Comprehensive Review of Visual System: Retina, Photoreceptors, and Visual Processing

What is myopia?

Myopia, also known as nearsightedness, is a condition where distant objects appear blurry while close objects can be seen clearly.

What is hyperopia?

Hyperopia, or farsightedness, is a condition where close objects appear blurry while distant objects can be seen more clearly.

What are photoreceptors?

Photoreceptors are specialized cells in the retina that convert light into electrical signals; they include rods and cones.

What is the function of rods in the retina?

Rods are photoreceptors that are sensitive to low light levels and are responsible for night vision.

What is the fovea?

The fovea is a small depression in the retina where visual acuity is highest, containing a high density of cones.

What is the role of ganglion cells in the retina?

Ganglion cells receive input from photoreceptors and transmit visual information to the brain via the optic nerve.

What is lateral inhibition?

Lateral inhibition is a process where excited neurons inhibit the activity of neighboring neurons, enhancing contrast in visual perception.

What is the Purkinje shift?

The Purkinje shift refers to the phenomenon where the peak sensitivity of the human eye shifts toward shorter wavelengths in low light conditions.

What is the significance of the receptive field?

The receptive field is the specific area of the visual field where a stimulus will affect the firing of a neuron, influencing how visual information is processed.

What is dark adaptation?

Dark adaptation is the process by which the eyes become more sensitive to low light levels after being in bright light.

What is the function of cones in the retina?

Cones are photoreceptors responsible for color vision and function best in bright light conditions.

What is the role of the optic nerve?

The optic nerve carries visual information from the retina to the brain for processing.