Light deprivation produces a sexual dimorphic effect on depression-like behavior.

Light deprivation induces more severe depressive-like symptoms in female mice.

Light deprivation leads to weaker locomotor activity in female depressive-like mice.

Light deprivation leads to lower excitability of L5PCs in female depressive-like mice.

Lower excitability of L5PCs may correlate with more severe depressive-like symptoms.