The Peripheral and Autonomic Nervous System Anatomy and Physiology Blake Austin College Licensed Vocational Nursing Program Semester 1 The Peripheral and Autonomic Nervous System

Objectives Describe a mixed nerve Describe the functions of the cranial and spinal nerves Relate the functions of the sympathetic and parasympathetic nervous system Explain the simple reflex arc pattern Describe common disorders of the peripheral nervous system Define the key words that relate to this chapter

Peripheral Nervous System Nerves that connect the brain and spinal cord with sensory receptors, muscles, and glands Two subcategories Afferent peripheral system Consists of afferent or sensory neurons that convey information from receptors in the periphery of the body to the brain and spinal cord Efferent peripheral system Consists of efferent or motor neurons that convey information from the brain and spinal cord to the muscles and glands

Efferent Peripheral System Somatic nervous system voluntary movement of skeletal muscles Autonomic nervous system (think “autonomic = automatic”) Sympathetic Stimulates or speeds up activity and thus requires an energy expenditure and uses norepinephrine as a neurotransmitter Fight-or-Flight System Parasympathetic Most active under ordinary, relaxed conditions Rest-and-Repose System (energy-conserving system)

Efferent

Autonomic

Nerves Bundles of nerve fibers enclosed by connective tissue Sensory or afferent nerves Motor or efferent nerves Mixed nerves

Cranial and Spinal Nerves Part of the peripheral nervous system 12 pairs of cranial nerves 31 pairs of spinal nerves

Cranial Nerves I (Olfactory) II (Optic) III (Oculomotor) IV (Trochlear) V (Trigeminal) VI (Abducens) VII (Facial) VIII (Vestibulocochlear) IX (Glossopharyngeal) X (Vagus) XI (Spinal accessory) XII (Hypoglossal)

Cranial Nerves

Spinal Nerve Plexus Cervical plexus Brachial plexus Lumbar plexus Sacral plexus

Autonomic Nervous System Nerves, ganglia, and plexuses which carry impulses to all smooth muscle, secretory glands, and heart muscle Two divisions Sympathetic system Parasympathetic system Both are strongly influenced by emotion http://www.youtube.com/watch?v=m2GywoS77qc

Reflex Act Simplest type of nervous response Unconscious and involuntary Reflexive acts Stimulus Change in the environment Receptors Sensory nerve that receives a stimulus and transmits it to the CNS Response Reaction to a stimulus Reflex actions, or autonomic reflexes, involving the skeletal muscles are controlled by the spinal cord

Reflex Arc http://www.youtube.com/watch?v=wLrhYzdbbpE

Biofeedback Measurement of physiological responses Yields information about the relationships between the mind and the body Can learn to manipulate these responses through mental activity http://www.youtube.com/watch?v=elbarHFHVRM

Disorders Neuritis Peripheral neuropathy Sciatica Neuralgia Trigeminal neuralgia Bell’s palsy Shingles or herpes zoster Carpal tunnel syndrome