The following repository includes a multi-armed bandit task where we examined the effect of delay on learning in individuals with ADHD as compared to controls. The project is part of Tal Locker's thesis project 22-23. Procedure: For this study, we recruited 24 individuals with ADHD, and 24 healthy controls (total of 48 participants). Participants were invited to take part in the study on campus. Participants performed a reinforcement learning, multi-armed bandit task, in which they were asked to make binary decisions to gain monetary rewards. In one condition, the reward was immediate, and in the other condition the reward was delayed by 7 seconds. Task: The task included four arms, illustrated as four distinct flowers (Figure 1). Participants were told that each of the four flowers lead to monetary reward with a different probability. In each trial the participant was presented with two flowers, randomly selected from the set of four, and randomly positioned at the left and right sides of the screen. Participants were asked to choose using a corresponding left or right response key press the flower they thought to be more rewarding. After making their choice, participants observed a rewarded (+ 1 gold coin) or unrewarded (0 gold coin) outcome. Trial sequence included a presentation of a fixation mark (1000ms), choice (until response with a 6000ms deadline), a choice feedback screen (500ms), and an outcome screen (1000ms). In half of the blocks the reward was immediate (1 sec) and in the other half the reward was delayed (7 sec) (Figures 2 and 3 respectively). The task started with an instruction phase, short practice, and then 200 trials (8 blocks containing 25 trials each). Preprocessing. We discarded trials with implausible short (<200ms) or long (>5sec) reaction times (1.62% of the overall trials). We then aimed to discard participants that overtly did not perform the task and repeated the response key selection from one trial to another more then 90% of the trials, or had implausible RTs more then 25% of the task, yet no participant reached criteria. Finally, we discarded the first trial in each block for all relevant analyses. ""