Scientists have identified the brain’s ‘storytelling station’ in a discovery that could lead to early treatment of dementia.
It is located in the hippocampus – a region that controls memory where neurons link different distant events into a single narrative.
First author Brendan Kohn-Sheahy, a PhD student at the University of California at Davis, said: “Things that happen in real life don’t always add up directly.
“But we can remember the details of each event better if they form a coherent narrative.”
Volunteers underwent MRI (magnetic resonance imaging) as they learned and remembered a series of short stories.
They portrayed main and side characters and an event – and were created specifically for study.
The stories were constructed so some were connected, two-parters and others were not.
The participants were placed in the scanner as recordings – and the next day when they were asked to remember them.
The patterns of activity in the hippocampus were similar for learning pieces of a coherent story that were not connected.
The results, published in the journal Current Biology, showed that coherent memories are being woven together.
Mr Kohn-Shehey said: “When you get to the second event, you jump back to the first event and embed part of it in the new memory.”
When recalling stories that produced a coherent narrative, the hippocampus initiated more information about the second event than when recalling non-connected stories.
Mr Kohn-Shehey said: “The second phenomenon is where the hippocampus is forming a connected memory.”
Further tests found that the ability to recall the hippocampal activity of the second event was associated with the details the volunteers could remember.
Other parts of the brain are also involved in the process of memory.
But the hippocampus brings the pieces together over time and builds them into connected narrative memories.
Mr Kohn-Shehey said this could lead to better diagnostic tests for early stages of aging or memory decline in Alzheimer’s.
Potential dementia drugs have a high failure rate because they are prescribed to trial participants once the disease has taken hold.
The findings also open the door for more efficient assessment of damage to memory from brain injuries.
Part of a new era in working memory research. Neuroscientists study the basic processes of memory that involve disconnected pieces of information.
Psychologists have a tradition of observing how memory works to capture and associate events in the ‘real world’. The camps have started merging.
Mr Kohn-Shehey said: “We are using brain imaging to obtain realistic memory processes.”
Research on memory processes may eventually lead to better diagnostic tests for early stages of memory decline in aging or dementia, or for assessing damage to memory from brain injuries.
Mr Cohn-Shehey said: “People love stories. We find it easier to remember events when they are part of a wider narrative.
“But in real life, the chapters of a story do not follow smoothly from one to the next. Other things happen in between.
“The hippocampus is the brain’s storyteller – linking separate, distant events into a single narrative.”
Credit: www.independent.co.uk /