The effects of antiepileptic drugs on startle reflex and memory in various epilepsy syndroms

Purpose: Increased brainstem excitability was not demonstrated in patients with epilepsy despite increased cortical neural activity. On the contrary, there are few studies showing that the connections of brainstem structures have been lost and some antiepileptic drugs have reduced brainstem excitability. There are many studies showing that memory processes in which brain stem reticular formation structures play an active role are impaired in epileptic patients. In this study, we aimed to investigate the effect of antiepileptic drugs and their relationship with emotion and memory by evaluating brainstem excitability with auditory startle reaction (ASR), which is a neurophysiological method. Methods: Fiftyseven individuals (53 patients with epilepsy, 4 using antiepiepstic drug for other diseases) (Female: 27, male: 30, mean age: 31,0811,42, age range: 18-65) in the patient group and 31 healthy subjects (Female: 20, male: 11, mean age: 36,5214,47, age range: 18-65) in the control group were participated in this study. The patients were divided into three groups as temporal, extratemporal lobe epilepsy and generalized onset epilepsy seizures. A separate grouping was done according to the antiepileptic drugs they used. ASR was recorded from on the nondominat side, orbicularis oculi, masseter, sternocloidomastoid, biceps brachii, abductor pollisis brevis, tibialis anterior muscles with acoustic stimulus each individual in the patient and control groups. The ASR latency, amplitude, duration, and probability of ASR were evaluated separately in each muscle. Minimal status test (MMST), Hamilton anxiety (HAS) and Hamilton depression scales (HDS) were evaluated. Results: ASR was hypoactive in the patient group compared to the control group. In patients with temporal lobe epilepsy, ASR was tended to be hypoactive compared to the control group. Carbamazepine did not have an effect on ASR, but ASR with valproic acid tended to be hypoactive. A positive correlation was found between HAS and ASR. There was no difference between HDS and MMDT scores. Discussion: Patients with epilepsy have hypoactive ASR. This feature is particularly evident in the temporal lob epilepsy group and in patients receiving VPA. Anxiety in epileptic patients increases the probability of occurrence of ASR. Keywords: Acoustic startle response (ASR), Epilepsy syndromes, Antiepileptic drugs, Memory