Chapter 1-9 Key Terms Review

Vocabulary flashcards covering key terms from the notes on vision, spatial orientation, and vestibular physiology related to flight.

Pupil

The opening in the iris that regulates light entry into the eye.

Iris

The colored part of the eye that controls pupil size in response to light.

Cornea

The transparent front surface of the eye that light passes through and begins focusing.

Lens

The eye structure that further focuses light onto the retina; changes shape for focusing (accommodation).

Retina

The light-sensitive layer at the back of the eye connected to the optic nerve; contains photoreceptors.

Optic nerve

The nerve that transmits visual information from the retina to the brain.

Cones

Photoreceptors responsible for color vision and sharp central vision; function best in bright light and are concentrated in the fovea.

Rods

Photoreceptors responsible for peripheral and low-light vision; function in darkness.

Fovea

The small central pit of the retina with high cone density where vision is sharpest when looking directly at an object.

Off-center scanning

Scanning about 5–10 degrees away from the object to use peripheral vision rather than staring directly.

Autokinesis

Illusion that a stationary light appears to move when stared at in darkness.

Spatial disorientation

Lack of orientation with respect to the aircraft's position, attitude, or movement in space, caused by conflicting cues.

Vestibular system

Inner-ear system that helps sense head motion and orientation; includes semicircular canals and otolith organs.

Semicircular canals

Vestibular structures that sense rotational movement (pitch and roll) through hair-cell deflection.

Otoliths (statoliths)

Calcium carbonate crystals in the vestibular system that sense gravity and linear acceleration by deflecting hair cells.