Peripheral Nervous System Includes 1 Cranial nerves 2
- Slides: 9
Peripheral Nervous System • Includes: 1. Cranial nerves 2. Spinal nerves • Can also be divided into: 1. Somatic nervous system – controls conscious activities 2. Autonomic nervous system – controls unconscious activities
Cranial Nerves • Where would these originate? • 12 pairs – 1 st pair originates in the cerebrum – The rest originate from the brain stem
Cranial Nerves, continued…. . 1. 2. 3. 4. Olfactory nerves (I) Optic nerves (II) Oculomotor nerves (III) Trochlear nerves (IV) – smallest; takes impulses to a muscle that moves the eye 5. Trigeminal nerves (V) – largest cranial nerves 1. Ophthalmic division – sensory info from eyes 2. Maxillary division – sensory info from upper mouth 3. Mandibular division – sensory info from scalp behind ears and lower mouth
Cranial Nerves, continued…. . 6. Abducens nerves (VI) – small; motor impulses to move eye 7. Facial nerves (VII) – 1. Sensory associated with taste receptors 2. Motor impulses to facial muscles and tear glands and salivary glands 8. Vestibulocochlear nerves (VIII) – inner ear 1. Vestibular branch – maintaining balance 2. Cochlear branch - hearing
Cranial Nerves, continued…. . 9. Glossopharyngeal nerves (IX) – tongue and pharynx; swallowing 10. Vagus nerves (X) – 1. Larynx muscles associated with speech and swallowing 2. Supplies muscles of the heart and smooth muscles and glands in thorax and abdomen – Vasovagal response
Cranial Nerves, continued…. . 11. Accessory nerves (XI) – originate in the medulla oblongata AND spinal cord, so has cranial AND spinal branches 1. Cranial branches – join a vagus nerve and carry impulses to muscles of soft palate, pharynx, and larynx 2. Spinal branches – motor impulses to trapezius and sternocleidomastoid muscles 12. Hypoglossal nerves (XII) – motor impulses to tongue
Spinal Nerves • Thirty-one pairs providing 2 -way communication between spinal cord and parts of upper and lower limbs, neck, and trunk • Divided into: 1. 2. 3. 4. 5. – Cervical nerves Thoracic nerves Lumber nerves Sacral nerves Coccygeal nerves Naming and how many of each? ?
Autonomic Nervous System • Two divisions: – Sympathetic division – prepares body for stressful situations – Parasympathetic division • Most active under ordinary conditions • Counterbalances sympathetic division
Cranial Nerves Mnemonic Devices • Naming: O! O! O! There’s The Abercrombie and Fitch. Very Gorgeous and Very Adorable! Hot! • Type of Nerve: Some Say Money Matters, But My Brother Says Big Boobs Matter More.
