Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de Mexico, Ciudad de México, Distrito Federal, Mexico.
Behav Brain Res. 2011 May 16;219(1):8-14. doi: 10.1016/j.bbr.2010.11.060. Epub 2010 Dec 5.
Adaptation of reaching movements to visuomotor transformations is generally thought to involve implicit or procedural learning. However, there is evidence that explicit or cognitive processes can also play a role (Redding and Wallace, 2006 [31]). For example, the early phase of adaptation to a visuomotor rotation appears to involve spatial working memory processes linked to mental rotation (Anguera et al., 2010 [11]). Since it is known that cognitive processes like mental rotation lead to larger reaction times (Georgopoulos and Massey, 1987 [12]), here we explored the relation between reaction time (RT) and reach error reduction. Two groups of subjects adapted their reaching movements to a 60° visuomotor rotation either without RT constraints or with RT limited to 350 ms. In the unconstrained group, we found that adaption rate varied widely across subjects and was strongly correlated with RT. Subjects who decreased hand direction error (DE) rapidly exhibited prolonged RTs whereas little RT cost was seen in subjects who decreased DE gradually. RTs were also correlated with after-effects seen when the visuomotor rotation was removed. Subjects with the longest RTs exhibited the smallest after-effects. In the RT constrained group, all subjects exhibited gradual DE adaptation and large after-effects, similar to the fast responders in the free group. These results suggest that adaptation to a visuomotor rotation can involve processes that produce faster error reductions without increasing after-effects, but at an expense of larger reaction times. Possible candidates are processes related to spatial working memory, and more specifically, to mental rotation.
适应视动转换的运动通常被认为涉及内隐或程序性学习。然而，有证据表明，外显或认知过程也可以发挥作用（Redding 和 Wallace，2006 [31]）。例如，适应视动旋转的早期阶段似乎涉及与心理旋转相关的空间工作记忆过程（Anguera 等人，2010 [11]）。由于众所周知，像心理旋转这样的认知过程会导致更长的反应时间（Georgopoulos 和 Massey，1987 [12]），因此，我们在这里探讨了反应时间（RT）和减少到达错误之间的关系。两组受试者在不受 RT 限制或 RT 限制为 350 ms 的情况下，适应其到达运动至 60°视动旋转。在不受限制的组中，我们发现适应率在受试者之间差异很大，并且与 RT 密切相关。快速减少手方向误差（DE）的受试者表现出延长的 RT，而逐渐减少 DE 的受试者则几乎没有 RT 成本。RT 还与去除视动旋转时出现的后效相关。RT 最长的受试者表现出最小的后效。在 RT 受限的组中，所有受试者都表现出逐渐的 DE 适应和较大的后效，类似于自由组中的快速响应者。这些结果表明，适应视动旋转可以涉及产生更快错误减少而不增加后效的过程，但代价是更大的反应时间。可能的候选者是与空间工作记忆相关的过程，更具体地说是与心理旋转相关的过程。
