Peripheral and Central Anatomy and Physiology

Vestibular System

A sensory system that helps maintain balance and posture.

Triad

The three systems that work together for balance:vestibular, vision, and proprioception.

Amniotes

Organisms that are not water-bodied and rely on the vestibular system for balance.

Rigid Body Motion

The six possible movements of a rigid body:up and down, side to side, rotation (yaw), and front to back (pitch).

Otolith Organs

Sensory structures that record linear accelerations; includes utricle and saccule.

Utricle

An otolith organ that detects front and back/horizontal movement.

Saccule

An otolith organ that detects up and down/vertical movement.

Semicircular Canals

Structures that detect rotational movements; includes horizontal, superior, and posterior canals.

Ampulla

Sensory structures that act as a barrier between semicircular canals and the utricle.

Vestibular Ocular Pathway

A pathway that helps maintain stable vision during head movements.

Vestibularospinal Pathway

A pathway that helps maintain stable posture.

Crista

The sensory structure within the semicircular canals.

Cupula

A gelatinous mass that hair bundles of the crista attach to.

Otoconia

Calcium carbonate crystals embedded in the otolithic membrane that affect balance.

Kinocilium

The tallest hair cell in the vestibular system.

Ewald’s Law

A principle stating that stimulation of the semicircular canal generates eye movements in the direction of the canal's excitation.

What is the ipsilateral vestibular pathway?

VN → INC →

What do the semicircular canals code?

movement in different planes