chat review

Somatosensory Transduction

The process of converting mechanical stimuli into electrical signals through ion channels in sensory receptors.

Ion Channels

Proteins in the cell membrane that open in response to mechanical pressure, allowing ions like sodium to create an electrical signal.

Receptive Fields

Areas of sensory neurons where the stimulus can elicit a response, characterized by center-surround organization.

Center-Surround Fields

Receptive fields where touch in the center causes excitation and touch in the surround causes inhibition.

Aphasic Response

A type of sensory response characterized by a brief burst of firing followed by silence.

Consistent Response

A sustained firing of neurons as long as a stimulus is present.

Homunculus

A map in the primary somatosensory cortex representing body parts in proportion to their sensory importance.

Free Nerve Endings

Sensory receptors that detect pain, temperature, and chemical irritation.

A-Delta Fibers

Myelinated nerve fibers responsible for transmitting sharp, immediate pain.

C Fibers

Unmyelinated nerve fibers responsible for transmitting dull, lingering pain.

Dorsal Column Pathway

The pathway that carries touch and proprioception signals crossing at the medulla.

Lateral Pathway

The pain pathway that carries pain and temperature signals, crossing immediately at the spinal cord.

Gate Control Theory

The theory that non-painful stimuli can reduce pain by closing the gate to pain signals.

TENS Stimulation

A method of pain relief involving electrical stimulation that activates non-pain touch fibers.

Primary Somatosensory Cortex (S1)

Located in the postcentral gyrus of the parietal lobe, processing contralateral sensory input.

Photoreceptors

Cells in the retina that detect light; includes rods for dim light and cones for color.

Optic Chiasm

The point where some visual information crosses to the opposite side of the brain.

LGN (Lateral Geniculate Nucleus)

A thalamic relay center for visual information before it reaches the primary visual cortex.

Trichromatic Theory

A theory stating that three types of cones detect different wavelengths of light.

Dorsal Stream

The visual pathway that tracks object location, often referred to as the 'Where' pathway.

Ventral Stream

The visual pathway that identifies objects, often referred to as the 'What' pathway.