Lab 9: Somatic Sensory Receptors

Flashcards covering key vocabulary and concepts from Lab 9 on somatic sensory receptors.

Afferent division

Signals that travel towards the CNS (arrive).

Efferent division

Signals that travel from the CNS (exit).

Mixed Nerves

All spinal nerves contain both afferent and efferent fibers.

Cranial Nerves

The twelve pairs of nerves that arise directly from the brain.

Dermatome

An area of skin that sends information to the brain via a single spinal nerve.

Receptive Field

The area monitored by a single receptor.

Nociceptors

Sensory receptors that detect pain.

Thermoreceptors

Receptors that detect temperature changes (heat and cold).

Mechanoreceptors

Receptors that respond to touch, pressure, and vibration.

Somatic sensory receptors

Receptors that monitor skeletal muscles, joints, and skin surface.

First Order Neurons

Sensory neurons that carry signals to the spinal cord.

Second Order Neurons

Interneurons that relay signals to the thalamus.

Third Order Neurons

Neurons that transmit signals from the thalamus to the somatosensory cortex.

Phasic Receptors

Receptors that are normally inactive and respond to changes in conditions.

Tonic Receptors

Receptors that are always active and reflect background levels of stimulation.

Two Point Discrimination Test

A test to determine the ability to perceive two close points as separate.

Fine Touch

Sensitivity to small changes in pressure or texture.

Somatosensory Cortex

Area of the brain that processes sensory input from the body.

Cortical Area

The brain region that corresponds to the density of sensory receptors.

Exteroceptors

Sensory receptors that provide information about the external environment.

Interoceptors

Sensory receptors that monitor internal organ activity and states.

Proprioceptors

Sensory receptors that monitor the position and movement of skeletal muscles and joints.

Chemoreceptors

Sensory receptors that detect chemical changes, such as in smell, taste, or blood $pH$.

Photoreceptors

Sensory receptors that detect light, primarily found in the retina of the eye.