Changes in cortical structure as new memory encoded

A fascinating topic!

When new memories are encoded, significant changes occur in the structure of the brain's cortex. Here are some of the key changes:

  1. Neuroplasticity: The brain's neural connections, or synapses, are reorganized and strengthened as new memories are formed. This process is known as long-term potentiation (LTP).
  2. Synaptic pruning: As memories are consolidated, weak or redundant connections between neurons are eliminated, refining the neural circuitry.
  3. Neurogenesis: In some parts of the brain, such as the hippocampus, new neurons are born and integrated into existing neural networks.
  4. Dendritic spine formation: New dendritic spines, which are small protrusions on the surface of neurons, form and mature, allowing for increased communication between neurons.
  5. Axonal growth: Axons, the long, slender extensions of neurons, grow and branch out, enabling the transmission of signals between neurons.
  6. Myelination: The insulation around axons, known as myelin, is increased, allowing for faster and more efficient transmission of signals.
  7. Changes in cortical thickness: The thickness of the cortex, particularly in areas involved in memory formation, such as the hippocampus and prefrontal cortex, increases as new memories are encoded.
  8. Functional connectivity: The strength and coordination of connections between different brain regions, known as functional connectivity, are altered as new memories are formed.
  9. Neural oscillations: The patterns of neural activity, including oscillations in different frequency bands, are modified as new memories are encoded.
  10. Changes in gene expression: The expression of genes involved in synaptic plasticity, neuroprotection, and neuronal survival is altered as new memories are formed.

These changes occur in a hierarchical manner, with early stages of memory formation involving more rapid and widespread changes, and later stages involving more specific and refined changes.

Some of the key brain regions involved in these changes include:

  1. Hippocampus: plays a critical role in the formation of new memories, particularly episodic and spatial memories.
  2. Prefrontal cortex: involved in working memory, decision-making, and planning, and is also active during the consolidation of new memories.
  3. Temporal lobe: involved in the processing and storage of auditory and visual information, and is also active during the consolidation of new memories.
  4. Cingulate cortex: involved in attention, error detection, and conflict monitoring, and is also active during the consolidation of new memories.

These changes in cortical structure and function are thought to be essential for the formation and consolidation of new memories, and are critical for learning and memory.