Cognitive Neuropsychology最新文献

We investigated the representation and breakdown of verb knowledge employing different syntactic and semantic classes of verbs in a group of individuals with probable Alzheimer's Disease (pAD). In an action naming task with coloured photographs (Fiez & Tranel, 1997. Standardized stimuli and procedures for investigating the retrieval of lexical and conceptual knowledge for action. Memory and Cognition, 25(4), 543-569. https://doi.org/10.3758/BF03201129), pAD individuals were impaired for naming actions compared to objects. Verb tense was also affected, with simple-past (e.g., chopped) being more difficult to name than the gerundial form (e.g., chopping). Employing action-naming with short movies depicting events and states, we contrasted three verb classes based on their hypothetical structural and semantic/conceptual properties: argument structure, thematic structure, and conceptual templates. The three classes were: causatives (peel), verbs of perception (hear), and verbs of motion (run) Overall, results suggest that individuals with pAD are selectively impaired for verb tense and thematic assignment, but not conceptual-template complexity. Methodologically, we also show that dynamic scenes are more ecologically valid than static scenes to probe verb knowledge in AD.

Executive control is recruited for language processing, particularly in complex linguistic tasks. Although the issue of the existence of an executive control specific to language is still an open issue, there is much evidence that executively-demanding language tasks rely on domain-general rather than language-specific executive resources. Here, we addressed this issue by assessing verbal and non-verbal executive capacities in LG, an aphasic patient after a stroke. First, we showed that LG's performance was spared in all non-verbal tasks regardless of the executive demands. Second, by contrasting conditions of high and low executive demand in verbal tasks, we showed that LG was only impaired in verbal task with high executive demand. The performance dissociation between low and high executive demand conditions in the verbal domain, not observed in the non-verbal domain, shows that verbal executive control partly dissociates from non-verbal executive control. This language-specific executive disorder suggests that some executive processes might be language-specific.

The deficit in "interference control" found in children with Attention Deficit Hyperactivity Disorder (ADHD) could be due to two distinct processes, which are not disentangled in most studies: a larger susceptibility to activating prepotent response impulses and a deficit in suppressing them. Here, we investigated the effect of 1/ADHD and 2/ methylphenidate (MPH), on these two components of interference control. We compared interference control between untreated children with ADHD, children with ADHD under MPH, and typically developing children performing a Simon task. The main findings were that 1/ children with ADHD were more susceptible to reacting impulsively and less efficient at suppressing impulsive actions, and 2/ MPH improved the selective inhibition of impulsive actions but did not modify the strength of response impulse. This work provides an example of how pharmacological interventions and selective responses to them can be used to investigate and further our understanding of cognitive processing.

People with aphasia demonstrate impaired production of bound inflectional morphemes, such as noun plurals and possession. They often show greater difficulty in marking possession versus plurality. Using a new tool for eliciting language, the Morphosyntactic Generation test, we assessed people with primary progressive aphasia and those in the acute and chronic phase following left hemisphere stroke. Clinical profiles were associated with different strengths and weaknesses in language production. Performance of the plural was stronger than possessive in group analyses. However, some individuals demonstrated the inverse pattern of performance. These participants provide counter-evidence to the theory that difficulty with marking possessives is purely the result of their greater cognitive-linguistic complexity and support a functional double dissociation between possessives and plurals. The deficits resulted from morphosyntactic impairment. Future work is needed to understand why plural and possessive markers were differently sensitive to neurological disorders of language.

Developmental prosopagnosia (DP) is a syndrome characterized by lifelong impairment in face recognition in the absence of brain damage. A key question regarding DP concerns which process(es) might be affected to selectively/disproportionally impair face recognition. We present evidence from a group of DPs, combining an overview of previous results with additional analyses important for understanding their pattern of preserved and impaired perceptual abilities. We argue that for most of these individuals, the common denominator is a deficit in (rapid) processing of global shape information. We conclude that the deficit in this group of DPs is not face-selective, but that it may appear so because faces are more visually similar-and recognized at a more fine-grained level-than objects. Indeed, when the demand on perceptual differentiation and visual similarity are held constant for faces and objects, we find no evidence for a disproportionate deficit for faces in this group of DPs.

This study investigated the nature of graphemic buffer functioning and impairment, through analysis of the spelling impairment shown by GEC, a man with acquired dysgraphia and clear characteristics of graphemic buffer impairment. We discuss GEC's error patterns in relation to different processes of orthographic working memory. This is the first study to show the contribution of these processes in one individual through performance on different spelling tasks. GEC's spelling errors in writing to dictation showed a linear serial position effect, including deletions of final letters. These "fragment errors" can be explained as the result of information rapidly decaying from the buffer (reduced temporal stability). However, in tasks that reduced working memory demands, GEC showed a different error distribution that may indicate impairment to a different buffer process (reduced representational distinctiveness). We argue that different error patterns can be a reflection of subcomponents of orthographic working memory that can be impaired separately.

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.

Synaesthesia, a mixing of the senses, is more common in individuals with autism. Here, we review the evidence for the association between synaesthesia and autism with regard to their genetic background, brain connectivity, perception, cognitive mechanisms and their contribution to exceptional talents. Currently, the overlap between synaesthesia and autism is established most convincingly at the level of alterations in sensory sensitivity and perception, with synaesthetes showing autism-like profiles of sensory sensitivity and a bias towards details in perception. Shared features may include a predominance of local over global connectivity in the brain. When autism and synaesthesia co-occur in the same individual, the chance of developing heightened cognitive and memory abilities is increased. We discuss how the same theoretical models could potentially explain both conditions. Given the evidence, we believe the phenotypical overlap between autism and synaesthesia has been established clearly enough to invite future research to confirm overlapping mechanisms.

This study employed a multi-dimensional (i.e., orthographic, phonological, and semantic) and bi-level (i.e., character and radical) approach to analyze the character writing of 120 Hong Kong Chinese children with developmental dyslexia in Grades 2-5 and 120 typically developing age-matched controls. Relative to their typically developing peers, children with dyslexia were less sensitive to the positional and functional consistencies of sublexical radicals and exhibited prolonged use of phonology at the character level as grade-level advanced. Furthermore, the children with dyslexia relatively relied more on phonology at the radical level than younger, reading level-matched children. These results indicate the effects of implicit statistical learning on the development of Chinese character writing skills and suggest that the prolonged use and overreliance on phonology in character writing by Chinese children with dyslexia may reflect their difficulties in implicit statistical learning.