http://cogprints.org/8720/
Association of salivary-assessed oxytocin and cortisol levels with time of night and sleep stage
There have been proposals for REM to have a
function of emotional memory consolidation, and also for
REM sleep to be involved in the promotion of attachment
behaviour. The hormones cortisol and oxytocin, respec-
tively, may be involved in these proposed REM sleep
functions. However, there are conflicting reports on whe-
ther levels of cortisol differ between sleep stages when
time since sleep onset (SSO) is controlled, and virtually no
literature on whether levels of oxytocin differ between
sleep stages. This study thus investigated the changes in
levels of oxytocin (OT) and cortisol (CT) across the night,
and whether these levels differ between REM and N2 sleep
when time SSO is controlled. 20 participants (10 males, 10
females, mean age = 20.45, SD = 2.01) were awakened
10 min into REM and N2 sleep periods in the sleep laboratory and gave saliva samples which were assayed for
OT and CT. Levels of OT were relatively constant across
the night, whereas CT increased significantly. REM and N2
did not differ significantly neither for OT nor for CT. The
study has implications for models of sleep-dependent
memory consolidation that incorporate the late sleep
increase in cortisol as a functional component of memory
consolidation, and also for the medical diagnostic assaying
of OT during sleep.
Blagrove, M.
Fouquet, N. C.
Baird, A. L.
Pace-Schott, E. F.
Davies, A. C.
Neuschaffer, J. L.
Henley-Einion, J. A.
Weidemann, Christoph T.
Thome, J.
McNamera, P.
Turnbull, O. H.
Physiological Psychology
Psychobiology
M.
Blagrove
N. C.
Fouquet
A. L.
Baird
E. F.
Pace-Schott
A. C.
Davies
J. L.
Neuschaffer
J. A.
Henley-Einion
Christoph T.
Weidemann
J.
Thome
P.
McNamera
O. H.
Turnbull