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Cerebral Spectral Perturbation during Upper Limb Diagonal Movements
DOI: http://dx.doi.org/10.5772/intechopen.88337
3.1.2.4 Alpha1 vs. Alpha2
Since lower and upper alphas have previously been reported to have different
roles, lower alpha being related to general attentional processes and upper alpha
being more sensitive to perceptual and semantic processing during task performance [51], we further wanted to explore the possibility that lower and upper
alpha could have different involvement in the modulation of alpha biphasic activity
during vertical movements. Therefore, we analyzed POz, where we have found the
maximum alpha modulation.
We divided the alpha band into Alpha1 and Alpha2 (8–10 Hz and 11–12 Hz,
respectively) and performed a two-way ANOVA with alpha (Alpha1, Alpha2) and
peak (Peak1, Peak2) as factors.
The main effect of peak was significant [F(1, 10) = 11.42; p < 0.01; η2 = 0.53],
suggesting that Peak2 (mean, 0.432 dB) was significantly higher than Peak1 (mean.
−0.689 dB). The alpha-peak interaction was significant [F(1, 10) = 14.5; p < 0.01;
η2 = 0.59]. Fisher LSD post hoc revealed that comparison between Alpha1 and
Alpha2 approached significance in Peak1 (p = 0.07) and was significant in Peak2
(p < 0.05) (see Figure 8).
3.1.3 Beta (13–30 Hz)
For analysis in the beta frequency, we used the same time window already
used for the alpha band. In forward period (M1), we therefore used four consecutive time windows lasting 250 ms each, while in the comeback period, we used
three time windows: p1 = 200–400 ms, p2 = 400–700 ms, p3 = 700–900 ms (see
Figure 9).
3.1.3.1 Beta: forward period
A 2 × 4 ANOVA using condition (vertical, diagonal) and time window (t1, t2,
t3, t4) as factors was conducted. We performed analysis on the frontal and parietal
ROIs. For the frontal ROI, none of the main effects or interaction were significant (all
p > 0.25). For the parietal ROI, none of the main effects were significant (all p > 0.38).
Figure 8.
Comparisons between Alpha1 and Alpha2 in Peak1 and Peak2. The bold line represents a significant difference
(p < 0.05), and the dashed line represents a difference that approaches statistical significance.
Cerebral Spectral Perturbation during Upper Limb Diagonal Movements
DOI: http://dx.doi.org/10.5772/intechopen.88337
3.1.2.4 Alpha1 vs. Alpha2
Since lower and upper alphas have previously been reported to have different
roles, lower alpha being related to general attentional processes and upper alpha
being more sensitive to perceptual and semantic processing during task performance [51], we further wanted to explore the possibility that lower and upper
alpha could have different involvement in the modulation of alpha biphasic activity
during vertical movements. Therefore, we analyzed POz, where we have found the
maximum alpha modulation.
We divided the alpha band into Alpha1 and Alpha2 (8–10 Hz and 11–12 Hz,
respectively) and performed a two-way ANOVA with alpha (Alpha1, Alpha2) and
peak (Peak1, Peak2) as factors.
The main effect of peak was significant [F(1, 10) = 11.42; p < 0.01; η2 = 0.53],
suggesting that Peak2 (mean, 0.432 dB) was significantly higher than Peak1 (mean.
−0.689 dB). The alpha-peak interaction was significant [F(1, 10) = 14.5; p < 0.01;
η2 = 0.59]. Fisher LSD post hoc revealed that comparison between Alpha1 and
Alpha2 approached significance in Peak1 (p = 0.07) and was significant in Peak2
(p < 0.05) (see Figure 8).
3.1.3 Beta (13–30 Hz)
For analysis in the beta frequency, we used the same time window already
used for the alpha band. In forward period (M1), we therefore used four consecutive time windows lasting 250 ms each, while in the comeback period, we used
three time windows: p1 = 200–400 ms, p2 = 400–700 ms, p3 = 700–900 ms (see
Figure 9).
3.1.3.1 Beta: forward period
A 2 × 4 ANOVA using condition (vertical, diagonal) and time window (t1, t2,
t3, t4) as factors was conducted. We performed analysis on the frontal and parietal
ROIs. For the frontal ROI, none of the main effects or interaction were significant (all
p > 0.25). For the parietal ROI, none of the main effects were significant (all p > 0.38).
Figure 8.
Comparisons between Alpha1 and Alpha2 in Peak1 and Peak2. The bold line represents a significant difference
(p < 0.05), and the dashed line represents a difference that approaches statistical significance.