A new study, entirely Italian, published on Cortex Journal, unveiled the mechanism behind the exceptional memory of those individuals who can remember even the slightest detail of every single day of their life. By analysing these individuals, the researchers could identify specific areas of the brain purposely designed to give memories a temporal dimension, by organising information that in people with standard memory remains only a blurred and vague reminiscence.

Sapienza University, the Italian National Institute of Health, and the University of Perugia were also involved in the research, carried out in the Santa Lucia Foundation's laboratories in Rome and coordinated by Patrizia Campolongo, Valerio Santangelo, Tiziana Pedale, and Simone Macrì.

Eight people with Highly Superior Autobiographical Memory (HSAM), also part of the 2018 study conducted by the same team, were asked to remember a very distant event, dated back 20 years. Afterwards, their neural activity was measured in real time through functional MRI scan, a non-invasive technique which allows the researchers to observe the brain in action and identify the most active areas while remembering past events. A control group of 21 people with no particular abilities or memory deficits, was also asked to perform the same task.

By using a state-of-the-art technique called Multivoxel Pattern Analysis (MVPA), the researchers could then verify that the best neural representation of memories in the individuals with HSAM was indeed connected to the functional role of specific brain areas.

"The outcomes of this investigation – say the authors – show that when differentiating between old and new memories, for people with HSAM, we can detect a high specialisation in the ventromedial prefrontal cortex of the brain, an area we believe to be designated for organising superior cognitive functions. The same brain region seems to be less precise in people with normal memory leading us to "mixing up" the temporal dimension of old and new memories."

"Through the autobiographical memory, we are able to recall experiences about all our life, lending a temporal and narrative dimension to our existence – note the authors. Here, for the very first time globally, we have been studying the neurobiological mechanisms linked to the temporal dimension of memory through a state-of-the-art methodology and, above all, in a group made of "special" people."

The outcomes of this new scientific result are crucial, not only for the analysis conducted on these people's special gift but above all to open new frontiers for research on neurorehabilitation of memory and mnesic functions in patients with central nervous system injuries.

"Understanding the neurobiological systems underlying the hyperfunction of the memory – conclude the researchers – offers important indications on which areas are important to stimulate in order to adequately reactivate memory in people with neurological deficits or injuries."

References:

Enhanced cortical specialization to distinguish older and newer memories in highly superior autobiographical memory - Valerio Santangelo, Tiziana Pedale, Simone Macrì, Patrizia Campolongo. - Cortex 2020 https://doi.org/10.1016/j.cortex.2020.04.029

Further Information

Patrizia Campolongo
Department of Physiology and Pharmacology "Vittorio Erspamer" 
patrizia.campolongo@uniroma1.it