Role of Left Anterior Temporal Lobe in Verbal Episodic Memory Performance

PSYC20006 Biological Psychology

Role of left anterior temporal lobe in verbal episodic memory performance

Aaron Wiseman

The University of Melbourne Student number: 586495

Tutor: Sacha Stokes Tutorial time: Thursdays 2:15pm

Word count: 2097

Abstract

The effects of a left anterior temporal lobe resection on verbal episodic memory performance was investigated in this study. Seven hundred participants performed a word free recall test similar to the Rey Auditory Verbal Learning Test, a recognised wordlist memory test originally developed by Rey (Salgado et al., 2011). Three hundred and fifty of the participants had undergone the resection as a prior treatment for left medial temporal lobe epilepsy, the remaining participants were healthy functioning adults and formed the control group. All participants were asked to freely recall as many words as possible from a wordlist following a distractor task. A between subjects t-test showed that the results were significant, supporting the hypothesis that the resection would lead to diminished performance on the test (i.e., recalled less words than the healthy controls). This showed that there was a negative affect on those with the resection to treat the epilepsy on verbal episodic memory.

2

Role of left anterior temporal lobe in verbal episodic memory performance

Having a properly functioning memory is crucial to a healthy human experience. Without it everyday tasks can be impaired, such as remembering what task was being performed. More serious memory impairment can cause interpersonal difficulties when a person struggles to remember their relationships. In memorising different types of information, there are distinctions made between procedural and declarative memory, with the former being concerned with learning that occurs with minimal conscious awareness, while the latter can be consciously accessed. Declarative memory is then subdivided into semantic and episodic memories. Semantic memory refers to general, generic knowledge, as opposed to episodic memory which relates to memorising events that happened personally to the individual (Baddeley, 2001).

The brain regions involved in processing of episodic memory have been identified through attempts to control temporal lobe seizures resulting from temporal lobe epilepsy– recurrent seizures with a localised origin in the temporal lobe. A surgical resection of the anterior temporal lobes has been found to result in impaired memory, including episodic memory (Lee, Yip, & Jones-Gotman, 2002; Rausch & Crandall, 1982). Along with the findings of a deteriorated episodic memory system following resection