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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

Task paradigm and location of virtual channels.(A) Experimental paradigm. Subjects performed the motion and imagined tasks in the same sequence. The trial consisted of four phases; the rest phase, instruction phase, preparation phase, and execution phase. In the rest phase, a black fixation cross “+” was presented for 4 s. Subjects fixed their eyes on the cross. In the instruction phase, a Japanese word representing one of three movements was presented for 1 s. Then, in the preparation phase, two timing cues, “> <” and “> <,” were presented one at a time, each for 1 s to aid the subjects in preparing for the execution of real or imagined movements. In the execution phase, subjects performed the real or imagined movement, as requested in the instruction phase stage, after the appearance of the execution cue “×.” Each of the three movements was performed 60 times. (B) Locations of the virtual channels are indicated by white dots on a three-dimensional brain model. Forty virtual channels were located on the left cM1 at intervals of 2.5 mm. The black dotted line indicates the location of the central sulcus. A, anterior; L, lateral; M, medial; P, posterior.
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f6: Task paradigm and location of virtual channels.(A) Experimental paradigm. Subjects performed the motion and imagined tasks in the same sequence. The trial consisted of four phases; the rest phase, instruction phase, preparation phase, and execution phase. In the rest phase, a black fixation cross “+” was presented for 4 s. Subjects fixed their eyes on the cross. In the instruction phase, a Japanese word representing one of three movements was presented for 1 s. Then, in the preparation phase, two timing cues, “> <” and “> <,” were presented one at a time, each for 1 s to aid the subjects in preparing for the execution of real or imagined movements. In the execution phase, subjects performed the real or imagined movement, as requested in the instruction phase stage, after the appearance of the execution cue “×.” Each of the three movements was performed 60 times. (B) Locations of the virtual channels are indicated by white dots on a three-dimensional brain model. Forty virtual channels were located on the left cM1 at intervals of 2.5 mm. The black dotted line indicates the location of the central sulcus. A, anterior; L, lateral; M, medial; P, posterior.

Mentions: The temporal correlation of decoding accuracy between real and imagined movements was also examined in each virtual channel. Figure 5 shows temporal correlations of particular time ranges of decoding accuracy in cM1 between real and imagined movements. The temporal correlation significantly increased from −200 ms (−450–50 ms) around the medial part of cM1, including the hand and arm areas [Spearman’s rank correlation test, p < 0.05, false discovery rate (FDR)-corrected] (Fig. 5, also see Fig. 6B). Although this significant correlation disappeared around response onset, it reappeared from 400 ms (150–650 ms) (Fig. 5 and Supplementary movie 5). Temporal correlations were also calculated in the other seven ROIs. The results showed a significant correlation between cS1 before and after response onset but not from 100 to 300 ms, which was weaker than that in cM1 (Fig. S9) (Spearman’s rank correlation test, p < 0.05, FDR-corrected). These significant correlations tended to cluster around the hand and arm areas. The remaining six ROIs showed no significant temporal correlation.


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)

Task paradigm and location of virtual channels.(A) Experimental paradigm. Subjects performed the motion and imagined tasks in the same sequence. The trial consisted of four phases; the rest phase, instruction phase, preparation phase, and execution phase. In the rest phase, a black fixation cross “+” was presented for 4 s. Subjects fixed their eyes on the cross. In the instruction phase, a Japanese word representing one of three movements was presented for 1 s. Then, in the preparation phase, two timing cues, “> <” and “> <,” were presented one at a time, each for 1 s to aid the subjects in preparing for the execution of real or imagined movements. In the execution phase, subjects performed the real or imagined movement, as requested in the instruction phase stage, after the appearance of the execution cue “×.” Each of the three movements was performed 60 times. (B) Locations of the virtual channels are indicated by white dots on a three-dimensional brain model. Forty virtual channels were located on the left cM1 at intervals of 2.5 mm. The black dotted line indicates the location of the central sulcus. A, anterior; L, lateral; M, medial; P, posterior.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835797&req=5

f6: Task paradigm and location of virtual channels.(A) Experimental paradigm. Subjects performed the motion and imagined tasks in the same sequence. The trial consisted of four phases; the rest phase, instruction phase, preparation phase, and execution phase. In the rest phase, a black fixation cross “+” was presented for 4 s. Subjects fixed their eyes on the cross. In the instruction phase, a Japanese word representing one of three movements was presented for 1 s. Then, in the preparation phase, two timing cues, “> <” and “> <,” were presented one at a time, each for 1 s to aid the subjects in preparing for the execution of real or imagined movements. In the execution phase, subjects performed the real or imagined movement, as requested in the instruction phase stage, after the appearance of the execution cue “×.” Each of the three movements was performed 60 times. (B) Locations of the virtual channels are indicated by white dots on a three-dimensional brain model. Forty virtual channels were located on the left cM1 at intervals of 2.5 mm. The black dotted line indicates the location of the central sulcus. A, anterior; L, lateral; M, medial; P, posterior.
Mentions: The temporal correlation of decoding accuracy between real and imagined movements was also examined in each virtual channel. Figure 5 shows temporal correlations of particular time ranges of decoding accuracy in cM1 between real and imagined movements. The temporal correlation significantly increased from −200 ms (−450–50 ms) around the medial part of cM1, including the hand and arm areas [Spearman’s rank correlation test, p < 0.05, false discovery rate (FDR)-corrected] (Fig. 5, also see Fig. 6B). Although this significant correlation disappeared around response onset, it reappeared from 400 ms (150–650 ms) (Fig. 5 and Supplementary movie 5). Temporal correlations were also calculated in the other seven ROIs. The results showed a significant correlation between cS1 before and after response onset but not from 100 to 300 ms, which was weaker than that in cM1 (Fig. S9) (Spearman’s rank correlation test, p < 0.05, FDR-corrected). These significant correlations tended to cluster around the hand and arm areas. The remaining six ROIs showed no significant temporal correlation.

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