Figure 5.
Interaction between information based on internal object representation and visual cues. Top, Schematic representation of the MEP amplitude for the four different lift conditions (a–d) and for each TMS timing (50, 100, or 150 ms) during movement preparation based on the data of Figure 2, B and C. At 50 ms, the ratios between conditions light-after-heavy and light-after-light (b/a) and between heavy-after-heavy and heavy-after-light (d/c) are above 1, meaning that b or d are greater than a or c, respectively. In contrast, ratios between heavy-after-light and light-after-light (c/a) and heavy-after-heavy and light-after-heavy (d/b) are close to 1, meaning that MEP amplitudes in these conditions are comparable. At 150 ms, instead, the b/a and d/c ratios are now close to 1 and the c/a and d/b ratios are above 1, meaning that, whatever the previous lift, visibly heavier objects have a larger MEP than lighter ones. Intermediate values are found at 100 ms. Bottom, Schematic evolution of the CSE during movement preparation depending on the previous lift and the upcoming visual cues. For example, if the previous object was light (black dotted line), CSE is low and remains low if the visual cues about the upcoming object are indicating a light weight (gray dotted line) or increases if cues are informative of a heavy object (gray solid line).