For many years the neuroscience community has debated the physiology of memory, and amnesia has become a somewhat controversial subject. Is memory irretrievably lost, or is it simply inaccessible? New evidence using light now seems to provide the answer.

Every experience we have stimulates neurons known as “memory engrams” which are activated as memories are formed. Sensory stimuli in everyday life re-awaken these engrams and memories are triggered. Thus we remember what we have experienced.

Researchers at the at Massachusetts Institute of Technology (MIT) and the Riken Brain Science Institute in Japan attached a protein to the engrams to enable them to be activated by light. Subsequent tests showed that the memory of an incident could be triggered in mice by exposing them to blue light.

Nobel prize-winning scientist and researcher for the project Susumu Tonegawa says the research indicates that “past memories may not be erased, but could simply be lost and inaccessible for recall”, and goes on to assert that the findings “will stimulate future research on the biology of memory and its clinical restoration”. The findings could provide new hope for Amnesia sufferers throughout the world.

Sources:

1. The Guardian:
   Amnesia researchers use light to restore 'lost' memories in mice.