Why you can distinctly recall that school picnic after 20 years

Toronto: Why is it that some people have a richly-detailed recollection of past experiences (episodic memory), while others tend to remember just the facts without details (semantic memory)?

Actually, these different ways of experiencing the past are associated with distinct brain connectivity patterns that may be inherent to the individual and suggest a life-long 'memory trait', a new study from Rotman Research Institute, Canada, shows.

In the study, 66 healthy young adults (average age 24) completed an online questionnaire describing how well they remember autobiographical events and facts.

The participants had their brains scanned at Baycrest with resting state functional magnetic resonance imaging. The researchers focused on connections between the brain's medial temporal lobes and other brain regions.

Those who endorsed richly-detailed autobiographical memories had higher medial temporal lobe connectivity to regions at the back of the brain involved in visual processes, whereas those tending to recall the past in a factual manner (minus the rich details) showed higher medial temporal lobe connectivity to areas at the front of the brain involved in organisation and reasoning.