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T Feinberg

Publications and source records attributed to T Feinberg.

6 recordsLinked to original sources

Dissociation between linguistic and nonlinguistic gestural systems: a case for compositionality.

This paper addresses the issue of the separability of disorders of sign language from disorders of gesture and pantomime. The study of a left-lesioned deaf signer presents one of the most striking examples to date of the cleavage between linguistic signs and manual pantomime. The left-hemisphere lesion produced a marked sign language aphasia disrupting both the production and the comprehension of sign language. However, in sharp contrast to the breakdown of sign language, the ability to communicate in nonlinguistic gesture was remarkably spared. This case has important implications for our understanding of the neural mediation of language and gesture. We argue that the differences observed in the fractionation of linguistic versus nonlinguistic gesture reflect differing degrees of compositionality of systems underlying language and gesture. The compositionality hypothesis receives support for the existence of phonemic paraphasias in sign language production, illustrating structural dissolution which is absent in the production of pantomimic gesture. Understanding the neural encoding of compositional motoric systems may lead to a principled anatomical account of the neural separability of language and gesture. This case provides a powerful indication of the left hemisphere's specialization for language-specific functions.

Aphasia↗

Differential impact of right and left hemisphere lesions on facial emotion and object imagery.

Thirty-six patients with unilateral hemispheric lesions of the right hemisphere (RHD), left hemisphere (LHD), or no neurologic disease were evaluated on two tasks of visual imagery: one involved imagery for facial emotions and the other involved imagery for common objects. As a group, the RHD patients were more impaired on the emotional than the object imagery task, whereas the LHD patients showed the opposite pattern. Individual case analyses suggested that the RHD group consisted of different behavioural subtypes. One patient with a right inferior occipito-temporal lesion had a facial emotion imagery generation defect, other RHD patients displayed a facial affect agnosia (being impaired on emotional imagery and emotional perceptual tasks), while other RHD patients had perceptual defects with sparing of imagery performance. A final RHD group was globally impaired across all imagery and perceptual tasks. These findings support the hypothesis that the right hemisphere may contain a 'lexicon' of facial emotions. Furthermore, these findings argue against current views that it is exclusively the left or right hemisphere that mediates visual imagery. Rather, hemispheric asymmetries in imagery performance are to some extent material-representation specific and may arise when (a) the representations of objects/events to be imaged are differentially represented in the hemispheres, and/or (b) when the operations acting on these imaged events are differentially lateralized.

Aged↗

Apraxia after a superior parietal lesion.

We studied a patient who had unilateral (left) limb apraxia associated with a lesion of her right superior (Brodmann areas 5 and 7) and inferior parietal lobes. In monkeys areas 5 and 7 contain "hand-manipulation neurons" that are thought to be important in proprioceptive guidance. Therefore, we tested our patient with her eyes open and closed. Her left hand performance with pantonime, imitation, and use of actual objects dramatically deteriorated in the absence of visual guidance. In addition, although the patient did not have optic ataxia and had normal proprioception, she had difficulty using her left forelimb in tasks that require transcoding from a visual to a somatesthetic spatial coordinate system. We propose that each superior parietal lobe is not only responsible for transcoding from a visual-spatial code into a somatesthetic-spatial code but is also critical for transcoding spatial-temporal representations of skilled movement into a somatesthetic-spatial code.

Adult↗

Object reversals after parietal lobe infarction--a case report.

A case is described of a mixed manually dominant man with a right parietal infarction who demonstrated reversals in object manipulation. Although mirror reversals in parietal lobe dysfunction and right-left spatial reversal in conjunction with mirror writing have been reported previously, object and spatial reversal to this extent has not been reported. The theoretical implications of the absence of mirror writing here, in relation to side of brain lesion and handedness, are discussed.

Aged↗

Affective illness, dementia, and pseudodementia.

The differential diagnosis and treatment of pseudodementia, dementia, and depressive illness are receiving increased attention. The literature on this subject is reviewed, and four "ideal types" of patients spanning the spectrum of these illnesses are proposed for use when their distinction or association is at issue. Attempts by investigators to distinguish those groups are summarized, ad the importance of diagnostic clarity and patient selection for future research is emphasized.

Aged↗