Sleep is a fundamental physiological process that plays a crucial role in maintaining our overall health and well-being. While the importance of sleep is well-known, the chemistry behind this restorative phenomenon remains a subject of ongoing research.
Did you know?
According to a study published in 2008 by Murzyn, people who had access to black and white media are likely to experience dreaming without colors as opposed to those with with no exposure to such.
Neurotransmitters involved in sleep regulation
So, you know that feeling when you’ve been up for hours and start to feel that irresistible urge to just doze off? That’s thanks to a little molecule our brain produces. As we stay awake, adenosine levels gradually build up, nudging us closer to sleepiness.
Let’s not forget about melatonin, the sleep hormone. It’s like our internal clock manager, making sure we feel sleepy when it’s time to hit the hay.
Then there’s our buddy GABA (Gamma-Aminobutyric Acid). It’s like the ultimate chill pill for our brain. It steps in to quiet down the buzzing activity, ease anxiety, and set the stage for relaxation, making it easier to drift off into dreamland.
Cortisol got a rhythm of its own, peaking in the morning to kickstart our day and gradually winding down as evening approaches. This hormone keeps our wake-sleep cycle in check, helping us stay alert during the day, and wind down for a good night’s rest.
Now, here comes the unsung hero of sleep: growth hormone. It doesn’t just help us grow during childhood, it’s also hard at work during deep sleep, repairing tissues, promoting muscle growth, and giving us that rejuvenating snooze.
There’s this duo of leptin and ghrelin. These hormones are all about keeping our appetite in check, but they also have a say in our sleep patterns. When they’re out of whack, it can lead to restless nights and insomnia.
Two Main Stages of Sleep
- Non-Rapid Eye Movement (NREM) Sleep: NREM sleep is characterized by slow wave activity, facilitating physical restoration, memory consolidation, and hormone regulation.
- Rapid Eye Movement (REM) Sleep: REM sleep is marked by vivid dreaming and increased brain activity, resembling wakefulness.
The transition between NREM and REM stages is orchestrated by a delicate interplay of neurotransmitters and hormones. This process ensures the seamless progression through essential stages of restorative sleep.
The Chemistry of Caffeine
Caffeine is a psychoactive substance that stands out for its widespread consumption and its impact on the body’s chemistry. Its function to stimulate the central nervous system is attributed to its ability to block adenosine receptors in the brain.
Just how much is too much caffeine?
According to the US Food and Drug Administration (FDA), the recommended consumption for healthy adults is about 400 milligrams per day. This is approximately equal to four cups of brewed coffee or ten cans of cola.
Sleep Disorders
Various sleep disorders can arise from imbalances in the chemistry of sleep.
- Insomnia – characterized by difficulty falling or staying asleep, often involves dysregulation of GABA and adenosine.
- Sleep Apnea – a condition marked by interrupted breathing during sleep, has been linked to imbalances in neurotransmitters such as serotonin and norepinephrine.
- Narcolepsy – is a neurological disorder causing excessive daytime sleepiness, associated with abnormalities in the production of a neuropeptide involved in wakefulness regulation called hypocretin/orexin.