Does the Muller-Lyer illusion induced by a goalkeeper configuration influence soccer penalty kicks?

TL;DR

This study investigates whether the Muller-Lyer illusion, induced by goalkeeper arm configurations, affects soccer penalty kicks, finding perceptual biases do not translate into altered kicking behavior, with other contextual cues playing a larger role.

Contribution

It demonstrates that while goalkeeper configurations can induce perceptual illusions, these do not influence penalty kick actions, highlighting the role of contextual cues over perceptual biases.

Findings

Perceived size aligned with the Muller-Lyer illusion.

Penalty kicks were influenced more by goalkeeper proximity and available space.

No correlation between perceptual bias and kicking behavior.

Abstract

In soccer penalty kicks, goalkeepers that orient their arms upward compared to downward can be misperceived as being taller - effectively recreating the Muller-Lyer illusion. The present study elaborates on previous research surrounding a potential illusion-induced bias in penalty kicks. Participants were exposed to goalkeeper configurations within a virtual goal including arms-parallel, arms-down, arms-out and arms-up. They separately judged the perceived size of the goalkeeper, and executed penalty kicks. The perceived size was near fully consistent with the intended illusion. Meanwhile, the penalty kicks indicated wider a horizontal position following arms-out, and lower vertical position following arms-up. Likewise, there was no relation between the biases expressed in perception and action. While goalkeepers can elicit a perceptual illusion, this does not extend to influencing the penalty kick itself. Instead, other contextual cues appeared more relevant including the proximity between the goalkeeper and goalposts, and with it, the available space in the goal.