(A) Timing differences between control prehension behavior and prehension after laser termination (“rebound prehension”), averaged across 5 Slc32a1-COP4*H134R/EYFP animals. Values include First Lift (difference between First Lift and either the cue (control) or laser off (rebound)) and the intervals between sequential behavioral components. Within individual animals, First Lift timing (3/5 animals) and variance (5/5 animals) were also significantly different (Wilcoxon–Mann–Whitney rank sum, p<0.05). (B and C) Comparison of the trajectories of control (B) and rebound prehension (C) Trajectories (n = 20 trials) color coded by behavioral component. Top row displays trajectories from Lift to Grab, bottom row represents trajectories from Grab to At mouth. Circles represent on perch (gray), Grab (green), and At mouth (dark blue) hand position. (D) Rebound prehension was accurately performed from a diversity of starting positions. Control prehension from the perch (gray, n = 25 trials), rebound prehension from perch (dark blue, n = 25 trials), and rebound prehension from mid-air starting position (light blue, n = 18 trials) for a representative animal. Lines connect starting position of the reach to Grab position. Color-coded circles represent Grab position. (E) End-point quantification for control, rebound prehension from perch, and rebound prehension from mid-air trials for a representative animal. Box plots (whiskers mark minimum and maximum non-outliers) of Grab error: Grab error is defined as the distance between Grab position of an individual trial and median Grab position (control, success trials). No significant difference between control and rebound prehension from the perch or from midair positions (4/5 and 5/5 animals, respectively; Wilcoxon–Mann–Whitney rank sum, p>0.05). (F) Extinguishing the laser over contralateral sensorimotor cortex elicited rebound prehension even in the absence of a cue and pellet. (G) Laser-off over ipsilateral sensorimotor cortex did not generate rebound prehension. (F) and (G) Behavioral components denoted by color-coded bars. Blue sinusoidal line marks laser duration. Cumulative histogram of First Lift is shown. (H) Effect of laser duration on the likelihood of rebound prehension, initiation latency, and associated jitter in the absence of cue and pellet. Statistically significant (repeated-measures ANOVA, p<0.05) main effect of laser duration on rebound prehension initiation probability, delay, and jitter. (I) Rate of rebound prehension as a function of success and chewing status at laser off (average of 5 animals, bars are standard deviation). (J) Control (gray) and rebound (blue) prehension rates as a function of food deprivation (dep.) state. Animals (n = 4) were taken off food deprivation three times and the rates were averaged. Prehension rates plotted are the means of these averages, bars are standard deviation. Asterisks indicate statistical significance (t-test with unequal variance, *p<0.05, **p<0.001).