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Updated: May 29, 2026
09:35
Measurement of the Hand Transmitted Vibration of the Human Hand Arm System During Operation of a Hand Tractor
Published on: June 16, 2021
A 2.5-D representation of the human hand
Matthew R Longo1, Patrick Haggard
1Department of Psychological Sciences, Birkbeck, University of London, London, UK. m.longo@bbk.ac.uk
Journal of Experimental Psychology. Human Perception and Performance
|September 8, 2011
Summary
Brain maps represent the body in 2-D, but we perceive it as a 3-D object. This study reveals distortions in hand representation, suggesting a hybrid 2-D/3-D model for body perception.
Area of Science:
- Neuroscience
- Somatosensory System
- Body Representation
Background:
- The brain's somatosensory maps fragment the body into 2-D skin regions, contrasting with our coherent 3-D volumetric self-perception.
- Understanding the integration of 2-D sensory input with 3-D body schema is crucial for spatial awareness.
Purpose of the Study:
- To investigate if distortions in body representation are consistent across the entire 3-D hand or specific to each 2-D skin surface.
- To determine the relationship between dorsal and palmar hand representations.
Main Methods:
- Participants localized points on the dorsal and palmar hand surfaces in external space.
- Implicit maps of each skin surface were generated by analyzing judgment configurations.
- Distortion patterns were compared between the two surfaces and across participants.
Main Results:
- Qualitatively similar distortions were found on both dorsal and palmar hand surfaces.
- Correlations in distortions across participants suggest a unified underlying hand representation.
- Distortion magnitude was significantly smaller on the palmar surface, indicating incomplete integration.
Conclusions:
- The implicit representation of the human hand is likely a hybrid model.
- This model integrates 2-D surface-specific information with a developing 3-D volumetric representation.
- The binding between different hand surfaces is incomplete, influencing body perception.
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