Blog

Updated July 31st 2024

Recently I have been experiencing something great; energy that lasts all day long without any daytime slumps!

What is the difference? A combination of good nutrition, exercise a few times per week and sleep.

However, I had the experience recently of feeling like I couldn’t string a full sentence together, to the point where I had to put an end to a phone conversation half way through. And all because, I hadn’t slept due to a lovely bout of food poisoning.

As we saw in recent blogs, courtesy of Oliver Sifkovits, focusing on what we eat can make all the difference to how we perform. Sleep is another physiological lever that can contribute to, and detract from how we perform.

There is a compelling body of evidence that ties our performance, be it professional or personal, to adequate levels of sleep. Chronic sleep loss negatively affects focus, memory and cognition, impacting productivity and relationships, and overall well-being.

Not getting the correct amount of sleep is linked to heart disease, obesity, diabetes, high blood pressure, depression, and psychosis. It also causes unethical behavior (see Shane O’Mara).

How many times have you taken dodgy short-cuts when you are tired? The brain of the sleep-deprived person has to work harder than that of non-sleep-deprived person to accomplish any given task. Imagine what information your brain is excluding paying attention to when it is tired and the decisions it is having you make?!

Research shows that young adults (under 30 years) perform poorer than their older counterparts (50-60 years) following periods of sleep deprivation – whilst at the same time more confidently and inaccurately overestimating their abilities. Where does this show up in organisations and decisions being made?

Furthermore, we are less adept at reading social cues and responding appropriately inter-personally when affected by sleep loss. Our ability to accurately detect emotions tied to threat (angry faces) and reward (happy faces), becomes blunted, when sleep deprived. Also, sleep-deprived people fail to recall pleasant memories, yet recall gloomy memories just fine, and so sleep affects our positivity and happiness.

Additionally, recent neuro-scientific research points to the role of sleep in memory consolidation. Studies have shown that hippocampal neurons activated during learning tasks are reactivated during slow wave sleep, reinforcing the neural network and consolidating the learning. In a study requiring participants to learn routes through unfamiliar streets, performance, as measured by error rates in the task, was significantly lower for those who had benefited from sleep. Other studies focusing on sleep loss provide clear evidence for lower academic performance caused by reductions in both declarative and procedural memory, suggesting that the prefrontal cortex is highly sensitive to sleep deprivation. So, regular good quality sleep is a precursor for memory and learning.

Studies of sleep distinguish between acute sleep deprivation, defined as short bouts (24- 72 hours) of complete sleep loss, and chronic partial sleep restriction, defined as continued periods of less than normal quantity of sleep (for example 3-5 hours sleep when the individual’s ‘normal’ pattern is 7-8 hours). Performance in cognitive tasks shows a consistent deterioration in both acute and chronic forms of sleep deprivation. However recovery from chronic partial sleep loss is slower.

According to renowned sleep researcher Daniel Kripke, consistently getting between 6.5 and 7.5 hours of sleep per night not only contributes to longevity but also enhances happiness and productivity. Deviating from this optimal range can lead to various unnoticed issues, affecting our overall well-being. It is imperative that we pay closer attention to our sleep habits and consider whether they are supporting or hindering our learning, habit formation, and overall performance and happiness.