1 / 28

Anatomy & Physiology

Anatomy & Physiology. Part 2: Nervous System. The Brain:. ~100 billion multipolar neurons 3 major components: The cerebrum largest part (associated with sensory & motor functions, higher mental functions) The cerebellum (voluntary muscle movement & coordination)

jlanghorne
Download Presentation

Anatomy & Physiology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Anatomy & Physiology Part 2: Nervous System

  2. The Brain: • ~100 billion multipolar neurons • 3 major components: • The cerebrumlargest part (associated with sensory & motor functions, higher mental functions) • The cerebellum(voluntary muscle movement & coordination) • The brain stem(connects & regulates viscera) Another part of the brain is the diencephalon. This is also associated with sensory functions.

  3. http://www.google.com/imgres

  4. Cerebrum: • There are 2 cerebral hemispheres. This is collectively called the cerebrum. • Gyriare ridges; sulciare grooves. • Fissuresare deep grooves • Fissures divide the cerebrum into lobes. http://www.google.com/imgres

  5. The corpus callosum is a “bridge” of nerve fibers that connect the 2 hemispheres. • The hemispheres generally mirror each other.

  6. Cerebrum Lobes: These are named for the bones they are under. • Frontal lobe • Parietal lobe • Temporal lobe • Occipital lobe • Insula

  7. There are 3 main areas of the cerebrum: • Cerebral Cortex • White Matter • Basal Nuclei

  8. Cerebrum: Cerebral Cortex: • Functions: speech, memory, logic, emotional responses, & voluntary movement The cortex includes: • Broca’s area: vocalization/formation of words • Speech area: language comprehension (meanings of words)

  9. http://www.google.com/imgres

  10. Cerebrum: White Matter: Basal Nuclei: a.k.a. basal ganglia Gray matter Regulate voluntary motor functions • Contains nerve tracts that allow communication to occur between hemispheres and brain stem

  11. Diencephalon: • It contains the thalamus, hypothalamus, optic tracts pituitary gland, mammillary gland & pineal gland. • The thalamus is the central region of message relays; receiving all sensory info (except smell) & transmitting the signals to the appropriate location. • It produces awareness of sensations. http://www.google.com/imgres

  12. The hypothalamusmaintains homeostasis & links the NS to the endocrine system. It regulates: • Heart rate & blood pressure • Body temperature • Water & electrolyte balance • Hunger & body weight • Stomach & intestinal secretions & movement • Sleep & wakefulness • Production of stimulants for the pituitary gland

  13. Diencephalon: • The hypothalamus includes the limbic system and controls emotional responses & expression; as a result, it guides behavior to increase the chance of survival. Other glands part of the Diencephalon: • Pituitary gland (hormones) • Pineal gland (sleep regulation) • Choroid plexuses (capillaries that secrete CSF)

  14. Brain Stem: • Connects the spinal cord to the cerebrum • Includes the midbrain, pons & medulla oblongata • The midbraincontains reflex centers (visual & auditory) Midbrain http://www.google.com/imgres

  15. The pons is between stem & oblongata; relays sensory impulses & regulates rate & depth of breath. • The medulla oblongata is below the pons • The medulla oblongata is associated with coughing, sneezing, swallowing & vomiting reflexes. • It controls heart rate, blood pressure, and breathing

  16. The reticular formation is a network of nerve fibers that are throughout the midbrain, pons & medulla oblongata. • This regulates wakefulness (increased activity increases awareness; decreased activity induces sleep). • If this is injured, this causes unconsciousness; if the person cannot be aroused, a comatose state (coma) results.

  17. Cerebellum: • Integrates & coordinates sensory info & skeletal muscles; helps to maintain posture. • Injury to this area will cause tremors (involuntary movements), inaccurate movements, staggering walk, muscle tone loss or equilibrium disturbance.

  18. Protection of CNS: Meninges • The CNS is surrounded by bones, membranes & fluids (skull contains the cranial cavity which contains the brain, etc.). • The membranes of the CNS are themeninges (between bones & soft tissues). • These protect the brain & spinal cord. • There are 3 layers to the meninges:dura mater, arachnoid mater, & pia mater.

  19. http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19080.jpghttp://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19080.jpg

  20. Meninges: Dura Mater: Arachnoid Mater: Thin membrane without a blood supply Between dura mater & pia mater Covers brain & spinal cord • outermost layer • found within the cranial cavity, surrounds skull bones, & extends inward between brain lobes • Surrounds the spinal cord & ends as a sac right below the cord (but is not attached to the vertebrate).

  21. Between the arachnoid mater & pia mater is thesubarachnoid space. The cerebrospinal fluid (CSF)is contained here. • This is a clear watery fluid that bathes the brain & spinal cord. Pia Mater: • The innermost layer of the meninges • Covers the brain & spinal cord and follows their surfaces closely

  22. Spinal Cord: • This is a nerve column that goes from the brain into the vertebral canal. • Consists of 31 segments & 31 pairs of spinal nerves • There are 2 enlargements: the cervical enlargementcontains the nerves for the upper limbs; the lumbar enlargementcontains the nerves for the lower limbs. http://www.google.com/imgres

  23. Spinal Cord with Meninges: http://www.google.com/imgres

  24. PNS: Cranial Nerves: • There are 12 pairs of cranial nerves: 1. Olfactory nerves (I):sense of smell 2. Optic nerves(II):vision (eyes to brain) 3. Oculomotor nerves (III):eye muscle movement (somatic & autonomic) 4. Trochlear nerves (IV):eye movement; smallest cranial nerves 5. Trigeminal nerves (V):contain ophthalmic, maxillary, & mandibular nerves; mixed nerves; largest cranial nerves.

  25. 6. Abducens nerves (VI):aids in eye muscle movement 7. Facial nerves (VII): taste receptors; stimulate salivary & tear gland secretions (autonomic) 8. Vestibulocochlear nerves (VIII): maintain equilibrium & enable hearing (ear) 9. Glossopharyngeal nerves (IX): swallowing; mixed nerves; associated with the tongue & pharynx. 10. Vagus nerves (X): speech & swallowing; mixed (autonomic & somatic) 11. Accessory nerves (XI):cranial & spinal 12. Hypoglossal nerves (XII): tongue, speaking, chewing & swallowing. See textbook for summary of cranial nerves.

  26. PNS: Spinal Nerves: • Come from the spinal cord • Grouped according to their location: • Cervical nerves (#C1 to C8): 8 pairs • Thoracic nerves (#T1 to T12): 12 pairs • Lumbar nerves (#L1 to L5): 5 pairs • Sacral nerves (#S1 to S5): 5 pairs • Coccygeal nerves (Co): 1 pair • See textbook summary of these spinal nerves.

  27. Autonomic Nervous System: • Functions independently (autonomous), meaning without conscious thought • Controls visceral functions • Contains the parasympathetic & sympathetic divisions • The parasympathetic division functions during restful conditions while thesympathetic division functions during emergency, stressful & energy spending situations.

  28. Look up in text or online! • Know the following: Huntington’s Disease, Parkinson’s Disease, Ataxia, Meningitis, Encephalitis, Hydrocephalus, Blood brain barrier, Concussion, Contusion, Intracranial hemorrhage, cerebral edema, CVA, hemiplegia, TIA, Cerebral palsy, Spina bifida, and Senility

More Related