Related Experiment Video
Updated: May 29, 2026
04:32
Sound Source Localization Testing in Single-sided Deafness Following Bone Conduction Intervention
Published on: December 20, 2024
The basis for using bone-conducted vibration or air-conducted sound to test otolithic function
I S Curthoys1, V Vulovic, A M Burgess
1Vestibular Research Laboratory, School of Psychology, University of Sydney, Sydney, New South Wales, Australia. ianc@psych.usyd.edu.au
Annals of the New York Academy of Sciences
|September 29, 2011
Summary
Low-intensity sound and vibration activate otolith vestibular neurons. Oculomotor and neck muscle responses can selectively probe utricular and saccular function, respectively.
Area of Science:
- Neuroscience
- Vestibular System Physiology
Background:
- The vestibular system, crucial for balance and spatial orientation, comprises otolith organs (utricle and saccule) and semicircular canals.
- Understanding the differential activation and projection of vestibular neurons is key to diagnosing balance disorders.
Purpose of the Study:
- To investigate the effects of low-intensity bone-conducted vibration (BCV) and air-conducted sound (ACS) on primary vestibular neurons.
- To determine if BCV and ACS can selectively probe the function of the utricle and saccule.
Main Methods:
- Extracellular single neuron recordings in guinea pig Scarpa's ganglion.
- Electrophysiological recordings of otolith-evoked eye movements and myogenic potentials in humans and guinea pigs.
Main Results:
- 500 Hz BCV and ACS activated a high proportion of otolith irregular neurons from both the utricle and saccule, with minimal activation of semicircular canal neurons.
- In humans and guinea pigs, 500 Hz BCV elicited otolith-evoked eye movements, predominantly reflecting utricular function.
- In humans, 500 Hz BCV also elicited myogenic potentials in sternocleidomastoid muscles, reflecting saccular function.
Conclusions:
- Low-intensity sound and vibration effectively activate otolith vestibular pathways.
- Differential neural projections allow for selective assessment of utricular (via oculomotor responses) and saccular (via neck muscle responses) function using BCV and ACS.
Related Concept Videos
01:13The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
01:15Equilibrium 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...
01:16Anatomy of the Ear
Auditory sensation, commonly called hearing, involves the transformation of sonic waves into neural impulses facilitated by the structures of the auditory organ. The prominent, flesh-like structure on the side of the head, called the auricle, directs sound waves towards the auditory canal. The auricle is often mislabeled as the pinna, a term more aligned with mobile structures like a feline's external ear. The auditory canal penetrates the cranium via the external auditory meatus of the...
01:11The Auditory Ossicles
The auditory ossicles of the middle ear transmit sounds from the air as vibrations to the fluid-filled cochlea. The auditory ossicles consist of two malleus (hammer) bones, two incus (anvil) bones, and two stapes (stirrups), one on each side. These bones develop during the fetal stage and are the ones to ossify first. They are fully mature at birth and do not grow afterward.
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...
01:15Auditory Pathway
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
01:31Hearing
When we hear a sound, our nervous system is detecting sound waves—pressure waves of mechanical energy traveling through a medium. The frequency of the wave is perceived as pitch, while the amplitude is perceived as loudness.