Neuropsychologia
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Body ownership for an artificial hand and the perceived position of one's own hand can be manipulated in the so-called rubber hand illusion. To induce this illusion, typically an artificial hand is placed next to the participant's body and stroked in synchrony with the real hand, which is hidden from view. Our first aim was to test if the crossmodal congruency task could be used to obtain a measure for the strength of body ownership in the rubber hand illusion. ⋯ Secondly, we tested the hypothesis that the lateral spatial distance between the real hand and artificial hand limits the rubber hand illusion. We found no lateral spatial limits for the rubber hand illusion created by synchronous stroking within reaching distances. In conclusion, the sense of ownership seems to be related to modulations of multisensory interactions possibly through peripersonal space mechanisms, and these modulations do not appear to be limited by an increase in distance between artificial hand and real hand.
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The present investigation concerns the multidimensionality of self-consciousness. I will specifically address this general issue by focusing on bodily self-consciousness and by considering how one is conscious of one's body through consciousness of both its physicality and its subjectivity. Here, physicality is defined as the belongingness to the physical world; subjectivity is defined as the fact of being a subject of conscious experience. ⋯ I argue that being conscious of one's body-as-subjective involves experiencing one's belongingness to the physical world; conversely, being conscious of one's body-as-physical involves experiencing it as one's own; either way, such forms of bodily self-consciousness involve experiencing both the subjectivity and the physicality of one's body. The hypothesis here is that the imbalance of these dimensions relative to each other would be pathological. I will thus underline the normal multidimensionality of bodily self-consciousness by considering its pathological breakdown as it happens in anorexia nervosa.
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Previous event-related potential (ERP) studies employing monetary gambling tasks have demonstrated that the brain responds differentially not only to one's own gain and loss but also to the others' gambling outcomes. Empathy and motivational significance are implicated in the processes of outcome evaluation. ⋯ The magnitude and latency of the effect on an early ERP component, the FRN, did not differ between the friend- and the stranger-observation conditions, whereas a late component, the P300, was modulated not only by reward valence but also by the interpersonal relationship between the observer and the other agent. These findings suggest that brain responses in outcome evaluation may be divided into an earlier semi-automatic process and a later cognitive appraisal process and that the interpersonal relationship comes into play mostly in the late attention-sensitive stage.
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Behavioral and functional neuroimaging studies indicate deficits in verbal working memory (WM) and frontoparietal dysfunction in individuals with dyslexia. Additionally, structural brain abnormalities in dyslexics suggest a dysconnectivity of brain regions associated with phonological processing. However, little is known about the functional neuroanatomy underlying cognitive dysfunction in dyslexia. ⋯ Within an "executive" bilateral frontoparietal network, dyslexics showed a decreased connectivity pattern comprising bilateral dorsolateral prefrontal and posterior parietal regions, while increased connectivity was found in the left angular gyrus, the left hippocampal cortex and the right thalamus. The functional connectivity strength in the latter regions was associated with WM task accuracy and with the numbers of errors during a spelling test. These data suggest functional connectivity abnormalities in two spatiotemporally dissociable brain networks underlying WM dysfunction in individuals with dyslexia.
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The influence of multiple mild traumatic brain injuries (mTBIs) on neuroelectric and task performance indices of the cognitive control of action monitoring was assessed in individuals with and without a history of concussion. Participants completed a standard clinical neurocognitive assessment and the error-related negativity of the response-locked event-related brain potential and task performance were measured during a modified flanker task. The findings suggested that those individuals with a history of mTBI demonstrate certain failures in cognitive control, and indicated that a greater number of mTBIs may relate to poorer integrity in the evaluation or signaling for control during instances of conflict. Given that these neuroelectric and behavioral differences exist in the absence of disparities in standard clinical assessment, the findings suggest that measures of cognitive control may be more sensitive to signs of chronic cognitive dysfunction resulting from mTBI.