Stress can interfere with the functioning of memory by either augmenting the impact and persistence of the recollection of an event, or by diminishing both. There are stressful situations in which we are unable to retrieve information that we have learned and thus should be readily available for recollection. This would be the case in a situation that carries enough stress to literally drain the blood supply from those regions of the brain that handle memory retrieval.
In contrast, we are also familiar with how well we seem to remember certain embarrassing, shameful, or frightening events from the past, which is an example of how stress can enhance our memory. This is the case in situations that carry such a strong power of emotional penetration that they burrow the deepest furrows in our memory circuits, often never to be forgotten and always readily recollected.
Finally, there are situations of chronic stress or stress associated with psychiatric disorders that are characterized by persistent hypo- (lower than normal) or hyperamnesia.
When Stress Attacks
Interaction with a stressor of sufficient strength that meets and surpasses the individual’s threshold of resistance leads to a cascade of neuroendocrine stress responses, which are in fact designed to attempt an adaptation (response) to the demands of the situation.