There is a complex relationship between stress and memory and, in particular, your short-term memory.
Facts you read, hear and study become memories through a three-step process: acquisition, consolidation and retrieval. New ideas have to be consolidated by the hippocampus, influenced by the amygdala, which emphasises experiences associated with strong emotions. The hippocampus then encodes the memory by strengthening the synaptic connections stimulated during the original sensory experience. Once the memory is stored, the prefrontal cortex usually retrieves that memory.
But, when stress is entered into the equation, what impact does this have on the process of saving and retrieving memories?
Stress can be psychological (work deadlines), chemical (smoking) and physiological (illness), but it is always biological. Whatever the cause of stress, it creates measurable changes in the body. The stress response is an evolutionary mechanism mediated by the sympathetic nervous system (SNS) and developed to protect the body at times of short-lived risk. Your brain responds to stressful stimuli by releasing hormones called corticosteroids which activate a threat response in the amygdala (the threat detection centre). This plays a crucial role in helping you to add meaning to what you’ve seen based partly on previous experiences and partly on in-built instinctive reactions. The amygdala sends a threat to the hypothalamus, which signals to the adrenal glands, releasing adrenaline into the bloodstream. This initiates a whole cascade of physiological processes in your body, including fast-beating heart rate, breathing rate increases, glucose and fats released into the blood as emergency energy for action and increased attention to potential risks in the environment ready to act.
You can see how this set of automatic responses can help some situations; however, more extreme stress has lasting adverse effects on the human body and brain.
Chronic stress is maybe the single most considerable risk to brain health. An extended period of sustained corticosteroids that result from chronic stress can damage the hippocampus and reduce the ability to create new memories. Activity is suppressed in the prefrontal cortex, which is vital for decision-making, planning and reason.
As we have seen, stress hormones influence almost every system in the body, from brain cells to blood sugar. Many of the physical symptoms of stress can be missed, so it’s essential to get familiar with the bodily manifestations of stress so that you can assess and address them as soon as possible.
In terms of psychological symptoms, these indicators could mean you’re under excess pressure:
Left untreated, stress can lay the foundations for depression and other mental illnesses, which is why it is important to take stress seriously.
Now that you understand the basics about the brain and memory process, it’s essential to factor in lifestyle changes that effectively manage stress levels and increase your brain health.