Category Archives: Politics

Can sleep loss induce a negative implicit bias towards Arab-Muslim names?


People suck. Well they certainly seem to after several nights without sleep. As the lost hours pile up, those simple things sent to try us become all the more difficult to face. We are generally just less able to employ self-control to moderate our feelings towards the outside world. I mean, it’s like Nigel Farage said to me down the pub once, we even tend to make racist comments when we’re a bit tired. Now sleep deprivation does not make you racist, despite amusing attempts to throw old Nige a bone, but it may be that a lack of shut-eye can make us less able to inhibit unconscious biases.

Unconscious biases are not necessarily a bad thing before we start to bash them. They allow us to employ speedy decision making without having to weigh up the pros and cons of a situation. When you’re faced with immediate danger you don’t want to spend time considering the difficult childhood of your knife wielding assailant for any more than a split second before you run away with your tail, and wallet, trailing behind. However, when we’re not facing a troubled mugger your conscious mind can step in and make use of available mental resources to stop yourself acting on your unconscious biases. This allows you to mask your own biases under the shield of social desirability. However, how do you assess an individual’s unconscious biases if they are unaware of them themselves?

It is possible to assess your unconscious biases by completing something called the implicit association test (IAT). This was developed by social psychologists Anthony Greenwald who wanted to try to understand the unconscious biases individuals held. They felt that explicitly asking individuals about sensitive issues was a poor way to investigate controversial topics as people would be likely to hide their true responses behind a ‘socially desirable mask’. Instead if you got people to respond very quickly to words paired with negative or positive emotions you could see how readily certain associations are recognised. For example, you could show pictures of white and black faces and pair them with positive and negative emotions. You could then present every possible combination in a randomised order (black-good, white-bad; black-bad, white-good) and see how quickly people respond to these pairings. The logic being that if you were quicker to respond to black-bad and white-good than the other pairings you, on an unconscious level, see these as more strongly related than the alternatives. Race is used here as an example but this task has been used for a wide range of different judgements such as gender and careers, weight, age and many others. You can see many of them and give the task a go here.

It should come as no surprise that sleep is considered important when it comes to our unconscious biases. Hopefully anyone who has read at least one of these posts should be aware of how many things sleep is important for. A study published in 2015 showed that by stimulating slow wave sleep (i.e. the deepest stage of our nightly slumber) you could enhance daytime training to reduce unconscious negative biases. However, it was still relatively unknown how sleep loss could influence our own hidden biases. This is not just an interesting question but an important one too when you consider that implicit biases can negatively guide our behaviour outside of our awareness.

Therefore, in a paper published last month a team from Harvard University explored this question and wanted to understand whether chronic sleep deprivation could lead to an ‘unmasking’ of negative implicit biases. More specifically, they asked: Are we more likely to express an implicit negative bias towards Muslim Arab names when we are sleep deprived?

To test this question, seventeen participants were invited into the laboratory for 25 days and it was under these strictly controlled walls that participants’ sleep was monitored. During this period, invited participants spent five days on 4 hours sleep and two days on 8 hours. This continued for a total of three weeks. The same participants, were invited back 2 months later to spend another three weeks in the laboratory but this time they could sleep for 8 hours every night. This meant that each participant served as their own control for the study. On the 21st day participants were given the implicit association test (IAT) for Muslim-Arab names and the scores during the well-rested and sleep-deprivation conditions were compared. The researchers predicted that during sleep deprivation participants would show an increased negative implicit bias towards Muslim-Arab names (i.e. they would be less able to mask their biases).

So, what did they find?

Well when participants were well-rested they did not show a negative implicit bias towards Muslim-Arab names. This is good and somewhat encouraging. However, when they were sleep deprived the same participants did show significant evidence of a negative implicit bias. That is, they more readily associated Muslim-Arab names with “bad” rather than “good”. This suggests that sleep deprivation may make us more likely to express our implicit biases.

Well before we get carried away this task is not a perfect way to assess unconscious biases and simply because our perceptions are unconsciously altered does not mean our behaviour is too. It’s also important to note that this group of participants did not have an implicit negative bias normally (e.g. when well-rested). Yet, it was possible to see that a moderate bias was found following three weeks of substantial sleep deprivation. On that note, it would be very interesting to see if in groups who already have an implicit bias show the same increase in bias following sleep deprivation and whether good sleep could reduce the negative implicit bias shown.

However, it does suggest that sleep deprivation in situations where workers have to act quickly and intuitively may bias our perceptions in a negative, and potentially fatal, way. This is particularly relevant for police officers, military personnel, and individuals working in airport security who may work long shifts and who may need to make snap judgements. We should be careful before anyone shouts from the rooftops “being sleepy makes you more racist”. This task is looking at implicit biases and the IAT do not represent explicit biases. In most instances we have the time, and resources, to make a balanced judgement. Nonetheless this research showed that a lack of sleep can negatively influence our own unconscious biases towards others. As for outright racism? A lack of sleep won’t suddenly make you racist – sorry Nige.

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Alkozei, A., Killgore, W. D., Smith, R., Dailey, N. S., Bajaj, S., & Haack, M. (2017). Chronic Sleep Restriction Increases Negative Implicit Attitudes Toward Arab Muslims. Scientific Reports7.

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Filed under Politics, Psychology, Racism, Sleep Science

Have you considered sleep with that? How global warming may stop us getting a good night’s sleep

Insomnia and Heat

When we think about increasing global temperatures we tend to think melting ice caps, flooding, and conspiracy theorists who believe scientists (or the Chinese) make this stuff up to exert some unknown power and influence. However, the temperature at night has a direct influence on the quality of our sleep too. So, I’m back to talking about sleep again (the sigh of relief from my adoring crowd is audible – thank you). A recent paper, published in Science, has shown that global warming will not just have an effect on political alliances but also on our sleep. Trump, take note.

The premise of the recent paper, by Dr Nick Obradovich and colleagues, is a simple but profound one. As the summer months trundle on by (and yes, we get some occasional sunshine here in the UK too) you are probably acutely aware of the nightly sojourn to bed and futile attempts at sleep in the oppressive heat. Unless you have the advantage of a trusty fan or even a hint of a breeze outside you know you are going to toss, turn, and throw the covers around until you eventually nod off for a few fragmented hours. Temperature has an evident ability on our ability to get to sleep. This is shown clearly when we consider the changes in body temperature throughout a typical night. As we drift off our body temperature reduces and remains lowered during the sleep period until we wake up. At this point, it starts to rise again helping to improve alertness during the day. This pattern, or circadian rhythm, is no accident – it helps to send us off to sleep. This rise and fall is important and if we increase our temperature too much (e.g. lying in a particularly stuffy room) then we delay the time at which we drop off and are more likely to wake up during the night.

It is this quirk that a research group explored in relation to global warming. In light of what we know, will the increase in global temperature negatively influence our sleep? We can assess this by looking at unseasonably hot days during a month and correlate this with the reported number of nights of poor sleep in the population. This is exactly what Obradovich and colleagues did. They assessed the temperature changes from the average in a number of cities across the US and identified the sleep habits of hundreds of thousands of respondents to a large survey assessing health and disease. They controlled for potential confounders and found that as the temperature increased from the average, for any given month, that there was an increase in reports of nights with disturbed sleep. In fact, as the temperature rises then so does the number of disturbed nights of sleep. When the group compared low and high earners and young and old populations they found that those who were poorer and older tended to suffer more from the effects of temperatures spikes. Finally, as would be expected, they found that these effects were only significant when they looked at the summer months.

This highlighted largely what we already know: that temperature negatively impacts on sleep quality by interfering with the normal process of drifting to sleep. However, the interesting point comes from the next finding of their study. They identified the predicted increases in global temperature until the end of the century from NASA. They then plugged in these values from the first part of the study to identify the effect of increasing temperatures of the number of nights sleep loss until the end of the century. Somewhat worryingly, they found that over the next century the number of nights poor sleep increases in line with the increases in temperature in part due to global warming and climate change. This has implication for physical and mental health which has consistently been tied to the quality and duration of our sleep.

It is important to note that there are plenty of caveats to this study. For example, its indirect and correlational measure of sleep and temperature should raise some concerns about the validity of the findings. Furthermore, it’s important to note that sleep was assessed with a single self-report question, “During the past 30 days, for about how many days have you felt you did not get enough rest or sleep?”. As the authors suggest, further experimental data is needed to back up their claims.  However, the findings from this study do fall in line with what we already know about the effect of temperature on sleep. It is not a stretch to claim that global warming, ignoring other external factors, will have a negative impact on our sleep. There are of course ways to mitigate the negative effects of increasing global temperature but this study also accounted for that. The poorest and oldest stand to suffer most as they cannot afford to keep air conditioning running all night. Therefore, although this is one admittedly large-scale study there is still additional research which needs to further understand the true impact our warming climate will have on our sleep and subsequent health. For the time being, it raises an important reminder that the effects of global warming are far reaching and ignoring the clear evidence for its existent is nothing short of irresponsible and short-sighted. Again, take note Mr. President.

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Obradovich, N., Migliorini, R., Mednick, S. C., & Fowler, J. H. (2017). Nighttime temperature and human sleep loss in a changing climate. Science Advances, 3(5), e1601555.

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Filed under Media, Politics, Psychology, Sleep Science, Work and Society