Abstracts

Rationale: Decision-making is related to the ability of postponing a reward considering a higher profit in the future. It can be considered a hot executive function. Although the presence of executive dysfunction is well-established in patients with temporal lobe epilepsy related to Hippocampal Sclerosis (TLE-HS), decision-making abilities has rarely been examined. The main aim of this study is to investigate the ability to delay gratification, a decision-making subdomain, in patients with intractable TLE-HS. A secondary aim is to verify the association of delay gratification performance and cool executive function tests.Methods: We evaluated 28 patients with TLE-HS (mean age 37.26 [±14.11]; 8 male) and their cognitive performance was compared to 26 healthy controls (mean age 31.69 [±9.74]; 10 male), without epilepsy and psychiatric disorders. Patients were assessed using the Delay Discounting Task (DDT) and tests of attention, shifting, inhibitory control and concept formation. The impact of epilepsy clinical variable such as age of onset, epilepsy duration, anti-epileptic drug use, history of status epilepticus and febrile seizures, and presence of generalized seizures. Statistical analysis was performed using oneway ANCOVA with years of education as a confounding factor.Results: Patients and controls demonstrated similar performance on the DDT showing a similar hyperbolic discount rate (k, amount of time that the subject accepted to delay his/her gratification for receiving a higher reward; p=0.789) and probability rate (h, amount of chance that the subject accepted to gamble for receiving a higher reward; p=0.753). Delay gratification was not related to any applied cool executive function tests (Digit Span, Stroop Color Test, Trail Making Test, Wisconsin Card Sorting Test and Conners' Continuous Performance Test). History of history of febrile seizures; presence of generalized seizures; and seizure frequency had a significant impact in DDT scores.Conclusions: Patients with intractable TLE-HS show unimpaired delay gratification abilities, being able to accept a higher delay and a lower amount of chance for receiving a higher reward in the future. Clinical variables related to the epilepsy severity impact the performance on delay gratification. The observed impairment on cool aspects of executive function is unrelated to the hot executive function abilities. Despite impairments on memory and cool executive functions, patients with TLE-HS have some aspects of decision-making process spared.