PNS, Pain, and Aging Flashcards

Flashcards covering the peripheral nervous system, physiology of pain, and effects of aging on the nervous system.

What is the main component of the Peripheral Nervous System?

Nerves leading to and from the CNS.

What are the two functional divisions of the PNS?

Sensory and motor divisions.

What is the role of the sensory (afferent) division of the PNS?

Carries signals from receptors to the CNS.

Why does the sensory division of the PNS carry signals from receptors to the CNS?

To provide information about environmental changes.

What is the role of the motor (efferent) division of the PNS?

Carries signals from the CNS to effectors.

Give an example of effectors that respond to signals from the motor division.

Muscles and glands.

What are the two subdivisions of the motor division?

Somatic motor division and autonomic nervous system (ANS).

What is the function of the somatic motor division?

Carries signals to skeletal muscles.

What does the autonomic nervous system (ANS) carry signals to?

Cardiac muscle, smooth muscle, and glands.

What are the two divisions of the autonomic nervous system (ANS)?

Sympathetic and parasympathetic divisions.

What is the primary function of the sympathetic division?

Prepares the body for action.

What is the primary function of the parasympathetic division?

Calms the body and slows the heartbeat, stimulates digestion.

What kind of stimuli does sensory division transmit?

Stimuli from the periphery to the CNS.

What is the function of the somatic nervous system motor division?

Stimuli from CNS to skeletal muscles

What is the main function of the parasympathetic division?

"Rest and digest".

What is the main function of the sympathetic division?

"Fight and flight".

What structures are part of the enteric nervous system?

Myenteric and submucosal plexuses.

What are the effector organs of the somatic motor system?

Skeletal muscles.

Are there ganglia in the somatic motor system?

No ganglia.

What are the effector organs of the autonomic motor system?

Cardiac muscle, smooth muscle, and glands.

Where are the cell bodies of postganglionic autonomic fibers located?

Located in paravertebral, prevertebral, and terminal ganglia.

Where are the CNS locations of preganglionic neuron cell bodies in the sympathetic system?

Thoracic and lumbar spinal cord.

Where are the CNS locations of preganglionic neuron cell bodies in the parasympathetic system?

Brainstem and sacral spinal cord.

What is the sympathetic response on the heart?

Increase rate.

What is the parasympathetic response on the heart?

Decrease rate (to resting normal).

What is the sympathetic response on the bronchioles?

Dilate.

What is the parasympathetic response on the bronchioles?

Constrict (to normal).

How is pain defined?

Unpleasant sensory and emotional experience associated with tissue damage.

What are the benefits of Pain Sensation?

Gives warning signal about a problem, prevents further damage, forces rest, urges treatment.

What type of stimuli stimulates the pain receptors?

Chemical, mechanical, and thermal stimuli.

What is the pathway for fast pain?

Neospinothalamic tract.

What are the 1st order neurons of the Fast Pain pathway?

A delta fibers.

What is the chemical transmitter released at the central end of A delta fibers that carry fast pain?

Glutamate.

What is the pathway of slow pain?

Paleospinothalamic tract.

What are the 1st order neurons of the Slow Pain pathway?

C afferent fibers.

What is the chemical transmitter released at the central end of c fibers that carry slow pain?

Substance P.

What stimuli causes acute (fast) pain?

Mechanical and thermal stimuli.

What stimuli causes chronic (slow) pain?

Chemical stimuli.

What afferent fibers are found in acute (fast) pain?

A-delta.

What afferent fibers are found in chronic (slow) pain?

C fibers.