This is your brain on stress
The Amygdala and the Hippocampus working together
In learning situations, conscious memories are laid down by a system involving the hippocampus, and unconscious memories are established by fear conditioning mechanisms operating in the amygdala. These two parts of the brain operate parallel to one another and store varying types of information related to the learning experience.[1]
When a person is exposed to a stressful situation, the adrenal gland secretes a steroid hormone into the blood stream, which helps the body mobilize its energy resources to deal with the stress.[2] Because the amygdala is involved in the control of the release of adrenal steroids, when anxiety occurs, the amygdala sends messages to the thalamus, which then sends messages to the pituitary gland, which releases a hormone called ACTH. ACTH flows through the blood to the adrenal gland, causing it to release the steroid hormone. This steroid hormone flows through the blood to the brain, where it attaches to receptors in the hippocampus, amygdala, and prefrontal cortex.[3] When the steroid hits the hippocampus, signals are sent to the thalamus to tell the pituitary gland to slow down the release of ACTH. However, when the steroid reaches the amygdala, it tells the thalamus to tell the pituitary gland to keep releasing ACTH. If the stressful situation lasts too long, the hippocampus waivers in its ability to control the release of the stress hormone and to perform other routine functions.[4]
How stress can shrink your memory
Neuroscientist Bruce McEwen has shown how temporary severe stress can result in the dendrites in the hippocampus shriveling up. Dendrites are the part of neurons that receive input and are responsible for the beginning phase of long-term memory formation.[5] A study was done on a group of monkeys living under a dominant male who caused stressful situations. When some of the monkeys died, an autopsy was done in which stomach ulcers were found, suggesting that the monkeys had indeed been under stress. Notably, there was definite degeneration in each monkey’s hippocampus, but no other damage to any other part of the brain. More studies in humans injected with high levels of steroids, which mimicked the effects of severe stress, caused cells of the hippocampus to atrophy and die, and memory problems occurred as a result.[6] This explains one reason why performance anxiety can cause failure of memory for performance to occur.
Anxiety vs Fear
Anxiety and fear are related because both are reactions to potentially harmful circumstances. Fear is a reaction to external situations, but anxiety stems from an internal stimulation. Anxiety has been called unresolved fear; fear is related to behavioral acts of escape from threatening situations, and when these actions are not carried out, fear becomes anxiety.[7]For example, musicians may be afraid to play in public because of poor previous performances that caused peers to make fun of them, or because of a teacher criticizing them in front of others. When the musicians are called on to perform again, they are afraid because of the past bad memories of performance and do not want to set foot on stage in front of an audience. However, they are required to perform, and because they cannot act on their fear and run off stage, anxiety sets in. Research by LeDoux and Claparede suggests that it takes only one fearful experience to put in place an emotional memory that is nearly impossible to erase.[8] Thus a bad performance experience as a child can impact a musician even as an adult. If adult performers cannot pinpoint the bad experience causing them to fear performing, they may feel even more helpless to react against it, causing their anxiety to worsen. As seen previously, fear response in the brain is not connected to conscious memory, so the musician may never be able to pinpoint exactly his source of fear. The anxiety causes stress, and the stress causes the information-carrying dendrites to shrivel up. The more the performer stresses, the more the dendrites shrivel, making it harder to retrieve the music that has been stored in the hippocampus. Performers may hope to rely on their sensory motor skills to make it through the piece they are performing. However, as previously seen, stress hormones released by the amygdala affect the body’s reflexes, blood pressure, and temperature. Movements which once seemed effortless become quite cumbersome, and motor skill memory fails the performer.
Unfortunately, the problem of performance anxiety affecting memory is a rather cyclical one. As shown, performance anxiety has a direct impact on memory. However, memory also has a direct impact on performance anxiety. The better musicians feel they have a piece of music memorized the less they tend to feel stressed about a performance. Performers who prepare a piece of music very well may tend to let their mind wander during a performance. Consequently, they may begin to play automatically and turn their attention to the audience, which can distract them by calling attention to the social consequences of having a memory slip.[9]
Now that the process of how the amygdala and the hippocampus affect performance anxiety (memory of performance) and memory for performance, memory for performance and how to overcome performance anxiety will be discussed.
[1] LeDoux 1996, 239
[2] LeDoux 1996, 240
[3] LeDoux 1996, 240
[4] LeDoux 1996, 240
[5] LeDoux 1996, 242
[6] LeDoux 1996, 242
[7] LeDoux 1996, 242
[8] Horwitz 2002, 31
[9] LaBerge 1992, 53
Works Cited
Horwitz, Betty. Communication Apprehension: Origins and Management. New York: Singular Thompson Learning, 2002.
LaBerge, David. Attentional Processing: The Brain’s Art of Mindfulness. Cambridge: Harvard University Press, 1995.
LeDoux, Joseph. The Emotional Brain: The Mysterious Underpinnings of Emotional Life. New York: Simon and Schuster, 1996.