All stress is not bad. Some stress can be beneficial. However, chronic stress can affect brain size and structure, impacting learning and memory.
Stress becomes negative when it goes beyond our ability to manage it, turning it into long-term or chronic stress. Madhumita Murgia’s video, How Stress Affects the Brain, reveals that “Cortisol can literally cause your brain to shrink in size.” Long-term stress and overexposure to cortisol and other stress hormones increase the risk of myriad of health problems as described by the Mayo Clinic (2021), including:
Memory and concentration impairment
Sleep problems
Anxiety
Depression
Digestive problems
Headaches
Muscle tension and pain
Weight gain
Heart disease, heart attack, high blood pressure and stroke
Video
How Stress Affects the Brain, Madhumita Murgia
Understanding how stress effects the brain is important for all students and educators. A 2018 report from the American College Health Association reported that “more 60 percent of college students said they had experienced overwhelming anxiety in the past year” and “over 40 percent said they felt so depressed they had difficulty functioning” (Wolverton, 2019, para. 7). According to the CDC, from April 2019 through October 2020, the proportion of children between the ages of 5 and 11 visiting an emergency department because of a mental health crisis climbed 24 percent compared to that same time period in 2019 while the number increased by 31 percent for 12- to 17-year-olds. In a study conducted by the American Teachers Association, educators and school staff reported that they “found their work always or often stressful 61 percent of the time, significantly higher than workers in the general population, who report that work is always or often stressful only 30 percent of the time” (AFT, 2017).
When a threat is detected, the amygdala sends a distress signal to the hypothalamus which sets off a cascading alarm in the body that prompts the adrenal glands, which are located on top of the kidneys, to release a surge of hormones that include both adrenaline and cortisol. While adrenaline affects heart rate and blood pressure, cortisol increases sugars in the bloodstream and enhances the brain’s use of glucose (Mayo Clinic, 2021). “Chronic stress causes remodeling of dendrites and synaptic connections in many brain regions, including not only hippocampus but also amygdala and medial prefrontal and orbitofrontal cortex” (McEwen et al., 2016, p. 13). Figure 1 provides images of the effects of stress on neuronal structure.
Figure 1
Stress Effects on Neuronal Structure: Hippocampus, Amygdala, and Prefrontal Cortex (McEwen, Nasca & Gray, 2016)
Research at Yale University (2012), also found that chronic stress and depression can contribute to emotional and cognitive impairment, as well as loss of brain mass in the prefrontal cortex, which is involved in executive functions such as decision-making and planning. Furthermore, stress is a “potent inhibitor of adult neurogenesis” which refers to the birth of new neurons in the adult brain (Krugers et al., 2010, p. 2). Neurogenesis has been found to occur in the hippocampus and in the amygdala (Queensland Brain Institute, 2021). There is extensive literature on the profound effects of childhood stress and trauma on the brain relating to the amygdala and hippocampus.
The article “Learning and Memory Under Stress: Implications for the Classroom” by Vogel and Schwabe (2016) provides excellent detail on the memory stages, the effects of stress on learning, and considerations for educators (see Figure 2).
Provided below are critical key points shared by Vogel and Schwabe (2016) in "Learning and Memory Under Stress: Implication for the Classroom."
The effects of stress on memory are, however, not limited to the formation of memories (i.e., memory encoding and consolidation) but extend also to memory retrieval. Given that exams and tests can easily cause stress in students and students are evaluated based on their performance in these tests, it is particularly relevant to understand how stress affects memory recall. (p. 3)
Stress may lead to stronger memories for negative events happening in the classroom, such as failed exams, embarrassing experiences or interpersonal conflicts (e.g., bullying) and these strong negative memories may induce long-lasting frustration and a negative attitude towards school and the individual’s abilities. (p. 6)
Moderate or high levels of stress before exams will most likely hinder memory retrieval and lead to an underestimation of the students’ knowledge, putatively resulting in bad grades. (p. 6)
Stress may hinder the integration of new information into existing knowledge structures, which may prevent the updating of knowledge by new facts or a deep multidisciplinary understanding of concepts which is often required in education.. (p. 6)
Considering that stress is ubiquitous in education and even primary school children often report stress symptoms, understanding the effects of stress on memory is very important. (p. 7)
Figure 2
Effects of Stress on Memory, Vogel & Schwabe, 2016
Educators have the unique opportunity to design classroom environments (face-to-face, hybrid, HyFlex, online) that foster positive learning environments to support learning and enhance memory. Furthermore, educators have the opportunity within curricula and courses to teach students about the effects of stress on the brain to increase awareness and to introduce strategies to assist students learning how to manage stress which can be used over a lifetime.
As educators design content, presentations, activities, and assessments, they must consider the balance with quantity and quality so students are able to actively engage with the content, reflect, and transfer what they are learning across real-world contexts.
Author: Dr. Kristen Betts
Learn more about how INTERACT123 can support your work with engaging students in experiences that support learning and memory through mitigating stress to change the brain.