Society plays an enormous role in shaping our attitudes towards sleep and this affects how much sleep we get. Sleep, in turn, has a major impact upon society, influencing childhood learning and development, affecting workplace safety and efficiency, and even risk-taking behaviour.

Sleepiness and sleep disorders cost the economy billions of pounds each year in days off work, lost time, inefficiency and accidents, yet the machismo associated with short sleep and long work hours is pervasive. Society glorifies "driven" individuals who succeed on apparently little sleep, whereas those who prioritise sleep are viewed as weak and not having the "right stuff". Some professions even demand excessive sleep deprivation as part of the job or a "rite of passage".

In addition to work, many other factors affect our sleep, including children, pets, noise pollution, temperature, bed type, pain, gender, bed partner, your income, hobbies, alcohol, drugs and medications, exercise, television, radio, computers, telephones – the list goes on and on. Some of these factors can be relatively simple to deal with on an individual level, for example using earplugs, wearing bed-socks, taking the TV, radio, computer, telephone and pets out of the bedroom, drinking less alcohol, exercising earlier, and going to bed earlier. However, some things are impossible to change, such as our genes and sunrise.

Are you a lark or an owl?

If you are alert in the mornings and go to bed early you are a "lark", but if you hate mornings and want to stay awake through the night, then you are an "owl". These terms have been used to describe the phenomenon of diurnal preference: whether you are a morning-type or an evening-type person, based on the times when you prefer to sleep and when you do your best work.

While you might think that this is a personal choice, diurnal preference is partly encoded in our genes. If a group of people are kept on the same light-dark schedule (16 hours light, 8 hours dark) for several weeks, some people will go to bed and wake early, some will go to sleep late and lie-in, some will sleep for only 7 hours, some for 9 hours and so on. Each person will find their own natural timing within the day - their chronotype.

Across a population, there are a range of chronotypes due to individual differences. A number of key genes have been identified which are associated with sleep timing and sleep duration and these genetic factors help to determine whether we are naturally short sleepers, or long sleepers, or prefer to wake early or go to bed late. These differences are remarkably consistent despite all the societal factors in the real world.

Sunrise and sunset

An important consideration in sleep regulation is the role of light, which affects both the body clock and levels of alertness during the day. The body clock (circadian clock) located within the suprachiasmatic nuclei in the brain generates a rhythm that is near to, but not exactly, 24 hours. In humans the body clock is a little longer than 24 hours – around 24 hours and 20 minutes – and in order to make sure that our circadian rhythms are timed appropriately with the real world, environmental time cues must reset this internal clock every day.

Under normal circumstances, exposure to the 24-hour pattern of sunrise and sunset synchronises (entrains) biological rhythms to environmental rhythms. Failure to receive this light-dark information, as experienced by blind individuals, means that the body clock will drift through time.

Light is the critical re-setting agent that allows us to recover from jet lag. Exposure to the light/dark cycle in the new time zone resets our body clock. But light also plays another role in sleep: it can acutely enhance alertness and performance during both the day and the night. Brain imaging studies have found that light increases activity in many of the brain areas involved in alertness, cognition and memory (thalamus, hippocampus, brainstem) and mood (amygdala). So, inappropriately timed light exposure can disrupt not only sleep and circadian timing but also levels of alertness, performance and mood.

How society, genes and light all interact to generate individual sleep patterns is clearly complicated. As a result we might expect to see differences across societies and between different countries.

Do Britons and Germans, for example, get up and go to bed at the same time and do we sleep for about the same length of time? If our sleep patterns differ, what could be the basis for these differences? What is the most important driver for how long we sleep and when we sleep: is it our social structure, our genes or the environment? And what happens when we don't get enough sleep?

These are some of the questions the Professor Till Roenneberg of the University of Munich and I want to think about and start to answer at our presentation on sleep at the Cheltenham Science Festival on Tuesday 12 June.

Associated with this discussion will be the generation of new data about sleep patterns in Germany and the UK using a short online sleep survey, the Munich Chronotype Questionnaire. We need as many participants as possible from the UK. So far we have only around 1,000 Brits have completed the survey, compared with more than 65,000 Germans.

Some of the findings emerging from the German study are fascinating:

• The further west you live within Germany the more likely it is that you will get up later.

• The further north you live within Germany the more likely it is that you will get up later.

• The larger the population of the city where you live, the more likely it is that you will get up later.

When you have completed the questionnaire, an automatic evaluation of your chronotype (your personal sleep profile) will be sent to you via email. You will see how your results compare with others who have completed the questionnaire so far. You can then start to think about some of the factors that regulate your sleep pattern. Is it the result of your lifestyle and the demands of your work, your genes or your environment?

Will the Brits and the Germans differ in their sleep patterns? Help us answer this question by completing the questionnaire!

Professor Russell Foster is head of the Nuffield Laboratory of Ophthalmology and a Fellow of Brasenose College, University of Oxford. He is chair of Cheltenham Science Festival, 12–17 June 2012