Sleep, Torpor and Memory Impairment
From The Space Library
Author - S. Palchykova et al
Co-Author(s) - S. Palchykova; I. Tobler
JBIS Volume # - 59
Page # - 134-138
Year - 2006
Keywords - Daily torpor, sleep deprivation, object recognition memory, EEG, topography, hamster
JBIS Reference Code # - 2006.59.134
Number of Pages - 5
Abstract
It is now well known that daily torpor induces a sleep deficit. Djungarian hamsters emerging from this hypometabolic state spend most of the time in sleep. This sleep is characterized by high initial values of EEG slow-wave activity (SWA) that monotonically decline during recovery sleep. These features resemble the changes seen in numerous species during recovery after prolonged wakefulness or sleep deprivation (SD). When hamsters are totally or partially sleep deprived immediately after emerging from torpor, an additional increase in SWA can be induced. It has been therefore postulated, that these slow- waves are homeostatically regulated, as predicted by the two-process model of sleep regulation, and that during daily torpor a sleep deficit is accumulated as it is during prolonged waking. The predominance of SWA in the frontal EEG observed both after SD and daily torpor provides further evidence for the similarity of these conditions. It has been shown in several animal and human studies that sleep can enhance memory consolidation, and that SD leads to memory impairment. Preliminary data obtained in the Djungarian hamster showed that both SD and daily torpor result in object recognition deficits. Thus, animals subjected to SD immediately after learning, or if they underwent an episode of daily torpor between learning and retention, displayed impaired recognition memory for complex object scenes. The investigation of daily torpor can reveal mechanisms that could have important implications for hypometabolic state induction in other mammalian species, including humans.
To BUY this paper click here
JBIS is © 1934-2013 British Interplanetary Society - 
