English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Previous research investigating eye movements when grasping objects with precision grip has shown that we tend to fixate close to the contact position of the index finger on the object. It has been hypothesized that this behavior is related to the fact that the index finger usually describes a more variable trajectory than the thumb and therefore requires a higher amount of visual monitoring. We wished to directly test this prediction by creating a grasping task in which either the index finger or the thumb described a more variable trajectory. Experiment 1 showed that the trajectory variability of the digits can be manipulated by altering the direction from which the hand approaches the object. If the start position is located in front of the object (hand-before), the index finger produces a more variable trajectory. In contrast, when the hand approaches the object from a starting position located behind it (hand-behind), the thumb produces a more variable movement path. In Experiment 2, we tested whether the fixation pattern during grasping is altered in conditions in which the trajectory variability of the two digits is reversed. Results suggest that regardless of the trajectory variability, the gaze was always directed toward the contact position of the index finger. Notably, we observed that regardless of our starting position manipulation, the index finger was the first digit to make contact with the object. Hence, we argue that time to contact (and not movement variability) is the crucial parameter which determines where we look during grasping.

Why do the eyes prefer the index finger? Simultaneous recording of eye and hand movements during precision grasping