Plasticity and neurogenesis
Shows that the brain's wiring changes with experience — and that drugs can speed up, slow or damage those changes.
Where this fitsConnects to 1 · Unlocks 2
- Connects to
- The synapse: release, binding and termination — Plasticity changes which synapses exist and how strong they are.
- Unlocks
- Glutamate and GABA: the brain's accelerator and brake — NMDA receptors are the molecular switch for 'fire together, wire together'.
- Fast doors and slow keypads: ionotropic and metabotropic receptors — BDNF acting on TrkB receptors supports plasticity and neuron survival.
Walk through
Rewiring at dendritic spines
New connections form at dendritic spines — small protrusions on dendrites. An acute burst of spine growth is a proxy for greater plasticity.
Analogy and worked example
Analogy: A garden path: walk it often and it becomes a clear trail (strengthened synapse); stop using it and weeds take over (pruning). New seedlings (neurogenesis) can sprout, and some chemicals act as fertilizer while others act as weed killer.
A study shows a drug causes a burst of new dendritic spines, followed days later by fewer spines. Is that good or bad?
- A burst of spine growth signals increased plasticity.
Tip: the ← and → keys move through the lesson.
Full lesson: Plasticity versus neurogenesis