Although memory loss makes movies an attractive subject, in real life learning and memory may be the most interesting topics in brain science. How does the brain help us learn from everyday experience? Where are memories formed and stored in the brain? What is the mechanism of memory loss, whether it is caused by Alzheimer’s disease or by accident?
In a new study published in the seminary on July 5, a research team led by Professor Cao Peng from the Institute of Biophysics (IBP) of the Chinese Academy of Sciences provided some clues for the formation of brain memory.
In his famous Hebbian theory, Dr. Donald Hebb suggested that the brain learn new tasks or skills by modifying the efficacy of synaptic junctions between individual neurons. Although many studies support the “memory-synaptic specificity” hypothesis, until now, there is a lack of evidence to support this hypothesis. However, in this new study, Cao’s research team provided a direct experimental basis for the “memory synapse specificity” hypothesis.
IBP studies have shown that socially acquired olfactory memory is related to sudden long-term potentiation (LTP) events, which occur at specific types of synapses in specific olfactory glomerular neurons in specific glomerular units Up (Figure 1). This LTP lasts for at least two weeks.
By genetically manipulating the mechanism of IGF1 exocytosis, researchers have identified a detailed signaling pathway that mediates this new type of LTP, which has not been previously determined. In addition, studies have shown that this type of LTP is essential for olfactory memory, but not for odor perception, thus proving that this LTP at least partially encodes socially acquired olfactory memory.
On the 50th day of a romantic comedy, Lucy gets up every morning and can’t remember what happened the day before. Her memory loss was due to a car accident.
Testing and validating the “memory-synaptic specificity” hypothesis has been an ongoing challenge in brain science because it was previously impossible to connect specific types of synapses to specific behaviors and memories.
Cao and his team achieved this goal by using microcircuits in the olfactory bulb and mice that can be visually recognized using olfactory circuits associated with specific smells. This is the first proof that, in a specific type of synapse, LTP encodes a defined memory in the recognized circuit.
Many interesting and fundamental questions about learning and memory remain to be resolved, but this research provides a good starting point for future research.