No effect of delay on the spatial representation of serial reach targets
No effect of delay on the spatial representation of serial reach targets
复制标题
延迟对连续到达目标的空间表示没有影响
作者：
I. Schütz;D. Henriques;K. Fiehler
当到达记忆中的目标位置时，有人认为大脑主要依赖于以自我为中心的指标，特别是当到达是即时的时，目标相对于凝视的位置，但当到达是延迟的时，视觉运动系统更依赖于非中心（即以物体为中心）的指标。然而，我们小组之前的报告表明，到达单个记忆目标的距离是相对于凝视而言的，即使在静态视觉地标可用且到达延迟长达12秒的情况下也是如此。基于先前的研究发现，异心编码在连续到达计划中有更强的贡献，本研究旨在确定延迟是否会影响在延迟0、5或12秒后到达序列中两个记忆目标时注视依赖参考框架的使用。目光相对于第一个和第二个目标是不同的，并且在每次到达目标之前都会从目标移开。我们发现，无论即时执行还是延迟执行，参与者都更依赖于非中心信息，同时使用自我中心和非中心参考框架。我们的研究结果表明，自我中心和非中心参考框架对空间编码和顺序到达目标更新的相对贡献不随目标呈现和到达之间的记忆延迟而改变。
When reaching for remembered target locations, it has been argued that the brain primarily relies on egocentric metrics and especially target position relative to gaze when reaches are immediate, but that the visuo-motor system relies stronger on allocentric (i.e., object-centered) metrics when a reach is delayed. However, previous reports from our group have shown that reaches to single remembered targets are represented relative to gaze, even when static visual landmarks are available and reaches are delayed by up to 12 s. Based on previous findings which showed a stronger contribution of allocentric coding in serial reach planning, the present study aimed to determine whether delay influences the use of a gaze-dependent reference frame when reaching to two remembered targets in a sequence after a delay of 0, 5 or 12 s. Gaze was varied relative to the first and second target and shifted away from the target before each reach. We found that participants used egocentric and allocentric reference frames in combination with a stronger reliance on allocentric information regardless of whether reaches were executed immediately or after a delay. Our results suggest that the relative contributions of egocentric and allocentric reference frames for spatial coding and updating of sequential reach targets do not change with a memory delay between target presentation and reaching.
影响因子：
1.8
作者：
Hesse, Constanze;Franz, Volker H.
通讯作者：
Franz, Volker H.
影响因子：
13.9
作者：
Systems J F Soechting;M. Flanders
通讯作者：
Systems J F Soechting;M. Flanders
指向一个非中心和自我中心的记忆目标。
影响因子：
1.1
作者：
Lemay,Martin;Bertram,ChristopherP;Stelmach,GeorgeE
通讯作者：
Stelmach,GeorgeE