Theta oscillation in the anterior cingulate and beta-1 oscillation in the medial temporal cortices: a human case report.
In previous studies we observed gamma (30-150 Hz) and beta-1 (10-20 Hz) oscillations in the medial temporal lobe (MTL) using subdural electrodes. The beta-1 was present during wake and REM sleep while gamma was present in all states. Recently we studied a patient (35 years M) with electrodes attached to the anterior cingulate cortex (ACC). This structure showed regular theta (5-6 Hz) oscillations. In the first recording, electrodes were attached to the MTL, that demonstrated the beta-1 and gamma oscillations. Two months later, electrodes were placed on orbitofrontal and ACC and an all night sleep recording was carried out. The ACC exhibited a highly regular and continuous theta oscillation during wakefulness and REM sleep, but not during NREM sleep. Since this same subject showed beta-1 oscillations in the MTL, it is probable that the theta in the ACC is independent of beta-1 in the MTL. This single case suggests the existence of two different frequency oscillators in the human limbic system. Elucidating their functional roles will be an interesting challenge for future studies.
Uchida
Sunao
S
Department of Sleep Disorders Research, Tokyo Institute of Psychiatry, 156-8585 Tokyo, Japan. sunao@uchidae.com
Maehara
Taketoshi
T
Hirai
Nobuhide
N
Kawai
Kensuke
K
Shimizu
Hiroyuki
H
D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology / Q000503:physiopathology; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000503:physiopathology*; D006179:Gyrus Cinguli / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D018782:Maze Learning; D009991:Oscillometry; D012895:Sleep, REM / Q000502:physiology; D013226:Status Epilepticus / Q000503:physiopathology* / Q000601:surgery; D013826:Theta Rhythm; D014584:User-Computer Interface; D014851:Wakefulness / Q000502:physiology