The human brain stores and processes memories in many different forms, and processes information by sending signals through synaptic connections between neurons. Narrative information is stored in the hippocampus and cerebral cortex, while non-narrative information is stored in different parts of the brain, including the striatum, cerebellum, and amygdala.
While many scientists have tried to unravel the mysteries of the brain, it has rarely revealed itself in its entirety. If we could figure out how and where the human brain stores memory information from the outside world, we could get closer to unlocking its secrets, but solving these questions is much more complicated and nuanced than it sounds. The brain is not a simple machine, and the way it works involves multidimensional processes that cannot be explained simply in terms of electrical signals or chemical reactions. How the brain processes so many signals and stores different forms of memory remains a mystery.
Many theories have emerged about how memory information is stored in the brain, but one of the most convincing is that it is accomplished by physical and chemical changes in synapses, the connections between neurons (nerve cells). There are about 100 billion neurons in the human brain, each of which forms thousands of synapses to form a complex network. This network plays an important role in the storage and processing of information. A synapse consists of a presynaptic neuron, which generates the signal, a postsynaptic neuron, which receives the signal, and a narrow gap between the two neurons, the synaptic cleft, which is about 20 to 50 nanometers wide. When a presynaptic neuron fires an electrical signal, its end releases a neurotransmitter into the synaptic gap, which stimulates a receptor on the postsynaptic neuron, which receives the signal and fires an electrical signal. The brain works because these signals are transmitted through a neural network of synapses to process information. The complex interaction of these synapses is one of the brain’s unique features, and understanding it is an important clue to understanding the nature of memory and learning.
The memory information that the brain receives is stored in different places depending on its type. The things we remember are broadly divided into narrative and non-narrative information. Descriptive information is information that can be expressed in words, such as schoolwork, movie plots, places or locations, or people’s faces. On the other hand, non-descript information is information that cannot be expressed in words, such as motor skills, habits, habits, and reflexive behaviors that we acquire through our bodies. Among these, the hippocampus, located in the medial temporal lobe of the brain, is known to be responsible for processing narrative information. This is illustrated by the example of a man who suffered damage to his hippocampus after a car accident, which impaired his narrative memory. However, he was able to recall all of his old memories from before the car accident. This suggests that the hippocampus is not the place to store long-term memories.
Many researchers point to the cerebral cortex as the place where narrative information is stored for a long time. Narrative information that enters the medial temporal lobe is temporarily stored in the hippocampus and its surrounding tissues, where it is broken down into neural signals that determine how it will be divided and stored. The medial temporal lobe is connected to a wide range of areas of the cortex through neural networks that relay this memory information to different parts of the cortex. Genes associated with memory are then expressed and proteins are made to solidify the memory content so that it remains stored for a long time. This process involves not just the accumulation of information, but the constant reorganization and strengthening of the brain’s neural network, which keeps memories alive.
Motor skills are stored in the striatum or cerebellum of the brain, while “habituation” memories, which are those that become desensitized to constant stimuli, or “sensitization” memories, which are those that continue to respond to similar stimuli after being stimulated once, are said to be stored in the neural networks that govern sensory or motor systems. Memories related to emotions or fear are stored in the amygdala. Each part of the brain plays a unique role in relation to a specific type of memory, demonstrating how intricately designed the brain is.
Understanding these complex memory storage mechanisms is more than just a matter of academic curiosity; it could have huge implications for treating neurological disorders and designing artificial intelligence systems. Research to unlock the secrets of the brain is still ongoing, and many challenges and discoveries await us in the future.
