Related Experiment Video
Updated: Nov 11, 2025
10:51
Frame-by-Frame Video Analysis of Idiosyncratic Reach-to-Grasp Movements in Humans
Published on: January 15, 2018
8.6K
Perceiving action boundaries for overhead reaching in a height-related situation
Lisa P Y Lin1, Sally A Linkenauger2
1Department of Psychology, Fylde College, Lancaster University, Bailrigg, Lancaster, LA1 4YF, UK. l.lin1@lancaster.ac.uk.
Attention, Perception & Psychophysics
|March 30, 2021
Summary
Individuals learn action boundaries from variable experiences. This study found that while people use similar strategies for estimating reachability, they adopt more conservative action boundaries in height-related contexts.
Area of Science:
- Motor control and perception
- Human-environment interaction
- Action boundary learning
Background:
- Action boundaries define the limits of human motor performance.
- Learning action boundaries involves processing variable perceptual-motor feedback across contexts.
- Previous research indicated a liberal action boundary for horizontal reaching, irrespective of variability type.
Purpose of the Study:
- To investigate if action boundary determination strategies vary across different reach types and environmental contexts.
- To examine how perceptual systems adapt to variability in reach experience.
- To understand the influence of environmental context, particularly height, on action boundary estimation.
Main Methods:
- Participants experienced reaching with virtual arms of varying lengths (long, short, variable).
- Reachability estimates were made in two contexts: standing on a rooftop (height-related) and on the ground (non-height-related).
- Analysis focused on how participants adjusted their action boundaries based on prior reaching experience and context.
Main Results:
- Participants employed similar strategies for determining action boundaries in both height-related and non-height-related contexts.
- Reachability estimates were significantly more conservative in the height-related context compared to the ground context.
- Participants demonstrated sensitivity to probabilistic information from varied reaching experiences, using a weighted average to set boundaries under uncertainty.
Conclusions:
- Action boundary determination strategies are adaptable based on environmental context, particularly concerning safety-critical situations like height.
- The perceptual system integrates probabilistic information from motor experience to establish action boundaries under uncertainty.
- Environmental context significantly influences the conservatism of action boundaries, even when underlying strategies remain similar.
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