Presentation is loading. Please wait.

Presentation is loading. Please wait.

ELAINE N. MARIEB EIGHTH EDITION 7 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by.

Similar presentations


Presentation on theme: "ELAINE N. MARIEB EIGHTH EDITION 7 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by."— Presentation transcript:

1 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

2 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Reflex Arc  Reflex – rapid, predictable, and involuntary responses to stimuli  Reflex arc – direct route from a sensory neuron, to an interneuron, to an effector  All reflex arcs have 5 elements (#ed below) Figure 7.11a

3 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Simple Reflex Arc Figure 7.11b–c

4 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Types of Reflexes and Regulation  Autonomic reflexes  Smooth muscle regulation  Heart and blood pressure regulation  Regulation of glands  Digestive system regulation  Somatic reflexes  Activation of skeletal muscles

5 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Central Nervous System (CNS)  CNS develops from the embryonic neural tube  The neural tube becomes the brain and spinal cord  The opening of the neural tube becomes the ventricles  Four chambers within the brain  Filled with cerebrospinal fluid

6 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Regions of the Brain  Cerebral hemispheres  Diencephalon  Brain stem  Cerebellum  Adult brain weighs a little over 3 pounds Figure 7.12b

7 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Cerebral Hemispheres (Cerebrum)  Paired (left and right) superior parts of the brain  Include more than half of the brain mass Figure 7.13a

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

9 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lobes of the Cerebrum  Fissures (deep grooves) divide the cerebrum into lobes  Single deep fissure (longitudinal fissure) separates the cerebral hemispheres  Surface lobes of the cerebrum named for the cranial bones that lie over them  Frontal lobe  Parietal lobe  Occipital lobe  Temporal lobe

10 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lobes of the Cerebrum Figure 7.13b

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

12 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Somatic sensory area – receives impulses from the body’s sensory receptors (pain, coldness, light touch)  Located in the parietal lobe posterior to central sulcus  Left side of the sensory cortex receives impulses from the right side of the body

13 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Primary motor area – sends impulses to skeletal muscles  Located in the frontal lobe anterior to the central sulcus  Axons of these motor neurons form the corticospinal or pyramidal tract, which descends to the cord

14 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Broca’s area – involved in our ability to speak  Located at the base of the precentral gyrus  Located in only one hemisphere (usually the left)  Damage to this area causes inability to say words properly – know what you want to say but can’t vocalize

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

16 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Cerebral areas involved in special senses  Gustatory area (taste)  Parietal lobe – corner of the central & lateral sulcus  Visual area  Posterior part of the occipital lobe

17 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Auditory area  In the temporal lobe bordering the lateral sulcus  Olfactory area  Deep inside the temporal lobe

18 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Interpretation areas of the cerebrum  Speech/language region  Junction of the temporal, parietal, & occipital lobes  Allows one to sound out words  Usually in only one cerebral hemisphere

19 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Specialized Areas of the Cerebrum  Language comprehension region  Frontal lobes  Word meanings  General interpretation area  Temporal, parietal, & occipital lobes

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

21 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Layers of the Cerebrum  Gray matter  Outer layer (cerebral cortex)  Composed mostly of neuron cell bodies  Highly ridged (convoluted) – gives more surface area for neurons Figure 7.13a

22 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Layers of the Cerebrum  White matter  Fiber tracts (bundles of nerve fibers) inside the gray matter  Carry impulses to & from cerebral cortex Figure 7.13a

23 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Layers of the Cerebrum  Example: corpus callosum connects cerebral hemispheres allowing for communication *Important because some of the critical functional areas are in only one hemisphere

24 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Layers of the Cerebrum  Basal nuclei (basal ganglia) – internal islands of gray matter  Help regulate voluntary motor activities by modifying instructions sent to the skeletal muscles by the primary motor cortex Figure 7.13a

25 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Diencephalon  Sits on top of the brain stem  Enclosed by the cerebral hemispheres  Made of three parts  Thalamus  Hypothalamus  Epithalamus

26 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Diencephalon Figure 7.15

27 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Thalamus  Surrounds the third ventricle  The relay station for sensory impulses upward to the sensory cortex  Transfers impulses to the correct part of the cortex for localization and interpretation by the neurons

28 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Hypothalamus  Under the thalamus  Important autonomic nervous system center  Helps regulate body temperature  Controls water balance  Regulates metabolism

29 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Hypothalamus  An important part of the limbic system (emotions)  The pituitary gland hangs from the anterior floor of the hypothalamus by a slender stalk  Regulates the pituitary gland  Produces 2 of its own hormones

30 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Epithalamus  Forms the roof of the third ventricle  Houses the pineal body (an endocrine gland)  Includes the choroid plexus – forms cerebrospinal fluid

31 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Brain Stem (size of a thumb)  Attaches to the spinal cord  Parts of the brain stem  Midbrain  Pons  Medulla oblongata  Provides pathway for ascending & descending tracts  Basal nuclei of brain stem control breathing & blood pressure

32 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Brain Stem Figure 7.15a

33 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Midbrain  Mostly composed of tracts of nerve fibers  Has two bulging fiber tracts – cerebral peduncles – convey ascending & descending impulses  Has four rounded protrusions – corpora quadrigemina  Reflex centers for vision and hearing

34 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Pons (“bridge”)  The bulging center part of the brain stem  Mostly composed of fiber tracts  Includes nuclei involved in the control of breathing

35 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 important control centers  Heart rate control  Blood pressure regulation  Breathing  Swallowing  Vomiting

36 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Reticular Formation  Diffuse mass of gray matter along the brain stem  Involved in motor control of visceral organs  Reticular activating system plays a role in awake/sleep cycles and consciousness *Damage to this area can result in permanent unconsciousness (coma)

37 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Reticular Formation Figure 7.15b


Download ppt "ELAINE N. MARIEB EIGHTH EDITION 7 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by."

Similar presentations


Ads by Google