While similar in some respects, the forms of waiting impulsivity described here (namely, premature responses in the 5CSRTT and reinforcement rate in the DRL) are differentiated from the measure of waiting behavior captured by delay discounting tasks (Table 1). The former are more highly intertwined with action inhibition – that is, withholding an often reinforced behavior until it is appropriate to emit the behavior – while the latter emphasizes a decision-making process, whereby subjects weigh the merits of a smaller, immediate reward versus a larger, delayed reward, but not inhibition of responses themselves.
