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Common neural correlates of real and imagined movements contributing to the performance of brain-machine interfaces.

Sugata H, Hirata M, Yanagisawa T, Matsushita K, Yorifuji S, Yoshimine T - Sci Rep (2016)

Bottom Line: Similarly, although decoding accuracies surpassed the chance level in both real and imagined movements, these were significantly different after the onset.The temporal correlation of decoding accuracy significantly increased around the hand and arm areas, except for the period immediately after response onset.Our results suggest that cM1 is involved in similar neural activities related to the representation of motor information during real and imagined movements, except for presence or absence of sensory-motor integration induced by sensory feedback.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosurgery, Osaka University Medical School, 2-2 Yamadaoka, Osaka, 565-0871, Japan.

ABSTRACT
The relationship between M1 activity representing motor information in real and imagined movements have not been investigated with high spatiotemporal resolution using non-invasive measurements. We examined the similarities and differences in M1 activity during real and imagined movements. Ten subjects performed or imagined three types of right upper limb movements. To infer the movement type, we used 40 virtual channels in the M1 contralateral to the movement side (cM1) using a beamforming approach. For both real and imagined movements, cM1 activities increased around response onset, after which their intensities were significantly different. Similarly, although decoding accuracies surpassed the chance level in both real and imagined movements, these were significantly different after the onset. Single virtual channel-based analysis showed that decoding accuracy significantly increased around the hand and arm areas during real and imagined movements and that these are spatially correlated. The temporal correlation of decoding accuracy significantly increased around the hand and arm areas, except for the period immediately after response onset. Our results suggest that cM1 is involved in similar neural activities related to the representation of motor information during real and imagined movements, except for presence or absence of sensory-motor integration induced by sensory feedback.

No MeSH data available.


Related in: MedlinePlus

Intensity of cM1 activity and decoding accuracy during real and imagined movements.(A) cM1 activity sharply peaked at 200 ms in the real movement, whereas only small peaks were observed at 150 and 250 ms in the imagined movement. A significant difference in the intensity of cM1 activity between real and imagined movements was observed at 200 ms (Mann–Whitney U-test, *p < 0.01) (error bar, standard error). (B) In the real movement, decoding accuracy gradually increased before response onset and peaked at 100 ms (error bar, SD). Decoding accuracy was plotted for the first sample acquired in the time window. The two horizontal solid and dotted lines indicate decoding accuracy at the chance level (33.3%; binomial test, p = 0.01 for both). (C) In the imagined movement, decoding accuracy showed two peaks at 50 and 300 ms (binomial test, p < 0.01). (D) Significant differences in decoding accuracy between real and imagined movements were observed at 200 ms (Mann–Whitney U-test, p < 0.05).
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f2: Intensity of cM1 activity and decoding accuracy during real and imagined movements.(A) cM1 activity sharply peaked at 200 ms in the real movement, whereas only small peaks were observed at 150 and 250 ms in the imagined movement. A significant difference in the intensity of cM1 activity between real and imagined movements was observed at 200 ms (Mann–Whitney U-test, *p < 0.01) (error bar, standard error). (B) In the real movement, decoding accuracy gradually increased before response onset and peaked at 100 ms (error bar, SD). Decoding accuracy was plotted for the first sample acquired in the time window. The two horizontal solid and dotted lines indicate decoding accuracy at the chance level (33.3%; binomial test, p = 0.01 for both). (C) In the imagined movement, decoding accuracy showed two peaks at 50 and 300 ms (binomial test, p < 0.01). (D) Significant differences in decoding accuracy between real and imagined movements were observed at 200 ms (Mann–Whitney U-test, p < 0.05).

Mentions: Figure 2A shows the time courses of brain activities in M1 contralateral to the movement side (cM1) during real and imagined movements. For real movements, the intensity of cM1 activity gradually increased from −500 ms and sharply peaked at 200 ms, whereas no such clear peak was observed for the imagined movement. Instead, two small peaks were observed at 150 and 250 ms. A significant difference in the intensity of cM1 activity between real and imagined movements was observed at 200 ms (Mann–Whitney U-test, p < 0.01) (Fig. 2A). To compare cM1 activity with other brain regions, the intensities of brain activity were also calculated from the following seven regions of interest (ROIs); contralateral S1 (cS1), frontal (c-frontal), and parietal (c-parietal) areas; ipsilateral M1 (iM1), S1 (iS1), frontal (i-frontal), and parietal (i-parietal) areas. However, there were no significant differences between the real and imagined movements in these brain regions (Fig. S2).


Common neural correlates of real and imagined movements contributing to the performance of brain-machine interfaces.

Sugata H, Hirata M, Yanagisawa T, Matsushita K, Yorifuji S, Yoshimine T - Sci Rep (2016)

Intensity of cM1 activity and decoding accuracy during real and imagined movements.(A) cM1 activity sharply peaked at 200 ms in the real movement, whereas only small peaks were observed at 150 and 250 ms in the imagined movement. A significant difference in the intensity of cM1 activity between real and imagined movements was observed at 200 ms (Mann–Whitney U-test, *p < 0.01) (error bar, standard error). (B) In the real movement, decoding accuracy gradually increased before response onset and peaked at 100 ms (error bar, SD). Decoding accuracy was plotted for the first sample acquired in the time window. The two horizontal solid and dotted lines indicate decoding accuracy at the chance level (33.3%; binomial test, p = 0.01 for both). (C) In the imagined movement, decoding accuracy showed two peaks at 50 and 300 ms (binomial test, p < 0.01). (D) Significant differences in decoding accuracy between real and imagined movements were observed at 200 ms (Mann–Whitney U-test, p < 0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4835797&req=5

f2: Intensity of cM1 activity and decoding accuracy during real and imagined movements.(A) cM1 activity sharply peaked at 200 ms in the real movement, whereas only small peaks were observed at 150 and 250 ms in the imagined movement. A significant difference in the intensity of cM1 activity between real and imagined movements was observed at 200 ms (Mann–Whitney U-test, *p < 0.01) (error bar, standard error). (B) In the real movement, decoding accuracy gradually increased before response onset and peaked at 100 ms (error bar, SD). Decoding accuracy was plotted for the first sample acquired in the time window. The two horizontal solid and dotted lines indicate decoding accuracy at the chance level (33.3%; binomial test, p = 0.01 for both). (C) In the imagined movement, decoding accuracy showed two peaks at 50 and 300 ms (binomial test, p < 0.01). (D) Significant differences in decoding accuracy between real and imagined movements were observed at 200 ms (Mann–Whitney U-test, p < 0.05).
Mentions: Figure 2A shows the time courses of brain activities in M1 contralateral to the movement side (cM1) during real and imagined movements. For real movements, the intensity of cM1 activity gradually increased from −500 ms and sharply peaked at 200 ms, whereas no such clear peak was observed for the imagined movement. Instead, two small peaks were observed at 150 and 250 ms. A significant difference in the intensity of cM1 activity between real and imagined movements was observed at 200 ms (Mann–Whitney U-test, p < 0.01) (Fig. 2A). To compare cM1 activity with other brain regions, the intensities of brain activity were also calculated from the following seven regions of interest (ROIs); contralateral S1 (cS1), frontal (c-frontal), and parietal (c-parietal) areas; ipsilateral M1 (iM1), S1 (iS1), frontal (i-frontal), and parietal (i-parietal) areas. However, there were no significant differences between the real and imagined movements in these brain regions (Fig. S2).

Bottom Line: Similarly, although decoding accuracies surpassed the chance level in both real and imagined movements, these were significantly different after the onset.The temporal correlation of decoding accuracy significantly increased around the hand and arm areas, except for the period immediately after response onset.Our results suggest that cM1 is involved in similar neural activities related to the representation of motor information during real and imagined movements, except for presence or absence of sensory-motor integration induced by sensory feedback.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosurgery, Osaka University Medical School, 2-2 Yamadaoka, Osaka, 565-0871, Japan.

ABSTRACT
The relationship between M1 activity representing motor information in real and imagined movements have not been investigated with high spatiotemporal resolution using non-invasive measurements. We examined the similarities and differences in M1 activity during real and imagined movements. Ten subjects performed or imagined three types of right upper limb movements. To infer the movement type, we used 40 virtual channels in the M1 contralateral to the movement side (cM1) using a beamforming approach. For both real and imagined movements, cM1 activities increased around response onset, after which their intensities were significantly different. Similarly, although decoding accuracies surpassed the chance level in both real and imagined movements, these were significantly different after the onset. Single virtual channel-based analysis showed that decoding accuracy significantly increased around the hand and arm areas during real and imagined movements and that these are spatially correlated. The temporal correlation of decoding accuracy significantly increased around the hand and arm areas, except for the period immediately after response onset. Our results suggest that cM1 is involved in similar neural activities related to the representation of motor information during real and imagined movements, except for presence or absence of sensory-motor integration induced by sensory feedback.

No MeSH data available.


Related in: MedlinePlus