Differences in unity: The go/no-go and stop signal tasks rely on different mechanisms

Liisa Raud,René Westerhausen,Niamh Dooley,René J Huster

doi:10.1016/j.neuroimage.2020.116582

Liisa Raud, René Westerhausen + Show 2 more

Open Access

https://doi.org/10.1016/j.neuroimage.2020.116582

Copy DOI

Abstract

Response inhibition refers to the suppression of prepared or initiated actions. Typically, the go/no-go task (GNGT) or the stop signal task (SST) are used interchangeably to capture individual differences in response inhibition. On the one hand, factor analytic and conjunction neuroimaging studies support the association of both tasks with a single inhibition construct. On the other hand, studies that directly compare the two tasks indicate distinct mechanisms, corresponding to action restraint and cancellation in the GNGT and SST, respectively. We addressed these contradictory findings with the aim to identify the core differences in the temporal dynamics of the functional networks that are recruited in both tasks. We extracted the time-courses of sensory, motor, attentional, and cognitive control networks by group independent component (G-ICA) analysis of electroencephalography (EEG) data from both tasks. Additionally, electromyography (EMG) from the responding effector muscles was recorded to detect the timing of response inhibition. The results indicated that inhibitory performance in the GNGT may be comparable to response selection mechanisms, reaching peripheral muscles at around 316 ms. In contrast, inhibitory performance in the SST is achieved via biasing of the sensorimotor system in preparation for stopping, followed by fast sensory, motor and frontal integration during outright stopping. Inhibition can be detected at the peripheral level at 140 ms after stop stimulus presentation. The GNGT and the SST therefore seem to recruit widely different neural dynamics, implying that the interchangeable use of superficially similar inhibition tasks in both basic and clinical research is unwarranted.

Highlights

Response inhibition is fundamental for purposeful behavior, enabling us to adapt rapidly to changes in the environment
Stop accuracies were close to 50% and reaction times in unsuccessful stop trials were faster than go reaction times for each participant and at the group level (t (31) 1⁄4 21.48, p < 0.001, d 1⁄4 3.80)
This is in good compliance with the horse race model assumption stating that the reaction times in the unsuccessful stop trials should correspond to the left side of the go RT distribution

Summary

Introduction

Response inhibition is fundamental for purposeful behavior, enabling us to adapt rapidly to changes in the environment. Inhibitory control relies on a cascade of neural processes that result in the suppression of behavior, including signal detection and discrimination, response preparation, interference control, and, eventually, response inhibition. It is likely that successful inhibition depends on the fine-tuned interaction of multiple control systems, depending on the specific task requirements or strategies. In the GNGT, a proportion of the stimuli are replaced with a no-go stimulus, while in the SST, the go stimulus is always shown first, but may be followed by a stop stimulus after a short stop signal delay (SSD) Both the no-go and the stop stimulus instruct the participant not to respond, despite the prepared or possibly initiated go response. The defining difference between the two tasks is the timing of the inhibition signal relative to the go signal (0 and ~300 ms for the GNGT and SST, respectively)

Objectives

Methods

Results

Discussion

Conclusion