article
Selective Coupling between Theta Phase and Neocortical Fast Gamma Oscillations during REM-Sleep in Mice
Fecha
2011Registro en:
TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. (2011)
Autor
Scheffzu¨ k, Claudia
Kukushka, Valeriy I.
Vyssotski, Alexei L.
Draguhn, Andreas
Tort, Adriano Bretanha Lopes
Brankacˇk, Jurij
Resumen
Background: The mammalian brain expresses a wide range of state-dependent network oscillations which vary in frequency
and spatial extension. Such rhythms can entrain multiple neurons into coherent patterns of activity, consistent with a role in
behaviour, cognition and memory formation. Recent evidence suggests that locally generated fast network oscillations can
be systematically aligned to long-range slow oscillations. It is likely that such cross-frequency coupling supports specific
tasks including behavioural choice and working memory.
Principal Findings: We analyzed temporal coupling between high-frequency oscillations and EEG theta activity (4–12 Hz) in
recordings from mouse parietal neocortex. Theta was exclusively present during active wakefulness and REM-sleep. Fast
oscillations occurred in two separate frequency bands: gamma (40–100 Hz) and fast gamma (120–160 Hz). Theta, gamma
and fast gamma were more prominent during active wakefulness as compared to REM-sleep. Coupling between theta and
the two types of fast oscillations, however, was more pronounced during REM-sleep. This state-dependent cross-frequency
coupling was particularly strong for theta-fast gamma interaction which increased 9-fold during REM as compared to active
wakefulness. Theta-gamma coupling increased only by 1.5-fold.
Significance: State-dependent cross-frequency-coupling provides a new functional characteristic of REM-sleep and
establishes a unique property of neocortical fast gamma oscillations. Interactions between defined patterns of slow and fast
network oscillations may serve selective functions in sleep-dependent information processing.