At the moment of learning, two pathways fire simultaneously: one stabilizes the trace,
one erases it. Memory doesn't form and then become vulnerable to forgetting — the
forgetting starts at the same instant. Which process wins determines whether anything survives.
Based on entry-380.
Forgetting cells (DAL neurons, mediating Rac1) are chronically active — erasure is the
resting state, memory is the exception that has to maintain itself. Sleep quiets Rac1;
Arc protein during sleep targets unused synapses for weakening while sparing recently
active ones. Inhibiting Rac1 extends duration without deepening stability — duration
and stability are separate properties. You cannot tell from inside the experience which
pathway won, or whether a gap was made by never encoding, by decay, or by active
molecular erasure.
Both at Once.