Document Type

Article

Journal/Book Title/Conference

Gait & Posture

Volume

71

Publisher

Elsevier BV

Publication Date

5-14-2019

First Page

1

Last Page

22

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Abstract

Background

Response inhibition involves suppressing automatic, but unwanted action, which allows for behavioral flexibility. This capacity could theoretically contribute to fall prevention, especially in the cluttered environments we face daily. Although much has been learned from cognitive psychology regarding response inhibition, it is unclear if such findings translate to the intensified challenge of coordinating balance recovery reactions.

Research question

Is the ability to stop a prepotent response preserved when comparing performance on a standard test of response inhibition versus a reactive balance test where compensatory steps must be occasionally suppressed?

Methods

Twelve young adults completed a stop signal task and reactive balance test separately. The stop signal task evaluates an individual’s ability to quickly suppress a visually-cued button press upon hearing a ‘stop’ tone, and provides a measure of the speed of response inhibition called the Stop Signal Reaction Time (SSRT). Reactive balance was tested by releasing participants from a supported lean position, in situations where the environment was changed during visual occlusion. Upon receiving vision, participants were required to either step to regain balance following cable release (70% of trials), or suppress a step if an obstacle was present (30% of trials). The early muscle response of the stepping leg was compared between the ‘step blocked’ and ‘step allowed’ trials to quantify step suppression.

Results

SSRT was correlated with muscle activation of the stepping leg when sufficient time was provided to view the response environment (400 ms). Individuals with faster SSRTs exhibited comparably less leg muscle activity when a step was blocked, signifying a superior ability to inhibit an unwanted step.

Significance

Performance on a standardized test of response inhibition is related to performance on a reactive balance test where automated stepping responses must occasionally be inhibited. This highlights a generalizable neural mechanism for stopping action across different behavioral contexts.

Download

Share

COinS