The point of no return in choice reaction time: Controlled and ballistic stages of response preparation.

Abstract

A countermanding procedure and race model are used to assess separately the effects of experimental factors before and after the "point of no return" in response preparation. The results reveal details about processes that so closely precede the initiation of movement that they cannot be inhibited. These processes appear to be affected by the repetition of stimulus-response pairs, but not by the physical or semantic properties of the stimuli. A model of response preparation is supported in which response inhibition depends upon the outcome of a race between independent excitatory and inhibitory processes, and reaction time is the sum of the durations of at least two stages, separated by the point of no return.

On the ability to inhibit thought and action: General and special theories of an act of control.

“…The model also predicts that changes in stop-signal delay can compensate for changes in go RT to align inhibition functions from different conditions, strategies, tasks, and subjects (Logan, 1981;. This prediction justifies the common practice of adjusting stop-signal delay with a tracking procedure to produce a desired probability of inhibition (Logan et al, 1997;Osman et al, 1986).…”

“…When plotted as a cumulative distribution, the minimum go RTs are about the same for signal-respond RTs from different stopsignal delays and for go RTs from no-stop-signal trials. The distributions fan out at the higher quantiles, rising more slowly the longer the stop-signal delay (Osman et al, 1986). Example distributions of go RTs from signal-respond and no-stop-signal trials are plotted in Figure 2.…”

Impulsivity and Inhibitory Control

“…Most often, stop-signal delays are selected at random from a fixed set that is held constant throughout the experiment (e.g., Logan & Cowan, 1984), but many researchers let them vary dynamically, contingent on the subject's behavior (e.g., Osman et al, 1986Osman et al, , 1990Schachar & Logan, 1990;Schachar et al, 1995). The new method for estimating stop-signal reaction time uses a tracking procedure in which stop-signa!…”

“…Our measure of inhibitory' control comes from the stop-signal paradigm (Lappin & Eriksen, 1966;Logan & Cowan, 1984;Logan, Cowan, & Davis, 1984;Oilman, 1973;Osman, Komblum, & Meyer, 1986, 1990Vince, 1948), The paradigm involves two concurrent tasks, a go task and a stop task. The go task is a choice reaction time Address correspondence to Gordon D. Logan, Department of Psychology, University of Illinois, 6()3 Easi Daniel St,, Champaign, IL 51820; e-mail: glogan@s.psych,uiuc.edu.…”

Response Execution and Inhibition in Children with AD/HD and Other Disruptive Disorders: The Role of Behavioural Activation

“…The outcome of the race depends on the speed and the variability of the go process, the delay between go stimulus and stop signal, and the speed and the variability of the stop process. In the present study, a tracking algorithm was used to vary dynamically the delay between go stimulus and stop signal, contingent on the subject's performance (Osman, Kornblum, & Meyer, 1986Logan, Schachar, & Tannock, 1997). The initial delay between go stimulus and stop signal was 250 ms.…”