Interval timing and circadian rhythms: Antarctica as a model of desynchronization

PLANO, S.; BELLONE, G.; TORTELLO, C.; BARBARITO, M.; FOLGUEIRA, A.; CUIULI, J.M.; VIGO, D.; AGOSTINO, P.; SIMONELLI, G.; GOLOMBEK, D.

Valpariso

Simposio; XIV Latin American Symposium on Chronobiology 2017; 2017

Introduction: Circadian rhythms seem to play a role in the modulation of time perception. Light is one of the main synchronizers of the circadian clock and studies are now focusing on its effect on time estimation. For example, constant light or dark conditions modify time perception in mice. In humans, diurnal variation in time productions correlate with circadian variations in core body temperature in well controlled lab studies. Antarctic provides a real-world and unexplored context to study the effect of desynchronization of the circadianclock on time perception. Objective: To explore interval timing in the crew of Belgrano II Argentine Antarctic station as a model of desynchronization of the circadian clock. Methods: A total of 13 subjects were assessed for interval timing in short (3s) and medium (6s) duration stimuli. Measures were taken during the morning and evening, five times along the year. Differences wereevaluated using repeated measures ANOVA. Results: Our results show significant variations for 3s during the morning (2595±123ms; 3022±161ms, 2987±197ms, 3229±203ms, 3449±249ms, p=0,004); 6s during the morning (5510±290ms; 5605±203ms, 6026±243ms, 6345±341ms, 6613±323ms, p=0,015); and 6s during the evening (5741±169ms, 6059±224ms, 6466±369ms, 6081±171ms, 5882±173ms, p=0,030). Discussion: While the short-interval productions during the morning increased progressively through the year, the medium-interval productions during morning and evening sessions increased during the winter polar night. The variations found in the short-interval productions may be related to isolation conditions, whereas the prolonged exposure to artificial light conditions during winter possibly modulates the seasonal differences observed in medium-interval roductions. (Sponsored by ANPCyT PICT Start-up 2013-0710, PIDDEF 2014/17n°06)