Sleep is a reversible and naturally reoccurring state on inactivity that is characterized by a loss of consciousness and decreased sensitivity to external stimuli. Sleep is driven by circadian rhythms, or one’s internal clock that cycles between sleepiness and wakefulness at a 24-hour interval. These rhythms respond to light and dark patterns in an organism’s environment, which is why we sleep at night. Despite the notion that sleep is inactive, the brain is very active during sleep. Sleep occurs in cycles that consist of stages 1-4 of non-rapid eye movement sleep, and REM, or rapid eye movement sleep. Stages 1 and 2 are considered light sleep, whereas stages 3 and 4 are a state of deep sleep, where the arousal threshold is high; this means that it is difficult to wake someone up from stages 3 and 4 sleep. More importantly, these stages of deep sleep are restorative sleep. In these stages, the body repairs its tissues, stimulates growth and development, boosts immune function, and restores energy. REM sleep is characterized by “muscle atonia” or muscle paralysis, as well as vivid dreams. REM sleep is crucial for memory consolidation, which is why children spend more time in this stage than adults do.

Sleep, and more specifically sleep deprivation, is a major issue amongst college students and America’s general population. Americans associate sleep with unproductivity, but humans actually require copious amounts of sleep. Lack of sleep affects people’s physical and cognitive function, reaction times, motivation, and their ability to make rational decisions. According to scientific studies, sleep deprivation causes a huge decrease in attention span and working memory. The brain’s prefrontal cortex, the region involved in complex cognitive behaviors, planning, and decision making, is much more active in a rested individual than in a sleep deprived one. Sleep deprivation also negatively impacts spatial attention, decreasing one’s ability to make saccadic, or very rapid, eye movements. Because of this, driving while sleep deprived poses danger to not only oneself, but to others on the road.  

One controversial issue in America is the start time to many schools. The CDC, as well as several other health organizations recommend that schools start no earlier than 8:30 a.m. This is because teens possess different circadian rhythms from children and adults. Adolescents tend to stay up later at night, and sleep in later in the day, driven by the difference in the way their brains respond to light. After puberty, adolescents require more sleep than any other age group, ideally 9 hours per night. Starting schools at a later time will improve cognitive performance amongst teenagers, as well as overall grades.  

New technology habits are making this issue much worse. Many teens, and even adults are participating in activities that involve screens at night. This is problematic because the blue light emitted by phones, tablets, and televisions is suppressing the body’s secretion of the hormone melatonin, which signal’s the body when it’s time for sleep. By using screens at night, the brain thinks it is still daytime, delaying bodily cues for sleep. Another factor that affects melatonin secretion, as well as the secretion of human growth hormone, is the use of alcohol before bedtime. Alcohol use is very prevalent amongst college students, and it is important to note that alcohol affects both bodily hormones, and the brain’s neurotransmitters, thereby decreasing one’s quality of sleep.

Throughout this podcast, I will discuss sleep and its scientific mechanisms, as well as the issue of sleep deprivation in college students and Americans as a whole. Sleeping too much or too little can put one at risk for heart disease, depression, obesity, and several other health issues.  I also may address different sleep disorders that are prevalent amongst the population such as insomnia, and how it affects cognitive performance.
