Category-specific Semantic Deficits Research Articles

Characterizing semantic memory loss: Towards the location of language breakdown

Patients suffering from various types of dementia usually present an impaired performance with specific categories like animals, furniture, etc. This impairment is known as category-specific semantic deficit and can provide us with vital information as to how the conceptual-semantic knowledge is stored and organized in the brain. Until date, no theoretical model has been able to appropriately account for the unsystematic and varied patterns of categoryspecific semantic deficits found so far. Moreover, there seems to be no correlation between the type of brain damage and the pattern of memory loss, nor can the latter be accounted for by any of the so far proposed models of conceptual knowledge representation and storage in the brain. Our purpose is to adapt and provide a theoretical model that builds on FunGramKB ontology and helps understand and properly interpret the available empirical data. The advantage that comes from the use of this complex theoretical model is that it will allow us to pinpoint the break of the conceptual chain, providing a more accurate measure of the location of the semantic memory loss.

Preserved cumulative semantic interference despite amnesia

Preserved cumulative semantic interference despite amnesia

"That thing in New York": Impaired naming vs. preserved recognition of unique entities following an anterior temporal lobe lesion

"That thing in New York": Impaired naming vs. preserved recognition of unique entities following an anterior temporal lobe lesion

Semantic memory: A feature-based analysis and new norms for Italian

Semantic norms for properties produced by native speakers are valuable tools for researchers interested in the structure of semantic memory and in category-specific semantic deficits in individuals following brain damage. The aims of this study were threefold. First, we sought to extend existing semantic norms by adopting an empirical approach to category (Exp. 1) and concept (Exp. 2) selection, in order to obtain a more representative set of semantic memory features. Second, we extensively outlined a new set of semantic production norms collected from Italian native speakers for 120 artifactual and natural basic-level concepts, using numerous measures and statistics following a feature-listing task (Exp. 3b). Finally, we aimed to create a new publicly accessible database, since only a few existing databases are publicly available online.

Body-part-specific Representations of Semantic Noun Categories

Word meaning processing in the brain involves ventrolateral temporal cortex, but a semantic contribution of the dorsal stream, especially frontocentral sensorimotor areas, has been controversial. We here examine brain activation during passive reading of object-related nouns from different semantic categories, notably animal, food, and tool words, matched for a range of psycholinguistic features. Results show ventral stream activation in temporal cortex along with category-specific activation patterns in both ventral and dorsal streams, including sensorimotor systems and adjacent pFC. Precentral activation reflected action-related semantic features of the word categories. Cortical regions implicated in mouth and face movements were sparked by food words, and hand area activation was seen for tool words, consistent with the actions implicated by the objects the words are used to speak about. Furthermore, tool words specifically activated the right cerebellum, and food words activated the left orbito-frontal and fusiform areas. We discuss our results in the context of category-specific semantic deficits in the processing of words and concepts, along with previous neuroimaging research, and conclude that specific dorsal and ventral areas in frontocentral and temporal cortex index visual and affective-emotional semantic attributes of object-related nouns and action-related affordances of their referent objects.

病初期の語義失語症例におけるカテゴリー特異的意味障害の経時的検討

ピック病が疑われる病初期の語義失語症例におけるカテゴリー特異的意味障害について検討した。症例は 63 歳右利き女性，喚語困難で発症し，呼称および聴理解障害の進行を呈した。失語症語彙検査の意味カテゴリー別名詞検査を用いて検討し，聴理解では，初回はすべてのカテゴリーで差がなく障害は軽度であった。16 ヵ月後には，「身体部位」「色」「屋内部位」「建造物」は比較的良好であったが，「野菜・果物」「植物」「動物」「道具」「乗り物」「加工食品」に低下がみられた。生物カテゴリーでは，すべてのカテゴリーにおける障害がみられたが，非生物カテゴリーにおいては，カテゴリーによる乖離がみられた。本症例のカテゴリー特異的意味障害より，意味処理系は生物と非生物カテゴリーに二分されていない可能性，さらに各カテゴリーの意味処理機構と左側頭葉前部との関連性が示唆された。

Contribución desde la neuropsicología al estudio de la memoria semántica

Semantic memory has been studied from various fields. The first models emerged from cognitive psychology from the hand of the division proposed by Tulving between semantic and episodic memory. Over the past thirty years there have been parallel developments in the fields of psycholinguistics, cognitive psychology and cognitive neuropsychology. The present work is to review the contributions that have emerged within the neuropsychology to the study of semantic memory and to present an updated overview of the points of consensus. First, it is defined the term semantics conceptually within the field of neuropsychology. Then, there is a dichotomy that passes through both psychological and neuropsychological models on semantic memory: the existence of modals versus amodal representations. Third, there are developed the main theoretical models in neuropsychology that emerged in an attempt to explain categoryspecific semantic deficits. Finally, more robust contributions and points that still generate some discussion are reviewed.

Category-specific semantic deficits in stroke patients: evidence from single-word comprehension.

Event Abstract Back to Event Category-specific semantic deficits in stroke patients: evidence from single-word comprehension. Krzysztof Jodzio1 and Daria Biechowska1* 1 University of Gdansk, Institute of Psychology, Poland Several neuropsychological studies have shown that patients with brain damage may demonstrate selective category-specific deficits of auditory comprehension. We report on an investigation of aphasic patients’ preserved ability to perform a semantic task on spoken words despite severe impairment in auditory comprehension, as shown by failure in matching spoken words to pictured objects. Twenty-six aphasic patients with impaired speech comprehension due to a left-hemisphere ischaemic stroke were examined. Six narrowly defined semantic categories for which dissociations have been reported are colors, body parts, animals, food, objects (mostly tools), and means of transportation. An analysis using one-way ANOVA with repeated measures in conjunction with the Lambda-Wilks Test revealed significant discrepancies among these categories in aphasic patients, who had much more difficulty comprehending names of colors than they did comprehending names of other objects. Animals were most often the easiest category to understand. The possibility of a simple explanation in terms of word frequency and/or visual complexity was ruled out. Evidence from the present study support the position that so called “global” aphasia is an imprecise term and should be redefined. These results are discussed within the connectionist and modular perspectives on category-specific deficits in aphasia. Conference: 41st European Brain and Behaviour Society Meeting, Rhodes Island, Greece, 13 Sep - 18 Sep, 2009. Presentation Type: Poster Presentation Topic: Poster presentations Citation: Jodzio K and Biechowska D (2009). Category-specific semantic deficits in stroke patients: evidence from single-word comprehension.. Conference Abstract: 41st European Brain and Behaviour Society Meeting. doi: 10.3389/conf.neuro.08.2009.09.182 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 10 Jun 2009; Published Online: 10 Jun 2009. * Correspondence: Daria Biechowska, University of Gdansk, Institute of Psychology, Gdansk, Poland, psykj@univ.gda.pl Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Krzysztof Jodzio Daria Biechowska Google Krzysztof Jodzio Daria Biechowska Google Scholar Krzysztof Jodzio Daria Biechowska PubMed Krzysztof Jodzio Daria Biechowska Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Concepts and Categories: A Cognitive Neuropsychological Perspective

One of the most provocative and exciting issues in cognitive science is how neural specificity for semantic categories of common objects arises in the functional architecture of the brain. More than two decades of research on the neuropsychological phenomenon of category-specific semantic deficits has generated detailed claims about the organization and representation of conceptual knowledge. More recently, researchers have sought to test hypotheses developed on the basis of neuropsychological evidence with functional imaging. From those two fields, the empirical generalization emerges that object domain and sensory modality jointly constrain the organization of knowledge in the brain. At the same time, research within the embodied cognition framework has highlighted the need to articulate how information is communicated between the sensory and motor systems, and processes that represent and generalize abstract information. Those developments point toward a new approach for understanding category specificity in terms of the coordinated influences of diverse regions and cognitive systems.

Category-specific semantic deficits in Alzheimer's disease: A semantic priming study

Category-specific semantic deficits in individuals suffering brain damage after relatively focal lesions provide an important source of evidence about the organization of semantic knowledge. However, whether Alzheimer's disease (AD), in which the brain damage is more widespread, affects semantic categories to a different extent is still controversial. In the present study, we assess this issue by means of the semantic priming technique. AD patients with a mild impairment of their semantic knowledge showed comparable priming effects to that of controls for the categories of animals and artifacts. Interestingly, however, patients with a moderate impairment of their semantic knowledge showed a normal priming effect for animals but a very reduced priming effect (if any) for artifacts. These results reveal that AD may affect the semantic knowledge of different semantic categories to a different extent. The implications of this observation for current theoretical accounts of semantic representation in the brain are discussed.

The interaction between semantic and the nonsemantic systems in reading: Evidence from Chinese

We report a Chinese-speaking patient WJX with left temporal lobe ischemic damage resulting in dementia. Similar to English speaking patients with this pathology, WJX showed impaired semantic system functioning together with a well preserved ability to read aloud Chinese characters including characters with unpredictable mappings between orthography and phonology—so called irregular characters. The summation hypothesis [Hillis, A. E., & Caramazza, A. (1991). Mechanisms for accessing lexical representations for output—evidence from a category-specific semantic deficit. Brain and Language, 40, 106–144; Hillis, A. E., & Caramazza, A. (1995). Converging evidence for the interaction of semantic and sublexical phonological information in accessing lexical representations for spoken output. Cognitive Neuropsychology, 12, 187–227] proposes that the good reading performance can be explained by the integration of a semantic route of reading and a nonsemantic route. Most Chinese characters contain components that can give a clue to the pronunciation (phonetic radical) and the meaning (semantic radical) of the character. We compared his comprehension and oral reading performance by varying the consistency of phonetic radicals and the transparency of semantic radicals. We observed an interaction between WJX's character comprehension and the consistency of the phonetic radical on reading performance; however, the transparency of semantic radicals had no effect on performance. We argue that this case report provides converging evidence for the principles of the summation hypothesis for reading.

Neural basis of category-specific semantic deficits for living things: evidence from semantic dementia, HSVE and a neural network model

Studies of patients with semantic impairments following brain damage offer key insights into the cognitive and neural organization of semantic memory. Especially important in this regard are studies of category-specific semantic impairment. We report a direct comparison of semantic deficits in two groups suffering from different diseases: semantic dementia (SD) and herpes simplex virus encephalitis (HSVE). Although pathology in both disorders is centred on the anterior temporal lobes bilaterally, category-specific semantic impairment is rarely observed in SD yet commonly found in HSVE. Using a combination of neuropsychology and computational neuroscience, we tested the possibility that category-specific deficits for living things depend not solely upon the location of damage within the cortical semantic network but also critically upon the type of impairment. When the semantic representations within the model are degraded or 'dimmed' then a generalized, global semantic impairment results (as found in SD) but when the representations are distorted then a category-specific pattern emerges (as per HSVE). Three novel predictions from this model were tested and confirmed, thereby adding weight to the hypothesis that both type and distribution of pathology can be critical in producing neuropsychological phenomena.

Analysis of the semantic representations of living and nonliving concepts: A normative study

Current feature-based semantic memory models assume that the semantic representations of concepts differ systematically across living and nonliving categories and that such differences account for the emergence of category-specific semantic deficits in brain-damaged people. To assess some of the different models' main assumptions about structural differences at the semantic feature level in the two major semantic domains, we administrated a feature-listing task to normal young volunteers on 64 concepts drawn from living and nonliving semantic categories. We investigated whether feature correlation, a variable with a crucial role in the emergence of category-specific deficits, should be computed as a concept-dependent or as a concept-independent measure, and we chose the former. We also addressed the issue of a psychological counterpart of feature production frequency. Finally, we analysed the database obtained from the feature-listing tasks, looked at cross-domain differences for correlation, feature frequency, distinctiveness, and feature type, and discussed the implications of these findings for current semantic memory models.

The Anatomy of Object Processing: The Role of Anteromedial Temporal Cortex

How objects are represented and processed in the brain remains a key issue in cognitive neuroscience. We have developed a conceptual structure account in which category-specific semantic deficits emerge due to differences in the structure and content of concepts rather than from explicit divisions of conceptual knowledge in separate stores. The primary claim is that concepts associated with particular categories (e.g., animals, tools) differ in the number and type of properties and the extent to which these properties are correlated with each other. In this review, we describe recent neuropsychological and neuroimaging studies in which we have extended our theoretical account by incorporating recent claims about the neuroanatomical basis of feature integration and differentiation that arise from research into hierarchical object processing streams in nonhuman primates and humans. A clear picture has emerged in which the human perirhinal cortex and neighbouring anteromedial temporal structures appear to provide the neural infrastructure for making fine-grained discriminations among objects, suggesting that damage within the perirhinal cortex may underlie the emergence of category-specific semantic deficits in brain-damaged patients.

Semantic processing of living and nonliving concepts across the cerebral hemispheres

Studies of patients with category-specific semantic deficits suggest that the right and left cerebral hemispheres may be differently involved in the processing of living and nonliving domains concepts. In this study, we investigate whether there are hemisphere differences in the semantic processing of these domains in healthy volunteers. Based on the neuropsychological findings, we predicted a disadvantage for nonliving compared to living concepts in the right hemisphere. Our prediction was supported, in that semantic decisions to nonliving concepts were significantly slower and more error-prone when presented to the right hemisphere. In contrast there were no hemisphere differences for living concepts. These findings are consistent with either differential representation or processing of concepts across right and left hemispheres. However, we also found a disadvantage for nonliving things compared to living things in the left hemisphere, which is not consistent with a simple representation account. We discuss these findings in terms of qualitatively different semantic processing in right and left hemispheres within the framework of a distributed model of conceptual representation.

The influence of semantic and morphological complexity of verbs on sentence recall: Implications for the nature of conceptual representation and category-specific deficits

One hundred and forty normal undergraduate students participated in a Proactive Interference (PI) experiment with sentences containing verbs from four different semantic and morphological classes (lexical causatives, morphological causatives, and morphologically complex and simplex perception verbs). Past research has shown significant PI build-up effects for semantically and morphologically complex verbs in isolation ( de Almeida & Mobayyen, 2004). The results of the present study show that, when embedded into sentence contexts, semantically and morphologically complex verbs do not produce significant PI build-up effects. Different verb classes, however, yield different recall patterns: sentences with semantically complex verbs (e.g., causatives) were recalled significantly better than sentences with semantically simplex verbs (e.g., perception verbs). The implications for the nature of both verb-conceptual representations and category-specific semantic deficits are discussed.

P2-210 Regional MR brain volumes in the prediction of cognitive decline in ad

P2-210 Regional MR brain volumes in the prediction of cognitive decline in ad

Heterogeneity is a Fact of Category-Specific Semantic Deficits. So? Comments on Rosazza, Imbornone, Zorzi, Farina, Chiavari, and Cappa (2003)

The Sensory/Functional Theory, until recently the received explanation of category-specific semantic deficits, has been shown to be at variance with various facts that have emerged about the nature of these deficits. In this context, Rosazza, Imbornone, Zorzi, Farina, Chiavari, and Cappa (2003: The Heterogeneity of Category-Specific Semantic Disorders: Evidence from a New Case. Neurocase, 9, 189–202.) report the case study of a patient, MA, with a purported category-specific semantic deficit for living things compared to nonliving things, and an associated modality-specific impairment that differentially affected visual/perceptual compared to functional/associative knowledge. While acknowledging that the Sensory/Functional Theory cannot account for the existence of category-specific semantic deficits, Rosazza and colleagues (2003) contend that “… the presence of a more severe loss of specific visual rather than functional knowledge could support an interpretation according to the Sensory/Functional Theory” [sic] (p. 200). Our comments are divided into two parts. First, we point out that there is an asymmetry between evidence and theory: if there is clear evidence that “disconfirms” a given theory, evidence that is consistent with the theory cannot be argued to support the theory. Second, we argue that the performance profile of MA could potentially be relevant to other interpretations of category-specific deficits but that theoretical interpretations of the performance profile of patient MA are undermined by a lack of methodological rigor, as well as the generally weak data associated with the case.

Heterogeneity is a Fact of Category-Specific Semantic Deficits. An Issue Worth Considering. Comments on Bradford Z. Mahon and Alfonso Caramazza (2003)

Heterogeneity is a Fact of Category-Specific Semantic Deficits. An Issue Worth Considering. Comments on Bradford Z. Mahon and Alfonso Caramazza (2003)

Category-specific Semantic Deficits do not Reflect the Sensory/Functional Organization of the Brain: A Test of the “Sensory Quality” Hypothesis

We report the performance of a herpes simplex encephalitis patient, EA, who shows a dissociation between poor performance for living things and spared performance for sensory quality categories, when appropriate measures are taken to control for baseline differences among categories in task difficulty and when we eliminate the contribution of visual processing deficits in the recognition of objects. This pattern of performance is problematic for theories of category-specific deficits that are based on the assumption that these deficits reflect selective damage to modality-specific semantic subsystems but is consistent with domain-specific accounts and theories based on the assumption that the structure of conceptual knowledge reflects the correlational structure among object properties.