A simplified schematic of a mushroom body compartment.

In both the left and right panels, the mushroom body compartment, indicated by the shaded box, is innervated by the axons of multiple KCs, the dendrites from one MBON and the axon terminals of one DAN. The bi-colored circles at the intersections of the KC axons and the MBON dendrites denote the KC-MBON synapses. Faintly shaded cell bodies indicate inactive neurons and boldly shaded cell bodies indicate active neurons. In the left panel, the DAN is inactive. In the right panel, the DAN is active and co-activation of the KCs and the DAN weakens the associated KC-MBON synapses (as illustrated by the smaller synapses).