The Sticky Switch
ΔFosB
In depth
The one transcription factor that does not reset. Every other Fos protein clears within hours; this one lacks the two tags that mark it for destruction, so repeated reward stacks it up in the nucleus accumbens and stays for weeks after the last exposure. Scoped here to the reward circuit and the addicted state: in the chronic-stress literature the same molecule reads as a resilience marker, and short-term expression moves opposite to long-term, so this node is the long-term reward-sensitization arm only and makes no claim outside it.
What it drives
It increases Reward circuit.
Together, these findings demonstrate that drugs of abuse and natural reward behaviors act on common molecular and cellular mechanisms of plasticity that control vulnerability to drug addiction, and that this increased vulnerability is mediated by ΔFosB and its downstream transcriptional targets. doi 10.1523/JNEUROSCI.4881-12.2013
See it on the map
Open the causal map to follow this pathway upstream and downstream, arrow by arrow, each with its study.