Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Perceptual Constancy

Perceptual Constancy

Perceptual constancy is the ability to recognize that objects remain consistent and unchanged even when their appearance varies due to changes in sensory input. There are four main types of perceptual constancy: size constancy, shape constancy, color constancy, and brightness constancy.
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...

Echo

Echo

The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More than this, and they are perceived as separate sources.
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case,...

Depth Perception and Spatial Vision

Depth Perception and Spatial Vision

Depth perception is the ability to perceive objects three-dimensionally. It relies on two types of cues: binocular and monocular. Binocular cues depend on the combination of images from both eyes and how the eyes work together. Since the eyes are in slightly different positions, each eye captures a slightly different image. This disparity between images, known as binocular disparity, helps the brain interpret depth. When the brain compares these images, it determines the distance to an object.

Perception of Sound Waves

Perception of Sound Waves

The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different frequencies as having different loudness. Moreover, the perception of sound waves depends on the health of an individual's ears, which decays with age. The health of one's ears may also be affected by regular exposure to loud noises.
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same...

Sound Intensity Level

Sound Intensity Level

Humans perceive sound by hearing. The human ear helps sound waves reach the brain, which then interprets the waves and creates the perception of hearing. The loudness of the environment in which a person is located determines whether they can distinguish between different sound sources.
The human ear can perceive an extensive range of sound intensity, necessitating the use of the logarithmic scale to define a physical quantity—the intensity level. It is a ratio of two intensities and...

Equilibrium and Balance

Equilibrium and Balance

The inner ear assumes dual functionalities of auditory perception and equilibrium maintenance. The vestibule is the organ responsible for balance. This organ contains mechanoreceptors, specifically hair cells, endowed with stereocilia, which aid in deciphering information regarding the position and motion of our heads. Two intrinsic components, the utricle and saccule, help perceive head position, while the semicircular canals track head movement. Neurological messages initiated in the...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Linking past and present worlds in the visual control of behavior.

The Behavioral and brain sciences·2026

Same author

A new framework for facial age estimation in humans and AIs.

Scientific reports·2026

Same author

Online corrections to visual targets are not a distinct class of movement.

iScience·2026

Same author

Contribution of auditory distance cues to size constancy in perception and grasping in restricted viewing.

iScience·2025

Same author

Rapid integration of face detection and task set in visually guided reaching.

The European journal of neuroscience·2024

Same author

Changes in primary visual and auditory cortex of blind and sighted adults following 10 weeks of click-based echolocation training.

Cerebral cortex (New York, N.Y. : 1991)·2024

Search research articles

Related Experiment Video

Updated: Apr 28, 2026

Author Spotlight: A Stable Phantom Material for Optical and Acoustic Imaging

Author Spotlight: A Stable Phantom Material for Optical and Acoustic Imaging

Published on: June 16, 2023

A blind human expert echolocator shows size constancy for objects perceived by echoes.

Jennifer L Milne¹, Mimma Anello, Melvyn A Goodale

¹a The Brain and Mind Institute , The University of Western Ontario , London , Ontario , Canada.

|May 31, 2014

Summary

Blind individuals using human echolocation demonstrated size constancy, perceiving object size accurately regardless of distance. This auditory substitute for vision suggests size constancy is not exclusive to sight.

Keywords:

blindness human echolocation multisensory size constancy vision

More Related Videos

Author Spotlight: An Accurate and Quantitative Approach to Study Visual Feature Selectivity of the Optokinetic Reflex in Mice

Author Spotlight: An Accurate and Quantitative Approach to Study Visual Feature Selectivity of the Optokinetic Reflex in Mice

Published on: June 23, 2023

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Published on: September 1, 2016

Related Experiment Videos

Last Updated: Apr 28, 2026

Author Spotlight: A Stable Phantom Material for Optical and Acoustic Imaging

Author Spotlight: A Stable Phantom Material for Optical and Acoustic Imaging

Published on: June 16, 2023

Author Spotlight: An Accurate and Quantitative Approach to Study Visual Feature Selectivity of the Optokinetic Reflex in Mice

Author Spotlight: An Accurate and Quantitative Approach to Study Visual Feature Selectivity of the Optokinetic Reflex in Mice

Published on: June 23, 2023

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects

Published on: September 1, 2016

Area of Science:

Neuroscience
Auditory Perception
Sensory Substitution

Background:

Human echolocation, using mouth clicks to interpret echoes, serves as a sensory substitute for vision in some blind individuals.
Echolocation enables perception of distal, silent objects, functioning as a rudimentary visual system.
Size constancy, the perception of an object's actual size despite changes in its retinal image size due to distance, is a well-established visual phenomenon.

Observation:

The study investigated whether human echolocation exhibits size constancy, similar to vision.
A blind expert echolocator (EE) was tasked with echolocating objects of varying physical sizes at different distances.
Control participants included blind and blindfolded sighted individuals, who were encouraged to use auditory signals.

Findings:

The expert echolocator demonstrated accurate perception of true object size, independent of distance, indicating size constancy via echolocation.
Control participants, even when using auditory cues, did not exhibit size constancy.
This suggests that the ability to perceive stable object size is achievable through auditory means.

Implications:

Size constancy is not limited to visual processing and can be achieved through auditory sensory substitution.
Human echolocation provides a unique model for understanding perceptualconstancy beyond the visual domain.
These findings open new avenues for research into non-visual spatial perception and sensory rehabilitation.