title: Sleep spindles in human prefrontal cortex: an electrocorticographic study.
abstract: To investigate the sleep spindle activity of the human prefrontal cortex (PFC), we simultaneously recorded whole nights of polysomnographic and electrocorticographic (ECoG) activities during the natural sleep of epileptic patients. Subjects were nine patients with intractable epilepsy who had subdural electrodes surgically attached to the orbital (seven cases), medial (three cases), or dorsolateral (two cases) PFC, and in one case to the frontal pole. To examine spindle frequencies, fast Fourier transformation (FFT) and auto-correlation analyses were performed on the PFC ECoG and Cz EEG data, primarily on epochs of stage 2 sleep. Lower sigma band ECoG oscillations of about 12 Hz were widely distributed across all prefrontal cortical areas including the frontal limbic regions, but none of the PFC sigma frequency peaks coincided with the faster (about 14 Hz) Cz EEG sleep spindles. Combining our results with anatomical and electrophysiological facts, it is suggested that the thalamofrontal circuit involving the rostral reticular and the mediodorsal nucleus of the thalamus is responsible for the generation of 12 Hz frontal spindles in humans.
authors.affiliation: Department of Psychiatry and Behavioral Science, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Motoaki
authors.initials: M
authors.lastname: Nakamura
authors.forename: Sunao
authors.initials: S
authors.lastname: Uchida
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Maehara
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kawai
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Hirai
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Nakabayashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Arakaki
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Okubo
authors.forename: Toru
authors.initials: T
authors.lastname: Nishikawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shimizu
mesh_terms: D000328:Adult; D004569:Electroencephalography; D004827:Epilepsy / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000502:physiology*; D012890:Sleep / Q000502:physiology*