How does the brain store memory?
1. Encoding:
Memory Encoding: The process by which information is received, processed, and stored in the brain.
Sensory Memory: Stores information for a brief moment, such as vision or hearing.
Short-Term Memory (STM): Holds a limited amount of information temporarily, usually for a few seconds or minutes.
Long-Term Memory (LTM): Stores information for an extended period, and it's the memory we usually refer to when talking about memory.
2. Storage:
Associative Networks: Memories are stored in interconnected pathways of neurons called associative networks.
Distributed Storage: Memories aren't stored in a single location but rather distributed across the brain.
Synaptic Changes: Long-term memory formation is associated with the strengthening of synaptic connections between neurons (called Long-Term Potentiation or LTP) and weakening of connections that are not used frequently (Long-Term Depression or LTD).
Neuronal Circuits: Memories may be stored within the firing patterns of specific neuronal circuits.
3. Retrieval:
Memory Retrieval: The process of accessing stored memories.
Recall: Retrieving information from memory without external cues.
Recognition: Identifying or selecting previously encountered information when encountering a familiar stimulus.
Reconstruction: Combining stored pieces of information to recreate complete memories.
4. Consolidation:
Memory Consolidation: The process of stabilizing newly acquired memories and moving them from short-term to long-term memory.
Systems Consolidation: The hippocampus is thought to play a key role in consolidating new memories, forming long-term memories through communication with other brain areas.
Protein Synthesis: The synthesis of new proteins appears to be essential for memory consolidation.
Sleep: Sleep is crucial for memory consolidation, particularly for declarative (fact-based) memories.
5. Reconsolidation:
Memory Reconsolidation: The process of reactivating a stored memory and updating or modifying it in light of new information or experiences.
Destabilization and Restabilization: Memory reactivation "destabilizes" the memory, allowing for modifications before the memory is restabilized in an updated form.
Impact on Learning: Reconsolidation can lead to either strengthening or weakening of memories, influencing memory recall and learning abilities.
6. Forgetting:
Memory Decay: Memories can decay or fade over time when not actively practiced or revisited.
Interference: Proactive interference occurs when previously learned information interferes with new learning, while retroactive interference happens when new information disrupts the recall of previously learned material.
Amnesia: Brain damage or neurological conditions can lead to amnesia, where individuals have difficulty creating new memories or retrieving stored memories.