An investigation of implicit memory through left temporal lobectomy for epilepsy

Does epilepsy differentially affect different types of memory?

Despite the recognition that epilepsy can substantially disrupt memory, there are few published accounts of whether and how this disruption varies across different types of memory and/or different types of epilepsy. This review explores four main questions: (1) Are working, episodic and semantic memory differentially affected by epilepsy? (2) Do various types of epilepsy, and their treatment, have different, specifiable effects on memory? (3) Are the usual forms of neuropsychological assessments of memory - many or most designed for other conditions - appropriate for patients with epilepsy? (4) How can research on epilepsy contribute to our understanding of the neuroscience of memory? We conclude that widespread and multifactorial problems are seen in working memory in all patient groups, while patients with temporal lobe epilepsy seem particularly prone to episodic memory deficit, and those with frontal lobe epilepsy to executive function deficits that may in turn impair semantic control. Currently, it is difficult to make individual patient predictions about likely memory deficits based on seizure aetiology and type, but it is possible to guide and tailor neuropsychological assessments in an individualised way. We make recommendations for future directions in validating and optimising neuropsychological assessments, and consider how to approach effective shared decision making about the pros and cons of seizure treatment strategies, especially at crucial educational stages such as adolescence.

Aspects of Oral Language, Speech, and Written Language in Subjects with Temporal Lobe Epilepsy of Difficult Control

Introduction About 50 million people have epilepsy and 30% of them have epilepsy that does not respond to properly conducted drug treatment.

Objective Verify the incidence of language disorders in oral language, speech, and written language of subjects with difficult to control temporal lobe epilepsy (TLE) and compare the occurrence of these disorders in subjects before and after surgery.

Methods Cross-sectional study with quantitative analysis, exploratory type. A questionnaire for data collection was administered covering the following aspects: oral language, speech complaints, and writing production and comprehension. Criteria for inclusion of subjects were a diagnosis of TLE refractory to drug treatment and at least 4 years of schooling.

Results The sample of 63 patients with TLE was divided into two groups: presurgical (n = 31) and postsurgical (n = 32). In the postsurgical group, there was a higher frequency of left lobectomy (75%) than right (25%).

Conclusion Statistical analysis was performed with the chi-square test (significance level of 0.05). Complaints related to speech-language attention were more predominant in postsurgical subjects. Analysis of oral language, speech, and written language in subjects with epilepsy who underwent temporal lobectomy or not showed findings consistent with symptoms related to transient aphasia, with the presence of paraphasias, as well as changes in speech prosody and melody. These symptoms appeared more associated with recurrence after having a temporal lobectomy.