Chapter 10 - Ablation/disconnection of cerebral tissue

Abstract

This chapter examines the effects of surgical ablation or disconnection of brain tissue on memory function. Sometimes the management of a patient's health may necessitate surgical intervention or a planned destruction of specific cerebral structures. Consequently, such necessary sectioning of the cerebral commissures, either to relieve epilepsy or to gain access to deep-seated lesions, has been found to have effects on memory functioning. Ablation of frontal tissue for the relief of epilepsy has resulted in a range of memory deficits, such as on tasks relating to recency judgments and memory for self-ordered responses. A probable explanation for such occurrences may be that distinct subgroups of memory disorder arise after frontal ablation, perhaps related to the locus and size of the resection. The removal of temporal lobe tissue, with or without the adjacent hippocampal resection, may result in significant memory impairment; in the course of temporal lobectomy, there is usually a deficit in performance from pre- to postoperative testing; this sometimes occurs in conjunction with improved performance on memory tasks related to the unoperated hemisphere.