Sleep

In the third decade of the 21st century, #sleep is still a ‘black box’. It’s not as dark in there as it used to be, and advances have been made to light up certain corners of what seems to be a really important and not-so-little box. Sleep is a vital physiological process that contributes to overall #health and #cognitivefunction. However, #sleepdeprivation is a common problem that can adversely affect #cognitiveperformance, including #attention, #focus, #concentration, #memory, and #learning (Leibniz Research Center for Working Environment and Human Factors, n.d.). We will take a brief look at the #neuroimmune and #neuroendocrine overlaps in #sleep and #cognition using a #systemsbiology approach, highlighting the interweaving roles of #circadianrhythm, #stressresponse, and #inflammation in #cognitiveperformance.

The average sleep duration varies significantly among #mammals, ranging from just a few hours to more than 20 hours per day (Zepelin, Siegel, & Tobler, 2005). For example, giraffes typically sleep for only 1.9 hours per day, while brown bats sleep for approximately 19.9 hours daily (Zepelin et al., 2005). In humans, the recommended amount of sleep is between 7 and 9 hours per night for adults, while infants and children require more sleep to support their growth and development (Hirshkowitz et al., 2015).

The variation in sleep duration across different mammalian species can be attributed to several factors, including ecological pressures, energy conservation, and predation risk (Zepelin et al., 2005). For instance, herbivorous prey animals, such as horses and cows, tend to sleep less to remain vigilant for predators, while predators like lions and tigers sleep more due to their lower predation risk and energy-intensive hunting activities (Capellini, Barton, McNamara, Preston, & Nunn, 2008). Moreover, sleep duration in mammals has also been associated with brain size and metabolic rate, with smaller animals exhibiting higher metabolic rates and shorter sleep durations (Capellini et al., 2008).

In #humans, sleep serves several essential functions, including the regulation of #metabolicprocesses, the consolidation of memory and learning, and the maintenance of immune system function (Besedovsky, Lange, & Born, 2012; Walker, 2009). Sleep deprivation, on the other hand, can lead to a host of negative health outcomes, such as impaired cognitive performance, increased susceptibility to infections, and a higher risk of chronic conditions like #obesity, #diabetes, and #cardiovasculardisease (Banks & Dinges, 2007; Irwin, 2015).

One of the critical features of sleep in humans and other mammals is the sleep cycle, which consists of distinct stages, including rapid eye movement (#REM) sleep and non-REM sleep (Zisapel, 2018). During REM sleep, the brain is highly active, and most dreaming occurs, while non-REM sleep is characterized by deep, restorative sleep (Zisapel, 2018). The progression through these sleep stages is crucial for optimal cognitive and physiological functioning.

So, sleep is of paramount importance for the overall health and well-being of mammals, including humans. The variation in sleep duration among different mammalian species can be attributed to several factors, such as ecological pressures and metabolic rates. In humans, sleep serves numerous essential functions, including cognitive performance, immune function, and metabolic regulation. Therefore, understanding the underlying mechanisms and factors that govern sleep duration and quality is crucial for developing strategies to promote optimal health and well-being, let alone what happens when we just don’t sleep enough. What are the processes that we know happen, what systems talk to each other, how do they interconnect, and how does all that impact general wellness and health in general and cognitive functioning in particular?

If anyone would like to go deeper down this rabbit hole with me, say so in the comments.

The #circadianrhythm is an endogenous 24-hour cycle that governs various #physiologicalprocesses, including #metabolicprocesses, #fertility, and the stress response (Refinetti, 2016). It plays a crucial role in the regulation of #metabolichormones such as #insulin, #ghrelin, and #leptin, which influence #glucosemetabolism and #energybalance (Turek et al., 2005). The circadian rhythm also influences fertility through the timing of #reproductivehormone secretion, such as #luteinizinghormone (Boden et al., 2010). Furthermore, the circadian rhythm regulates #cortisol secretion, which modulates cognitive processes and contributes to the stress response (Dickmeis, 2009).

Sleep Deprivation

Sleep deprivation can have a profound impact on cognitive performance. Research has shown that lack of sleep not only alters brain activation but also affects the connections between neurons, which have a significant effect on #memoryperformance and #workingmemory (Leibniz Research Center for Working Environment and Human Factors, n.d.). Impaired #neuroplasticity due to sleep deprivation can result in difficulties in processing new external stimuli and information, leading to diminished learning abilities (Leibniz Research Center for Working Environment and Human Factors, n.d.). The stress response is also linked to cognitive function, with chronic stress leading to impaired cognitive processes (McEwen & Sapolsky, 1995). Cortisol, a hormone released during the stress response, can modulate cognitive function, affecting #memoryconsolidation and #memoryretrieval (Wolf, 2009).

The #immunesystem and #endocrinesystem play essential roles in #sleep and #cognition in other broad ways. Sleep is crucial for immune function, with the sleep-wake cycle regulating #cytokine production, such as interleukin-6 and tumor necrosis factor-alpha, which modulate immune responses (Besedovsky et al., 2012). Additionally, there is a complex interplay between the endocrine system and cognitive performance, with hormones such as cortisol and #melatonin influencing cognitive processes (Maquet, 2001).

Inflammation

#Inflammation and #proinflammatory #cytokines are also intricately involved in circadian rhythm regulation, stress response, fertility, and metabolism. Proinflammatory cytokines can impact #clockgene expression, with implications for sleep disturbances (Cavadini et al., 2007). Furthermore, proinflammatory cytokines can affect the hypothalamic-pituitary-adrenal (#HPA) axis, which plays a crucial role in the stress response and cognitive function (Miller et al., 2009). Inflammation can also impact fertility and metabolism, with proinflammatory cytokines such as interleukin-1β and tumor necrosis factor-alpha influencing reproductive function and metabolic regulation (Fernández-Real et al., 2001).

Understanding the interweaving systems involved in sleep and cognitive function is essential for developing targeted interventions to improve cognitive performance. A #systems #biology approach can potentially identify patient-specific factors contributing to the understanding of the role that circadian rhythm and sleep deprivation play in attention, focus, concentration, memory, and learning problems. By examining the complex interactions between the nervous, immune, and endocrine systems in the context of sleep deprivation and cognitive functioning, researchers and clinicians can develop a more comprehensive understanding of the mechanisms underlying cognitive impairments and devise personalized treatment strategies.

Nutrition & Exercise

Beyond sleep deprivation and circadian rhythm, the systems biology approach could also be used to investigate the complex interactions between other factors that influence cognitive performance, such as nutrition, exercise, stress, and environmental factors. By considering the interrelated roles of the nervous, immune, and endocrine systems in the context of these factors, researchers and clinicians can develop a more comprehensive understanding of the determinants of cognitive health and well-being. For example, the role of nutrition in cognitive performance has been increasingly recognized as an important area of investigation. A systems biology approach could be employed to examine the complex relationships between dietary factors, the gut microbiome, and cognitive function. This research could help identify specific dietary patterns or nutrients that promote optimal cognitive performance and develop personalized nutrition recommendations for individuals based on their unique genetic and metabolic profiles.

Similarly, the effects of physical activity on cognitive performance and overall mental health have been well-documented, but the underlying mechanisms through which exercise exerts its beneficial effects on cognition remain to be further understood —recent research seems promising. By applying a systems biology approach to the study of exercise and cognitive function, researchers could gain a deeper understanding of the molecular and cellular pathways that mediate the beneficial effects of exercise on brain health and cognitive performance.

As the field of systems biology continues to evolve, further research is needed to explore the intricate relationships among circadian rhythm, sleep deprivation, #neuroimmune and #neuroendocrine systems, and cognitive performance. By investigating these interrelated processes, it is possible to identify novel #biomarkers and therapeutic targets that could inform the development of more effective interventions for individuals struggling with cognitive impairments due to sleep deprivation or other related factors. Furthermore, the use of advanced technologies, such as #neuroimaging, #genomics, #proteomics, and #computationalmodeling in #computationalbiology, will help to unravel the #complexnetworks and #pathways involved in sleep and cognition, paving the way for novel therapeutic strategies and personalized medicine approaches.

Moreover, recognizing the potential of #precisionmedicine approaches in #neurology and #psychiatry could provide screening solutions, deploy time-sensitive #detection and diagnosis, and tailor treatment strategies to an individual's specific clinical, genetic, and biological characteristics and risk factors (Sabbagh et al., 2021). In addition to improving our understanding of sleep and cognition, the systems biology approach can also be applied to other areas of neurology and psychiatry, such as #neurodegenerativediseases, #mooddisorders, and #addiction. By considering the interconnected roles of the nervous, immune, and endocrine systems in these conditions, researchers and clinicians can develop a more comprehensive understanding of the underlying #pathophysiology and the aforementioned potential for identifying novel therapeutic targets. This personalized approach to treatment holds promise for addressing the growing burden of #neurologicaldiseases and #psychiatricdiseases on healthcare systems and societies worldwide. By leveraging these advances in genomics, proteomics, and other omics technologies, it may be possible to identify specific genetic, epigenetic, or #metabolic signatures that are indicative of increased risk for sleep-related cognitive impairments. Such biomarkers could be used to further inform the development of personalized prevention and intervention strategies for individuals at risk.

Sleep Deprivation is a significant #publichealth burden, as most -if not all- of the pathways highlighted here can be easily linked to accidents (including gun violence, road rage, and increased hostility), degenerative disorders of various parts of the body and brain, metabolic disorders further contributing to heart disease, stroke and the list goes on.

Another area of interest is the potential for leveraging digital health technologies, such as wearable devices and mobile health applications, to monitor and improve sleep quality and cognitive performance. These technologies could provide real-time, personalized feedback to individuals about their sleep patterns, circadian rhythm, and cognitive function, enabling them to make informed decisions about their lifestyle and health behaviors to optimize cognitive performance and overall well-being.

A systems biology approach to understanding the #neuroimmune and #neuroendocrine overlaps in sleep and cognition offers a promising avenue for advancing our knowledge of the complex interactions between #circadianrhythm, sleep deprivation, and #cognitiveperformance. This interdisciplinary approach has the potential to revolutionize our understanding of the determinants of cognitive performance. By considering the interconnected roles of the nervous, immune, and endocrine systems in the context of sleep and cognition, researchers and clinicians can better identify #patientspecificfactors and develop #targetedinterventions to improve cognitive function and overall #qualityoflife.

References:

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Desiderio Pina, MD, MPH

TheMindAndBodyDoc-Physician/Neuroscientist — @mindandbodydoc

I provide compassionate care for children (5 years & older), adolescents, adults & families struggling with nutritional, drug, & neuropsychiatric problems.

I’ve had the privilege to teach at various medical schools (MD & DO), and residency programs (Psychiatry, Family Practice, and universities, and have done clinical and basic science research in the past. I’m currently on staff at a few hospitals and mostly care for patients via telemedicine.

I generally talk & write about things that catch my fancy in the news and from the recent medical literature.

Including but not limited to: #wellness, #neurosciences, #neuropsychiatry #culturalpsychiatry #ethnobotony #mycology #mycologicalmedicine #digitalhealthcare, #healthcaremanagement, and #psychoneuroendocrineimmunology