1,721,020 research outputs found
In search of the disappeared half of it: 35 years of studies on representational neglect.
No full textOBJECTIVE:
Representational neglect (RN) is a neuropsychological deficit mostly occurring after right brain damage affecting the mental imagery domain. Patients suffering from RN are unable to represent, describe, or explore the contralesional side of their mental images. Since its first description in 1978, RN has been explored using different theoretical frameworks and experimental paradigms. After 35 years, the nature of its behavioral and anatomical correlates is still unclear.
METHOD:
We reviewed studies on RN published from 1978-2013 to systematize available knowledge and to shed light on future research directions.
RESULTS:
The huge variety of tests used to diagnose RN reflects the different clinical features of the deficit, which can compromise space sectors and memory storage, depending on the stimulus to be imagined, even in a dissociated fashion. RN has been frequently described after parietal, temporal, and frontal right brain lesions, even though reliable group studies are scanty.
CONCLUSION:
A number of priorities concerning RN were identified. Future studies might take into account several aspects of RN that are still poorly explored, starting from a more systematized investigation of RN using larger group studies. RESULTS might add pieces to the puzzle of spatial cognition and its neural basis in mental imagery, paving the way for tailored motor and cognitive rehabilitation program
Past present and future of neuroscience and law [Passato presente e futuro delle neuroscienze e del diritto]
No full textRecent years have been characterized by a gradual increase in the interaction between Law and Neuroscience, thanks to the advancement of Cognitive Neuroscience and to the advent of neuroimaging tools aimed at exploring the morphological and dynamic aspects of the brain. The fundamental question is to what extent the contribution of Neuroscience can change the behavior of lawyers. In this review, we summarize the current neuroscientific evidences and the expectations of the Law in respect of Neuroscience
The representation of peripersonal space around upper and lower limbs
No full textPeripersonal space (PPS), the space closely surrounding the body, is typically characterised by enhanced multisensory integration. Neurophysiological and behavioural studies have consistently shown stronger visuo-tactile integration when a visual stimulus is presented close to the tactually stimulate body part in near space (within PPS) than in far space. However, in the majority of these studies tactile stimuli were delivered to the upper limbs, torso and face. Therefore, it is not known whether the space surrounding the lower limbs is characterised by similar multisensory properties. To address this question we asked participants to perform two versions of the classic visuo-tactile crossmodal congruency task in which they had to perform speeded elevation judgements of tactile stimuli presented to the dorsum of the hand and foot while a simultaneous visual distractor was presented at spatially congruent or incongruent locations either in near or far space. In line with existing evidence, when the tactile target was presented to the hand the size of the crossmodal congruency effect (CCE) decreased in far as compared to near space suggesting stronger visuo-tactile multisensory integration within PPS. By contrast, when the tactile target was presented to the foot, the CCE was weaker for visual distractor in near than far space. A follow-up study confirmed that these results were not driven by the effector used to execute the response. These findings show systematic differences between the representation of PPS around upper and lower limbs, suggesting that the multisensory properties of the different body-part centred representations of PPS are likely to depend on the potential actions performed by the different body parts
Body ownership: When feeling and knowing diverge
Full text linkIndividuals with the peculiar disturbance of 'overcompleteness' experience an intense desire to amputate one of their healthy limbs, describing a sense of disownership for it (Body Integrity Identity Disorder - BIID). This condition is similar to somatoparaphrenia, the acquired delusion that one's own limb belongs to someone else. In ten individuals with BIID, we measured skin conductance response to noxious stimuli, delivered to the accepted and non-accepted limb, touching the body part or simulating the contact (stimuli approach the body without contacting it), hypothesizing that these individuals have responses like somatoparaphrenic patients, who previously showed reduced pain anticipation, when the threat was directed to the disowned limb. We found reduced anticipatory response to stimuli approaching, but not contacting, the unwanted limb. Conversely, stimuli contacting the non-accepted body-part, induced stronger SCR than those contacting the healthy parts, suggesting that feeling of ownership is critically related to a proper processing of incoming threats
PERIPERSONAL SPACE AROUND THE UPPER AND THE LOWER LIMBS
Full text linkPeripersonal space (PPS), the space closely surrounding the body, is typically characterised by enhanced multisensory integration. Neurophysiological and behavioural studies have consistently shown stronger visuo-tactile integration when a visual stimulus is presented close to the tactually stimulate body part in near space (within PPS) than in far space. However, in the majority of these studies tactile stimuli were delivered to the upper limbs, torso and face. Therefore, it is not known whether the space surrounding the lower limbs is characterised by similar multisensory properties. To address this question, we asked participants to complete two versions of the classic visuo-tactile crossmodal congruency task in which they had to perform speeded elevation judgements of tactile stimuli presented to the dorsum of the hand and foot while a simultaneous visual distractor was presented at spatially congruent or incongruent locations either in near or far space. In line with existing evidence, when the tactile target was presented to the hand, the size of the crossmodal congruency effect (CCE) decreased in far as compared to near space, suggesting stronger visuo-tactile multisensory integration within PPS. By contrast, when the tactile target was presented to the foot, the CCE decreased for visual distractors in near than far space. These findings show systematic differences between the representation of PPS around upper and lower limbs, suggesting that the multisensory properties of the different body-part centred representations of PPS are likely to depend on the potential actions performed by the different body parts
Is the desire for amputation related to disturbed emotion processing? A multiple case study analysis in BIID
Full text linkBody integrity identity disorder (BIID) is characterized by the overwhelming desire to amputate one or more healthy limbs or to be paraplegic. Recently, a neurological explanation of this condition has been proposed, in part on the basis of findings that the insular cortex might present structural anomalies in these individuals. While these studies focused on body representation, much less is known about emotional processing. Importantly, emotional impairments have been found in psychiatric disorders, and a psychiatric etiology is still a valid alternative to purely neurological accounts of BIID. In this study, we explored, by means of a computerized experiment, facial emotion recognition and emotional responses to disgusting images in seven individuals with BIID, taking into account their clinical features and investigating in detail disgust processing, strongly linked to insular functioning. We demonstrate that BIID is not characterized by a general emotional impairment; rather, there is a selectively reduced disgust response to violations of the body envelope. Taken together, our results support the need to explore this condition under an interdisciplinary perspective, taking into account also emotional connotations and the social modulation of body representation
Duckneglect: video-games based neglect rehabilitation.
No full textBACKGROUND:
Video-games are becoming a common tool to guide patients through rehabilitation because of their power of motivating and engaging their users. Video-games may also be integrated into an infrastructure that allows patients, discharged from the hospital, to continue intensive rehabilitation at home under remote monitoring by the hospital itself, as suggested by the recently funded Rewire project.
OBJECTIVE:
Goal of this work is to describe a novel low cost platform, based on video-games, targeted to neglect rehabilitation.
METHODS:
The patient is guided to explore his neglected hemispace by a set of specifically designed games that ask him to reach targets, with an increasing level of difficulties. Visual and auditory cues helped the patient in the task and are progressively removed. A controlled randomization of scenarios, targets and distractors, a balanced reward system and music played in the background, all contribute to make rehabilitation more attractive, thus enabling intensive prolonged treatment.
RESULTS:
Results from our first patient, who underwent rehabilitation for half an hour, for five days a week for one month, showed on one side a very positive attitude of the patient towards the platform for the whole period, on the other side a significant improvement was obtained. Importantly, this amelioration was confirmed at a follow up evaluation five months after the last rehabilitation session and generalized to everyday life activities.
CONCLUSIONS:
Such a system could well be integrated into a home based rehabilitation system
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