Memory loss might occur if two crucial brain areas are out of sync

The learning, remembering, and retrieval of memories are aided by several unique groupings of neurons linked inside and across significant areas of the brain. According to a new research conducted by the universities of Bristol and Heidelberg, memories are lost if these neural assemblies fail to sync up at the proper moment.

How do you remember what has to be done next? What takes on in the brain when your mind wanders? The hippocampus and prefrontal cortex are two important parts of the brain that have a role in short-term memory. The goal of the study was to determine how various brain areas interact with one another as memories are created, preserved, and retrieved at the level of particular neuronal groupings. The research, which was written up in Currently Biology, also sought to determine why memory sometimes falters.

The concept of "neural assemblies"—groups of neurons working together to process information—was initially put out more than 70 years ago, but has proven challenging to identify.

Researchers have shown, with the use of rat brain recordings, that the dynamic interactions involving various neuronal assemblies created within and between the hippocampus and prefrontal cortex promote memory encoding, storage, and recall. The animals erred when the coordination of these assembly failed.

Lead author Dr. Michal Kucewicz, an assistant professor of neurology at the Gdańsk University of Technology and a former PhD candidate at the University of Bristol, said that these findings make it more difficult to focus memory restoration therapies both spatially and temporally. On the other hand, our research has shown crucial steps that affect whether remembering is successful or unsuccessful. On the level of neuronal assembly interactions, they provide plausible targets for therapeutic treatments.

"Our findings add to evidence that the neural substrates of memory are more distributed in anatomical space and dynamic across time than previously thought based on the neuropsychological models," said Matt Jones, professor of neuroscience in the School of Physiology, Pharmacology and Neuroscience and Bristol Neuroscience and senior author of the paper.

The next stage in the study is to alter neural assembly relationships, either with medication or with brain stimulation, as Dr. Kucewicz is now doing in patients, to see whether doing so will hinder or improve memory. The study team believes that the same processes might repair memory functions that have been affected by a specific brain illness in human patients.