Figure 2. Motivational Go/NoGo learning task and performance.
(A) On each trial, a Win or Avoid cue appears on screen. Subjects can respond during cue presentation. Response-dependent feedback follows. (B) In total eight cues are presented for which the correct response needs to be learned. (C) Each cue has only one correct response (Go-left, Go-right, or NoGo), which subjects can learn from the feedback. (D) Feedback is probabilistic. Correct responses are followed by reward (Win cues) or a neutral outcome (Avoid cues) in 80% of the time and by a neutral outcome (Win cues) or punishment (Avoid cues) otherwise. For incorrect responses, these probabilities are reversed. (E) Trial-by-trial proportion of Go responses (±SEM) for Go cues (solid lines) and NoGo cues (dashed lines), collapsed over Placebo and MPH. Left: All cue types. From the first trial onwards, subjects made more Go responses to Win vs. Avoid cues (i.e. green lines are above red lines), reflecting the motivational bias. Additionally, subjects clearly learn whether to make a Go response or not (proportion of Go responses increases for Go cues and decreases for NoGo cues). Right: Go cues only. For the Go cues, a Go response could be either correct or incorrect. The motivational bias is present in both correct and incorrect Go responses, but incorrect Go responses are unlearnt. Note that the total p(Go) in this plot sums up to the solid lines in the left plot. (F) Mean (±SED) proportion Go responses. Proportion Go responses is higher for Go vs. NoGo cues, indicative of task learning. Additionally, subjects made more correct and incorrect Go responses to Win vs. Avoid cues. Source data of task performance are available in Figure 2—source data 1.
DOI: http://dx.doi.org/10.7554/eLife.22169.004
Figure 2—figure supplement 1. Individual traces (black lines) and group average (coloured lines) of correct and incorrect Go responses using a sliding average of 5 trials.
