HOXB8 and Anxiety: The components that are critical for achieving Hoxb8 microglia dependent induction of anxiety and/or grooming in wildtype C57Bl/6 mice are: Hoxb8 microglia, Hoxb8IRESCre (a Cre driver specific to Hoxb8 microglia within the CNS), Ai32 (a Cre dependent light activatable channel-rhodopsin 2 and YFP as a fusion protein), the dorsomedial striatum (DMS), the basolateral amygdala (BLA), central amygdala (CeA) and ventral CA1 (vCA1) region of the hippocampus, the exposure to laser power (mW) and an adequate duration of light exposure (min).