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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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Results of phase locking index analysis in Experiment 3.(A) Time/frequency (T/F) images of grand mean phase locking index (PLI) obtained during go trials, stop trials, re-go trials with an SRSI of 150 ms (re-go(150)), and re-go trials with an SRSI of 250 ms (re-go(250)). The T/F images are shown only at Fz, Cz, Pz, and O2. Vertical thin lines represent stop-signal onset, vertical dashed lines represent target time for the primary go trials, and vertical thick lines represent re-go-signal onset. Time scale is displayed at the bottom. (B) Scalp topographies of grand mean PLI in go, stop, re-go(150), and re-go(250) trials. They are displayed at time/frequency points described in the figure. (C) T/F images indicating the results of the PLI statistical test (re-go(150) vs. stop and re-go(250) vs. stop). The T/F images are only shown at Fz, Cz, Pz, and O2. The yellow and blue parts of the T/F images represent significant differences (p<.05; paired t-test), and the red and blue parts of the T/F images represent significant differences after correction for multiple comparisons (p<.05; paired t-test with FDR control; q*<.05). (D) Scalp topographies of grand mean PLI differences (re-go(150) – stop and re-go(250) – stop). They are displayed only at some time/frequency points described in the figure.
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pone-0082272-g005: Results of phase locking index analysis in Experiment 3.(A) Time/frequency (T/F) images of grand mean phase locking index (PLI) obtained during go trials, stop trials, re-go trials with an SRSI of 150 ms (re-go(150)), and re-go trials with an SRSI of 250 ms (re-go(250)). The T/F images are shown only at Fz, Cz, Pz, and O2. Vertical thin lines represent stop-signal onset, vertical dashed lines represent target time for the primary go trials, and vertical thick lines represent re-go-signal onset. Time scale is displayed at the bottom. (B) Scalp topographies of grand mean PLI in go, stop, re-go(150), and re-go(250) trials. They are displayed at time/frequency points described in the figure. (C) T/F images indicating the results of the PLI statistical test (re-go(150) vs. stop and re-go(250) vs. stop). The T/F images are only shown at Fz, Cz, Pz, and O2. The yellow and blue parts of the T/F images represent significant differences (p<.05; paired t-test), and the red and blue parts of the T/F images represent significant differences after correction for multiple comparisons (p<.05; paired t-test with FDR control; q*<.05). (D) Scalp topographies of grand mean PLI differences (re-go(150) – stop and re-go(250) – stop). They are displayed only at some time/frequency points described in the figure.

Mentions: When we compared grand mean PLI T/F images in go, stop, re-go(150), and re-go(250) trials, identical transient theta-to-alpha-band PLI increases were observed over the frontocentral areas around 0 ms (corresponding to 200 ms after stop-signal onset), in stop and both re-go conditions (Figure 5A, B), indicating the existence of stop-related EEG phase locking across trials. In addition, we observed a second transient theta-to-alpha-band PLI increase over the parieto-occipital sites during about 200–300 ms (corresponding to 150–250 ms after re-go-signal onset) only in re-go(250) trials (Figure 5B, D). Consequently, the theta-to-alpha-band PLI values at O2 in re-go(250) trials were significantly larger than those in stop trials during about 200–300 ms (p<.05 with FDR control; q*<.05), which corresponds to about 150–250 ms after re-go-signal onset, while there was no large cluster with significant PLI differences between stop and re-go(150) trials (Figure 5C).


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

Yamanaka K, Nozaki D - PLoS ONE (2013)

Results of phase locking index analysis in Experiment 3.(A) Time/frequency (T/F) images of grand mean phase locking index (PLI) obtained during go trials, stop trials, re-go trials with an SRSI of 150 ms (re-go(150)), and re-go trials with an SRSI of 250 ms (re-go(250)). The T/F images are shown only at Fz, Cz, Pz, and O2. Vertical thin lines represent stop-signal onset, vertical dashed lines represent target time for the primary go trials, and vertical thick lines represent re-go-signal onset. Time scale is displayed at the bottom. (B) Scalp topographies of grand mean PLI in go, stop, re-go(150), and re-go(250) trials. They are displayed at time/frequency points described in the figure. (C) T/F images indicating the results of the PLI statistical test (re-go(150) vs. stop and re-go(250) vs. stop). The T/F images are only shown at Fz, Cz, Pz, and O2. The yellow and blue parts of the T/F images represent significant differences (p<.05; paired t-test), and the red and blue parts of the T/F images represent significant differences after correction for multiple comparisons (p<.05; paired t-test with FDR control; q*<.05). (D) Scalp topographies of grand mean PLI differences (re-go(150) – stop and re-go(250) – stop). They are displayed only at some time/frequency points described in the figure.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3842301&req=5

pone-0082272-g005: Results of phase locking index analysis in Experiment 3.(A) Time/frequency (T/F) images of grand mean phase locking index (PLI) obtained during go trials, stop trials, re-go trials with an SRSI of 150 ms (re-go(150)), and re-go trials with an SRSI of 250 ms (re-go(250)). The T/F images are shown only at Fz, Cz, Pz, and O2. Vertical thin lines represent stop-signal onset, vertical dashed lines represent target time for the primary go trials, and vertical thick lines represent re-go-signal onset. Time scale is displayed at the bottom. (B) Scalp topographies of grand mean PLI in go, stop, re-go(150), and re-go(250) trials. They are displayed at time/frequency points described in the figure. (C) T/F images indicating the results of the PLI statistical test (re-go(150) vs. stop and re-go(250) vs. stop). The T/F images are only shown at Fz, Cz, Pz, and O2. The yellow and blue parts of the T/F images represent significant differences (p<.05; paired t-test), and the red and blue parts of the T/F images represent significant differences after correction for multiple comparisons (p<.05; paired t-test with FDR control; q*<.05). (D) Scalp topographies of grand mean PLI differences (re-go(150) – stop and re-go(250) – stop). They are displayed only at some time/frequency points described in the figure.
Mentions: When we compared grand mean PLI T/F images in go, stop, re-go(150), and re-go(250) trials, identical transient theta-to-alpha-band PLI increases were observed over the frontocentral areas around 0 ms (corresponding to 200 ms after stop-signal onset), in stop and both re-go conditions (Figure 5A, B), indicating the existence of stop-related EEG phase locking across trials. In addition, we observed a second transient theta-to-alpha-band PLI increase over the parieto-occipital sites during about 200–300 ms (corresponding to 150–250 ms after re-go-signal onset) only in re-go(250) trials (Figure 5B, D). Consequently, the theta-to-alpha-band PLI values at O2 in re-go(250) trials were significantly larger than those in stop trials during about 200–300 ms (p<.05 with FDR control; q*<.05), which corresponds to about 150–250 ms after re-go-signal onset, while there was no large cluster with significant PLI differences between stop and re-go(150) trials (Figure 5C).

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