Why do we forget?

The scientists behind this new theory - outlined today in the leading international journal Nature Reviews Neuroscience - argue that changes in our ability to acquire specific memories are based on environmental feedback and predictability

In an ever-changing world, such as that in which we and many other creatures live, forgetting some memories can be beneficial because it can lead to more flexible behavior and better decision-making

So, in effect, scientists believe that while we learn to forget some memories, we retain other important ones

The new theory was presented by Dr Thomas Lane, Associate Professor of Communication in the School of Biochemistry and Immunology and Trinity College's Neuroscience Institute at Trinity College Dublin, Dr Paul Frankland and Professor of Psychology at the University of Toronto and Toronto Children's Hospital

Dr Ryan and Dr Frankland are both members of CIFAR, a Canadian international research organisation that facilitated this collaboration through its Childhood and Brain Development project, which is conducting interdisciplinary work in this area

Dr Ryan, whose research team is based at Trinity Biomedical Sciences Institute (TBSI), said:

"Memories are stored in groups of neurons called 'memory imprinting cells,' and successful recall of these memories involves reactivation of these groups of neurons

"Our new theory proposes that forgetting is due to circuit reconfiguration that switches memory cells from accessible to inaccessible states

Dr Frankland added:

"Our brains have multiple ways of forgetting, but all of these ways make memory imprints -- the physical manifestations of memories -- more difficult to access

Referring to pathological amnesia in disease, Drs Ryan and Frankland noted:

"Importantly, we believe that this 'natural forgetting' is reversible in some cases, and that in disease states, such as those with Alzheimer's, these natural forgetting mechanisms are hijacked to greatly reduce memory Accessibility to cells, leading to pathological memory loss

Journal Reference :

1. Tomás J.