By Althea Need Kaminske
Cover image by Mizuno K from Pexels
Recently, Cindy talked about how the Yerkes-Dodson Law (or performance-arousal) is less of a law and more of a nice story about how stress influences performance. The performance-arousal curve is a handy explanation for a lot of different patterns and, on the surface, it seems to tell an interesting story about how stress affects our performance. Further complicating the story, the label of Yerkes-Dodson Law itself is incorrect. The performance arousal curve was developed independently of the results of the Yerkes-Dodson experiments, some 50 years later. This curve that is typically shown when talking about Yerkes-Dodson later conflated with Yerkes-Dodson and could more appropriately be called the Hebbian performance-arousal curve (1).
This is a lot to take in. Reader, I was shocked. I was shook. I have taught this “law” as part of my classes for the last decade. I was also more than a little embarrassed and slightly horrified that I had passed on bad information to my students without question. But, one of the joys of science is being wrong! If something is important enough for me to examine and think critically about, then I have to be open to being wrong about it. As uncomfortable as it is to find out you were wrong, I ultimately believe that it’s better to care enough to find out, than to not. (The ability to be ok with being wrong is, as it turns out, an important component of critical thinking (2)). And, ultimately, this led to a series of other questions for me to investigate. One of which was “Well, then how does stress affect memory?”
“Fight-or-flight”
When we are presented with a stressful event, a variety of hormones, neurotransmitters, and peptides are released in our brains. All of these things work to activate systems to help us cope with the stressor. This initial response is typically referred to as the “fight-or-flight” response. If you were walking in the woods and actually saw three bears your fight-or-flight response would put your system on high-alert. Your body diverts resources from less-pressing matters, like digestion, and focuses on giving you superhuman strength and speed. Your heart rate goes up as blood is pumped to muscles, your blood sugar goes up as your body creates more fuel, and your breathing rate increases as you burn that fuel. Your muscle tension is increased and your pupils dilate so you can take in more visual information. You’re primed and ready to fight or take flight (Note: The U.S. National Parks Service does not advise fighting bears. Nor do they advise running away from bears. You should calmly identify yourself, pick up any small children, and back away slowly https://www.nps.gov/subjects/bears/safety.htm ). This response is not always useful.
