Vision and Visual Perception Lecture Flashcards

Comprehensive vocabulary flashcards covering anatomical structures, photopigments, cellular layers, and neural pathways of vision based on the lecture.

Human Visual Spectrum

The small segment of the electromagnetic spectrum that humans can perceive, ranging between $380$ and $800\,\text{nm}$.

Sclera

The white outer membrane of the eye that keeps the internal liquid enclosed.

Cornea

The clear membrane covering the eye that keeps it protected while allowing light to enter.

Iris

The colored muscle of the eye that expands and contracts to regulate incoming light levels, displaying color by reflecting light.

Pupil

The black central opening of the iris that absorbs incoming light without reflecting it.

Lens

The structure behind the iris controlled by muscles that becomes rounder for close objects and flatter for distant objects to focus light onto the fovea.

Retina

The photosensitive layer located at the back of the eye where incoming light forms an upside-down and backwards image.

Fovea

The central focal point on the retina that possesses the most densely packed photoreceptors and provides the greatest visual acuity.

Blind Spot

The specific area on the retina devoid of photoreceptors where optic nerve axons exit the eye.

Rods

Photoreceptors located densely in the periphery of the retina that contain rhodopsin and mediate peripheral vision in low-light environments.

Cones

Photoreceptors concentrated mainly in the fovea that contain iodopsin, function in bright light, and provide high visual acuity and color vision.

Rhodopsin

The photopigment found in rods that is highly active in the dark and breaks down into its component elements when exposed to bright light.

Iodopsin

The photopigment found in cones that functions in bright light and exists in three distinct forms responsive to short, medium, and long wavelengths.

Horizontal Cells

Retinal cells that connect rods and cones to bipolar cells.

Amacrine Cells

Retinal cells that serve as intermediate connecting cells situated between bipolar cells and ganglion cells.

Bipolar Cells

Neurons in the retina that transmit impulses from photoreceptors to ganglion cells and are inhibited by glutamate release in dark conditions.

Receptive Field

The specific area of the retina that gathers incoming visual information for corresponding cells.

Optic Chiasm

The anatomical crossing point where visual nerve fibers cross so that signals from each visual field are directed to the opposite hemisphere of the brain.

Lateral Geniculate Nucleus

The thalamic nucleus situated on the lateral sides of the thalamus that relays visual sensory inputs to the visual cortex in the occipital lobe.

Retinal Disparity

A cue to depth and distance perception that relies on the brain calculating discrepancies between the locations of images projected onto the two separate retinas.