Protocol - Inhibitory Control (Stop Signal Paradigm)

Description

STOP-IT is a computer-administered stop-signal task. Participants react as quickly as possible to a visual stimulus unless it is followed by an auditory stop signal presented after a variable delay. STOP-IT includes an analysis module (ANALYZE-IT) that calculates several summary variables.

For more conceptual information about the stop-signal task, please refer to the entry for the Stop-signal task in the Cognitive Atlas: http://www.cognitiveatlas.org/term/stop_signal_task

Specific Instructions

A compilation of research that has utilized this program can be found at www.psy.vanderbilt.edu/faculty/logan/#stopit

The task itself as compiled executable code for Windows 2k/XP can be downloaded from https://ore.exeter.ac.uk/repository/handle/10871/13860

Availability

This protocol is freely available; permission not required for use.

Protocol

Summary of the STOP-IT Stop Signal Task

The stop-signal procedure consists of a visually based primary task, followed 25 percent of the time by an auditory-based stop signal. For the primary task, participants differentiate between a square or circle by pressing a specific key as quickly as possible. The visual cues remain on the screen until the participants respond or 1,250 milliseconds (msec) expire. For the stop-signal task, the visual cue is followed, after a variable length of time (initially 250 msec), by a tone that signals to the subject not to respond. If the participant successfully inhibits their response, the stop-signal delay increases by 50 msec. If the participant does not successfully inhibit their response, the stop-signal delay decreases by 50 msec.

STOP-IT includes a practice phase of 32 trials followed by an experimental phase of three blocks of 64 trials (total). The number of practice and experimental phase trials can be adjusted.

Scoring

Results are written to an output file that includes block number, trial number, type of trial, whether the response was correct, reaction time, and stop signal delay. The ANALYZE-IT software calculates the means for a variety of summary variables including an estimation of stop signal reaction time (SSRT), where longer stop signal reaction time indicates greater motor impulsivity.

Personnel and Training Required

STOP-IT can be administered by research assistants trained in the ethical and competent use of psychological tests.

Equipment Needs

STOP-IT can be installed on computers running Windows 2000/XP.

Requirements

Requirement Category	Required
Major equipment	No
Specialized training	No
Specialized requirements for biospecimen collection	No
Average time of greater than 15 minutes in an unaffected individual	No

Mode of Administration

Self-administered evaluation

Lifestage

Child, Adolescent, Adult

Participants

Adults, adolescents, and children aged 7 years or older

Selection Rationale

The stop-signal task is a well-established, validated test of inhibitory control. STOP-IT is a freely available, precompiled executable program to perform the stop-signal task, which does not require further programming by the investigator.

Language

English

Standards

Standard	Name	ID	Source
Human Phenotype Ontology	Cognitive impairment	HP:0100543	HPO
Human Phenotype Ontology	Addictive behavior	HP:0030858	HPO
Human Phenotype Ontology	Impulsivity	HP:0100710	HPO
Human Phenotype Ontology	Disinhibition	HP:0000734	HPO
caDSR Form	PhenX PX530402 - Inhibitory Control Stop Signal Paradigm	6930461	caDSR Form

Derived Variables

None

Process and Review

On Nov 21, 2016, the Expert Review Panel 3 - Alcohol, Tobacco and Other Substances, and Substance Abuse and Addiction domains implemented the following changes for #530401 Inhibitory Control (Stop Signal Paradigm) to #530402 Inhibitory Control (Stop Signal Paradigm).

Field	Notes
Protocol ID
Protocol Name from Source	added STOP-IT task
Description	added link
Protocol	added link
Reference	added more refrences
Source	changed Gordon Logan to Frederick Verbruggen at the end
Specific Instructions	added
Status
Process and Review

On May 08, 2025, the Alcohol, Tobacco and Other Substances implemented the following changes for #530402 Inhibitory Control (Stop Signal Paradigm).

Field	Notes
Keywords	minor edits
Process and Review	minor edits

Protocol Name from Source

STOP-IT task

Source

Verbruggen, F., Logan, G. D., & Stevens, M. A. (2008). STOP-IT: Windows executable software for the stop-signal paradigm. Behavior Research Methods, 40, 479-483.

Executables for the STOP-IT task and the accompanying ANALYZE-IT analysis program can be downloaded from Frederick Verbruggen’s website (Department of Psychology, University of Exeter, UK).

General References

Boucher, L., Palmeri, T. J., Logan, G. D., & Schall, J. D. (2007). Inhibitory control in mind and brain: An interactive race model of countermanding saccades. Psychological Review, 114, 376-397.

Monterosso, J. R., Aron, A. R., Cordova, X., Xu, J. S., & London, E. D. (2005). Deficits in response inhibition associated with chronic methamphetamine abuse. Drug and Alcohol Dependence, 79, 273-277.

Nigg, J. T., Wong, M. M., Martel, M. M., Jester, J. M., Puttler, L. I., Glass, J. M., Adams, K. M., Fitzgerald, H. E., & Zucker, R. A. (2006). Poor response inhibition as a predictor of problem drinking and illicit drug use in adolescents at risk for alcoholism and other substance use disorders. Journal of the American Academy of Child and Adolescent Psychiatry, 45, 468-475.

van den Wildenberg, W. P. M., & van der Molen, M. W. (2004). Developmental trends in simple and selective inhibition of compatible and incompatible responses. Journal of Experimental Child Psychology, 87, 201-220.

Verbruggen, F., & Logan, G. D. (2009). Models of response inhibition in the stop-signal and stop-change paradigms. Neuroscience & Biobehavioral Reviews, 33, 647-661.

Smith, J.L., Mattick, R.P., Jamadar, S.D., & Iredale, J.M. (2014). Deficits in behavioural inhibition in substance abuse and addiction: a meta-analysis. Drug and Alcohol Dependence, 145, 1-33.

Protocol ID

530402

Variables

Export Variables

Variable Name	Variable ID	Variable Description	dbGaP Mapping
PX530402_Inhibitory_Control_
	PX530402010000	What is the calculated estimation of stop more signal reaction time? Longer stop signal reaction time indicates greater motor impulsivity. show less	N/A

Substance Use-related Neurobehavioral and Cognitive Risk Factors

Measure Name

Inhibitory Control (Stop Signal Paradigm)

Release Date

November 21, 2016

Definition

This measure assesses the ability of the participant to inhibit a response that has already been initiated.

Purpose

Inhibitory control is a component of impulsivity, and poor response inhibition is a risk factor for substance use disorders (Monterosso et al., 2005; Nigg et al., 2006).

Keywords

adolescent, Adult, Child, impulsivity, Inhibitory Control, STOP-IT, Stop-Signal, Stop-signal Paradigm, Stop-Signal Task, substance use disorder, , substance use, Vanderbilt University, SAA, Substance Use-related Neurobehavioral and Cognitive Risk Factors, computer administered

Measure Protocols

Protocol ID	Protocol Name
530402	Inhibitory Control (Stop Signal Paradigm)