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context, and emotions—into a complete memory. Additionally, the hippocampus filters
information: repeatedly encountered or meaningful information is more likely to be
transferred into long-term memory.
Synaptic strengthening and LTP mechanism
After information is encoded, connections between neurons begin to change.
Initially, these connections are weak. However, when information is repeated or
frequently used, synaptic connections become stronger.
This process is called Long-Term Potentiation (LTP)—one of the most important
mechanisms in the neuroscience of memory. During LTP, the amount of
neurotransmitters increases, the number of receptors on neurons grows, and the synaptic
structure is modified to transmit signals more efficiently.
This shows that memory is not an abstract concept but is actually a physical change
in brain structure.
At early stages, memory depends heavily on the hippocampus. However, over time,
information is gradually transferred to the neocortex through a process called “systems
consolidation.” The hippocampus acts as an “index,” linking components of memories
stored across different areas of the cortex.
Memory consolidation during sleep
One of the most important findings in neuroscience is the role of sleep in memory
consolidation. During sleep, especially slow-wave sleep, the hippocampus reactivates
patterns of neural activity that occurred during learning—a phenomenon known as
“memory replay.”
This reactivation process helps transfer information from the hippocampus to the
neocortex, where memory is stored long-term. The coordination between different brain
waves—including slow oscillations in the cortex, sleep spindles in the thalamus, and
sharp-wave ripples in the hippocampus—creates an efficient communication system
between brain regions.
Many studies have shown that people who get sufficient sleep after learning
remember significantly better than those who are sleep-deprived. This indicates that
sleep is not merely a resting state but also a critical information-processing process.
Storage and retrieval of memory
After consolidation, long-term memory is stored in neural networks within the
neocortex. When needed, the brain reactivates these networks to retrieve information.
The retrieval process is not simply “opening” stored data but reconstructing the
entire neural network associated with that memory. Therefore, regularly using knowledge
helps maintain and strengthen neural connections.
An important feature of memory is its flexibility. Once stored in the neocortex,
information does not remain in its original form but can be reorganized and integrated
with existing knowledge. This process forms complex knowledge networks, providing the
foundation for deep thinking and reasoning ability.
2.1.2. Memory as a dynamic system
One of the most important discoveries of modern neuroscience is that memory is
not a static storage system. Instead, it is a dynamic system in which information is
continuously reinforced, restructured, and integrated.
This means that every time we recall an event, that memory can be updated or
altered. At the same time, learning new knowledge can influence how we understand and
organize previous knowledge.

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