![]()
With the long Thanksgiving holiday weekend almost here, most of you are probably already preparing to entertain family and friends. And one of the things I've enjoy most about the season is sharing fond recollections of holidays long past, but never forgotten, with loved ones.
Ever wonder where those long-stored memories you pull out specially for the holidays come from? Using functional magnetic resonance imaging (fMRI) to probe brain activity and a diary method to collect memories, Canadian researchers believe it all depends on what you're thinking about.
Researchers have known for decades thinking about autobiographical facts is different from autobiographical episodes that happened only once. Since both kinds of thoughts can occur at the same time when people talk about their past, researchers have struggled to find an effective way to separate them.
Over a period of several months prior to the brain scan, volunteers documented dozens of unique events from their personal lives (episodic memories) and, at the same time, recorded statements about personal facts of their lives (semantic memories). Then, researchers played these recordings back to volunteers while their brains were being scanned.
The results showed these two types of autobiographical memory engaged different parts of the brain, even when the memories concerned the same contents.
The ability to richly re-experience autobiographical memory is thought to be unique to humans and is important for advanced decision-making and a better quality of life. This form of memory more strongly engaged parts of the frontal lobes involved in self-awareness, as well as areas involved in visual memory.
Science Daily November 23, 2004