New research finds that memories are formed in the brain likely due to the formation of new connections between cells, underscoring the importance of changes in synaptic wiring in learning and memory storage. What mechanisms enable our brains to absorb new information and form memories? Research led by Dr Tomás Ryan of Trinity College Dublin has revealed that learning involves the continuous creation of new connections between specially designed cells in various areas of the brain.
We are always learning, intentionally, accidentally, or accidentally, causing our brains to continually change. Our interactions with the world, each other, and media content result in the acquisition of new information and the creation of memories.
The next time we walk down the street, meet a friend, or come across something that reminds us of the last time we listened to a podcast, we quickly rekindle that memory somewhere in our brain. But how do these experiences change our neurons so that we form these new memories?
The brain's dynamic network
Our brain is an organ composed of a dynamic network of cells that is in a constant state of change due to growth, aging, degeneration, regeneration, daily noise, and learning. The challenge for scientists is to identify the "differences" that form memories - the changes in the brain where memories are stored, called "engraving", which retain the information for later use.
The newly published research aims to understand how information is stored as "images" in the brain.
Dr. Clara Ortega-de San Luis, a postdoctoral researcher in the Ryan Laboratory, is the main author of this article published in the international authoritative journal Current Biology:
"Memory scar cells are groups of brain cells that change themselves when activated by specific experiences to incorporate and retain information in our brains. Reactivating these memory 'building blocks' triggers recall of the specific experience associated with them. The question is, how do scars store meaningful information about the world?"
To identify and study the changes that occur in the "notches" that allow us to encode memories, the research team studied a form of learning in which two experiences that are similar to each other are linked by the nature of their content.
The researchers used a paradigm in which animals learned to recognize different situations and make connections between them. Using genetic techniques, the team labeled two different populations of memory cells in the brain for two different memories and then monitored how learning formed new connections between these memory cells.
Research results and significance
They used optogenetics, which uses light to control the activity of brain cells, to further demonstrate how learning requires these newly formed connections. In the process, they discovered a molecular mechanism mediated by a specific protein in synapses, which is involved in regulating the connections between brain cells.
The study provides direct evidence that changes in synaptic wiring connections between "nick cells" may be a mechanism for memory storage in the brain.
Commenting on the study, Dr Ryan, associate professor in Trinity's School of Biochemistry and Immunology, Trinity Institute of Biomedical Sciences and Trinity Institute of Neuroscience, said:
"Understanding the cellular mechanisms that allow learning to occur not only helps us understand how we form new memories or modify existing ones, but also helps us further understand how the brain works and the mechanisms it requires to process ideas and information. In 21st century neuroscience, we "Many people believe that memories are stored in engraved cells or their subcomponents. This study suggests that rather than seeking information within or on cells, learning may occur by changing the brain's wiring diagram - less like a computer and more like a developing sculpture."
In other words, the "nick" is not in the cell, the cell is in the "nick".