Researchers identify mechanisms of memory

Washington, Apr 24 : Scientists at the University of Bristol have taken a major step forward in understanding how memory works, by identifying cellular and molecular mechanisms that may provide a key to understanding processes of recognition memory.

Our ability to remember the objects, places and people within our environment is vital for everyday life, though the importance of this is only fully appreciated when recognition memory begins to fail, as in Alzheimer's disease.

Scientists led by Zafar Bashir, Professor of Cellular Neuroscience, have achieved the breakthrough by successfully preventing visual recognition memory in rats by blocking certain mechanisms that control the way that nerve cells in the brain communicate.

"This is a major step forward in our understanding of recognition memory. We have been able to show that key processes controlling synaptic communication are also vital in learning and memory," said Bashir.

It is crucial that one possess the ability to recognise elements in the surrounding environment such as faces or places, as well as the ability to learn about that environment, for a normal functioning in the world.

Bashir tested a particular hypythesis behind memory mechanism, which says that changes at the specialised junctions (synapses) between nerve cells in the brain hold the secrets to learning and memory. The change in the strength of communication between synapses is called synaptic plasticity and, it is believed, the mechanisms of synaptic plasticity may be important for learning and memory.

"Nerve cells in the perirhinal cortex of the brain are known to be vital for visual recognition memory. Using a combination of biological techniques and behavioural testing, we examined whether the mechanisms involved in synaptic plasticity are also vital for visual recognition memory," said Dr Sarah Griffiths, lead author on the paper.

Through their experiments, they successfully identified a key molecular mechanism that controls synaptic plasticity in the perirhinal cortex. Later, they showed that blocking the same molecular mechanism that controls synaptic plasticity also prevented visual recognition memory in rats.

This indicated that such memory relies on specific molecular processes in the brain.

Bashir added: "The next step is to try to understand the processes that enable visual memories to be held in our brains for such long periods of time, and why these mechanisms begin to break down in old age."

The research is published online in Neuron.

ANI