| dc.description | Abstract: Time estimation is a major cognitive ability that allows humans and other animals to
optimize behavioral functions. These activities require the skill to measure the elapsed
time in several intervals [12], and involve multiple cognitive processes like attention,
memory and decision making [47]. To assess this phenomenon, the most used procedure
is interval timing [20, 25, 29, 43] which studies how a time interval is perceived,
represented and estimated in a range of seconds to minutes [12].
Several studies have centered their attention on variables that can modulate time
perception, such as emotion-related arousal [18, 49] and attention [46]. Other time scales
of biological timing, like circadian or seasonal cycles, have also been proposed to
influence interval timing [3, 21, 24]. Indeed, recent research have demonstrated the effects
of the circadian clock on short-time estimation [1, 13]. Both the circadian oscillator and the
sleep homeostat [11] appear to influence the rate at which the pacemaker emits pulses,
evidenced in overproductions [48] .
The accuracy of timing performances can also be influenced by environmental variables
[22]. In this respect, the extreme photoperiod of Antarctica, with up to four months of
complete darkness (polar night) is an ideal experimental setting to determine the impact of
different zeitgebers on circadian human rhythms. Influences of mood state and fatigue on
time production task have also been reported [23]. Both variables, together with negative
affect and hostility, constitute some of the prevalent psychological symptoms during polar
expeditions [8, 38]. The impact of this context on cognitive processes is variable, with
reports of no changes [19, 55], increases [9] or decreases in performance [39, 42].
Thus, circadian rhythms and emotional processes have a key relevance in the cognitive
functions involved in time estimation. These factors are affected by extreme
photoperiodicity, isolation and confinement conditions found in Antarctica. However, there
is no evidence about how time estimation unfolds in this context. Therefore, the aim of this
study was to assess interval timing in a crew overwintering in Antarctica. Our hypothesis is
that polar night and isolation affect the cognitive processes required to estimate time
during an overwintering mission in Antarctica. Accordingly, we expect to find less accurate
performances and longer intervals due to the lack of natural light exposure and to
emotional variations associated with prolonged isolation and confinement. | |
