Time perception in patients with epilepsy who underwent anteromedial temporal lobectomy

• Grant number: 13/17225-5
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): December 01, 2013
• Effective date (End): November 30, 2015
• Field of knowledge: Health Sciences - Medicine - Medical Clinics
• Principal researcher: Benito Pereira Damasceno
• Grantee: Anna Clara Hebling Mitidieri
• Home Institution: Hospital de Clínicas (HC). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

The perception of time (PT) is a complex neurofunctional system consisting of different interconnected cerebral regions that process different components, namely: date orientation, sequence of events; discrimination of simultaneity and succession; building units of time, psychological time; conditioning time; conservation of watch speed; and contrast, production and reproduction durations. In this system, one can distinguish two main components: cortical areas responsible for sensory perceptions interconnected with the temporal limbic regions and ventral-medial frontal related processes like most elementary biological rhythms and neural conditioned reflexes to time and recording micro-intervals; and association cortex and their inter-connections hemispherical design which controls the time and duration of quantitative estimate. The neurofunctional PT system may be changed in epilepsy, being a chronic neurological syndrome characterized by temporary and reversible alteration of brain function caused by a disorganized electrical discharge that spreads throughout the brain and it is expressed by repeated seizures, presenting convulsion, behavior changes, motor symptoms and loss of consciousness. In adults, the most common type of epilepsy is temporal lobe epilepsy (TLE), usually associated with hippocampal atrophy, one of the most debilitating and often refractory to pharmacological treatment, but surgical treatment is beneficial for most patients. The temporal lobe can be functionally divided into two parts: (1) medial, including the hippocampus, playing an important role in episodic memory, autobiographical, coding, and temporal ordering of events, with the left side involved in verbal memory and the right side, in the visual-spatial memory; and (2) anterior, including the lateral temporal cortex, related to semantic memory. In summary, studies show that the perception of time and measurement results in a complex functional system, which comprises: the prefrontal cortex and premotor, temporal cortex, insula, basal ganglia, and cerebellum. Thus, the anteromedial temporal region (and hippocampal) tasks in PT are of great importance when patients undergoing surgical resection of this area are studied. PT was studied in patients with temporal lobectomy due to ELT, by evaluating patients and controls and the ability of temporal orientation, discrimination of durations, and memorization. In addition, to compare the performance between patients with surgical ablation on opposite sides (side?) tasks EN, and correlating the scores of these tests with other cognitive functions (counter-evidence). The study will include patients of both sexes, aged over 15 years, literate and who underwent anteromedial temporal lobectomy or amygdalohippocampectomy for treating unilateral TLE and are followed at Ambulatório de Epilepsia de Difícil Controle of HC- UNICAMP. All patients will undergo interviews and neurological examination, visual acuity, handedness test, evaluation of visual perception, and PT test - time orientation, comparison, production durations, and temporal ordering of events. This/they will be compared with temporal lobe resection patients and normal control subjects and patients together. "Chi-square" will be used to analyze the proportions, Student t-test, ANOVA and Tukey's test to compare means, and Pearson correlations for verification between demographic and cognitive variables. It is expected that the PT, in some of its components, is amended in epileptic patients with surgical lesions of anteromedial temporal lobectomy. And so, it is hoped to better understand the role of the anteromedial temporal lobe region, right and left, this cognitive function, as well as the difficulties of operating time of these patients.(AU)