Neuropsychiatric Symptoms of Epilepsy

8 Epilepsy and Sleep: Close Connections and Reciprocal Influences
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Fig. 8.2 Sleep terror in a 7-year-old boy. The patient sits on his bed, opens his eyes, touches the
objects around him with his left hand looking around frightened, and then rapidly goes back to
sleep. Polysomnographic tracing during the event documents a rhythmic delta activity associated
with increased muscle tone and marked increase of heart rate
prolonging the event. Typical parasomnias resolve spontaneously with the patient
rapidly returning to sleep, with no recollection of the event in the morning.
Disorders of arousal tend to occur in the first part of the night, when NREM
stages 3 and 4 predominate, and may be triggered by a variety of factors including
sleep deprivation, a disruption to the sleep environment or sleep schedule, stress,
febrile illness, medications, alcohol, emotional stress in susceptible individuals or
sleep-disordered breathing [ 43 ]. Polysomnography during the events reveals a
rhythmic delta activity pattern associated with a marked increase in muscle tone,
and changes in respiratory and heart rates.
Arousal parasomnias may mimic epileptic seizures, namely Nocturnal Frontal
Lobe Seizures (NFLS), and the differential diagnosis can be challenging but can
usually be accomplished by attention to the description of the events, their frequency,
clustering, and timing in relationship to sleep onset [ 44 ]. Features that suggest an
NREM parasomnias rather than NFLS are a low rate of same-night recurrence of
the episodes, long duration, appearance within the first few hours of sleep (seizures
may occur throughout the night), and the characteristic motor pattern (parasomnias
are not stereotypical, and complex and repetitive behavior with abnormal movements,
such as dystonic and dyskinetic postures, are absent) [ 45 ]. Moreover, the