Fig. 2: Change of the dentate gyrus (DG) volume in the bright light exposure (BL) group and dim light exposure (DL) group.

a The left DG-head volume significantly increased (p = 0.002) in BL. b The left DG-body volume did not change significantly in BL. c The left DG-total volume significantly increased (p = 0.005) in BL. d The right DG-head volume did not change significantly in BL. e The right DG-body volume did not change significantly in BL. f The right DG-total volume did not change significantly in BL. g The left DG-head volume did not change significantly in DL. h The left DG-body volume did not change significantly in DL. i The left DG-total volume did not change significantly in DL. j The right DG-head volume did not change significantly in DL. k The right DG-body volume did not change significantly in DL. l The right DG-total volume did not change significantly in DL. *Indicates that the p values < 0.05, ** Indicates that the p values < 0.01.