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Neural mechanisms underlying stop-and-restart difficulties: involvement of the motor and perceptual systems.

Yamanaka K, Nozaki D - PLoS ONE (2013)

Bottom Line: The ability to suddenly stop a planned movement or a movement being performed and restart it after a short interval is an important mechanism that allows appropriate behavior in response to contextual or environmental changes.However, performing such stop-and-restart movements smoothly is difficult at times.We investigated performance (response time) of stop-and-restart movements using a go/stop/re-go task and found consistent stop-and-restart difficulties after short (~100 ms) stop-to-restart intervals (SRSI), and an increased probability of difficulties after longer (>200 ms) SRSIs, suggesting that two different mechanisms underlie stop-and-restart difficulties.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Human Life Sciences, Showa Women's University, Tokyo, Japan.

ABSTRACT
The ability to suddenly stop a planned movement or a movement being performed and restart it after a short interval is an important mechanism that allows appropriate behavior in response to contextual or environmental changes. However, performing such stop-and-restart movements smoothly is difficult at times. We investigated performance (response time) of stop-and-restart movements using a go/stop/re-go task and found consistent stop-and-restart difficulties after short (~100 ms) stop-to-restart intervals (SRSI), and an increased probability of difficulties after longer (>200 ms) SRSIs, suggesting that two different mechanisms underlie stop-and-restart difficulties. Next, we investigated motor evoked potentials (MEPs) in a moving muscle induced by transcranial magnetic stimulation during a go/stop/re-go task. In re-go trials with a short SRSI (100 ms), the MEP amplitude continued to decrease after the re-go-signal onset, indicating that stop-and-restart difficulties with short SRSIs might be associated with a neural mechanism in the human motor system, namely, stop-related suppression of corticomotor (CM) excitability. Finally, we recorded electroencephalogram (EEG) activity during a go/stop/re-go task and performed a single-trial-based EEG power and phase time-frequency analysis. Alpha-band EEG phase locking to re-go-signal, which was only observed in re-go trials with long SRSI (250 ms), weakened in the delayed re-go response trials. These EEG phase dynamics indicate an association between stop-and-restart difficulties with long SRSIs and a neural mechanism in the human perception system, namely, decreased probability of EEG phase locking to visual stimuli. In contrast, smooth stop-and-restart human movement can be achieved in re-go trials with sufficient SRSI (150-200 ms), because release of stop-related suppression and simultaneous counter-activation of CM excitability may occur as a single task without second re-go-signal perception. These results suggest that skilled motor behavior is subject to various constraints in not only motor, but also perceptual (and attentional), systems.

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Task designs of the three experiments.(A) Illustrations of display and trial structure for the simple reaction time (SRT), go/stop, and go/stop/re-go tasks in Experiment 1. The trial type is noted on the right, and the total number of trials is shown in brackets. Time scale is displayed at the bottom. Vertical lines at −1000 ms represent indicator onset, vertical dashed lines at 0 ms represent the target, and vertical dotted lines represent feedback onset. In stop and re-go trials, the time points at which the indicator stopped are shown with vertical thin bars. In SRT task and re-go trials, time points at which the indicator (re-) started are shown with vertical thick bars. Small numbers between stop and restart bars in re-go trials indicate stop-to-restart intervals (SRSIs) in milliseconds. (B) Illustrations of trial structure for the go/stop and go/stop/re-go tasks in Experiment 2. Small triangles represent time points at which transcranial magnetic stimulation was delivered (TMS time). (C) Illustration of trial structure for the go/stop/re-go task in Experiment 3.
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pone-0082272-g001: Task designs of the three experiments.(A) Illustrations of display and trial structure for the simple reaction time (SRT), go/stop, and go/stop/re-go tasks in Experiment 1. The trial type is noted on the right, and the total number of trials is shown in brackets. Time scale is displayed at the bottom. Vertical lines at −1000 ms represent indicator onset, vertical dashed lines at 0 ms represent the target, and vertical dotted lines represent feedback onset. In stop and re-go trials, the time points at which the indicator stopped are shown with vertical thin bars. In SRT task and re-go trials, time points at which the indicator (re-) started are shown with vertical thick bars. Small numbers between stop and restart bars in re-go trials indicate stop-to-restart intervals (SRSIs) in milliseconds. (B) Illustrations of trial structure for the go/stop and go/stop/re-go tasks in Experiment 2. Small triangles represent time points at which transcranial magnetic stimulation was delivered (TMS time). (C) Illustration of trial structure for the go/stop/re-go task in Experiment 3.

Mentions: In the SRT task (Figure 1A, top), each trial began with the presentation of a white bar against a gray background. A red indicator was presented at 8/14 of the height of the white bar at the beginning of the trial. After a variable delay of 900, 1000, 1100, or 1200 ms, the red indicator turned green and moved upward at a constant rate, reaching the top of the bar in 600 ms. Participants were instructed to click the mouse to stop the indicator as fast as possible immediately after the indicator began moving. All participants performed two blocks of 50 trials. There were 100 SRT task trials in total.


Neural mechanisms underlying stop-and-restart difficulties: involvement of the motor and perceptual systems.

Yamanaka K, Nozaki D - PLoS ONE (2013)

Task designs of the three experiments.(A) Illustrations of display and trial structure for the simple reaction time (SRT), go/stop, and go/stop/re-go tasks in Experiment 1. The trial type is noted on the right, and the total number of trials is shown in brackets. Time scale is displayed at the bottom. Vertical lines at −1000 ms represent indicator onset, vertical dashed lines at 0 ms represent the target, and vertical dotted lines represent feedback onset. In stop and re-go trials, the time points at which the indicator stopped are shown with vertical thin bars. In SRT task and re-go trials, time points at which the indicator (re-) started are shown with vertical thick bars. Small numbers between stop and restart bars in re-go trials indicate stop-to-restart intervals (SRSIs) in milliseconds. (B) Illustrations of trial structure for the go/stop and go/stop/re-go tasks in Experiment 2. Small triangles represent time points at which transcranial magnetic stimulation was delivered (TMS time). (C) Illustration of trial structure for the go/stop/re-go task in Experiment 3.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC3842301&req=5

pone-0082272-g001: Task designs of the three experiments.(A) Illustrations of display and trial structure for the simple reaction time (SRT), go/stop, and go/stop/re-go tasks in Experiment 1. The trial type is noted on the right, and the total number of trials is shown in brackets. Time scale is displayed at the bottom. Vertical lines at −1000 ms represent indicator onset, vertical dashed lines at 0 ms represent the target, and vertical dotted lines represent feedback onset. In stop and re-go trials, the time points at which the indicator stopped are shown with vertical thin bars. In SRT task and re-go trials, time points at which the indicator (re-) started are shown with vertical thick bars. Small numbers between stop and restart bars in re-go trials indicate stop-to-restart intervals (SRSIs) in milliseconds. (B) Illustrations of trial structure for the go/stop and go/stop/re-go tasks in Experiment 2. Small triangles represent time points at which transcranial magnetic stimulation was delivered (TMS time). (C) Illustration of trial structure for the go/stop/re-go task in Experiment 3.
Mentions: In the SRT task (Figure 1A, top), each trial began with the presentation of a white bar against a gray background. A red indicator was presented at 8/14 of the height of the white bar at the beginning of the trial. After a variable delay of 900, 1000, 1100, or 1200 ms, the red indicator turned green and moved upward at a constant rate, reaching the top of the bar in 600 ms. Participants were instructed to click the mouse to stop the indicator as fast as possible immediately after the indicator began moving. All participants performed two blocks of 50 trials. There were 100 SRT task trials in total.

Bottom Line: The ability to suddenly stop a planned movement or a movement being performed and restart it after a short interval is an important mechanism that allows appropriate behavior in response to contextual or environmental changes.However, performing such stop-and-restart movements smoothly is difficult at times.We investigated performance (response time) of stop-and-restart movements using a go/stop/re-go task and found consistent stop-and-restart difficulties after short (~100 ms) stop-to-restart intervals (SRSI), and an increased probability of difficulties after longer (>200 ms) SRSIs, suggesting that two different mechanisms underlie stop-and-restart difficulties.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Human Life Sciences, Showa Women's University, Tokyo, Japan.

ABSTRACT
The ability to suddenly stop a planned movement or a movement being performed and restart it after a short interval is an important mechanism that allows appropriate behavior in response to contextual or environmental changes. However, performing such stop-and-restart movements smoothly is difficult at times. We investigated performance (response time) of stop-and-restart movements using a go/stop/re-go task and found consistent stop-and-restart difficulties after short (~100 ms) stop-to-restart intervals (SRSI), and an increased probability of difficulties after longer (>200 ms) SRSIs, suggesting that two different mechanisms underlie stop-and-restart difficulties. Next, we investigated motor evoked potentials (MEPs) in a moving muscle induced by transcranial magnetic stimulation during a go/stop/re-go task. In re-go trials with a short SRSI (100 ms), the MEP amplitude continued to decrease after the re-go-signal onset, indicating that stop-and-restart difficulties with short SRSIs might be associated with a neural mechanism in the human motor system, namely, stop-related suppression of corticomotor (CM) excitability. Finally, we recorded electroencephalogram (EEG) activity during a go/stop/re-go task and performed a single-trial-based EEG power and phase time-frequency analysis. Alpha-band EEG phase locking to re-go-signal, which was only observed in re-go trials with long SRSI (250 ms), weakened in the delayed re-go response trials. These EEG phase dynamics indicate an association between stop-and-restart difficulties with long SRSIs and a neural mechanism in the human perception system, namely, decreased probability of EEG phase locking to visual stimuli. In contrast, smooth stop-and-restart human movement can be achieved in re-go trials with sufficient SRSI (150-200 ms), because release of stop-related suppression and simultaneous counter-activation of CM excitability may occur as a single task without second re-go-signal perception. These results suggest that skilled motor behavior is subject to various constraints in not only motor, but also perceptual (and attentional), systems.

Show MeSH
Related in: MedlinePlus