Why we remember the past with great clarity

ANI: Many of us remember things from long ago as if they happened yesterday, but at times we forget what we ate for dinner last night. 

It's because how much something means to you actually influences how you see it as well as how vividly you can recall it later, according to a new study led by psychologists at the University of Toronto. 

"We've discovered that we see things that are emotionally arousing with greater clarity than those that are more mundane," said Rebecca Todd, a postdoctoral fellow in U of T's Department of Psychology and lead author of the study. 

"What's more, we found that how vividly we perceive something in the first place predicts how vividly we will remember it later on. 

"We call this 'emotionally enhanced vividness' and it is like the flash of a flashbub that illuminates an event as it's captured for memory," Todd stated. 

By studying brain activity, Todd, psychology professor Adam Anderson and other colleagues at U of T, along with researchers at the University of Manchester and the University of California, San Diego found that the part of the brain responsible for tagging the emotional or motivational importance of things according to one's own past experience - the amygdala - is more active when looking at images that are rated as vivid. 

This increased activation in turn influences activity in both the visual cortex, enhancing activity linked to seeing objects, and in the posterior insula, a region that integrates sensations from the body. 

"The experience of more vivid perception of emotionally important images seems to come from a combination of enhanced seeing and gut feeling driven by amygdala calculations of how emotionally arousing an event is," noted Todd. 

The study was published recently in the Journal of Neuroscience.