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Related Concept Videos

Apparent Weight01:09

Apparent Weight

True weight is the measure of the gravitational force acting on an object. However, if the object accelerates, its measured weight is different from its true weight. Similar observations can be made when the object is submerged in water. An object's weight in water is its apparent weight, which is equal to the difference between its true weight and the buoyant forces.
Consider a person standing on a bathroom scale inside an elevator. If the scale is accurate at rest, its reading equals the...
Perceptual Constancy01:12

Perceptual Constancy

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Variation in Acceleration due to Gravity near the Earth's Surface

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Apparent Weight and the Earth's Rotation01:28

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The Anchoring-and-Adjustment Heuristic01:25

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In order to make good decisions, we use our knowledge and our reasoning. Often, this knowledge and reasoning is sound and solid. However, sometimes, we are swayed by biases or by others manipulating a situation. For example, let’s say you and three friends wanted to rent a house and had a combined target budget of $1,600. The realtor shows you only very run-down houses for $1,600 and then shows you a very nice house for $2,000. Might you ask each person to pay more in rent to get the $2,000...
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A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss
07:12

A Gaze-Contingent Display Framework for Perceptual Learning Research with Simulated Central Vision Loss

Published on: April 11, 2025

Perceptual learning: inverting the size-weight illusion.

Marc O Ernst1

  • 1Max Planck Institute for Biological Cybernetics, Spemannstr. 41, 72076 Tübingen, Germany. marc.ernst@tuebingen.mpg.de

Current Biology : CB
|January 14, 2009
PubMed
Summary
This summary is machine-generated.

The size-weight illusion, where smaller objects feel heavier, can be reversed. Extensive training with artificially altered size-weight relationships inverts this common perception.

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Area of Science:

  • Perception science
  • Human sensory integration
  • Motor control

Background:

  • The size-weight illusion describes the phenomenon where objects of identical weight are perceived as heavier when smaller.
  • This illusion is a well-established aspect of human sensory perception and motor control.
  • Previous research has primarily focused on the conditions that elicit this illusion.

Discussion:

  • This study investigated the plasticity of the size-weight illusion through targeted training protocols.
  • Participants underwent training where the typical relationship between object size and perceived weight was inverted.
  • The results demonstrate that extensive training can significantly alter and even invert the size-weight illusion.

Key Insights:

  • The human perception of weight is not solely based on physical properties but is heavily influenced by learned associations and context.
  • The size-weight illusion is malleable and can be overcome or reversed with specific, prolonged sensory-motor training.
  • This finding has implications for understanding perceptual learning and sensorimotor adaptation.

Outlook:

  • Further research could explore the neural mechanisms underlying the reversal of the size-weight illusion.
  • Investigating the long-term stability of this inverted illusion is crucial.
  • Applications may include rehabilitation or training programs requiring recalibration of sensory perception.