Effect of stimulation of the human thalamus and parietal and temporal white matter on short-term memory.

Abstract

C LINICAL and experimental observations 7,~,:'~ indicate that the preservation of memory traces is dependent on specific cerebral mechanisms. Electrical excitation and lesions in the hippocampal formation 1,'-','~,8,2~ and mesial thalamus ~~,~'; have been related to memory deficits in man. Recent evidence 11 has also implicated the ventral lateral thalamus as an anatomic correlate for the storage of memory events. This report describes an attempt to determine whether other lateral thalamic and subcortical structures participate in memory functions. In a previous study 1~ a task of naming and short-term memory for pictorial memoranda was presented to patients with electrodes implanted in the thalamus for treatment of motion disorders. Electrical stimulation in the left pulvinar and deep parietal white substance in both hemispheres disrupted verbal behavior and elicited anomia. The effect of stimulation on the memory performance of these patients with thalamic electrodes and additional patients with temporal lobe electrodes is the subject of this report.