Dementia, mild cognitive impairment and quantitative EEG in patients with Parkinson's disease.

The objective of this study was to evaluate relationships between quantitative EEG (qEEG) changes and cognitive disturbance (mild cognitive impairment or dementia) and the motor disturbance stage in Parkinson's disease (PD). Thirty-two PD patients (age = 67.2 +/- 10.0) and 26 normal subjects (age = 68.4 +/- 4.7) were assessed using a neurological evaluation, modified Hoehn and Yahr (HY) scale for PD, a Portuguese version of the CERAD neuropsychological battery (consortium to establish a registry for Alzheimer's disease) incorporating the Mini-mental Status Examination, Clinical Dementia Rating and an EEG analysis of absolute and relative band amplitude at rest. Four groups were compared: three with PD (7 patients with dementia, 10 with mild cognitive impairment and 15 with no cognitive disturbances) and the control group. The qEEG showed no significant differences between the control group and PD patients without cognitive disturbance. Abnormalities on the qEEG were essentially associated with the occurrence of mild cognitive impairment or dementia in patients with PD. There was an increase in the absolute and relative posterior theta amplitude in the groups with mild cognitive impairment or dementia and of the posterior absolute and relative delta amplitude in the group with dementia This study suggested qEEG as a possible physiological tool in the assessment of cognitive aspects in PD.

Benign childhood epilepsy with centrotemporal spikes: an ictal EEG.

Benign childhood epilepsy with centrotemporal spikes (BECTS) is common during childhood, but there are few reports in the literature recording the EEG during a seizure. We studied an 8-year-old boy with oropharyngeal seizures during wakefulness and sleep. Both his neuropsychomotor development and neurological examination were normal. While awake, the subjects's electroencephalogram (EEG) showed normal background activity and epileptiform activity characterized by spikes in the temporal regions (mid and anterior), central region of the right cerebral hemisphere and in the median central and parietal regions. During sleep, his EEG recorded an epileptic seizure that lasted 46 seconds. In the initial phase, the EEG showed an increase in the number of spikes with higher potential in the median central and parietal regions, followed by slow waves associated with the increase in slow waves in the right hemisphere. This was followed by a brief decrease in amplitude of the background activity, and then by rhythmic, diffuse discharges predominantly in the right centrotemporal region, of sharp waves at 12-13 Hz, with increasing potential. Slow waves of high amplitude then occurred for 5 seconds, and finally very high potential spikes reappeared in the central and temporal regions of the right cerebral hemisphere with normalization of the background activity. During these critical phases of the EEG, clonic lip movements and pouting could be observed with the mouth locked shut, associated with "throat noises," but there were no other motor manifestations. The child did not wake up during the seizure and there were no postictal signs or symptoms. Although there are some aspects in common in recordings of BECTS seizures, such as a reduction in amplitude followed by rhythmic discharges of increasing amplitude, differences exist that possibly correspond to the diverse characteristics of the electrical generators.