Chapter 7 Structural Overview of Major Brain Regions Pages 239-252 Expect to see most of these structures in your brain dissection

Regions of the Brain Cerebral hemispheres (cerebrum) Diencephalon Brain stem Cerebellum Ventricles © 2015 Pearson Education, Inc.

Figure 7.12b Development and regions of the human brain. Cerebral hemisphere Diencephalon Cerebellum Brain stem (b) Adult brain

Table 7.1 Functions of Major Brain Regions (1 of 2)

Table 7.1 Functions of Major Brain Regions (2 of 2)

Cerebrum Two hemispheres (left & right) comprise the superior parts of the brain Includes more than half of the brain mass The longitudinal fissure divides the hemispheres Surface has ridges (gyri) and grooves (sulci) (pg. 242) © 2015 Pearson Education, Inc.

Parts of each hemisphere Three layers of each cerebral hemisphere Cerebral Cortex (gray matter) Cerebral White matter Basal nuclei (deep pockets of gray matter)

Layers of the Cerebral Hemispheres Gray matter: outer layer in the cerebral cortex; composed mostly of neuron cell bodies (gray designates unmyelinated fibers) White matter: fiber tracts deep to the gray matter Carry impulses to/from cortex also known as commissures Corpus callosum (large fiber tract) connects hemispheres (white designates myelinated fibers) Basal nuclei (ganglia): nerve cell bodies that form islands of gray matter buried deep within the white matter © 2015 Pearson Education, Inc.

Figure 7.13a Left lateral view of the brain. Precentral gyrus Central sulcus Postcentral gyrus Frontal lobe Parietal lobe Parieto-occipital sulcus (deep) Lateral sulcus Occipital lobe Temporal lobe Cerebellum Pons Medulla oblongata Cerebral cortex (gray matter) Spinal cord Gyrus Sulcus Cerebral white matter Fissure (a deep sulcus) (a)

Commissural fibers (corpus callosum) Lateral ventricle Figure 7.15 Frontal section of the brain showing commissural, association, and projection fibers running through the cerebrum and the lower CNS. Longitudinal fissure Association fibers Superior Commissural fibers (corpus callosum) Lateral ventricle Corona radiata Basal nuclei (basal ganglia) Fornix Internal capsule Thalamus Third ventricle Projection fibers Pons Medulla oblongata

Lobes of each hemisphere Fissures (deep grooves) further divide the cerebral hemispheres into four lobes Each lobe coincides with its respective cranial bone Frontal lobe Parietal lobe Occipital lobe Temporal lobe © 2015 Pearson Education, Inc.

Figure 7.13b Left lateral view of the brain. Parietal lobe Left cerebral hemisphere Frontal lobe Occipital lobe Temporal lobe Cephalad Cerebellum Caudal Brain stem (b)

Diencephalon Sits on top of the brain stem Cerebral hemispheres wrap around it Three parts: Thalamus: surrounds the third ventricle Hypothalamus: lies under the thalamus Epithalamus: roof of third ventricle © 2015 Pearson Education, Inc.

Figure 7.12b Development and regions of the human brain. Cerebral hemisphere Diencephalon Cerebellum Brain stem (b) Adult brain

Figure 7.16a Diencephalon and brain stem structures. Cerebral hemisphere Corpus callosum Third ventricle Choroid plexus of third ventricle Occipital lobe of cerebral hemisphere Thalamus (encloses third ventricle) Anterior commissure Pineal gland (part of epithalamus) Hypothalamus Corpora quadrigemina Optic chiasma Cerebral aqueduct Midbrain Pituitary gland Cerebral peduncle Mammillary body Fourth ventricle Pons Choroid plexus Medulla oblongata Cerebellum Spinal cord (a)

Regions of the Brain: Brain Stem Attaches to the spinal cord Three parts: Midbrain: connects 3rd and 4th ventricles Pons: solely a collection of nerve fiber tracts Medulla oblongata: nerve fiber tracts; homeostatic fx. © 2015 Pearson Education, Inc.

Figure 7.16a Diencephalon and brain stem structures. Cerebral hemisphere Corpus callosum Third ventricle Choroid plexus of third ventricle Occipital lobe of cerebral hemisphere Thalamus (encloses third ventricle) Anterior commissure Pineal gland (part of epithalamus) Hypothalamus Corpora quadrigemina Optic chiasma Cerebral aqueduct Midbrain Pituitary gland Cerebral peduncle Mammillary body Fourth ventricle Pons Choroid plexus Medulla oblongata Cerebellum Spinal cord (a)

Regions of the Brain: Cerebellum Two hemispheres Convoluted (folded/twisted) surfaces Each hemisphere has: Outer layer: gray matter Inner layer: white matter Called the arbor vitae because of its branched tree-like appearance © 2015 Pearson Education, Inc.

Figure 7.16a Diencephalon and brain stem structures. Cerebral hemisphere Corpus callosum Third ventricle Choroid plexus of third ventricle Occipital lobe of cerebral hemisphere Thalamus (encloses third ventricle) Anterior commissure Pineal gland (part of epithalamus) Hypothalamus Corpora quadrigemina Optic chiasma Cerebral aqueduct Midbrain Pituitary gland Cerebral peduncle Mammillary body Fourth ventricle Pons Choroid plexus Medulla oblongata Cerebellum Spinal cord (a) This midsagittal section shows the gray matter outlining the arbor vitae (white)

Ventricles and cerebrospinal fluid Four ventricles in the brain; central canal of spinal cord Ventricles create a system for distribution of cerebrospinal fluid (CSF) to bathe nervous tissue CSF: provides a cushion for the nervous tissue Is formed from blood by choroid plexuses, clusters of capillaries in each ventricle Is composed of proteins, sugars, few white blood cells, and NO red blood cells