Fig. 1.

Circadian gene expression patterns of four canonical circadian clock genes in the NAc (Top), caudate (Middle), and putamen (Bottom). In the scatterplots, each dot represents a subject, with the x axis indicating TOD on a ZT scale (−6 to 18 h) and the y axis indicating level of transcript expression. The red line is the fitted sinusoidal curve. Confidence intervals (90%) of peak estimates are depicted by the red bar in each plot. All four clock genes show rhythms in each striatal region, with consistent peak times across regions. Peak time and P values are located above each scatterplot.