Contingent negative variation in Gilles de la Tourette syndrome.

The Contingent Negative Variation (CNV) may measure arousal and attention, and is affected by various dopaminergic disorders. We recorded CNVs in 12 patients fulfilling diagnostic criteria of Gilles de la Tourette Syndrome (TS). Ten of 12 patients were male, 10 had attention deficit disorder (ADD), and 3 also had obsessions and compulsions (OCD). Medication had been stopped or TS treatment not yet started. TS patients had higher CNV amplitude and more frequent postimperative negative variation than controls. CNV2 was enhanced in all TS patients, while CNV1 was attenuated in TS patients with ADD or OCD. This suggests that CNV may be increased in TS, mostly because of CNV2 and perhaps due to dopaminergic excess. CNV2, considered to reflect adrenergic arousal mechanisms, may be effected by neurobehavioral concomitants of TS. Neurophysiological categorization of TS patients may be possible and valuable.

Electroencephalography in childhood conduct and behavior disorders.

The pathophysiology of behavior disorders in children is controversial. In particular, the relationship of episodic behavior disturbance to epilepsy and chronic behavior problems to subclinical neurologic disorder has been debated. It has been suggested that EEG may assist in this sometimes difficult determination. We report on routine screening EEGs in children hospitalized over an 18-month period for behavior problems. Eighty-six children were admitted for conduct disorder, attention deficit hyperactivity disorder, or both. Seventy-eight tracings (91%) were normal or showed normal variant patterns. Eight records (9%) were abnormal, showing background slowing or paroxysmal discharges not associated with behavioral manifestations. None of these neurologically normal, nonretarded patients had epilepsy or other known cerebral disorder. This suggests that routine EEG screening may be of limited value in childhood behavior problems without clinical evidence of neurologic disorder.

Cassette EEG sleep recordings in Gilles de la Tourette syndrome.

Tourette syndrome (TS) patients often complain of sleep problems, and questionnaire studies indicate that sleep disturbance is frequent. Decreased slow wave sleep and increased awakenings have been reported in laboratory polysomnography in TS patients, and a serotoninergic disorder of arousal has been postulated. We recorded outpatient sleep in 20 patients newly diagnosed with TS utilizing a 4-channel cassette EEG system. The newly-diagnosed patients were predominantly male, and ranged in age from 10 to 36 years. Some had taken psychotropic medications in the past, but none had been treated systematically for TS. Seven patients had chronic tics only, 8 had tics and attention deficit-hyperactivity, and 5 had tics plus obsessions and compulsions. None had other medical, neurologic, or psychiatric disorders. All were nocturnal sleepers, and were recorded in their usual sleeping environments and routines. TS patients had reduced sleep, decreased sleep efficiency, increased awakenings, and decreased slow wave sleep. Tic patients had increased nocturnal awakenings and movements, particularly those who had tics during sleep. Sleep fragmentation and loss of slow wave sleep was most marked in TS patients with attention deficit-hyperactivity. Sleep latency was increased, REM sleep reduced, and REM sleep latency decreased in TS patients with obsessions and compulsions. These findings accord with previous reports of sleep disturbance in TS, and suggest that these disturbances may vary with TS symptoms. Chronic tics may persist in sleep and cause awakenings, TS with attention deficit may be associated with a disorder of arousal and alertness, and obsessions and compulsions may be manifestations of a biochemical disturbance involving paradoxical sleep.

Auditory evoked potentials in Gilles de la Tourette syndrome.

Gilles de la Tourette syndrome (TS) has been increasingly studied neurophysiologically as well as clinically. Obsessive-compulsive disorder (OCD) and attention deficit disorder (ADD) have been recognized to be part of the continuum of TS. We recorded brainstem auditory evoked potentials (BAEPs) and long-latency auditory event-related potentials (ERPs) in 20 patients with TS, 10 of whom had ADD and 6 OCD. TS patients with and without OCD and ADD did not differ in BAEP latencies, and no differences were found from normal controls. AEP latencies did not differ between TS patients and controls. TS patients with ADD had longer N100 and N200 latencies than TS patients without ADD, and TS patients with OCD had shorter N200 and P300 latencies. These findings suggest that TS is neurophysiologically heterogenous, and that TS patients with OCD or ADD may differ from those without.

Computerized EEG frequency analysis in Gilles de la Tourette syndrome.

EEG abnormality has been reported in Gilles de la Tourette Syndrome but not confirmed in later studies. We carried out computerized EEG frequency analysis in 30 patients with the disorder, using Nicolet Pathfinder II frequency analysis software, versions 1.2 and 3.1 EEG was recorded from 01-A1+A2, 02-A1+A2, Fz-A1+A2, F7-C3, F8-C4, T5-01, and T6-02 in Tourette Syndrome patients and controls. Controls were taking no medications, and drug therapy for Tourette Syndrome had been stopped or not yet initiated in the patient group. Modal alpha frequency (MAF), maximal alpha frequency (MxAF), and spectral edge frequency (SEF) was measured in occipital and frontal derivations in 24 patients and controls. Left frontal (MOLF) and right frontal (MORF) mobility was calculated in F7-C3 and F8-C4 in 21 patients and controls. No significant differences were found between Tourette Syndrome patients and controls by two-tailed t-test. These findings are in accord with recent evidence of little or no EEG abnormality in Tourette Syndrome patients as compared to normals.

Nocturnal sleep recording with cassette EEG in chronic headaches.

Many headache patients complain of poor sleep, and sleep disturbance has been shown to play a role in chronic pain. We recorded nocturnal sleep with a 4-channel cassette EEG monitoring device in 10 common migraine patients, 10 individuals with muscle contraction (tension) headache, and 10 chronic tension-vascular headache sufferers. Migraine patients had essentially normal sleep, although rapid eye movement (REM) sleep and REM latency were increased. Patients with tension headache had reduced sleep time and sleep efficiency, decreased sleep latency but frequent awakenings, increased nocturnal movements, and marked reduction in slow wave sleep, without change in REM sleep or latency. Mixed-element headaches with both tension and vascular features were associated with reduced sleep, increased awakening, diminished slow wave sleep, and REM sleep that was decreased in amount and reduced in latency. The findings suggest that patients with intermittent migraine may have minimal sleep disturbance, while chronic headache may be worsened by chronically poor sleep. Muscle contraction headache may be associated with frequent awakenings and decreased slow wave sleep similar to the sleep changes of fibrositis, while chronic tension-vascular headache may have a depressive substrate. Four-channel sleep recording may miss contributory sleep apnea, but nonetheless cassette EEG may facilitate outpatient evaluation of refractory headaches.

Outpatient sleep recording during antiepileptic drug monotherapy.

The effects of sleep and sleep deprivation on epilepsy are well known, but the effects of seizures and antiepileptic drugs (AEDs) on sleep have been less well studied. We recorded nocturnal sleep in 17 patients receiving antiepileptic monotherapy with ambulatory cassette EEG devices. Twelve patients had complex partial seizures and five had tonic-clonic convulsions. Two patients' seizures were largely nocturnal, and no seizures occurred during sleep recording. Five patients each were taking phenytoin (PHT), carbamazepine (CBZ), and valproate (VPA), and two were taking clonazepam (CZP), all with therapeutic serum levels and no toxic symptoms. Total sleep time was reduced, wakefulness increased, and sleep latency prolonged in partial seizures as compared with generalized epilepsy. REM sleep was reduced and its latency decreased in partial seizure patients. Both groups had decreased slow wave sleep; that of partial seizure patients was decreased more markedly. PHT increased sleep latency and decreased sleep time, and CBZ increased awakening and diminished slow wave and REM sleep. Patients taking VPA had slight reduction in slow wave sleep; those taking CPZ had decreased sleep and REM latencies. Epilepsy may affect nocturnal sleep, and the effects of partial and generalized seizure disorders may be different. AEDs may also have differential effects on nighttime sleep. These may prove important in the long-term management of epileptic patients.