A little stress can be very beneficial, because it improves your learning speed and boosts motivation. But equally, if stress is severe and persists for a long time it can affect your mental health and cause a loss of brain cells.
You will certainly have experienced a stressful situation, especially over the last few weeks; waiting outside that exam room holding your notes with sweaty palms, paging through them while feeling your heart racing, your breath panting. You take a sip of water to relieve the sensation of drought in your mouth. Now you close your notes, you breathe heavily trying to relax, but the murmur of your course mates makes it worse. You enter the room, and the sight of the chairs all aligned next to each other further increases your stress level. You sit and wait. The invigilator then puts the exam paper on your desk. And finally it begins: “You can now start the exam, you have two hours”. You open it, skimming quickly through the questions and here it is, your memory seems blank and you have trouble focusing. Well the good news is you can blame it on your amygdala!
Firstly you need to know that the brain is split into several different sections; the more instinctive and primitive parts in the brain such as the striatum, hypothalamus and the amygdala, form a hierarchy, all controlled by the prefrontal cortex, which is situated behind your forehead. This simply means the caveman sections at the back of the brain are controlled by the spaceman sat at the front. The prefrontal cortex is the most evolved area of the brain and in normal conditions it is responsible for controlling our social behaviour and emotions. So why does this change under stressful conditions? The answer lies in your hormones and your neurones.
When your body is under stress, it releases a cascade of hormones, which causes the prefrontal cortex to surrender and transfer the control of our emotions to the more primitive parts of the brain. This causes the striatum and amygdala, the parts of the brain which regulate inappropriate actions and controlling emotions such as fear, respectively, to increase their activity, secreting dopamine and noradrenaline. High levels of those two hormones activate receptors in the brain, which open channels and prevent linkages between neurones. If neurones cannot link, the prefrontal cortex cannot control the amygdala and the striatum, and thus our emotions take over, causing mental paralysis and panic.
Neurones are the messengers in your brain, or in this analogy a time machine. The neurones are connected by dendrites. In stressful conditions the dendrites can be lost. If the stress is episodic, those connections have the ability to regrow, but if the stress becomes more chronic and long term, they will disappear permanently.
On top of this, glucocorticoid, another stress hormone, can also affect cognitive functions such as memory. The section of the brain used when learning something for an exam is the hippocampus – it consolidates information by transferring it from the short-term memory to the long-term memory. The problem with the hippocampus is that it contains glucocorticoid receptors. If glucocorticoids bind to those receptors in the hippocampus, the ability to convert short-term memory to long-term memory is reduced.
So here are some tips to help you reduce tension and increase your potential to remember during exams:
- The more often you introduce a piece of information in your short-term memory, the more chance it has to be transferred into your long-term memory. So instead of forcing yourself to learn, try to just look over the material as many times as you can.
- If the material is lacking context, make it meaningful! One way to do this is to associate the information you are trying to remember with an image as bizarre as possible.
- Test yourself! As much as you can, it will help you to focus your answer and get use to the question style.
- If the exam room is unfamiliar, visit the place the day before, paying attention to the little details, while listening to relaxing music. Your brain will associate the place with the music, reducing tension, on the day of the exam.
- Before the exam, try to recall an enjoyable place you’ve been to or a pleasant memory; remember the sounds, smells and colours associated to it. If you feel overwhelmed during the exam, take a minute to think about your pleasant memory. The happy memory will release serotonin, giving you a sensation of wellbeing and releasing tension.
Now that you know how stress affects memory, you can help stay in control and make the most of your potential!