| dc.description.abstract | Operant extinction is learning to supress a previously rewarded behavior. It is known to
be strongly associated with the specific context in which it was acquired, which limits
the therapeutic use of operant extinction in behavioral treatments, e.g., of addiction.
We examined whether sleep influences contextual memory of operant extinction over
time, using two different recall tests (Recent and Remote). Rats were trained in an
operant conditioning task (lever press) in context A, then underwent extinction training in
context B, followed by a 3-h retention period that contained either spontaneous morning
sleep, morning sleep deprivation, or spontaneous evening wakefulness. A recall test
was performed either immediately after the 3-h experimental retention period (Recent
recall) or after 48 h (Remote), in the extinction context B and in a novel context C. The
two main findings were: (i) at the Recent recall test, sleep in comparison with sleep
deprivation and spontaneous wakefulness enhanced extinction memory but, only in the
extinction context B; (ii) at the Remote recall, extinction performance after sleep was
enhanced in both contexts B and C to an extent comparable to levels at Recent recall
in context B. Interestingly, extinction performance at Remote recall was also improved in
the sleep deprivation groups in both contexts, with no difference to performance in the
sleep group. Our results suggest that 3 h of post-learning sleep transiently facilitate the
context specificity of operant extinction at a Recent recall. However, the improvement
and contextual generalization of operant extinction memory observed in the long-term,
i.e., after 48 h, does not require immediate post-learning sleep. | |
