Broadcaster: BBC Radio 4
Genre: Panel discussion, Fire-side chat
In this special episode of the BBC radio programme All in the mind (28 mins), host Claudia Hammond discusses the basis of memory formation with three leading researchers Tim Bliss, Graham Collingridge and Richard Morris who have been major players in developing our understanding of memory.
Tim Bliss draws attention to Donald Hebb’s pivotal book The Organization of Behavior and the aphorism “Cells that fire together, wire together”. Graham Collingridge then introduces the notion of long-term potentiation (LTP) as the molecular basis of memory, and particularly the role played by NMDA receptors in learning and AMPA receptors in memory. Errors in the functioning of any of hundreds of proteins can have detrimental impact on memory. Under-activation of LTP can be a contributory factor to schizophrenia.Bliss goes on to discuss the importance of neuroplasticity. Many of the component parts have been identified, the challenge now is to work out how they interact together. You need the right amount of neuroplasticity – either too much or too little can be harmful.
Audience members offer a number of fascinating case studies for the panel to discuss. For example a woman who exhibited increasing memory loss on an everyday basis but at night could sleep talk fluently in four different languages she had known in her younger life.
Forgetting some things is crucial in distinguishing the important things to remember, as well as the trivial which we do not need to store in our brains (but some do). Whilst agreeing that overall the brain cortex cannot get “full”, the panelists disagreed as to whether or not the hippocampus specifically can get saturated. This leads into consideration of whether the role of sleep is to allow the individual to move these memories out to somewhere else, to “clear the slate”.
The conversation moves onto the potential to lose memories such as PTSD or phobias by pharmaceutical interventions at a key moment of the consolidation-reconsolidation cycle. Memories get taken in and out of long-term storage, and the suggestion is made that when you are remembering something you may actually be remembering your most recent previous recollection of those events. Emily Holmes’ work on the Tetris effect is also discussed.
At the time of writing, this episode can also be downloaded from the BBC website.