Clinical EEG and neuroscience
-
Gamma power and coherence in the electroencephalogram increase in healthy individuals in association with voluntary eye movements, saccades. Patients with unresponsive wakefulness syndrome show repetitive involuntary eye movements that are similar to saccades but progress at a much lower speed. In the present study, we explored the changes in gamma power and coherence related to these eye movements and investigated whether any relationship to the patients' clinical status could be found that would indicate first neurophysiological signs of recovery. ⋯ Based on the clinical status, we distinguished between recovering and chronic groups of patients. In comparison with the chronic group, the recovering group showed significantly higher gamma power over the posterior electrodes and significant higher values of coherence in the gamma-band activity during the presaccadic period of eye movements. We suggest that our findings on the onset of involuntary eye movements in the recovering group of patients with unresponsive wakefulness syndrome indicates a first neurophysiological sign of favorable prognosis.
-
This study evaluated the EEG findings of patients whose seizures were associated with a possible autoimmune etiology. Our aim was to find clues to distinguish patients with antineuronal antibodies (Ab) through EEG studies. We reviewed our database and identified antineuronal Ab positive epilepsy patients with or without autoimmune encephalitis. ⋯ EEG seems as a limited diagnostic tool in differentiating epilepsy and/or encephalopathy patients with a possible autoimmune etiology from those without. However, antineuronal Abs associated with encephalitis should be considered in the etiology of status epilepticus forms. A possible autoimmune etiology for seizures may be considered in the presence of continuous slow waves, FIRDA, and delta brush pattern in the EEG.