across modalities and categories. Several authors questioned the unitary nature of these representations. They showed that the semantic impairment is 'multi-modal'only in the advanced stages of SD, when atrophy affects the ATLs bilaterally, but that impariments can be modality-specific in lateralised (early) stages of the disease. In these cases, SD mainly affects lexical-semantic knowledge when atrophy predominates on the left side and pictorial representations when atrophy prevails on the right side. Some aspects of the model (i.e. the importance of spokes, the multimodal format of representations and the graded convergence of modalities within the ATLs), which had already been outlined by Rogers et al. (Psychological Review, 111(1), 205-235, 2004) in a computational model of SD, were strengthened by these results. The relevance of these theoretical problems and of empirical data concerning the neural substrate of concrete and abstract words is discussed critically. The conclusion of the review is that the highest levels of abstraction are due more to the structuring influence of language than to the format of representations.

Introduction Numerous diagnostic criteria have tried to tackle the variability in clinical manifestations and problematic diagnosis of vascular cognitive impairment (VCI) but none have been universally accepted. These criteria have not been readily comparable, impacting on clinical diagnosis rates and in turn prevalence estimates, research, and treatment. Methods The Vascular Impairment of Cognition Classification Consensus Study (VICCCS) involved participants (81% academic researchers) from 27 countries in an online Delphi consensus study. Participants reviewed previously proposed concepts to develop new guidelines. Results VICCCS had a mean of 122 (98–153) respondents across the study and a 67% threshold to represent consensus. VICCCS redefined VCI including classification of mild and major forms of VCI and subtypes. It proposes new standardized VCI-associated terminology and future research priorities to address gaps in current knowledge. Discussion VICCCS proposes a consensus-based updated conceptualization of VCI intended to facilitate standardization in research.

Background: Two main models have been advanced to explain the asymmetries observed in the representation and processing of emotions. The first model, labeled “the right hemisphere hypothesis,” assumes a general dominance of the right hemisphere for all emotions, regardless of affective valence. The second model, named “the valence hypothesis,” assumes an opposite dominance of the left hemisphere for positive emotions and the right hemisphere for negative emotions. Patients with frontotemporal lobar degeneration (FTLD) could contribute to clarifying this issue, because disorders of emotional and social behavior are very common in FTLD and because atrophy, which affects the antero-ventral part of the frontal and temporal lobes, can be clearly asymmetric in the early stages of this disease. Objective: The main scope of the present review therefore consists of evaluating if results of investigations conducted on emotional and behavioral disorders of patients with right and left FTLD, support the “right hemisphere” or the “valence” hypothesis. Method: A thorough review of behavioral and emotional disorders in FTLD patients, found that 177 possible studies, but only 32 papers met the requested criteria for inclusion in our review. Results: Almost all (25 out of 26) studies were relevant with respect to the “right hemisphere hypothesis” and supported the assumption of a general dominance of the right hemisphere for emotional functions, whereas only one of the six investigations were relevant with respect to the “valence hypothesis” and were in part consistent with this hypothesis, though these are also open to interpretation in terms of the “right hemisphere” hypothesis. Conclusions: This study, therefore, clearly supports the model of a general dominance of the right hemisphere for all emotions, regardless of affective valence.

Models advanced to explain hemispheric asymmetries in representation of emotions will be discussed following their historical progression. First, the clinical observations that have suggested a general dominance of the right hemisphere for all kinds of emotions will be reviewed. Then the experimental investigations that have led to proposal of a different hemispheric specialization for positive versus negative emotions (valence hypothesis) or, alternatively, for approach versus avoidance tendencies (motivational hypothesis) will be surveyed. The discussion of these general models will be followed by a review of recent studies which have documented laterality effects within specific brain structures, known to play a critical role in different components of emotions, namely the amygdata in the computation of emotionally laden stimuli, the ventromedial prefrontal cortex in the integration between cognition and emotion and in the control of impulsive reactions and the anterior insula in the conscious experience of emotion. Results of these recent investigations support and provide an updated integrated version of early models assuming a general right hemisphere dominance for all kinds of emotions.

Different models of emotional lateralization, advanced since the first clinical observations raised this issue, will be reviewed following their historical progression. The clinical investigations that have suggested a general dominance of the right hemisphere for all kinds of emotions and the experimental studies that have proposed a different hemispheric specialization for positive vs. negative emotions (valence hypothesis) or for approach vs. withdrawal tendencies (motivational hypothesis) will be reviewed first and extensively. This historical review will be followed by a short discussion of recent anatomo-clinical and activation studies that have investigated (a) emotional and behavioral disorders of patients with asymmetrical forms of fronto-temporal degeneration and (b) laterality effects in specific brain structures (amygdala, ventro-medial prefrontal cortex, and anterior insula) playing a critical role in different components of emotions. Overall, these studies support the hypothesis of a right hemisphere dominance for all components of the emotional system.

The target article carefully describes the memory system, centered on the temporal lobe that builds specific memory traces. It does not, however, mention the laterality effects that exist within this system. This commentary briefly surveys evidence showing that clear asymmetries exist within the temporal lobe structures subserving the core system and that the right temporal structures mainly underpin face familiarity feelings.

Introduction: Both the neuropsychological study of patients with category-specific semantic disorders (CSSD) and the experimental research on categorical processing in healthy subjects (HSs) have shown that men are mainly impaired with fruits and vegetables and women with animals and artifacts. Since this difference is more striking in patients with CSSD than in HSs, we hypothesized that the lack of power of some investigations conducted with HSs and the different methods used in studies conducted with HSs and patients with CSSD could explain some of these inconsistencies and that a study conducted with a very large number of HSs using visual naming tasks should strongly confirm the role of gender in categorical tasks. Methods: Picture naming data gathered during the last ten years with our category-specificity paradigm from a large number (702) of HSs were reanalyzed. Results: As predicted, men named significantly more animals and artifacts, while women named more plant life items. Discussion: These data confirm that, if different domains of knowledge are studied in a very large sample of HSs using a picture naming task equivalent to the naming tasks used in most anatomo-clinical studies on CSSD, then the gender effects are highly significant.

Even if Babinski (1914) is usually considered as the discoverer of anosognosia, other authors before him contributed to the development of this construct. Von Monakow (1885) and Dejerine and Vialet (1893) gave the first descriptions of patients with cortical blindness who were unaware of their disability, but did not distinguish this unawareness from the rest of the clinical description. Anton (1999) described patients with cortical deafness and cortical blindness, considering these defects of awareness as a symptom independent from the neurological dysfunction. He conceptualized them as a phenomenon in its own right and tried to link this unawareness of a disability with specific neuro-anatomical changes. Finally, Babinski (1914) coined the term "anosognosia" to designate the clinical entity conceptualized by Anton (1899) and extended this concept from the unawareness of cortical deafness and blindness to the unawareness of hemiplegia. The choice of the term "anosognosia" to denote the observed phenomenon was important, because referring to "lack of knowledge of the disease" (anosognosia), he not only emphasized the separation between "lack of knowledge" and "disease, " but also suggested a general use of this term, because disease can refer to many other disabilities besides hemiplegia. Further investigations have shown that: (a) brain-damaged patients may be unaware of different kinds of disabilities; (b) anosognosia can be selective, in that an affected person with multiple impairments may be unaware of only one handicap, while appearing fully aware of any others; and (c) lack of acknowledgment of a disease may not necessarily be due to a defective awareness, but must sometimes be considered as an extreme but understable pattern of adaptation to stress. For this condition, the term "Denial of Illness" seems preferable to that of anosognosia. Anosognosia must perhaps be viewed as a multifaceted phenomenon, resulting from both cognitive and motivational factors.