ELAINE N. MARIEB EIGHTH EDITION 7 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by Jerry L. Cook, Sam Houston University ESSENTIALS OF HUMAN ANATOMY & PHYSIOLOGY PART B The Nervous System

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Protection of the Central Nervous System  Scalp and skin  Skull and vertebral column  Meninges Figure 7.16a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Protection of the Central Nervous System  Cerebrospinal fluid  Blood brain barrier Figure 7.16a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Meninges  Dura mater  Outer layer – touch, “durable” covering  Arachnoid layer  Middle layer - web-like  Pia mater  Internal layer - clings to brain’s surface

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cerebrospinal Fluid  Similar to blood plasma  Forms a watery cushion to protect the brain  Circulated in arachnoid space, ventricles, and central canal of the spinal cord

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Ventricles and Location of the Cerebrospinal Fluid Figure 7.17a–b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Ventricles and Location of the Cerebrospinal Fluid Figure 7.17c

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Regions of the Brain  Cerebrum  Brain stem  Cerebellum Figure 7.12b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cerebral Hemispheres (Cerebrum)  The surface is made of:  ridges (gyri)  grooves (sulci) Figure 7.13a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lobes of the Cerebrum  Fissures (deep grooves) divide the cerebrum into lobes  Frontal lobe (intellect, motor, creativity, personality)  Parietal lobe (sensory, interpretation)  Occipital lobe (vision)  Temporal lobe (auditory)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lobes of the Cerebrum Figure 7.15a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Somatic sensory – receives impulses from sensory receptors (anterior parietal lobe)  Primary motor – sends impulses to skeletal muscles (posterior frontal lobe)  Broca’s area – involved in our ability to speak (left side….between frontal and temporal lobe)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Sensory and Motor Areas of the Cerebral Cortex Figure 7.14

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum Figure 7.13c

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Layers of the Cerebrum  Gray matter (cortex)  Outer layer  Composed mostly of neuron cell bodies  Cell bodies – processing! Figure 7.13a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Layers of the Cerebrum  White matter  Fiber tracts inside the gray matter  Transfers information!  Example: corpus callosum connects hemispheres Figure 7.13a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Diencephalon  Sits on top of the brain stem  Composed of thalamus, hypothalamus, epithalamus

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Thalamus Thalamus – relays sensory impulses to the correct part of cerebral cortex for interpretation. Hypothalamus – regulates body temperature, water balance and metabolism. Important in drives and emotions (sex, pain, pleasure). Also houses pituitary gland (major hormones) Epithalamus – forms cerebrospinal fluid

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Brain Stem  Attaches to the spinal cord  Parts of the brain stem  Midbrain  Pons  Medulla oblongata

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Midbrain  Mostly composed of tracts of nerve fibers (conducts signals)  Reflex centers for vision and hearing

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Pons  The bulging center part of the brain stem  Mostly composed of fiber tracts for conducting signals  Includes nuclei involved in the control of breathing

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Medulla Oblongata  The lowest part of the brain stem  Merges into the spinal cord  Includes important fiber tracts  Contains control centers for:  Heart rate control  Blood pressure regulation  Breathing  Swallowing  Vomiting

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cerebellum  Two hemispheres with convoluted surfaces  Provides involuntary coordination of body movements