LAUSR

Significance It is a huge challenge to dissect the projection patterns of specific neurons with synaptic information in the whole brain. Here, we establish a pipeline for studying long-range projection patterns at the synaptic level and acquired whole-brain information of parvalbumin neurons in the basal forebrain. The synaptic terminals of parvalbumin neurons are widely distributed in the limbic system, including the hippocampus, thalamus, and mammillary body. In the mouse model of Alzheimer’s disease, we found that synaptic degeneration of parvalbumin neurons occurred in memory-related regions, which are inconsistent with amyloid-β plaque distribution. These works provided anatomical information for understanding how basal forebrain regulates downstream regions and the tools to investigate synaptic connections of specific neurons in the whole brain under physiological and pathological conditions.