Saccadic adaptation and visual perception

• Applicant: Professor Dr. Markus Lappe
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 251576968

Final Report Abstract

We investigated various aspect of eye movement plasticity to deepen our understanding of saccadic adaptation, In the first series of experiments we circumscribes the differential influence of an intrinsically valuable image onto saccadic adaptation. We found that the time course at which the target image is evaluated is crucial to effect onto saccadic adaptation. Furthermore we found that images of humans, which could be described as primary reinforcers, lead to differences in saccadic adaptation, unlike short or longterm conditioned stimulus-value associations (words, short term conditioned stimuli, long term conditioned stimuli, monetary reward). In the second series of experiments we investigated the role of proprioceptive eye position information in the processes of saccadic adaptation. We showed that saccadic start position is available to the adaptation mechanism since the adaptation state of a saccade depended on its start position. In the second experiment in this section we manipulated the perceived eye position signal to investigate if this signal is used as a control signal for the accuracy of an eye movement. Since the change in perceived eye position did not lead to adjustments of the saccade vector, we did not find any evidence that this is the case. However, in the last experiment in this series we found that in the absence of visual feedback de-adaptation is stronger if proprioceptive eye position information is available after the saccade than when it is not. We therefore conclude that the adaptation state is linked to actual eye position and that the eye position can serve as a de-adaptation driving error signal. In the third series of experiments we further investigated possible transfer effects of saccadic adaptation to spatial maps of space of covert shifts of attention in visual search or visuospatial memory. The experiments regarding covert attention were unfortunately inconclusive. Possibly direction specificity is not part of the shared representations of overt saccade adaptation and covert search mechanisms. The experiment examining the effect of saccadic adaptation onto visuospatial memory showed an effect on retrieval. Taken together, we have gained further insight into the connections between saccadic adaptation and cognitive functions.

Publications

• (2016). Saccadic adaptation is associated with starting eye position. Frontiers in Human Neuroscience, 10:322
  Gremmler, S. and Lappe, M.
  
• (2016). The influence of image content on oculomotor plasticity. Journal of Vision, 16(8):17-17
  Meermeier, A., Gremmler, S., and Lappe, M.
  
• (2017). New is always better: Novelty modulates oculomotor learning. Journal of Vision, 17(11):13-13
  Meermeier, A., Gremmler, S., and Lappe, M.
  
• (2017). The reward of seeing: Different types of visual reward and their ability to modify oculomotor learning. Journal of Vision, 17(12):11-11
  Meermeier, A., Gremmler, S., Richert, K., Eckermann, T., and Lappe, M.
  
• (2019). Post-saccadic eye position contributes to oculomotor error estimation in saccadic adaptation. Journal of Neurophysiology. 122(5), 1909-1917
  Gremmler, S. and Lappe, M.