Single cell 'can store memories'

Just one brain cell is capable of holding fleeting memories vital for our everyday life, according to US scientists.

A study of mouse brain cells revealed how they could keep information stored for as long as a minute.

A UK specialist said that understanding these short-term memories might help unlock the secrets of Alzheimer's Disease.

The finding was reported in the journal Nature Neuroscience.

If we can identify and manipulate the molecular components of memory, we can develop drugs... to hopefully allow a person to complete tasks without being distracted
Dr Don Cooper
UT Southwestern

The difference between the brain's long-term and short-term memory has been likened to the RAM of a computer and the hard-drive.

To perform normal functions, we need the ability to store,quickly and reliably, large amounts of data, but only a small amount ofthis needs to be retained in the longer term.

Scientists have spent decades working out which parts of thebrain are responsible for these functions, and how cells manage thisfeat.

Original theories suggested the memories were retained bymultiple cells forming "circuits" around which electrical impulses werefired for the necessary period.

More recent ideas have centred around the concept that even an individual cell could somehow hold on to information.

Researchers from the University of Texas Southwestern looked atbrain cells taken from mice using tiny electrodes to measure theirfunction.

They found that a particular component of the cells inquestion, a chemical receptor, which, when switched on, tells the cellto start an internal signal system that holds the "memory" in place.

Drug boost

The next step, they say, is to find out more about this internalsystem so that it could be targeted by drugs with the aim of improvingmemory.

Dr Don Cooper, the lead researcher, said: "If we can identifyand manipulate the molecular components of memory, we can develop drugsthat boost the ability to maintain this memory trace to hopefully allowa person to complete tasks without being distracted."

He said that this could potentially help people addicted to drugs, by improving the ability of their brain to ignore impulses.

Professor Ian Forsythe, from the University of Leicester, saidthat the information shed on the brain's ability to retain short-terminformation was important in understanding the laying down oflonger-term memories - and perhaps to understand how to help people forwhom that was a problem.

He said: "Probably the most interesting thing will be to get to grips with the memory problems involved in Alzheimer's Disease.