By Erin Cassidy-Eagle PhD | June 20, 2014
Previous Director of Research, ETR
I love sleep. Not just sleeping, but the science of it all. This is why some of my friends and colleagues call me “The Sleep Geek.” It’s a badge I wear proudly.
My research looks at the effects of sleep on older people. Evidence suggests that poor sleep can contribute to, or perhaps accelerate, memory loss and cognitive decline in older populations. We’re involved in a study exploring whether sleep therapy—helping people learn how to achieve better sleep—might improve outcomes in memory and cognition over time.
In adults, short sleep is linked to a wide range of problems, including obesity, hypertension, and mental health issues such as anxiety, depression and suicidality. Sleep affects day-to-day choices and behaviors, too. If you stay up all night, you’ll probably make riskier decisions at the casino. You’ll also be ordering up some delicious high-fat, high-carb snacks to keep you fueled up for that game of roulette—cravings for such fare increase as sleep decreases.
Loss of sleep directly affects mechanisms in our brains. Our prefrontal cortex is especially susceptible to effects from poor sleep. It acts as our brain’s command center, decision maker and emotion regulator. It’s the hall monitor for our personal social behaviors. It’s a big deal when it’s not working at top pitch.
Another part of the brain that’s particularly affected by sleep loss is the ventral striatum, part of a complex network of structures that mediate our responses to anticipated rewards. Your ventral striatum is strongly activated when you anticipate things such as receiving money, tasting delicious food or receiving praise or social rewards.
The ventral striatum and other structures interact with the executive-type functions of the prefrontal cortex to evaluate things such as the value of a reward, the likelihood of receiving it and the risks necessary to achieve it. You can thank them when you’d like that bicycle in the window, but not so much that you’ll risk breaking the window to steal it.
Adolescents and young adults are a high-risk population when it comes to short sleep. Physically, they need 9 or more hours of sleep a night, but 9 in 10 report getting less than this. Their internal clocks change with puberty, so they don’t start feeling sleepy until late at night. School schedules typically demand they awake quite early. Their weekday-weekend sleep patterns often change drastically. They’re likely to stay up much later on weekends and sleep later in the day, which means their brains and bodies are struggling Monday morning to re-regulate their sleep cycle for the week.
Adolescents are also going through an astonishing period of physical, social and mental development. They have more freedom. They become more social. There are physical and hormonal changes in their brains that influence emotions, motivations, sexual feelings and impulses, and response to risk and reward. Their neurocognitive structures are becoming more mature, but it’s an ongoing process. They’re still making plenty of poor decisions. It all adds up to a period of great excitement and great hazard. Sexual behavior, alcohol and other drug use, criminal activity, and death by injury and suicide all increase at this time. Depression, anxiety and other mental health problems often emerge.
So, while healthy sleep is important at all ages, it’s especially vital during the vulnerable time of adolescence. The challenges adolescents face at baseline, simply through the normal process of human development, are in many cases exactly those exacerbated by poor sleep.
Much attention has been paid to issues such as adolescent depression, behavioral risks and emotional regulation. The health research field is exploring a wide range of physical and social determinants that might improve outcomes in these areas, but these are huge targets for change. I have an idea about using sleep training as an easier and possibly very effective avenue for improvement.
In our work with older adults, we often say that “sleep is the gateway variable.” It’s a much less loaded topic than depression, substance abuse, social isolation or cognitive decline. Participants in our study have been eager to sign up for our classes on improving sleep. We suspect they would not be so willing to join a group on depression or substance abuse. As they learn and practice new skills in our classes, they enjoy more refreshing sleep and often see improvement in other areas of their lives.
I’d like to try working with adolescents in a similar way. Better sleep is a much more concrete and achievable target for change than eradicating adolescent depression. There are immediate and easy-to-see benefits—feeling better, having more energy, being more alert. And additional advantages are likely to follow, including better school performance, healthier risk-reward choices and more successful emotional regulation.
We know good sleep is a valuable asset across the lifespan. I believe we are only beginning to learn just how important it can truly be.
Erin Cassidy-Eagle, PhD, (she/her) was a Director of Research at ETR.