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Francesco Tomaiuolo - One of the best experts on this subject based on the ideXlab platform.
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Selective Deficit of spatial short-term memory: Role of storage and rehearsal mechanisms.
Cortex, 2014Co-Authors: Sonia Bonnì, Roberta Perri, Lucia Fadda, Francesco Tomaiuolo, Giacomo Koch, Carlo Caltagirone, Giovanni Augusto CarlesimoAbstract:We report the neuropsychological and MRI investigation of a patient (GP) who developed a Selective impairment of spatial short-term memory (STM) following damage to the dorso-mesial areas of the right frontal lobe. We assessed in this patient spatial STM with an experimental procedure that evaluated immediate and 5-20 s delayed recall of verbal, visual and spatial stimuli. The patient scored significantly worse than normal controls on tests that required delayed recall of spatial data. This could not be ascribed to a Deficit of spatial episodic long-term memory because amnesic patients performed normally on these tests. Conversely, the patient scored in the normal range on tests of immediate recall of verbal, visual and spatial data and tests of delayed recall of verbal and visual data. Comparison with a previously described patient who had a Selective Deficit in immediate spatial recall and an ischemic lesion that affected frontal and parietal dorso-mesial areas in the right hemisphere (Carlesimo GA, Perri R, Turriziani P, Tomaiuolo F, Caltagirone C. Remembering what but not where: independence of spatial and visual working memory in the human brain. Cortex. 2001 Sep; 37(4):519-34) suggests that the right parietal areas are involved in the short-term storage of spatial information and that the dorso-mesial regions of the right frontal underlie mechanisms for the delayed maintenance of the same data.
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Selective Deficit of mental visual imagery with intact primary visual cortex and visual perception
Cortex, 2008Co-Authors: Valentina Moro, Francesco Tomaiuolo, Giovanni Berlucchi, Jason P Lerch, Salvatore Maria AgliotiAbstract:There is a vigorous debate as to whether visual perception and imagery share the same neuronal networks, whether the primary visual cortex is necessarily involved in visual imagery, and whether visual imagery functions are lateralized in the brain. Two patients with brain damage from closed head injury were submitted to tests of mental imagery in the visual, tactile, auditory, gustatory, olfactory and motor domains, as well as to an extensive testing of cognitive functions. A computerized mapping procedure was used to localize the site and to assess the extent of the lesions. One patient showed pure visual mental imagery Deficits in the absence of imagery Deficits in other sensory domains as well as in the motor domain, while the other patient showed both visual and tactile imagery Deficits. Perceptual, language, and memory Deficits were conspicuously absent. Computerized analysis of the lesions showed a massive involvement of the left temporal lobe in both patients and a bilateral parietal lesion in one patient. In both patients the calcarine cortex with the primary visual area was bilaterally intact. Our study indicates that: (i) visual imagery Deficits can occur independently from Deficits of visual perception; (ii) visual imagery Deficits can occur when the primary visual cortex is intact and (iii) the left temporal lobe plays an important role in visual mental imagery.
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Selective Deficit for people s names following left temporal damage an impairment of domain specific conceptual knowledge
Cognitive Neuropsychology, 2000Co-Authors: Gabriele Miceli, Rita Capasso, Antonio Daniele, Teresa Esposito, Marina Magarelli, Francesco TomaiuoloAbstract:As a consequence of a head trauma, APA presented with Selective anomia for the names of familiar people, in the absence of comparable disorders for common names and other proper names. Face recognition was normal; and naming performance was unaffected by stimulus and response types. Selective proper name anomia was not due to effects of frequency of usage or of age of acquisition, or to Selective memory/learning Deficits for the names of people. Even though APA was able to provide at least some information on many celebrities whom she failed to name, she was clearly impaired in all tasks that required full conceptual information on the same people (but she performed flawlessly in similar tasks that involved common names). This pattern of performance indicates that in our subject the inability to name familiar persons results from damage to conceptual information. It is argued that detailed analyses of conceptual knowledge are necessary before it is concluded that a subject with proper name anomia suffers ...
Jean-denis Degos - One of the best experts on this subject based on the ideXlab platform.
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Selective Deficit ofvisual size perception: two cases ofhemimicropsia
1994Co-Authors: L Cohen, C Meyrignac, Stanislas Dehaene, Jean-denis DegosAbstract:Hemimicropsia isa raredisorder of visualperception characterised by an apparent reduction ofthesizeofobjects whenpresented inonehemifield. We reporttwo casesof hemumicropsia resulting fromfocal brainlesions. The first patient wasanartteacher andcould accurately depicthisabnormalvisual perception. Hesubsequently diedandhis brainwasexamined postmortem.Inthe secondpatient, micropsia wasassessed by a quantified sizecomparison task. The sizeofa givenobject isnormally perceived asconstant acrossanyspatial position. Hemimicropsia may thusbe considered alimited violation ofthesize constancyprinciple. Behavioural and anatomical dataarediscussed inrelation totheneural basisofvisual object per- ception inhumans. (7Neurol Neurosurg Psychiatry 1994;57:73-78)
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Selective Deficit of visual size perception: Two cases of hemimicropsia
Journal of Neurology Neurosurgery and Psychiatry, 1994Co-Authors: L Cohen, C Meyrignac, F Gray, Stanislas Dehaene, Jean-denis DegosAbstract:Hemimicropsia is a rare disorder of visual perception characterized by an apparent reduction of the size of objects when presented in one hemifield. We report two cases of hemimicropsia resulting from focal brain lesions. The first patient was an art teacher and could accurately depict his abnormal visual perception. He subsequently died and his brain was examined post mortem. In the second patient, micropsia was assessed by a quantified size comparison task. The size of a given object is normally perceived as constant across any spatial position. Hemimicropsia may thus be considered a limited violation of the size constancy principle. Behavioural and anatomical data are discussed in relation to the neural basis of visual object perception in humans.
Steven Z. Rapcsak - One of the best experts on this subject based on the ideXlab platform.
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source memory in the real world a neuropsychological study of flashbulb memory
Journal of Clinical and Experimental Neuropsychology, 2005Co-Authors: Patrick S R Davidson, Shaun P Cook, Elizabeth L Glisky, Mieke Verfaellie, Steven Z. RapcsakAbstract:A flashbulb memory (FM) is a vivid, enduring memory for how one learned about a surprising, shocking event. It thus involves memory for the source of event information, as opposed to memory for the event itself. Which brain regions are involved in FM, however, is uncertain. Although medial temporal lobe/diencephalic (MTL/D) damage impairs content or item memory, frontal lobe (FL) damage has been associated with impaired source memory. One would therefore expect that FM should depend on the FLs, although two recent reports do not support this idea. In the current study, we examined memory for the events of September 11th, and memory for the source of that information, in MTL/D patients, FL patients, and healthy subjects. Only the MTL/D patients were impaired in long-term memory for the event itself, measured after a 6 month retention interval. The FL patients, on the other hand, showed a Selective Deficit in source memory, although their memory for the target event was unimpaired. MTL/D and FL structures appear to play different roles in memory for flashbulb events.
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Selective Deficit of praxis imagery in ideomotor apraxia
Neurology, 1997Co-Authors: Cynthia Ochipa, Leslie Gonzalez J Rothi, Dawn Bowers, Lynn M. Maher, Steven Z. Rapcsak, Kenneth M. HeilmanAbstract:We studied imagery for learned, skilled movements (praxis imagery) in a patient with severe ideomotor apraxia and intact language abilities. This patient, who made predominantly spatial and movement errors when performing transitive movements demonstrating the use of tools (transitive gestures), was also impaired in her ability to answer imagery questions about joint movement or the spatial position of the hands during action. However, visual object imagery was spared. The finding of parallel praxis production and praxis imagery Deficits in this patient suggests that the same representations used for gesture production are also activated during imagery of motor acts. Our findings also suggest that certain aspects of motor imagery may be dissociable from general object imagery.
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Selective Deficit of praxis imagery in ideomotor apraxia
Annual meeting of the International Neuropsychological Society, 1997Co-Authors: Cynthia Ochipa, Leslie Gonzalez J Rothi, Dawn Bowers, Lynn M. Maher, Steven Z. Rapcsak, Kenneth M. HeilmanAbstract:Article abstract-We studied imagery for learned, skilled movements (praxis imagery) in a patient with severe ideomotor apraxia and intact language abilities. This patient, who made predominantly spatial and movement errors when performing transitive movements demonstrating the use of tools (transitive gestures), was also impaired in her ability to answer imagery questions about joint movement or the spatial position of the hands during action. However, visual object imagery was spared. The finding of parallel praxis production and praxis imagery Deficits in this patient suggests that the same representations used for gesture production are also activated during imagery of motor acts. Our findings also suggest that certain aspects of motor imagery may be dissociable from general object imagery.
Gordon H Bower - One of the best experts on this subject based on the ideXlab platform.
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reactivating a reactivation theory of implicit memory
Consciousness and Cognition, 1996Co-Authors: Gordon H BowerAbstract:Implicit and explicit memory tasks are interpreted within a traditional memory theory that distinguishes associations between different classes of memory units (sensory features, logogens, imagens, concepts, context tags). Associations from specific sensory features to logogens are strengthened by perceptual experiences, leading to specific perceptual priming. Associations among concepts are strengthened by use, leading to specific conceptual priming. Activating associations from concepts to logogens leads to semantic and associative priming. Item presentation also establishes a new association from it to a representation of the personal context, comprising an ‘‘episodic memory.’’ Such contextual associations play a major role in explicit memory tasks such as recall or recognition. A critical assumption of the theory is that presentation of a given item strengthens its sensory and contextual associations independently; this permits the theory to explain various dissociations of implicit and explicit memory measures. Furthermore, by assuming that brain-injured patients with global amnesia have a Selective Deficit in establishing novel associations to the context, the theory can explain their Deficits in explicit memory along side their intact implicit memory. © 1996 Academic Press, Inc.
L Cohen - One of the best experts on this subject based on the ideXlab platform.
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Selective Deficit ofvisual size perception: two cases ofhemimicropsia
1994Co-Authors: L Cohen, C Meyrignac, Stanislas Dehaene, Jean-denis DegosAbstract:Hemimicropsia isa raredisorder of visualperception characterised by an apparent reduction ofthesizeofobjects whenpresented inonehemifield. We reporttwo casesof hemumicropsia resulting fromfocal brainlesions. The first patient wasanartteacher andcould accurately depicthisabnormalvisual perception. Hesubsequently diedandhis brainwasexamined postmortem.Inthe secondpatient, micropsia wasassessed by a quantified sizecomparison task. The sizeofa givenobject isnormally perceived asconstant acrossanyspatial position. Hemimicropsia may thusbe considered alimited violation ofthesize constancyprinciple. Behavioural and anatomical dataarediscussed inrelation totheneural basisofvisual object per- ception inhumans. (7Neurol Neurosurg Psychiatry 1994;57:73-78)
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Selective Deficit of visual size perception: Two cases of hemimicropsia
Journal of Neurology Neurosurgery and Psychiatry, 1994Co-Authors: L Cohen, C Meyrignac, F Gray, Stanislas Dehaene, Jean-denis DegosAbstract:Hemimicropsia is a rare disorder of visual perception characterized by an apparent reduction of the size of objects when presented in one hemifield. We report two cases of hemimicropsia resulting from focal brain lesions. The first patient was an art teacher and could accurately depict his abnormal visual perception. He subsequently died and his brain was examined post mortem. In the second patient, micropsia was assessed by a quantified size comparison task. The size of a given object is normally perceived as constant across any spatial position. Hemimicropsia may thus be considered a limited violation of the size constancy principle. Behavioural and anatomical data are discussed in relation to the neural basis of visual object perception in humans.