Are you suffering sleep deprivation?

Have you ever been sleep deprived enough to cause a nuclear reactor meltdown, or a catastrophic oil spill costing over two billion dollars?

Biologically, quality sleep is a restorative, consolidated, and an uninterrupted process that cycles through multiple stages (Non-REM and REM) to repair cells, consolidate memories, and regulate hormones. It requires sufficient duration (usually 7+ hours), low wake-after-sleep-onset (few awakenings), and synchronisation with our circadian rhythms. [1]

Sleep Deprivation

Sleep deprivation can build up from trying to sleep during the day, which is out of sync with our circadian rhythm, disrupting our sleep cycles causing us to wake up more frequently.

According to sleep researchers, even a small shift between your internal clock and your actual sleep schedule creates a 'mental fog' similar to being mildly intoxicated. This is because both conditions impair cognitive function and reaction time, making it harder to concentrate, remember details, or make decisions. [2-3]

A study by Van Dongen et al. 2003 shows how people who are sleep-deprived may consider themselves to be ‘functioning well’ which can increase the risk of accidents as we are less able to censor our own behaviours [4]. Studies also show how a lack of sleep is not dissimilar to being intoxicated by alcohol and sleep deprivation may indeed have a greater negative impact than alcohol of driver reaction time and driving performance. [5-6]

Microsleeps

A further risk is that of ‘Microsleeps’, which are involuntary lapses in alertness lasting 1 to 15 seconds. When the circadian rhythm is disrupted, or due to high sleep debt, the brain can experience "sleep attacks" during periods when it should be awake. During these few seconds, the brain effectively shuts down its processing of external information, which can be catastrophic if it occurs while driving or operating machinery as they often happen unnoticed.   [7-8]

Brain Fog

This fragmentation of our sleep cycles, especially deep N3 stage sleep, reduces the brain’s ability in clearing out the toxins that build up from our mental activity causing ‘mental fog’ or fatigue. [9] 

When shift work takes us out of synch with our biorhythm this can significantly impact our brains ‘executive centre’ or ‘processing safety part’, the medial prefrontal cortex (mPFC). [6]

This region is responsible for critical safety-related functions, including impulse control, risk assessment, and logical reasoning.

Studies show how the role of the medial prefrontal cortex (mPFC) has a regulating authority of our emotional centre, the amygdala, from a ‘top-down’ authority, controlling our emotional responses. [10]

We can use our sense of tiredness as a ‘fatigue barometer’. 

The longer we are awake and cognitively active the more adenosine (the byproduct of energy consumption, ATP breakdown) builds up. Also, we can use this fatigue barometer as a measure of our ‘sleep dept’ as we need both the sleep opportunity and quality sleep, in synch with our biorhythm, to clear out these metabolic waste products from our brain through the glymphatic system. This is critical both to clean our brain and to re-energise regions of the brain with glucose and glycogen. 

The sense of ‘brain fog’ after sleep can show us how our sleep debt is still present. [11]

Fight or Flight

Sleep deprivation can weaken or even ‘uncouple’ our ‘emotional brake’, the mPFC, leading to the amygdala to strengthen its connection to the Locus Coeruleus (see diagram below). The locus coeruleus initiates our ‘fight or flight’ adrenergic centre (regulating our blood pressure, heart rate, respiration, metabolism, and arousal), leading us to feel more hypervigilant, and hypersensitive taking a more negative and reactive response to neutral events and increasing risk-taking behaviours. [11-12 -14]

Fatigue, circadian disruption, and sleep loss in shift workers can cause impaired cognition, slower reactions, poor decisions, safety rule violations, substance use (caffeine for alertness, alcohol for sleep), and more workplace accidents. [15] 

Accidents

Studies starting in the 1980’s have shown how sleep deprivation can be a major underlying factor in fatigued operators and managers in some of the world’s most catastrophic accidents [16] such as the Challenger space shuttle explosion and the Exxon Valdez oil spill.

Conclusion

In conclusion, although many professions rely on working through the night, the human body is not designed for sustained circadian disruption, and the consequences extend far beyond simple fatigue. Misaligned sleep leads to impaired cognition, emotional dysregulation, increased accident risk, and serious long-term health conditions, often made more dangerous by the brain’s ability to adapt to a false “new normal” of functioning. Recognising fatigue as a biological warning signal is essential, as is taking proactive steps - such as improving sleep quality, managing light exposure, using strategic napping, and seeking support for underlying sleep disorders. Ultimately, prioritising sleep is not a luxury but a critical foundation for health, safety, and optimal performance in a 24-hour society.

Cognitive Behaviour Therapy

Cognitive Behavioural Therapy for Insomnia (CBT-I) is widely recognised as the "gold standard" first-line treatment for chronic insomnia, as recommended by leading medical bodies such as the American College of Physicians. This structured, non-pharmacological therapy works by targeting and changing problematic behaviours and thoughts related to sleep. Notably, CBT-I has demonstrated a 70–80% success rate in improving sleep, according to clinical studies published by the American College of Physicians, which lends strong credibility to its effectiveness.

Make an Appointment

References:

[1] National Library of Medicine. 2023. Physiology of Sleep. https://www.ncbi.nlm.nih.gov/books/NBK482512/

[2] Scientific Reports. 2018. Daily circadian misalignment impairs human cognitive performance task-dependently. https://www.nature.com/articles/s41598-018-20707-4#:~:text=Abstract,they%20progressively%20hinder%20daily%20learning.

[3]. Science Direct. 2021. Sleep timing, chronotype and social jetlag: Impact on cognitive abilities and psychiatric disorders. https://shorturl.at/HtCVG

[4] The National Library of Medicine. 2003. The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. https://pubmed.ncbi.nlm.nih.gov/12683469/

[5] Pub Med. 2000. Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. https://www.researchgate.net/publication/12338629_Moderate_sleep_deprivation_produces_impairment_in_cognitive_and_motor_performance_equivalent_to_legally_prescribed_levels_of_alcohol_intoxication

[6] National Library of Medicine. 2020. The impact of sleep deprivation and alcohol on driving: a comparative study. https://pubmed.ncbi.nlm.nih.gov/32571274/

[7] Rise. 2023. Falling Asleep Randomly: It’s Not Always Narcolepsy. https://www.risescience.com/blog/falling-asleep-randomly

[8]. Science and Technology. 2023. Microsleep. The unseen menace of sleep deprivation. https://www.meer.com/en/75337-microsleep#:~:text=Understandably%2C%20microsleep%20can%20pose%20significant%20risks.%20During,lead%20to%20accidents%2C%20injury%2C%20or%20even%20death

[9] Science Direct. 2025. Neurotransmitter modulation of sleep-wake States: From molecular mechanisms to therapeutic potential. https://www.sciencedirect.com/science/article/abs/pii/S1389945725002163#:~:text=Since%20the%20last%20century%2C%20we%20have%20made,in%20developing%20effective%20drugs%20and%20treatment%20methods.

[10] Neuro Sciences. 2023. The consequences of sleep deprivation on cognitive performance. https://nsj.org.sa/content/28/2/91

[11] NIH. 2025. Brain Basics: Understanding Sleep. https://www.ninds.nih.gov/health-information/public-education/brain-basics/brain-basics-understanding-sleep#:~:text=Quality%20sleep%E2%80%94and%20getting%20enough,in%20the%20brain%20during%20sleep.

[12] National Library of Medicine. 2025. The Role of Sleep and the Effects of Sleep Loss on Cognitive, Affective, and Behavioural Processes. https://pmc.ncbi.nlm.nih.gov/articles/PMC12168795/#:~:text=Adequate%20sleep%20supports%20sustained%20vigilance,emotional%20regulation%2C%20and%20daytime%20performance

[13] Science Direct. 2007. The human emotional brain without sleep — a prefrontal amygdala disconnect. https://www.sciencedirect.com/science/article/pii/S0960982207017836#:~:text=Group%20level%20differences%20in%20amygdala,thus%20govern%20appropriate%20behavioral%20repertoires.

[14] PubMed Central. 2020. The role of the locus coeruleus in the generation of pathological anxiety. https://pmc.ncbi.nlm.nih.gov/articles/PMC7479871/#:~:text=The%20locus%20coeruleus%20(LC)%20is%20a%20neural,is%20associated%20with%20hypoarousal%20and%20attention%20deficits.

[15] Oxford Academic, Sleep. 2022. Sleep Time and Risk Taking Behaviour in Night Shift-Workers. https://academic.oup.com/sleep/article/45/Supplement_1/A151/6592464

[16] Hercleon. 2024. The 5 biggest disasters caused by sleep deprivation. https://hercleon.com/blogs/herctalk/the-5-biggest-disasters-caused-by-sleep-deprivation