Gateway to human memory pinpointed

Researchers have successfully determined the brain location where memories are generated with a level of precision never achieved before.
An international team led by researchers from the University of Magdeburg and the German Center for Neurodegenerative Diseases (DZNE) was able to pinpoint the location where memories are generated down to specific circuits of the human brain.
The researchers hope the results might be able to assist in acquiring a better understanding of the effects Alzheimer's disease has on the brain.
For the recall of experiences and facts, various parts of the brain have to work together. It is known that memories are stored primarily in the cerebral cortex and that the control centre that generates memory content and also retrieves it, is located in the brain's interior.

This happens in the hippocampus and in the adjacent entorhinal cortex.
"It is been known for quite some time that these areas of the brain participate in the generation of memories. This is where information is collected and processed. Our study has refined our view of this situation," said Professor Emrah Duzel, from DZNE in Magdeburg and director of the Institute of Cognitive Neurology and Dementia Research at the University of Magdeburg.

"We have been able to locate the generation of human memories to certain neuronal layers within the hippocampus and the entorhinal cortex. We were able to determine which neuronal layer was active.

"This revealed if information was directed into the hippocampus or whether it travelled from the hippocampus into the cerebral cortex. Previously used MRI techniques were not precise enough to capture this directional information.
"Hence, this is the first time we have been able to show where in the brain the doorway to memory is located," said Duzel.
For the study, the scientists examined the brains of persons who had volunteered to participate in a memory test. The researchers used a special type of magnetic resonance imaging technology called "7 Tesla ultra-high field MRI."
This enabled them to determine the activity of individual brain regions with unprecedented accuracy.

"This measuring technique allows us to track the flow of information inside the brain and examine the areas that are involved in the processing of memories in great detail," said Duzel.
The findings are published in the journal Nature Communications.