NEU 101: Vision II

These flashcards cover key vocabulary and concepts related to vision and the visual system as discussed in Lecture NEU 101.

Trichromacy

The theory that three types of cones in the retina give rise to color perception.

Lateral Geniculate Nucleus (LGN)

A major processing center for visual information in the thalamus.

Optic Nerve

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

Optic Chiasm

The point at which the optic nerves cross, allowing visual information from both eyes to be processed.

Horizontal Cells

Neurons in the retina that help integrate and regulate the spontaneous activity of bipolar cells.

Ganglion Cells

Retinal neurons that form the optic nerve, transmitting visual information from the retina to the brain.

Neural Convergence

The process where multiple neurons connect to a single neuron, allowing for integration of information.

Receptive Field

The specific area of the retina that influences the activity of a particular neuron in the visual system.

Graded Potentials

Changes in membrane potential that are not all-or-nothing, varying in degree.

Action Potentials

Rapid, all-or-nothing signals that can be propagated along the axon of a neuron.

Vertical Circuits

Neural pathways that carry information from sensory receptors toward the central nervous system.

Horizontal Circuits

Neural pathways that connect neighboring cells and can modify the information transmitted by vertical circuits.

Acuity

The sharpness or clarity of vision, often improved by lower convergence of photoreceptor cells.

Sensory Receptors

Cells that detect sensory stimuli and convert them into neural signals.

Rod Cells

Photoreceptors in the retina sensitive to low levels of light, responsible for night vision.

Cone Cells

Photoreceptors in the retina that are responsible for color vision and function best in bright light.

Center-Surround Receptive Fields

Receptive fields organized with a central zone sensitive to light surrounded by a zone that inhibits responses.

Bipolar Cells

Retinal neurons that receive input from photoreceptors and transmit signals to ganglion cells.

Convergence & Sensitivity

The relationship describing how multiple photoreceptor inputs can enhance the sensitivity of ganglion cells.

Parvocellular Cells

Type of ganglion cells involved in processing fine detail and color information.

Magnocellular Cells

Type of ganglion cells primarily responsible for motion detection and low-light vision.

Excitatory Neurons

Neurons that increase the likelihood of the firing of other neurons.

Inhibitory Neurons

Neurons that decrease the likelihood of the firing of other neurons.

Fovea

The central region of the retina where visual acuity is highest due to a high concentration of cones.

Macula

The area of the retina responsible for central vision.

Retinal Blood Vessels

The blood supply that nourishes the retina.

Neural Circuitry

The interconnected pathways of neurons that process sensory information.

Sensation

The process of detecting physical energy from the environment and transforming it into neural signals.

Perception

The process of organizing and interpreting sensory information.

Visual Pathway

The route that visual information takes from the retina to the visual cortex.

Visual Field

The entire area that can be seen when the eyes are in a fixed position.

Nasal Hemiretina

The part of the retina closest to the nose.

Temporal Hemiretina

The part of the retina closest to the temple.

Light Rays

Electromagnetic radiation that is visible to the human eye, responsible for vision.

Bipolar Cell Layers

Layers in the retina structured with bipolar cells that facilitate signal transmission.

Concentration of Cones

Refers to the density of cone cells in the central retina, affecting color perception.

Threshold of Excitation

The level at which ganglion cells begin to fire action potentials.

Retina

The light-sensitive layer of tissue at the back of the eye.

Center-Surround Antagonism

A concept illustrating how the center and surrounding areas of a receptive field interact.