Alzforum readers might be forgiven for thinking all microglia do is act prominently, if mysteriously, in Alzheimer's pathogenesis. Not so. A recent flurry of papers shows that microglia can match themselves specifically to GABA synapses. They can revive plasticity in the adult brain by “shaving” its extracellular matrix and making room for new spine growth. They snip away healthy synaptic spines in reaction to stress. Scientists are studying basic mechanisms by which these changeable cells may influence depression, PTSD. Do these mechanisms underlie some of the effects that have sparked renewed clinical trials interest in certain psychedelic drugs?