Do people with smaller amygdalas remember stressful events as clearly as people with regularly sized ones?
In most cases, we all remember acutely stressful times in our lives more clearly than a lot of other memories (“acutely” meaning immediately stressful, for example a haunted house or a near-death experience). These acute stressors lead to a surge of adrenaline that is to do more with our base instincts than any conscious thought. The amygdala plays a large part in this, and does lead to more clear memory of the stressful experience. As Cahill and McGaugh (1998) have explained, the link between the amygdala and memory is not causal, but its activation is what leads to these distinctly clear memories.
Does this mean that those with smaller amygdalas remember acutely stressful events less clearly, then? According to Welch, et al. (2009) people with learning disabilities and a small amygdala are more susceptible to suffering from schizophrenia. Interestingly, this could support a link between the amygdala and memory. Those that cannot remember will inevitably find it difficult to learn, so those with smaller amygdalas would naturally suffer from disorders in learning. This is supported by Exner, et al. (2004), who found that those in their sample of people with schizophrenia and smaller amygdalas characteristically had trouble learning.
So there is a definite link between the amygdala and memory, but is there a precise link between the two?
- Cahill, L., & McGaugh, J. L., (1998). Mechanisms of emotional arousal and lasting declarative memory. Trends in Neurosciences, 21(7). 294-299.
- Exner, C., Boucsein, K., Degner, D., Irle, E., & Weniger, G, (2004). Impaired emotional learning and reduced amygdala size in schizophrenia: a 3-month follow-up. Schizophrenia Research, 71(2-3). 493-503.
- Welch, K. A, Stanfield, A. C. The link to this journal article no longer works. I cannot find it anywhere else, so cannot finish citing it. Here is the link: http://journals.cambridge.org/abstract_s0033291709990870