Background: The neural correlates of recovery of unilateral neglect (ULN), as well as of other consequences of focal brain damage, are largely unknown. Functional neuroimaging methods (in particular, positron emission tomography [PET]) can be applied to the in vivo study of recovery mechanisms in neurologic patients. Objective: To evaluate the functional cerebral correlates of recovery from ULN in patients with right-sided lesions, with the use of a PET activation paradigm. Methods: Study of 3 patients with cerebrovascular lesions that involved corticosubcortical (patient 1) or subcortical (patients 2 and 3) areas of the right hemisphere. Unilateral neglect was tested twice, before and after completion of a 2-month rehabilitation program, after which all 3 patients showed considerable improvement. Similarly, 2 PET examinations were performed, before and after recovery, during the performance of a visuospatial task requiring the patients to detect and respond to visual targets moving on a computer screen from the right to the left visual hemifield (experimental condition). The cerebral activation was compared with a base line task in which subjects responded to a black dot flashing in a fixed position of the right hemifield. Results: The brain areas activated by the performance of the visuospatial task before and after recovery were compared. In all 3 patients, the regions notably more active after recovery were almost exclusively found in right-sided cortical areas and largely overlapped with those observed in a group of 4 normal subjects performing the same task. Other areas, which have been shown to be involved in attentional and oculomotor tasks in other PET studies, were also activated in patients with ULN. Conclusions: The behavioral recovery of ULN in these patients with predominantly subcortical lesions is mainly associated with cerebral activations in cortical regions similar to those observed in normal subjects. There is some evidence of functional reorganization in individual subjects, which involves other areas related to space representation and exploration

Pizzamiglio, L., Perani, D., Cappa, S., Vallar, G., Paolucci, S., Grassi, F., et al. (1998). Recovery of neglect after right hemispheric damage: H215O positron emission tomographic activation study. ARCHIVES OF NEUROLOGY, 55(4), 561-568 [10.1001/archneur.55.4.561].

Recovery of neglect after right hemispheric damage: H215O positron emission tomographic activation study

VALLAR, GIUSEPPE;PAULESU, ERALDO;FAZIO, FERRUCCIO
1998

Abstract

Background: The neural correlates of recovery of unilateral neglect (ULN), as well as of other consequences of focal brain damage, are largely unknown. Functional neuroimaging methods (in particular, positron emission tomography [PET]) can be applied to the in vivo study of recovery mechanisms in neurologic patients. Objective: To evaluate the functional cerebral correlates of recovery from ULN in patients with right-sided lesions, with the use of a PET activation paradigm. Methods: Study of 3 patients with cerebrovascular lesions that involved corticosubcortical (patient 1) or subcortical (patients 2 and 3) areas of the right hemisphere. Unilateral neglect was tested twice, before and after completion of a 2-month rehabilitation program, after which all 3 patients showed considerable improvement. Similarly, 2 PET examinations were performed, before and after recovery, during the performance of a visuospatial task requiring the patients to detect and respond to visual targets moving on a computer screen from the right to the left visual hemifield (experimental condition). The cerebral activation was compared with a base line task in which subjects responded to a black dot flashing in a fixed position of the right hemifield. Results: The brain areas activated by the performance of the visuospatial task before and after recovery were compared. In all 3 patients, the regions notably more active after recovery were almost exclusively found in right-sided cortical areas and largely overlapped with those observed in a group of 4 normal subjects performing the same task. Other areas, which have been shown to be involved in attentional and oculomotor tasks in other PET studies, were also activated in patients with ULN. Conclusions: The behavioral recovery of ULN in these patients with predominantly subcortical lesions is mainly associated with cerebral activations in cortical regions similar to those observed in normal subjects. There is some evidence of functional reorganization in individual subjects, which involves other areas related to space representation and exploration
Articolo in rivista - Articolo scientifico
Humans; Spatial Behavior; Case-Control Studies; Tomography, Emission-Computed; Brain Ischemia; Aged; Middle Aged; Neuropsychological Tests; Image Processing, Computer-Assisted; Male; Functional Laterality; Cognition Disorders
English
1998
55
4
561
568
none
Pizzamiglio, L., Perani, D., Cappa, S., Vallar, G., Paolucci, S., Grassi, F., et al. (1998). Recovery of neglect after right hemispheric damage: H215O positron emission tomographic activation study. ARCHIVES OF NEUROLOGY, 55(4), 561-568 [10.1001/archneur.55.4.561].
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/35092
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