**8. Effect of epilepsy on sleep**

The effect of epilepsy on sleep was first described in 1890 by Fere, based on clinical findings of difficulty falling asleep and impairing sleep efficiency. About two-third of patients suffering from epilepsy have sleep dysfunction [63]. Three main mechanisms that need to be considered regarding this topic are: 1. the epilepsy itself may be associated with sleep disturbance due to mechanisms intrinsic to the syndrome; 2. the effect of seizures on sleep architecture; and 3. the effect of AEDs on sleep.

Experimental amygdala kindling, an animal epilepsy model involving temporal structures, showed disturbed sleep patterns with sleep fragmentation and a shift toward lighter sleep [64]. In humans, patients with epilepsy have reduced NREM N2 and N3 sleep and REM sleep [65]. Sleep abnormalities seem to be more marked in patients with temporal lobe epilepsy compared to generalized epilepsies [15]. The limbic system participates in the neural networks underlying sleep organization, sleep induction, and arousal. **Table 2** shows the effects of epilepsy on seizures.

Patients suffering from nocturnal seizures show reduced sleep efficiency, increased time into REM period, and increased drowsiness [65]. The effects of AEDs on sleep will be discussed separately in the next section.


#### **Table 2.**

*Common effect of epilepsy on sleep.*
