Lesson 14a. Lifestyle Matters: Effects of Stress

School is stressful. Students also commonly must deal with emotions arising from boy-girl problems, over-bearing parent problems, bullies, worries about school, frustrated attempts to be popular, and their future. College students have enormous adjustments to make in the transition from leaving home and the cloistered environment they were used to in high school. Older adults returning to school have to cope with paying the costs, finding time for the family, and for the job.

The aspects of lifestyle that have the greatest direct effect on learning deal with stress, exercise, and sleep. This post explores stress.

Stress

 All learning at some point involves stress. Acute stress, which releases adrenalin, can be a good thing. It pumps you up and promotes focused attention. However, chronic stress impairs learning. When students struggle to improve, chronic stress ensues and creates a vicious cycle in which the stress impairs performance, which produces still more stress.

I have written numerous science-based posts on the bad effects of chronic stress on the brain. To review these and type “stress” into the search field of this blog.

Scientists have long known that chronic stress is bad for your brain. Adolescence seems to be an especially vulnerable time. Not only is the adolescent brain still being built, the brain is being re-built during the teen years.

Human imaging studies show the cerebral cortex shrinks during adolescence. In a recent study of "adolescent" rats, researchers found that the cortex shrinks in both males and females, and there is a loss of neurons in the ventral prefrontal cortex, the part of the brain humans use to make rational decisions and do higher-level thinking. More loss occurred in females than in males.

Until now, the reason for brain tissue loss has not been clear, but we may be able to explain it by considering the stresses that afflict teenagers, who routinely endure peer dismissiveness and bullying. Numerous animal studies show that stress impairs brain function and memory. Even single bullying exposures can be damaging.

Similar results have been reported in multiple humans studies. Here is a very real example of stress-related memory impairment from human bullying in schools that few may realize. In the study, young healthy men were tested for their ability to recall lists of 10 positive, 10 neutral, and 10 negative words. The men were given two minutes to learn the lists and were then tested immediately. Thirty minutes later they were given a psychosocial stress which included a fictitious job interview in front of live interviewers and counting backwards in steps of 17 in front of judges. Control groups did a five-minute speech and did the same counting, but not in the presence of judges. The next day, subjects were tested again (delayed recall) 10 minutes after cortisol injection. Other psychological tests were administered and the amount of cortisol in the saliva was measured at several key points in time.

The stressed group had elevated cortisol levels even though the stress was mild. Recall of both negative and positive emotionally arousing words was impaired, but there was no effect with neutral words. These effects could not be attributed to decreased attention or working memory span, which memory tests showed were not affected by the stress. Providing cues for recall eliminated signs of the stress effect on emotionally charged words.

So, this study shows recall of emotionally charged information can be impaired under stressed conditions. Imagine how great the deleterious effect of stress could be in situations where there is real stress, as in witnessing car accidents, crimes, or dangerous situations in which recalling what happened could be very important. Studies like this are consistent with many real-life observations with eye-witness accounts, where what is remembered may well be false.

The most obvious stressor for students comes from examinations. “Test anxiety” causes students to choke, typically failing to recall information they know they know, but just can’t dredge up under stressful test conditions.

A couple of studies have shown that test scores rise if anxious students are allowed to write about their test worries for 10 minutes just before a test. It also works to write down attributes of successful problem solving just before a test.

Why does this writing alleviate test anxiety? One study showed that such writing increased student engagement in the test. That is, students who were anxious were distracted by their anxiety and did not fully engage in solving the problems in the test.

Such writing before an exam is only beneficial for students who suffer from test anxiety. Other students don’t need this, and may in fact do worse by such a distraction. The best way to deal with choking on tests is to: 1) thoroughly know and understand the material being tested, and 2) develop long-term confidence by a string of test successes. If you truly “know your stuff” and believe in your ability as a student, there is no justification for test anxiety.

 Next Lesson: 14b. Lifestyle Matters: Exercise

Stress Sources:

Merz, Christian (2010). Stress impairs retrieval of socially relevant information. Behavioral Neuroscience. 124 (2), 288-293.

Newcomer, J. W., Selke, G., Melson, A. K., Hershey, T., Craft, S., Richards, K., et al. (1999). Decreased memory performance in healthy humans induced by stress-level cortisol treatment. Archives of General Psychiatry, 56, 527–533.

Vogel, Susanne (2016). Learning and memory under stress: implications for the classroom. Science of Learning 1(1), 16011. DOI: 10.1038/npjscilearn.2016.11

Young, A. H., Sahakian, B. J., Robbins, T. W., & Cowen, P. J. (1999). The effects of chronic administration of hydrocortisone on cognitive function in normal male volunteers. Psychopharmacology (Berl), 145, 260-266.

Zoladza, Phillip R., Ashlee J.Warneckea, Sarah A.Woelkea, Hanna M.Burkea, Rachael M.Frigoa, Julia M.Pisanskya, Sarah M, Lylea, Jeffery N.Talbotb (2013). Pre-learning stress that is temporally removed from acquisition exerts sex-specific effects on long-term memory. Neurobiology of Learning and Memory. 100, 77-87 https://doi.org/10.1016/j.nlm.2012.12.012