The relationship between rhythmic activities during a mental task and sleep spindles: a correlative analysis.
In a previous study, we suggested that the characteristics of theta, alpha, and beta rhythms during a mental task were similar to those during sleep. Building upon the previous data, correlations between rhythmic activities during a mental task and during sleep were investigated in the present study. Patterns of correlation and no correlation between rhythmic activities during the mental task were similar to those during sleep for subjects with and without frontal midline theta (Fmtheta) activity. In the Fmtheta group, there were no correlations between rhythmic activities in the two situations, while in the non-Fmtheta subjects, theta and alpha rhythms showed a positive correlation with one another, and theta and beta rhythms correlated negatively during sleep. In both groups, there were many correlations between rhythmic activities during the mental task and those in Sleep Stage 2, while there were few correlations between rhythmic activities during the mental task and those in other sleep stages. These results suggest that the mechanism generating rhythmic activities during the appearance of rhythmic activities induced by a mental task may be closely related to those of rhythmic activities during sleep, and that the membrane potentials in reticular thalamic (RE) neurons during the appearance of rhythmic activities induced by a mental task may be nearly equivalent to that in Sleep Stage 2, and that the correlation pattern between the rhythmic activities in each group may be well explained by the appearance pattern of each rhythm in the previous report.
Department of Neuropsychiatry, Yamaguchi University School of Medicine, Ube, Japan.
Masatomo
M
Suetsugi
Yasushi
Y
Mizuki
Itsuko
I
Ushijima
Yoshifumi
Y
Watanabe
D000328:Adult; D000513:Alpha Rhythm / Q000379:methods / Q000706:statistics & numerical data; D001611:Beta Rhythm / Q000379:methods / Q000706:statistics & numerical data; D004569:Electroencephalography / Q000379:methods / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008606:Mental Processes / Q000502:physiology*; D017286:Polysomnography / Q000379:methods / Q000706:statistics & numerical data; D012890:Sleep / Q000502:physiology*; D013223:Statistics as Topic; D013826:Theta Rhythm / Q000379:methods / Q000706:statistics & numerical data