Time-dependent neural activations related to recognition of people's names in emotional and neutral face-name associative learning:

Integrating mind and body: Investigating differential activation of nodes of the default mode network

BACKGROUND

The default mode network (DMN) is a large-scale brain network tightly correlated with self and self-referential processing, activated by intrinsic tasks and deactivated by externally-directed tasks.

OBJECTIVE

In this study, we aim to investigate the novel approach of default mode activation during progressive muscle relaxation and examine whether differential activation patterns result from the movement of different body parts.

METHODS

We employed neuroimaging to investigate DMN activity during simple body movements, while performing progressive muscle relaxation. We focused on differentiating the neural response between facial movements and movements of other body parts.

RESULTS

Our results show that the movement of different body parts led to deactivation in several DMN nodes, namely the temporal poles, hippocampus, medial prefrontal cortex (mPFC), and posterior cingulate cortex. However, facial movement induced an inverted and selective positive BOLD pattern in some of these areas precisely. Moreover, areas in the temporal poles selective for face movement showed functional connectivity not only with the hippocampus and mPFC but also with the nucleus accumbens.

CONCLUSIONS

Our findings suggest that both conceptual and embodied self-related processes, including body movements during progressive muscle relaxation, may be mapped onto shared brain networks. This could enhance our understanding of how practices like PMR influence DMN activity and potentially offer insights to inform therapeutic strategies that rely on mindful body movements.

Examining the role of the uncinate fasciculus in proper noun naming: awake brain tumor resections and stereo EEG targeted electrical stimulation multiple case study

While there is strong evidence from lesion and functional imaging studies implicating the left anterior temporal pole (LTP) in naming unique entities, less is known about white matter tracts in category-specific naming. We present evidence that implicates the uncinate fasciculus (UF) in proper noun naming. First, we describe two patients with left LTP gliomas who developed category specific worsening in proper noun naming in real time during awake surgery when the UF was surgically involved . We then describe a third case involving targeted electrical stimulation of the UF using stereo-electroencephalography (sEEG) that resulted in category specific naming disturbance for proper nouns..

Modulation of proper name recall by transcranial direct current stimulation of the anterior temporal lobes

We often fail to recall another person's name. Proper names might be more difficult to memorize and retrieve than other pieces of knowledge, such as one's profession because they are processed differently in the brain. Neuroimaging and neuropsychological studies associate the bilateral anterior temporal lobes (ATL) in the retrieval of proper names and other person-related knowledge. Specifically, recalling a person's name is thought to be supported by the left ATL, whereas recalling specific information such as a person's occupation is suggested to be subserved by the right ATL. To clarify and further explore the causal relationship between both ATLs and proper name retrieval, we stimulated these regions with anodal, cathodal and sham transcranial direct current stimulation (tDCS) while the participants memorized surnames (e.g., Mr. Baker) and professions (e.g., baker) presented with a person’s face. The participants were then later asked to recall the surname and the profession. Left ATL anodal stimulation resulted in higher intrusion errors for surnames than sham, whereas right ATL anodal stimulation resulted in higher overall intrusion errors, both, surnames and professions, compared to cathodal stimulation. Cathodal stimulation of the left and right ATL had no significant effect on surname and profession recall. The results indicate that the left ATL plays a role in recalling proper names. On the other hand, the specific role of the right ATL remaines to be explored.

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.

Predicting pediatric anxiety from the temporal pole using neural responses to emotional faces

A prominent cognitive aspect of anxiety is dysregulation of emotional interpretation of facial expressions, associated with neural activity from the amygdala and prefrontal cortex. We report machine learning analysis of fMRI results supporting a key role for a third area, the temporal pole (TP) for childhood anxiety in this context. This finding is based on differential fMRI responses to emotional faces (angry versus fearful faces) in children with one or more of generalized anxiety, separation anxiety, and social phobia (n = 22) compared with matched controls (n = 23). In our machine learning (Adaptive Boosting) model, the right TP distinguished anxious from control children (accuracy = 81%). Involvement of the TP as significant for neurocognitive aspects of pediatric anxiety is a novel finding worthy of further investigation.

Facial expression recognition: A meta-analytic review of theoretical models and neuroimaging evidence

Discrimination of facial expressions is an elementary function of the human brain. While the way emotions are represented in the brain has long been debated, common and specific neural representations in recognition of facial expressions are also complicated. To examine brain organizations and asymmetry on discrete and dimensional facial emotions, we conducted an activation likelihood estimation meta-analysis and meta-analytic connectivity modelling on 141 studies with a total of 3138 participants. We found consistent engagement of the amygdala and a common set of brain networks across discrete and dimensional emotions. The left-hemisphere dominance of the amygdala and AI across categories of facial expression, but category-specific lateralization of the vmPFC, suggesting a flexibly asymmetrical neural representations of facial expression recognition. These results converge to characteristic activation and connectivity patterns across discrete and dimensional emotion categories in recognition of facial expressions. Our findings provide the first quantitatively meta-analytic brain network-based evidence supportive of the psychological constructionist hypothesis in facial expression recognition.

Proper names from story recall are associated with beta-amyloid in cognitively unimpaired adults at risk for Alzheimer's disease

Due to advances in the early detection of Alzheimer's disease (AD) biomarkers including beta-amyloid (Aβ), neuropsychological measures that are sensitive to concurrent, subtle changes in cognition are critically needed. Story recall tasks have shown sensitivity to early memory declines in persons with mild cognitive impairment (MCI) and early stage dementia, as well as in persons with autosomal dominantly inherited AD up to 10 years prior to a dementia diagnosis. However, the evidence is inconclusive regarding relationships between evidence of Aβ and story recall measures. Because story recall tasks require the encoding and delayed retrieval of several lexical-semantic categories, such as proper names, verbs, and numerical expressions, and because lexical categories have been shown to be differentially impaired in persons with MCI, we focused on item-level analyses of lexical-semantic retrieval from a quintessential story recall task, Logical Memory from the Wechsler Memory Scale-Revised. Our objective was to investigate whether delayed recall of lexical categories (proper names, verbs and/or numerical expressions), as well as the traditional total score measure, was associated with "preclinical AD," or cognitively unimpaired adults with positive Aβ deposition on positron emission tomography (PET) neuroimaging using Pittsburgh Compound B (PiB). We developed an item-level scoring system, in which we parsed items into lexical categories and examined the immediate and delayed recall of these lexical categories from 217 cognitively unimpaired participants from the Wisconsin Registry for Alzheimer's Prevention (WRAP). We performed binary logistic regression models with story recall score as predictor and Aβ status (positive/negative) as the outcome. Using baseline Logical Memory data, proper names from delayed story recall were significantly associated with Aβ status, such that participants who recalled more proper names were less likely to be classified as PiB(+) (odds ratio = .58, p = .01). None of the other story recall variables, including total score, were associated with PiB status. Secondary analyses determined that immediate recall of proper names was not significantly associated with Aβ, suggesting a retrieval deficit rather than that of encoding. The present findings suggest that lexical semantic retrieval measures from existing story recall tasks may be sensitive to Aβ deposition, and may provide added utility to a widely-used, long-standing neuropsychological test for early detection of cognitive decline on the AD continuum.

The cognitive psychology and neuroscience of naming people

The use of proper names enables us to designate entities, including people, at a very specific level of categorization: the unique entity or the individual. The paper presents a general overview of psychological/cognitive and neuroscientific studies that have compared the production of proper names, in particular people's names, with the production of common nouns during the last thirty years. The search for specific brain correlates of proper naming included single-case and group studies of patients with brain lesions, and studies utilizing functional neuroimaging or brain electrical stimulation with healthy participants. These studies have led neuroscientists to hypothesize that the recall of proper names involves a rather complex network including mainly left frontal and temporal regions. Behavioural evidence supports the view that proper names are more difficult to recall than common names, and scientists have proposed different explanations for this relative difficulty. Finally, several new directions for future research are proposed to improve our understanding of both cognitive processes and their brain correlates involved during proper name recall.

Characterizing cerebellar activity during autobiographical memory retrieval: ALE and functional connectivity investigations

Previous neuroimaging research has shown that the cerebellum is often activated during autobiographical memory (AM) retrieval. However, the reliability of that activation, its localization within the cerebellum, and its relationship to other areas of the AM network remains unknown. The current study used Activation Likelihood Estimation meta-analysis (ALE) as well as resting-state and task-related functional connectivity analyses to better characterize cerebellar activation in relation to AM. The ALE meta-analysis was run on 32 neuroimaging studies of AM retrieval. The results revealed a cluster of reliable AM-related activity within the Crus I lobule of the right posterior cerebellum. Using the peak ALE coordinate within Crus I as a seed region, both task-related and resting state functional connectivity analyses were run on fMRI data from 38 healthy participants. To determine the specificity of connectivity patterns to Crus I, we also included a cerebellar seed region in right Lobule VI previously identified in an ALE meta-analysis as associated with working memory. Resting-state functional connectivity analyses indicated that Crus I was intrinsically connected with other areas of the AM network as well as surrounding and contralateral cerebellar regions. In contrast, the Lobule VI seed was functionally connected with cerebral and cerebellar regions typically associated with working memory. The task-related connectivity analyses revealed a similar pattern, where the Crus I seed exhibited significant connectivity with key nodes of the AM network while the Lobule IV seed did not. During a semantic control task, both Crus I and Lobule VI showed significant correlations with a network of regions that was largely distinct from the AM network. Together these results indicate that right Crus I lobule is reliably engaged during AM retrieval and is functionally connected to the AM network both during rest, and more importantly, during AM retrieval.

Anterior temporal face patches: a meta-analysis and empirical study

Evidence suggests the anterior temporal lobe (ATL) plays an important role in person identification and memory. In humans, neuroimaging studies of person memory report consistent activations in the ATL to famous and personally familiar faces and studies of patients report resection or damage of the ATL causes an associative prosopagnosia in which face perception is intact but face memory is compromised. In addition, high-resolution fMRI studies of non-human primates and electrophysiological studies of humans also suggest regions of the ventral ATL are sensitive to novel faces. The current study extends previous findings by investigating whether similar subregions in the dorsal, ventral, lateral, or polar aspects of the ATL are sensitive to personally familiar, famous, and novel faces. We present the results of two studies of person memory: a meta-analysis of existing fMRI studies and an empirical fMRI study using optimized imaging parameters. Both studies showed left-lateralized ATL activations to familiar individuals while novel faces activated the right ATL. Activations to famous faces were quite ventral, similar to what has been reported in previous high-resolution fMRI studies of non-human primates. These findings suggest that face memory-sensitive patches in the human ATL are in the ventral/polar ATL.

The function of the anterior temporal lobe: a review of the empirical evidence

Recent work on the anterior temporal lobe (ATL) has lead to substantively different theoretical branches, of its putative functions, that have in some part developed independently of one another. The ATL has dense connectivity with a number of sensory modalities. This has resulted in empirical evidence that supports different functionality dependent upon the variables under investigation. The main bodies of evidence have implicated the ATL as a domain-general semantic hub, whilst other evidence points to a domain-specific role in social or 'person-related' processing. A third body of evidence suggests that the ATLs underlie processing of unique entities. Primarily, research of the ATL has been based on lesion studies and from clinical populations such as semantic dementia or temporal lobe epilepsy patients. Although important, this neuropsychological evidence has a number of confounds, therefore techniques such as functional neuroimaging on healthy participants and the relatively novel use of non-invasive brain stimulation may be more useful to isolate specific variables that can discriminate between these different theories concerning 'normal' function. This review focuses on these latter types of studies and considers the empirical evidence for each perspective. The overall literature is integrated in an attempt to formulate a unifying theory and the functional sub-regions within the ATL are explored. It is concluded that a holistic integration of the theories is feasible in that the ATLs could process domain-general semantic knowledge but with a bias towards social information or stimuli that is personally relevant. Thus, it may be the importance of social/emotional information that gives it priority of processing in the ATL not an inherent property of the structure itself.

Brain gray matter deficits at 33-year follow-up in adults with attention-deficit/hyperactivity disorder established in childhood

CONTEXT

Volumetric studies have reported relatively decreased cortical thickness and gray matter volumes in adults with attention-deficit/hyperactivity disorder (ADHD) whose childhood status was retrospectively recalled. We present, to our knowledge, the first prospective study combining cortical thickness and voxel-based morphometry in adults diagnosed as having ADHD in childhood.

OBJECTIVES

To test whether adults with combined-type childhood ADHD exhibit cortical thinning and decreased gray matter in regions hypothesized to be related to ADHD and to test whether anatomic differences are associated with a current ADHD diagnosis, including persistent vs remitting ADHD.

DESIGN

Cross-sectional analysis embedded in a 33-year prospective follow-up at a mean age of 41.2 years.

SETTING

Research outpatient center.

PARTICIPANTS

We recruited probands with ADHD from a cohort of 207 white boys aged 6 to 12 years. Male comparison participants (n = 178) were free of ADHD in childhood. We obtained magnetic resonance images in 59 probands and 80 comparison participants (28.5% and 44.9% of the original samples, respectively).

MAIN OUTCOME MEASURES

Whole-brain voxel-based morphometry and vertexwise cortical thickness analyses.

RESULTS

The cortex was significantly thinner in ADHD probands than in comparison participants in the dorsal attentional network and limbic areas (false discovery rate < 0.05, corrected). In addition, gray matter was significantly decreased in probands in the right caudate, right thalamus, and bilateral cerebellar hemispheres. Probands with persistent ADHD (n = 17) did not differ significantly from those with remitting ADHD (n = 26) (false discovery rate < 0.05). At uncorrected P < .05, individuals with remitting ADHD had thicker cortex relative to those with persistent ADHD in the medial occipital cortex, insula, parahippocampus, and prefrontal regions.

CONCLUSIONS

Anatomic gray matter reductions are observable in adults with childhood ADHD, regardless of the current diagnosis. The most affected regions underpin top-down control of attention and regulation of emotion and motivation. Exploratory analyses suggest that diagnostic remission may result from compensatory maturation of prefrontal, cerebellar, and thalamic circuitry.

Anomia for people's names after left anterior temporal lobe resection--case report

A 47-year-old man was admitted to our hospital with an intrinsic brain tumor in the left anterior temporal lobe. Preoperative sodium thiopental test demonstrated left hemispheric dominance. Awake craniotomy was performed for dominant-hemispheric tumor resection using language mapping to identify the stimulation-induced positive language area. The tasks of object naming and repetition were used, along with specific tests for famous people's names. The language area was detected on the superior temporal gyrus and preserved. Following surgery, this patient was unable to retrieve the names of famous individuals (i.e. anomia for people's name) despite preservation of semantic knowledge for those individuals. This anomia for people's names showed no improvement at all for a period of 15 months. This case report and other sporadic cases with this type of deficit reveal the left anterior temporal lobe is an important brain area for retrieving people's names.

Temporal pole activity during understanding other persons' mental states correlates with neuroticism trait

Comprehension of other persons' mental states is one of the representative cognitive functions involved in social situations. It has been suggested that this function sometimes recruits emotional processes. The present fMRI study examined the neural mechanisms associated with understanding others' mental states, and the conditions that determine the recruitment of the emotional processes. The false belief paradigm, a traditional behavioral paradigm to investigate comprehension of others, was applied to an event-related fMRI analysis, allowing for the extraction of brain activity time-locked to successful understanding of others' mental states. Prominent brain activity was observed in multiple cortical regions including the medial prefrontal cortex, temporo-parietal junction, precuneus, and temporal pole. Then, correlational analyses were performed between the activations and individuals' scores of neuroticism, a personality trait that reflects emotional instability in daily life. It was revealed that the neuroticism scores were positively correlated with the activity in the temporal pole region, but not in the other regions. These results suggest that the emotional processes implemented in the temporal pole are recruited during successful understanding of other persons' mental states, and that the recruitment may be modulated by an emotional personality trait of individual subjects.

Social cognition and the anterior temporal lobes

Two distinct literatures have emerged on the functionality of the anterior temporal lobes (ATL): in one field, the ATLs are conceived of as a repository for semantic or conceptual knowledge. In another field, the ATLs are thought to play some undetermined role in social-emotional functions such as Theory of Mind. Here we attempted to reconcile these distinct functions by assessing whether social semantic processing can explain ATL activation in other social cognitive tasks. Social semantic functions refer to knowledge about social concepts and rules. In a first experiment we tested the idea that social semantic representations can account for activations in the ATL to social attribution stimuli such as Heider and Simmel animations. Left ATL activations to Heider and Simmel stimuli overlapped with activations to social words. In a second experiment we assessed the putative roles of the ATLs in the processing of narratives and theory of mind content and found evidence for a role of the ATLs in the processing of theory of mind but not narrative per se. These findings indicate that the ATLs are part of a neuronal network supporting social cognition and that they are engaged when tasks demand access to social conceptual knowledge.

The anterior temporal lobes and the functional architecture of semantic memory

Recently, three accounts have emerged on the role of the anterior temporal lobes (ATLs) in semantic memory. One account claims that the ATLs are domain-general semantic hubs, another claims that they underlie knowledge of unique entities specifically, and yet another account claims that they support social conceptual knowledge generally. Here, we review neuropsychological and neuroimaging studies that bear on these three accounts and offer suggestions for future research to elucidate the roles of the ATLs in semantic memory.

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.

Differential contributions of the anterior temporal and medial temporal lobe to the retrieval of memory for person identity information

Although previous studies have suggested the importance of the bilateral anterior temporal (ATL) and medial temporal lobes (MTL) in the retrieval of person identity information, there is little evidence concerning how these regions differentially contribute to the process. Here we investigated this question using functional magnetic resonance imaging (fMRI). Before scanning, subjects learned associations among faces (F), names (N), and job titles (as a form of person-related semantics, S). During retrieval with fMRI, subjects were presented with previously learned and new S stimuli, and judged whether the stimuli were old or new. Successful retrieval (H) trials were divided into three conditions: retrieval of S and associated F and N (HSFN); retrieval of S and associated F (HSF); and retrieval of S only (HS). The left ATL was significantly activated in HSFN, compared to HSF or HS, whereas the right ATL and MTL were significantly activated in HSFN and HSF relative to HS. In addition, activity in bilateral ATL was significantly correlated with reaction time for HSFN, whereas we found no significant correlation between activity in the right MTL and reaction time in any condition. The present findings suggest that the left ATL may mediate associations between names and person-related semantic information, whereas the right ATL mediates the association between faces and person-related semantic information in memory for person identity information. In addition, activation of the right MTL region implies that this area may contribute to a more general relational processing of associative components, including memory for person identity information.

Temporal pole activity during perception of sad faces, but not happy faces, correlates with neuroticism trait

It is known that the temporal cortex is involved in perception of emotional facial expressions, and the involvement is relatively independent of the emotional valence of those expressions. The present study revealed a valence-dependent aspect of the temporal cortex through individual differences analyses involving the neuroticism trait, one of the representative affective personality traits. Functional MRI was administered while subjects classified expressions of faces, and neuroticism scores were obtained from individual subjects. Significant brain activity was observed in the temporal pole (TP) during perception of both happy and sad expressions relative to neutral expressions. Correlational analyses revealed that TP activity during perception of sad expressions, but not happy expressions, correlated with the neuroticism scores. These results demonstrate differential roles for the temporal cortex in perception of happy and sad faces, and suggest that TP recruitment during understanding of negative emotions is dependent on the personality of the individuals.

The anatomic correlate of prosopagnosia in semantic dementia

OBJECTIVE

To determine the anatomic correlate of prosopagnosia in subjects with semantic dementia.

METHODS

We identified all subjects who had been evaluated by an experienced behavioral neurologist, met criteria for semantic dementia, and had completed a volumetric head MRI scan. In all subjects, historical records were reviewed and subjects in which the presence (n = 15) or absence (n = 12) of prosopagnosia was specifically ascertained by the neurologist were identified. Voxel-based morphometry was used to assess patterns of gray matter atrophy in subjects with and without prosopagnosia compared to a group of age and gender-matched normal controls, and compared to each other.

RESULTS

Compared to controls, both groups showed prominent temporal lobe volume loss. Those with prosopagnosia showed bilateral loss but with greater involvement of the right temporal lobe, while those without prosopagnosia showed predominantly left anterior temporal lobe loss. On direct comparison, subjects with prosopagnosia showed greater loss predominantly in the right amygdala, hippocampus, fusiform gyrus, and anterior temporal pole than those without prosopagnosia. No regions were involved to a greater degree in those without prosopagnosia, compared to those with prosopagnosia.

CONCLUSIONS

Prosopagnosia appears to be associated with volume loss of the right temporal lobe, particularly medial temporal lobe, fusiform gyrus, and anterior temporal pole, although in semantic dementia it is occurring in the context of bilateral temporal lobe volume loss.

Role of left superior temporal gyrus during name recall process: an event-related fMRI study

When we cannot recall the name of a well-known person despite preserved access to his/her semantic knowledge, a phonological hint such as his/her initials sometimes helps us to recall the name. This type of recall failure appeared to occur by the transmission deficit from the lexical-semantic stage to the lexical-phonological stage in name recall processes, and the phonological cue appeared to activate this transmission, which leads to successful recall. We hypothesized that the brain regions responsible for the transmission would respond to the phonological cue that facilitates name recall, and would also respond to successful recall. A famous face image was presented with a phonological cue, and the subjects were required to recall and overtly pronounce the name during fMRI scanning. The behavioral results showed that the first syllable cue induced greater number of successful recall trials than both the non-verbal sound of the chime and the non-first syllable cue, suggesting that the first syllable facilitated name recall. The fMRI results demonstrated that two regions in the left superior temporal gyrus responded more strongly to the first syllable than both to the non-verbal sound of the chime and to the non-first syllable. In addition, these two regions were activated when the name recall was successful. These results suggest that two regions in the left superior temporal gyrus may play a crucial role in the transmission from the lexical-semantic to the lexical-phonological stage in the name recall processes.

Face familiarity feelings, the right temporal lobe and the possible underlying neural mechanisms

A comprehensive review was made of the relationships between right hemisphere and face familiarity feelings, taking separately into account: (a) studies of patients with unilateral lesions of the anterior or the posterior parts of the right and left temporal lobes, who showed a familiar people recognition disorder, (b) studies of right and left brain-damaged patients, presenting an increased familiarity for unknown persons or abnormal familiarity feelings for well known people, (c) results of studies conducted in normal subjects to evaluate the lateralization of face familiarity feelings. In this last section, we separately reviewed: results obtained by means of separate presentation of familiar and unfamiliar faces to the right and left visual fields; lateralization of event-related potentials evoked by familiar vs unfamiliar faces; results of activation studies presenting familiar and unfamiliar faces. Taken together, results of this review have shown that face familiarity feelings are specifically generated by the right hemisphere. Clinical and neurophysiological data suggest that familiarity feelings: (1) are probably due to a lateralized subcortical route, allowing a first, unconscious, global recognition of familiar faces and (2) facilitate the subsequent distinction of known faces (unconsciously detected) from unfamiliar faces. Results of the review have also shown that the right frontal areas play an important role in the production or monitoring of inappropriate familiarity decisions.

Preserved proper naming following left anterior temporal lobectomy is associated with early age of seizure onset

PURPOSE

Anterior temporal lobectomy (ATL) is an effective surgical option for managing pharmacoresistant temporal lobe epilepsy. Many patients with left ATL develop postsurgical difficulties with proper name retrieval, although curiously, some patients have entirely intact proper naming following left ATL. Here, we tested the hypothesis that early age of seizure onset would be a reliable factor "protecting" patients from developing proper naming defects following left ATL.

METHODS

Proper naming of unique persons (Famous Faces Test, 155 items) and places (Landmark Test, 65 items) was measured in 23 patients who had undergone left ATL for pharmacoresistant epilepsy. Data were collected for a number of variables, including age of seizure onset, age at surgery, handedness, IQ, and seizure outcome. The patients were sorted into two groups based on proper naming performance: (1) Unimpaired: 7 patients performed normally on both the Faces and Landmark tests; (2) Impaired: 16 patients performed abnormally on one or both of the tests.

RESULTS

In support of our hypothesis, the Unimpaired group had a significantly earlier age of seizure onset (M = 2.1 years) than the Impaired group (M = 15.1 years). Moreover, a correlation analysis indicated a strong association between age of seizure onset and naming outcome (R =-0.569). The groups were comparable (and statistically indistinguishable) on nearly all other variables.

CONCLUSIONS

These findings document the importance of age of seizure onset in predicting proper naming outcome following left ATL (with earlier being better), and extend understanding of brain reorganization and plasticity.

Memory-related ERP components for experimentally learned faces and names: characteristics and parallel-test reliabilities

Previous research with preexperimentally familiar faces and names has identified several memory-related components in the event-related potential (ERP). Here we aimed to characterize these components while controlling the quality of long-term memory with a standardized learning procedure for unfamiliar faces and names. After 1 week, recognition was tested in a repetition priming paradigm. Both early repetition effects (ERE/N250r) and old/new effects had very similar time course and domain-related scalp topographies as has been reported for preexperimentally familiar stimuli. The late repetition effects (LRE/N400) showed domain-specific scalp topographies, possibly reflecting the greater ease of deriving semantic codes from faces. Importantly, parallel-test reliabilities of performance and memory-related ERP components were high, thus demonstrating the utility of face learning for formal assessment procedures in person recognition.

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).

Dissociable roles of the bilateral anterior temporal lobe in face-name associations: an event-related fMRI study

Previous studies have suggested the importance of bilateral anterior temporal regions in face-name associations, but there is little evidence concerning their precise role. In this fMRI study, we investigated the effects of person-related semantics (PS) and repeated learning (R) on activations in these regions during the retrieval of face-name associations. For encoding stimuli, we prepared four lists of faces. To control the factor of PS, people's and occupation names were attached to the faces in lists A and B, whereas only people's names were attached to the faces in lists C and D. To control the factor of R, the stimuli in lists A and C were learned twice, whereas the stimuli in lists B and D were learned seven times during encoding before fMRI. During fMRI after the encoding, subjects participated in the retrieval task of people's names from faces or in the retrieval task of faces from people's names. The left anterior temporal lobe was significantly activated during the retrieval of people's names from faces encoded with, compared to without, PS; whereas the right anterior temporal lobe was activated during the retrieval of people's faces from names, compared to without, this encoding. Also, activation of the left (but not the right) anterior temporal lobe was significantly reduced after R of face-name associations. These findings suggest that the three components of faces, names, and PS may be mutually mediated by the bilateral anterior temporal lobe, whose activity may be dynamically changed by the level of consolidation of face-name associations.

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.