Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

A new study from the Vyazovskiy group suggests that how and where we spend our time while awake impacts how much we need to sleep - it does not only depend on how long we are awake.

The prevailing notion is that our sleep habits are hard-wired in some way, or genetically determined, and that all animals, including humans, have to perform a certain, non-negotiable amount of sleep every day. To this end, major research efforts in the last few decades have been focused on investigating the underlying biology of "sleep need", targeting a broad range of molecules, physiological processes or brain areas. However, according to DPAG’s lead sleep researcher Associate Professor Vladyslav Vyazovskiy: “What we tend to forget is that wakefulness and sleep are defined, by and large, by the interaction of the organism with its environment. Consistently, evidence accumulates that "sleep need" can vary greatly depending on external conditions or other homeostatic drives, in addition to the genetic makeup.”

A new study from the Vyazovskiy lab supports this view. The study, led by DPhil student Linus Milinski, addresses whether changes in an animal's environment would affect its wake behaviours, and whether this, in turn, would affect its subsequent sleep. The team’s main experiment trained mice on a simple ‘nose poke’ task, using a touchscreen operant chamber. Unexpectedly, the animals sometimes performed the task, voluntarily, for many hours in a row, even during the day, which is a habitual sleep time in laboratory mice. Professor Vyazovskiy said: “We therefore hypothesised that certain wake behaviours may slow down the accumulation of ‘tiredness’ during continuous waking, resulting in a reduced sleep need.” Consistent with this hypothesis, the researchers found that during subsequent sleep, EEG slow waves, an established marker of homeostatic sleep need, were markedly lower after wake dominated by a simple task performance, when compared to wake spent in an enriched environment.

While further research is required to further our understanding of how sleep is affected by wake activities, the study concludes that wake ‘quality’ is important for subsequent sleep, and that the effect of environmental factors and motivation are key factors to consider in sleep studies. According to Professor Vyazovskiy: “Arguably, the time spent awake and specific wake activities are determined, to a large extent, by environmental contingencies, both predictable and unpredictable. Therefore, changes in sleep habits, produced by our experimental manipulations, can arise primarily from an altered relationship between the organism and the environment. In this respect, our study makes a strong case that studying sleep in an ecological context can provide new insights, beyond those obtained in standard laboratory conditions.”

The full paper “Waking experience modulates sleep need in mice”, in collaboration with Professor David Bannerman from the Department of Experimental Psychology, is available to read in BMC Biology.

Similar stories

Improved Risk Estimation of Bipolar Spectrum Disorders in Adolescent Offspring of Bipolar Parents

This new study using Canadian and Swiss data showed that the risk calculator used to predict the likelihood of developing a major mood disorder was correct approximately 70% of the time. The study results suggest this may be a useful clinical tool in routine practice for improved individualised risk estimation of bipolar spectrum disorders among the adolescent offspring of a parent with a bipolar disorder.

New study on link between autoimmunity and pain

Patients with autoantibodies which target neuronal proteins can have pain as an under-recognised clinical manifestation.

Understanding the mechanisms involved in Alzheimer's disease

A new study from the Department of Pharmacology sheds light on the link between the two major Alzheimer's disease pathologies.

Continued ethical animal research needed to advance treatment of brain disease, researchers argue

More research is needed to improve the treatment of brain diseases such as depression, Alzheimer’s or ADHD. A widely held view within the scientific community is that this cannot be done without ethically conducted animal research.

Ground-breaking Treatment Offers New Hope for Patients with Persecutory Delusions

Feeling Safe is a new treatment programme for persecutory delusions, which promises a step change in the treatment of severe mental health problems.