Here is one possible way certain brain regions and systems could interact to produce a dreamspace with a vivid sense of ancient familiarity:
CA3 region of hippocampus: Repeated activation of this associative memory hub each time the dreamspace is revisited leads to strengthening of neural connections encoding the layout/details. Glutamate transmissions here help integrate dispersed bits into a coherent scenario.
CA1: Interfacing with prefrontal cortexareas, this region tags reactivated memories with emotional/salient data from the amygdala. Over time, places gain rich affective tone/coloring that contributes to their deep sense of significance.
Basal forebrain/brainstem: Neurons here fire probabilistically during REM sleep, releasing acetylcholine/histamine onto sensory cortices and hippocampus. This endogenous hallucinatory activity procedurally generates illusory perceptions/recollections that flesh out the imagined histories of the locale in ever-new ways.
Nucleus accumbens: Reward/motivation circuitry here links the dreamspace not just to memory but also to pleasure/comfort centers. Dopamine secretion reinforces returning to familiar comfort zones time and again within the dream narrative.
Striatum: As patterns repeat, procedural memories crystallize in these habit/motor loop circuits, allowing smooth unconsciously navigating of the dream world with intuitive spatial sense/fluid dream-logic.
Such an interplay of consolidation/association (hippocampus), emotion/salience tagging (amygdala/mPFC), endogenous imaging (basal forebrain), and favored unconscious habits (basal ganglia) could imbue dreamed places with the profound feeling of being beloved, meaningful locations woven throughout one’s entire inner experience and identity.
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