Figure 4.

There is a decrease in the ratio of parvalbumin (PV) to calbindin (CB) inhibitory neurons in area 9 of the human brain in autism. (A) Fluorescent photomicrograph shows the preferential laminar distribution of CB (red) in the superficial layers and PV (green) in the middle-deep layers of the human dorsolateral prefrontal cortex. (B,C) High magnification photographs of CB and PV neurons in the human dorsolateral prefrontal cortex (indicated by blue arrows). (D) Preliminary results show lower density of PV neurons in autistic cases (cells/mm³ ± standard deviation). (E,F) Low magnification photographs of PV neurons in the dorsolateral prefrontal cortex (indicated by blue arrows) of control and ASD adults.