Egocentric reference and asymmetric perception of space

Area of Science:

• Neuroscience
• Cognitive Psychology
• Human Perception

Background:

• The pseudoneglect phenomenon describes a leftward bias in spatial attention for healthy individuals.
• Existing research often focuses on visual neglect, with less attention to tactilo-kinesthetic tasks.
• The role of the egocentric reference frame in spatial perception requires further investigation.

Purpose of the Study:

• To investigate spatial perception during tactilo-kinesthetic bisection tasks.
• To examine the influence of gaze direction and hand use on the subjective sense of the median position.
• To explore the relationship between spatial perception, egocentric reference frame, and activation theory.

Main Methods:

• Normal right-handed participants performed tactilo-kinesthetic line bisection tasks.
• Tasks were conducted with the hand in a median position.
• Three gaze directions were tested: 30 degrees left, 30 degrees right, and straight ahead (0 degrees).

Main Results:

• A deviation of the subjective middle was observed, consistently opposite to the direction of gaze and hand use.
• This deviation occurred regardless of which hand was used for the task.
• The findings did not support the typical pseudoneglect phenomenon in this specific task paradigm.

Conclusions:

• Spatial perception is influenced by the interplay between gaze direction and hand use.
• The observed deviations suggest a dynamic shift in the egocentric reference frame.
• Pseudoneglect may be a specific instance of a more general spatial asymmetry dependent on egocentric reference.