New Studies Stress Importance of Environment in Cognitive Performance

Two new studies paint a clear picture of the long-lasting, corrosive effects of poor sleep on the brain by linking neighborhood conditions to memory loss and cognitive performance in adolescents. 

The first study found that persistent loud noises and other hallmarks of poorer neighborhoods, such as increased neighborhood density and the absence of trees which block light, disrupt sleep patterns in adolescents. 

The study was conducted by researchers from the Perelman School of Medicine at the University of Pennsylvania and published at the end of January through the Sleep Research Society and Oxford University Press. 

It studied 110 eighth and ninth graders for two weeks, looking at the length of sleep and environmental factors such as noise level, population and housing and street density, and tree canopy cover. 

This study concluded that noise levels and lack of canopy tree cover are associated with lower chances of these teens getting adequate sleep. 

National figures suggest that American adolescents don’t generally get adequate amounts of sleep. Recent figures from the US Centers for Disease Control, for instance, report that almost 60% of middle schoolers and a little more than 70% of high school students in the country get less than the recommended amount of sleep. Lack of sleep is connected to a host of health problems, including increased risk of obesity, diabetes, mental health issues, and behavioral problems. 

The researchers flagged this as a potential area for future policies promoting better sleep, which are associated with things like educational outcome and health.

A second study, conducted by researchers from the University of California Davis, inspected adolescent brain waves to show that a lack of sleep hurts memory and other cognitive functions of youth. 

This study looked at 77 people aged 9-16 over a three-year period. The participants kept a different sleep schedule for each of the three years, 7 hours, 8.5 hours, and 10 hours in bed, respectively. 

It concluded that the quality and length of sleep has an effect on the cognitive performance of adolescents when they are awake. 

Taken together, these studies show that the place in which someone grows up can have a quantifiably negative impact on their mental acuity through its impact on sleep. In the larger context of inequality, this means that education outcomes are tied to neighborhood environment. 

Policies that target these may affect education outcomes and, in the long run, some measures of inequality. 

“These two studies provide a snapshot of the research we fund to understand the harms of sleep deficiency and its causes,” said Marishka Brown, director of the National Center on Sleep Disorders Research at the National Heart, Lung, and Blood Institute, in a written statement. 

“They contribute objectively measured evidence of how modifiable environmental factors, such as housing and neighborhood conditions, impair sleep in adolescents and how that lack of sleep can literally be seen on the brain.”

You can read about the University of California Davis study here, and the Perelman School of Medicine, University of Pennsylvania, study here.