Insulin Signaling Deficiency Produces Immobility in That Models Diminished Motivation States in Man and Responds to Antidepressants.

Defects in insulin signaling have been reported in schizophrenia and major depressive disorder, which also share certain negative symptoms such as avolition, anhedonia, and apathy. These symptoms reflect diminished motivational states, which have been modeled in rodents as increased immobility in the forced swimming test. We have discovered that loss-of-function mutations in the insulin receptor () and syntaxin () genes in , brief food deprivation, and exposure to DMSO produce immobility and avolition in non-dauer adults.