Damage to the ampullary cupula of the lateral semicircular duct would interfere with the perception of
(a) The direction of gravitational pull
(b) Linear acceleration
(c) Horizontal rotation of the head
(d) Vertical rotation of the head
(e) Angular rotation of the head

Verified step by step guidance

1. Understand the anatomy and function of the ampullary cupula: It is a gelatinous structure located within the ampulla of each semicircular canal in the inner ear, specifically involved in detecting rotational movements of the head.
2. Recall that the lateral semicircular duct (or canal) is oriented roughly horizontally and is primarily responsible for detecting horizontal (side-to-side) rotations of the head.
3. Recognize that the ampullary cupula bends in response to the movement of endolymph fluid within the semicircular canals during angular (rotational) acceleration, which stimulates hair cells to send signals about head rotation.
4. Differentiate between types of motion: gravitational pull and linear acceleration are detected by the otolith organs (utricle and saccule), not the semicircular canals; vertical rotation involves other canals (anterior and posterior).
5. Conclude that damage to the ampullary cupula of the lateral semicircular duct would specifically interfere with the perception of horizontal angular rotation of the head.

Key Concepts

Ampullary Cupula and Semicircular Canals

The ampullary cupula is a gelatinous structure located within the ampulla of each semicircular canal in the inner ear. It bends in response to fluid movement caused by head rotation, stimulating hair cells that send signals about angular motion to the brain.

Function of the Lateral Semicircular Duct

The lateral semicircular duct specifically detects horizontal or yaw rotation of the head. When the head turns side to side, the fluid movement in this duct deflects the cupula, allowing the brain to perceive horizontal angular acceleration.

Types of Motion Perceived by the Vestibular System

The vestibular system senses different motions: gravitational pull (static tilt), linear acceleration (straight-line movement), and angular rotation (head turning). Semicircular canals primarily detect angular rotation, while otolith organs detect gravity and linear acceleration.