Researchers have found that the body clock breaks down when light and temperature are out of sync, affecting activity levels.
Changes in light and darkness disrupt the human body clock causing ‘jet lag’. However, research on Drosophila (fruit flies) has found that changes in ambient temperature can also disrupt the body’s natural circadian rhythms, or body clock.
With daily temperature levels often closely linked to hours of sunlight, the researchers found that heat and light misalignment produced dramatic changes in the activity levels of fruit flies which are normally increasingly active throughout the 12 hours of daylight, peaking in the evening just before light and temperature levels drop.
As the effect of temperature on circadian rhythms has been less studied than the effect of light, the research, led by University College London (UCL), UK, and funded through the CLOCK MECHANICS project, could help in optimising working conditions such as regulating heating and air-conditioning to improve productivity, as well as improving people’s mental health.
In the journal Cell Reports, researchers said: ‘Our findings indicate a higher biological relevance for temperature effects on daily behavioural rhythms than previously appreciated.’
The experiments also found that a ‘moderate’ time lag, of around six hours difference between heat and light cues caused confusion in the natural clock function, leading to major disruptions to fly behaviour. Flies were only active during the six hours when it was both cold and light.
The CLOCK MECHANICS project has received just under €2m in EU funding and will be complete in August 2020.