Relationship between, sleep spindles and clinical recovery in patients with traumatic brain injury: a simultaneous EEG and MEG study.

Few methods can predict the prognosis and outcome of traumatic brain injury. Electroencephalographic (EEG) examinations have prognostic significance in the acute stage of posttraumatic coma, and some EEG variables have been correlated with outcome. Furthermore, spindle activity and reactivity in the acute stage have been associated with good recovery.

Relationships between sleep spindles and activities of the cerebral cortex after hemispheric stroke as determined by simultaneous EEG and MEG recordings.

This study aimed to determine the relationships between the amplitude and cortical-activating areas in each hemisphere for 14-Hz centro-parietal spindles to clarify the involvement of the cortex in the asymmetry of spindles after hemispheric stroke with putaminal or thalamic hemorrhage using simultaneous recording of the electroencephalogram and magnetoencephalogram. Spontaneous cortical activities during sleep stage 2 (spindles) were simultaneously recorded from 10 patients with putaminal or thalamic hemorrhage with a 60-channel electroencephalogram and a 306-channel whole-head magnetoencephalogram. Based on the frequencies and cortical distributions recorded with electroencephalogram, the 14-Hz centro-parietal and 12-Hz frontal spindles were differentiated.

Relationships between sleep spindles and activities of cerebral cortex as determined by simultaneous EEG and MEG recording.

The purpose of this study was to clarify the relationships between the distributions and cortical sources of two types of spindles in the magnetoencephalogram (MEG) and how cortical activating areas contribute to the distribution of spindles. Spontaneous activities during sleep stage 2 were recorded from 7 normal subjects by simultaneous EEG and MEG recordings. Two types of spindles with frequency-specific topographic differences (fast spindles and slow spindles) were defined by EEG, and, subsequently, the sources of spindles were estimated as equivalent current dipoles using MEG.