Post #1497817

i read a paper recently where a study done in rats found that caffeine made the brain's master clock more sensitive to entrainment by light inputs while adenosine made the brain less sensitive to light inputs, leading to changes in their sleep wake cycles. adenosine levels in the brain builds up the longer an individual is awake and generally inhibits processes related to wakefulness, which is why caffeine increases wakefulness to begin with, by acting as an antagonist. so it'd make sense that adenosine would also attenuate entrainment by light. a different paper found the same mechanism outlined in cloned human cells but i've been unable to find controlled trials done in humans so far. however this could mean that caffeine taken at the incorrect time, aside from promoting wakefulness, would directly interfere with the circadian rhythm by making the brain more susceptible to photo entrainment. but it also implies that the reverse, strategically timed caffeine dosing + light could help fix sleep wake cycles