1. Anatomy of the Nervous System Structure and Function January 17, 2002 Gross Anatomy

2. Five major divisions of the brain encephalon = “inside the head” w Forebrain Telencephalon Diencephalon w Midbrain Mesencephalon w Hindbrain Metencephalon Myelencephalon (“medulla”)

3. Brains stem w Diencephalon w Mesencephalon w Metencephalon w Myelencephalon

4. Diencephalon w Thalamus top of the brain stem receives sensory signals and sends them on to sensory cortex w Hypothalamus located just below anterior thalamus regulation of motivated behaviors

5. Mesencephalon w Tectum (“roof”) dorsal surface of the brain stem auditory and visual functions w Tegmentum in front of tectum processing pain and sensorimotor functions

6. Metencephalon w Pons (buldge) of the brainstem w Attachment of some cranial nerves

7. Myelencephalon w Also called medulla w Most posterior portion of the brain w Large tracts running from brain to body w Reticular formation (“little net”) sleep, attention, movement, muscle tone reflexes - cardiac, circulatory, respiratory

8. Telencephalon w Greatest growth in higher vertebrates w Hemispheres - right and left w Four lobes in cerebrum frontal temporal parietal occipital

9. Function of Telencephalon w Mediates complex functions initiates voluntary movement interprets sensory input cognitive processes learning speech & language problem solving

10. Cerebral Cortex w Layer of tissue covering cerebrum w Convolutions fissures = furrows central and lateral fissures divide lobes gyri = ridges w Longitudinal fissure-separates hemispheres w Cerebral commissures-connect hemispheres largest = corpus callosum

11. Major Gyri w Precentral gyrus - primary motor area w Postcentral gyrus - body sensations w Superior temporal gyrus - auditory cortex w Cingulate gyrus – emotional, somatic and autonomic fxs

12. Hippocampus (“sea horse”) w Shared by cerebral cortex and limbic system w Located in the medial temporal lobe w Role in learning and memory

13. Function of the Limbic System w Circuit of structures around the thalamus w Regulate motivated behaviors “the four Fs” fleeing feeding fighting sexual behavior

14. Structures of the Limbic System w Amygdala (“almond”) w Hippocampus (“sea horse”) w Fornix (“arc”) w Cingulate cortex (“encircling”) w Septum w Mammillary bodies

15. Function of the Basal Ganglia w Voluntary motor response w Example of dysfunction = Parkinson’s rigidity tremors poor movement initiation

16. Structures of the Basal Ganglia w Amygdala w Striatum (“striped structure”) Caudate (“tail-like”) Putamen w Globus pallidus (“pale globe”)

17. Brain Areas Relevant to Language w Lichtheim-Geschwind Model Broca’s area Wernicke’s area Arcuate fasciculus Angular gyrus

18. Broca’s area w Posterior portion of lower left frontal lobe w Speech and language production

19. Wernicke’s area w Posterior portion of left temporal area w Auditory comprehension

20. Arcuate fasciculus w Pathway that relays nerve impulses between Broca’s and Wernicke’s areas w Connections between sound patterns and production area

21. Angular gyrus w Parietal lobe w Sensory properties of objects are associated with words