Figure 5 : Mean and standard deviation of the interactions
between Condition and Time factors for in the ANOVAs on each component.
*p<0.5 **p>0.01
Figure 6 shows the results of the differential waves that highlight the
left parietal contribution in the reaching preparation and the bilateral
medial parieto-occipital contribution of the stepping preparation.
Figure 6a shows the scalp topography of the voltage distribution from a
posterior point of view in the -1500/0 ms interval of theReaching minus Keypress difference wave (left) and of theReaching-Stepping minus Reaching difference wave.
Figure 6b shows, for the same
difference wave and interval, the source reconstruction of those ERP
activities. Source analysis for
the Reaching minus Keypress difference show that the
activity was localized almost exclusively in the left hemisphere, which
is the hemisphere contralateral to the right arm/hand used to perform
the task. In addition, it suggests that this reaching-related activity
mainly originates latero-posteriorly (from the middle occipital gyrus,
the inferior occipital sulcus, the intraparietal-transverse occipital
gyrus, the inferior parietal lobule, IPL) and dorsally up to the
anterior precuneus but not medially. Source analysis for theReaching-Stepping minus Reaching difference show that the
activity was mainly bilateral and that the stepping-related activity
originates in the IPL and in the PPC, both medially and
dorsally up to the anterior
precuneus. In addition, ERP activity may originate also
latero-posteriorly from the middle occipital gyrus but mainly in the
right hemisphere.