How Does Memory Work?
Memory is a complex process involving multiple stages and brain regions. It's not a single, static entity, but rather a dynamic system that encodes, stores, and retrieves information.
The process generally involves three main stages:
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Encoding: This is the initial stage where sensory information is transformed into a format that the brain can process and store. This involves attention and perception. For example, seeing a cat involves your visual system processing the shape, color, and movement, encoding it into a neural representation.
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Storage: Encoded information is then stored, initially in short-term memory (working memory), which has limited capacity and duration. If the information is deemed important, it moves to long-term memory. This process involves changes in the brain's physical structure, as described in the provided Lesley University article: “When long-term memories form, the hippocampus retrieves information from the working memory and begins to change the brain's physical neural wiring. These new connections between neurons and synapses stay as long as they remain in use." These changes involve the strengthening of synaptic connections between neurons.
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Retrieval: This is the process of accessing and bringing stored information back into conscious awareness. Retrieval can be effortless (like remembering your name) or require significant effort (like recalling a childhood memory). The Harvard University Bok Center emphasizes the importance of repeated learning and recall ("spacing effect") for long-term retention.
Types of Long-Term Memory
Long-term memory is further categorized, including:
- Recent memory: Relatively easily accessible memories from the recent past.
- Remote memory: Memories from the distant past, often less accessible.
The ECU Online article explains that changes in neuron electrical activity and neurotransmitter release across synapses build "circuits" in the brain, forming the basis for memory storage.
How Random Access Memory (RAM) Works (Computer Memory)
It's important to distinguish between human memory and computer memory (RAM). As explained in the Stack Overflow question about RAM, it operates on a principle of constant-time access. This means accessing any location in memory takes roughly the same amount of time, regardless of the location’s address.
