Unit 8: Senses & Proprioception

Exteroceptors

Senses such as vision, hearing, smell, taste, touch, and equilibrium. They record information about the body’s external environment.

Visceroceptors

Second set of receptors that monitors conditions of the body’s internal environment and are important for the maintenance of homeostasis (HR, BP, body temp, blood pH, ion concentration).

Proprioceptors

Third set of receptors that determine your body’s relative position with respect to gravity (up vs down), and whether your body is stationary or moving.

1. Pressure

2. Temp

3. Pain

Skin detects three primary modalities.

Meissner’s (light touch), Pacinian Corpuscles (deep pressure)

Pressure or touch receptors.

Hair root plexus

Detects pressure or touch, nerve endings wrapped around the bulbs of hairs

Nociceptors

Free nerve endings in the upper reaches of skin help detect temp as well as pain, which is accomplished through special receptor sets called__________.

Proprioception

Nerve endings in muscles and joints help give the body a sense of____________, the body’s sense of its position in space.

Muscle spindles and golgi

Two receptors used for proprioception. These receptors are also linked into many of the muscular reflexes of the body.

Gauging amount of contraction/relaxation in muscles and tension in tendons

How is proprioception sensed?

Semicircular ducts and utricle/saccule complex

Specific ear organs involved in proprioception.

Chemoreceptors

Sense chemicals in solution, receptors used for smell and taste

Cranial Nerve I (Olfactory)

Smell is conducted by the ___________nerve, where odors are registered by nerve receptors that detect chemicals dissolved in the thin layer of fluid that coats our nasal mucosa.

Taste buds

Chemoreceptors for taste are arranged in units called _______ that are preferentially sensitive to sweet, sour, salty, bitter, and glutamate ligands.

Ligand

A flavor stimulating chemical

Cranial Nerve VII (Facial), Cranial Nerve IX (Glossopharyngeal), Cranial Nerve X (Vagus), Cranial Nerve V (Trigeminal)

Control of taste is managed by several different Cranial nerves, anterior 2/3 of tongue by __________, posterior 1/3 by ________, and there are taste receptors in the throat managed by__________. Additionally, food textures, perceptions of solid vs liquid, food temperatures, and potential perceptions of pain are perceived by________

F; there is a decrease

T/F: there is surprisingly no change in somatic sensations with age

Peripheral neuropathy

One of the hallmarks of patients who have lived with diabetes, long-term is_________or a degeneration of the peripheral sensors and sensations.

Oxidative effects of long-term, high levels of glucose in the bloodstream (Free Radical Theory of Aging).

What causes peripheral neuropathy? What theory of aging does it relate to?

Ulcer, infections, gangrene and amputation.

Short-term and long-term consequences of peripheral neuropathy.

True

T/F: much of the loss in proprioception of muscles, joints and tendons is due to the progressive decline of the nervous system and muscle mass that occurs with aging