Department of Psychology, University of Muenster, Muenster, Germany.
Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany.
PLoS One. 2019 Jan 10;14(1):e0210020. doi: 10.1371/journal.pone.0210020. eCollection 2019.
Saccadic adaptation is assumed to be driven by an unconscious and automatic mechanism. We wondered if the adaptation process is accessible to volitional control, specifically whether any change in saccade gain can be inhibited. Participants were exposed to post-saccadic error by using the double-step paradigm in which a target is presented in a peripheral location and then stepped during the saccade to another location. In one condition, participants were instructed to follow the target step and look at the final target location. In the other condition they were instructed to inhibit the adjustment of saccade amplitude and look at the initial target location. We conducted two experiments, which differed in the size of the intra-saccadic target step. We found that when told to inhibit amplitude adjustment, gain change was close to zero for outward steps, but some adaptation remained for inward steps. Saccadic latency was not affected by the instruction type for inward steps, but when the target was stepped outward, latencies were longer in the inhibition than in the adaptation condition. The results show that volitional control can be exerted on saccadic adaptation. We suggest that volitional control affects the remapping of the target, thus having a larger impact on outward adaptation.
扫视适应被认为是由无意识和自动机制驱动的。我们想知道适应过程是否可以受到意志控制，特别是扫视增益是否可以被抑制。参与者通过使用双步范式来暴露于扫视后误差，其中目标出现在外围位置，然后在扫视期间移动到另一个位置。在一种情况下，参与者被指示跟随目标步并注视最终目标位置。在另一种情况下，他们被指示抑制扫视幅度的调整并注视初始目标位置。我们进行了两项实验，这些实验在扫视内目标步的大小上有所不同。我们发现，当被告知抑制幅度调整时，外向扫视的增益变化接近于零，但对于内向扫视仍有一些适应。对于内向扫视，指令类型对扫视潜伏期没有影响，但当目标向外移动时，抑制条件下的潜伏期比适应条件下的潜伏期长。结果表明，意志控制可以施加于扫视适应。我们认为，意志控制会影响目标的重新映射，因此对外向适应的影响更大。
