Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

Protection of the Brain The brain is protected by Bones (we will learn later) meninges Cerebrospinal fluid Harmful substances are shielded from the brain by the blood-brain barrier

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Meninges Made of Connective tissue Functions Cover, Protect CNS Enclose, protect blood vessels supplying CNS Contain CSF 3 Layers separated by spaces Dura Mater (external) – sub dural space Arachnoid Mater (middle) – sub arachnoid space (with CSF) Pia Mater (internal)

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings CSF – cerebrospinal fluid Liquid cushion for brain and spinal cord Nourishes brain Removes waste Conducts chemical signals between parts of CNS Produced in Choroid Plexuses: group of capillaries surrounded by ependymal cells

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings pg Parts Cerebrum Diencephalon Brain Stem Cerebellum The Brain

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cerebral Hemispheres and lobes Each hemisphere divided into 4 lobes Frontal Parietal Occipital Temporal Insula (deep to temporal)

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Surface contains gyri and sulci or fissures Longitudinal fissure separates two cerebral hemispheres Central sulcus separates frontal and parietal lobes Lateral sulcus separates the prietal and temporal Transverse sulucus separate the cerebrum and cerebelum Cerebral surface

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Basal nuclei Cerebrum functional regions The cerebrum has three basic regions: cortex, white matter, and basal nuclei

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Structures Caudate Lentiform Putamen Globus Pallidus Organization Input from cortex Project motor to cortex Function Stop, start Monitor movement Inhibit unnecessary movement Basal nuclei

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Head of nucleus caudatus Globus pallidus Putamen

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Commissures – connect corresponding gray areas of the two hemispheres allowing them to work as one unit The largest is the corpus callosum Association fibers – connect different parts of the same hemisphere Projection fibers – enter the hemispheres from lower brain or cord centers Cerebral White Matter

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Adjust ongoing movements on the basis of comparison between arriving sensation to one previously experienced Posture: Balance Equilibrium Fine Tune Movements Timing Rate Range Force Cerebellar Function

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Brainstem: Midbrain, Pons, Medulla Passage of signals between spinal cord and cerebrum *Midbrain: contains cell bodies of CN III, IV *Pons: attachment of CN V, VI, VII *Medulla: attachment of CN VIII, IX, X, XI, XII * * *

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Mesencephalon/midbrain Responsible for vision and auditory reflex Pons function as a “bridge” Nuclei that help control respiration Nuclei and tracts linking the cerebellum with the brain stem, cerebrum and spinal cord Medulla oblongata Connects the brain with the spinal cord Contains relay stations and reflex centers Cardiovascular and respiratory rhythmicity centers Brainstem functions

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Diencephalon Surrounded by cerebral hemispheres Made of 3 Paired Structures Thalamus Processing center for sensory info Hypothalamus Emotion, sleep, memory, temperature, heart rate. Pituitary Gland-hormones Epithalamus Pineal Gland-hormone

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Ventricles Filled with CSF (cerebrospinal fluid) Ventricles continuous w/each other + central canal of spinal cord Lateral Ventricle (#1+2) Cerebral Hemisphere Third Ventricle Diencephalon Interventricular Foramen: connects to lateral ventricle Fourth Ventricle Cerebral Aqueduct: connects 3 rd and 4 th ventricles Connects to central canal of spinal cord & medulla 3 4 lateral

Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings

Sectional anatomy of the spinal cord White matter is myelinated and unmyelinated axons Gray matter is cell bodies, unmyelinated axons and neuroglia Projections of gray matter toward outer surface of cord are horns