Figure 4.

Photostimulation. (a) Photomicrograph illustrating the location of the stimulation optic fiber fixed in the dorsolateral striatum as delineated by dashed white line. (b) Box plots summarizing all behavioral sessions during optostimulation. With continuous light (15 s) (left) animals displayed turning behavior similar to 6‐OHDA treated animals, that is, toward the side stimulated. With stimulation in patterned pulses (14 Hz) animals displayed turning behavior opposite to the stimulated side (right). Behavioral sessions lasted approximately 10–15 min divided as follows: a period of habituation (≈5 min) followed by three sequences repeated 10 times: 1–20 s pre‐stimulation, 2–15 s of light stimulation either delivered continuously or in pulses and 3–30–60 s post‐stimulation. As described in Section 3, a tracking system was used to automatically measure turning. A contour detection snapshot of a recorded mouse illustrates the deviated posture typical of an ipsilateral DA depletion, but in this case in an intact mouse during optogenetic stimulation