Uncovering the Mechanism of Memory Formation and Storage within the Brain
Potential Contribution to the Development of Brain Simulation Artificial Intelligence
“If the biological actuality of the brain's mechanism for memory formation and storage can be identified, we can know exactly where in the brain, in which neurons, memories are stored. This research contains the potential to prevent damage to memories in neurological disorders such as dementia or even to develop new biotechnologies to boost the formation of new memories. It could even become possible to selectively eliminate trauma-causing memories in PTSD (Post-Traumatic Stress Disorder) patients. The development of such technology will entail not just technological or academic advances but also huge social and economic impacts. Going forward, our research has significant potential to contribute to the development of neuromorphic artificial intelligence."
The World's First Proof of the Biological Existence of “Memory”
The human brain is made up of over 15 billion neurons and 500 trillion synapses. The brain not only controls all of the actions of the organism, it is capable of more rapid sensory processing than computers. Research on memory, the most abstract role of the brain, has gone through numerous trials and errors to finally grasp at the beginnings of an answer. However, the biological actuality of memory still remains a relatively unchartered territory in modern neurobiology and a mystery to solve.
Within this context, Professor Han Jin-hee's team at KIB have been utilizing various research technologies such as biochemical and molecular biological methodology, high resolution cell imaging, optogenetics, and behavioral analysis on mice in their quest to uncover the neurobiological actuality and principles behind learning and memory.
In order to test the idea that neurons with higher level of CREB (cAMP-response element binding protein) are preferentially recruited into a memory trace and artificially activating this trace would drive recall and modifications of that memory, the Herpes Simplex Virus was injected into the amygdala of laboratory mice to express two genes, CREB and TRPV1, simultaneously in the same cells. Then, combined approaches of drugs and genetic methods were used to artificially control the activity of target neurons.. When a drug that can bind to TRPV1 receptor and thus induce strong activation was applied to the CREB neurons, established fear memory was recalled even in the absence of any natural cue. In addition, same manipulation was found to be sufficient to induce modifications of that memory.
Another study was carried out with the objective of verifying whether memory could be introduced into the desired synapses based on optogenetics utilizing light as a way to control neuronal activity. As a result, it was discovered for the first time that the manipulated synapse was participating selectively in memory formation and that artificial stimulation of the synapse resulted in the expression of the memory.
This research project, which sprang from the question "Can the phenomenon of memory be explained and understood biologically?" contains potential value as fundamental research data for the treatment of neurological disorders such as dementia. Dementia clearly shows the consequences of memory loss. If these behavioral results were utilized to obtain a clearer understanding of the nature of memory, such neurological disorders causing memory impediments would be better understood and more effective treatments would be developed.
Above all, the biological nature and actuality of memory uncovered by Professor Han Jin-hee's team is expected to contribute greatly to the neurobiological science of memory by providing a new clue to fundamental scientific questions that remain unanswered. For example, it provides important information for identifying the mechanisms behind the storage and expression of fear memory, and its modifications such as strengthening of the memory for the treatment of various anxiety and fear-related psychological problems such as PTSD. Moreover, the current worldwide interest in artificial intelligence and the flow of investment into research and development on neuromorphic artificial intelligence also adds to the accomplishment of Professor Han Jin-hee and his team.
By discovering a principle for effective memory allocation and storage, this research is expected to greatly contribute to the development of artificial intelligence technologies that emulate how the human brain works.
Prof. Han, Jin-hee
2014 Annual Report