Fundamentals of Anatomy &
Physiology
Eleventh Edition
Chapter 14
The Brain and Cranial
Nerves
Lecture Presentation by
Deborah A. Hutchinson
Seattle University
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Introduction to the Brain and Cranial
Nerves
• Adult human brain
– Contains almost 97 percent of body’s nervous tissue
– Average weight is 1.4 kg (3 lb)
– Volume is typically 1200 mL
▪ Ranges from 750 to 2100 mL in functionally normal
individuals
– Brains of males are about 10 percent larger than those
of females
▪ No correlation between brain size and intelligence
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (1 of 14)
Learning Outcome: Name the major brain regions,
vesicles, and ventricles, and describe the locations and
functions of each.
• Regions of the brain
– Cerebrum
– Cerebellum
– Diencephalon
– Brainstem
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.1 An Introduction to Brain
Structures and Functions (Part 1 of 2)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (2 of 14)
• Cerebrum
– Largest part of adult brain
– Controls higher mental functions
▪ Conscious thoughts, intellect, memory, etc.
– Divided into left and right cerebral hemispheres
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (3 of 14)
• Cerebral cortex of cerebrum
– Surface layer of gray matter
– Rounded elevations (gyri) increase surface area
– Gyri are separated by
▪ Shallow depressions (sulci) or
▪ Deep grooves (fissures)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (4 of 14)
• Cerebellum
– Second-largest part of brain
– Coordinates repetitive body movements
– Two hemispheres
– Covered by gray matter (cerebellar cortex)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (5 of 14)
• Diencephalon
– Located under cerebrum and cerebellum
– Thalamus
▪ Relays and processes sensory information
– Hypothalamus is involved with
▪ Emotions
▪ Autonomic function
▪ Hormone production
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (6 of 14)
• Diencephalon
– Pituitary gland
▪ Major endocrine gland
▪ Connected to hypothalamus via infundibulum (stalk)
– Integrates nervous and endocrine systems
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (7 of 14)
• Brainstem
– Relays information between spinal cord and cerebrum
or cerebellum
– Includes
▪ Midbrain
▪ Pons
▪ Medulla oblongata
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (8 of 14)
• Midbrain
– Processes sight, sound, and associated reflexes
– Maintains consciousness
• Pons
– Connects cerebellum to brainstem
– Contains
▪ Tracts (collections of CNS axons)
▪ Relay centers
▪ Nuclei for somatic and visceral motor control
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (9 of 14)
• Medulla oblongata
– Connects brain to spinal cord
– Inferior portion has a narrow central canal
– Relays sensory information
– Regulates autonomic functions
▪ Heart rate, blood pressure, and digestion
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.1 An Introduction to Brain
Structures and Functions (Part 2 of 2)
c) Diencephalon
d) Midbrain
e) Pons
f) Medulla oblongata
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (10 of 14)
• Embryonic development
– Determines organization of brain structures
– Neural tube
▪ Develops into CNS
▪ Rostral portion enlarges to form three primary brain
vesicles
– Prosencephalon (“forebrain”)
– Mesencephalon (“midbrain”)
– Rhombencephalon (“hindbrain”)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (11 of 14)
• Secondary brain vesicles
– Telencephalon
– Diencephalon
– Mesencephalon
– Metencephalon
– Myelencephalon
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (13 of 14)
• Ventricles of the brain
– Each cerebral hemisphere contains one large lateral
ventricle
▪ Separated by medial partition (septum pellucidum)
– Third ventricle in diencephalon
▪ Communicates with each lateral ventricle
▪ Via interventricular foramen
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.1 The Brain (14 of 14)
• Ventricles of the brain
– Fourth ventricle
▪ Extends into medulla oblongata
▪ Joins central canal of spinal cord
▪ Connects with third ventricle
– Via narrow canal in midbrain (cerebral
aqueduct)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.2a Ventricular System
(a) Ventricular system, lateral view. The orientation and extent of the ventricles as they
would appear if the brain were transparent. ATLAS: Plates 10; 12a–c; 13a–e
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.2 b Ventricular System
(b) Ventricular system, anterior view. The orientation and extent of the ventricles as they
would appear if the brain were transparent. ATLAS: Plates 10; 12a–c; 13a–e
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
Learning Outcome: Explain how the brain is protected and
supported, and discuss the formation, circulation, and
function of cerebrospinal fluid.
• Physical protection of the brain
– Bones of the cranium
– Cranial meninges
– Cerebrospinal fluid
• Biochemical isolation
– Blood brain barrier
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Cranial meninges
– Have three layers
▪ Dura mater
▪ Arachnoid mater
▪ Pia mater
– Continuous with spinal meninges
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Cerebrospinal fluid (CSF)
– Surrounds all exposed surfaces of CNS
– Functions to
▪ Support brain
▪ Cushion delicate neural structures
▪ Transport nutrients, chemical messengers, and
wastes
-Produced by choroid plexus
▪ Specialized ependymal cells surround capillaries
▪ Removes waste products from CSF
▪ Adjusts composition of CSF
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.4 Formation and Circulation
of Cerebrospinal Fluid
5 Fingerlike extensions of the arachnoid membrane, called the arachnoid villi, penetrate the meningeal layer of the dura
mater and extend into the superior sagittal sinus. In adults, these extensions form large arachnoid granulations. CSF is
absorbed into the venous circulation at the arachnoid granulations.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Protective function of cranial meninges and CSF
– Dural folds hold brain in position
▪ Protect it from damage that would result from contact
with cranium
– CSF cushions brain against sudden jolts
– Cranial trauma
▪ Head injury resulting from impact with an object
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Blood supply to the brain
– Internal carotid arteries and vertebral arteries
▪ Deliver nutrients and oxygen
– Most blood is removed from dural venous sinuses by
internal jugular veins
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Cerebrovascular diseases
– Disorders that interfere with blood supply to brain
– Cerebrovascular accident (CVA) or stroke
▪ Stops blood flow to a portion of the brain
▪ Affected neurons begin to die within minutes
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Blood brain barrier (BBB)
– Isolates CNS from general circulation
– Formed by network of tight junctions
▪ Between capillary endothelial cells in CNS
– Generally, only lipid-soluble compounds like O 2 , CO 2
steroids, prostaglandins, and small alcohols
▪ Can diffuse into interstitial fluid of CNS
– Astrocytes regulate blood brain barrier by
▪ Releasing chemicals that control permeability of
endothelium
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Blood CSF barrier
– Formed by specialized ependymal cells connected by
tight junctions
▪ That surround capillaries of choroid plexus
– Limits transfer of substances to CSF
– Allows chemical composition of blood and CSF to differ
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.2 Brain Protection and Support
• Breaks in the BBB
– Portions of hypothalamus
▪ Allows hypothalamic hormones into circulation
– Posterior lobe of pituitary gland
▪ Allows ADH and oxytocin into circulation
– Pineal gland
▪ Allows pineal secretions into circulation
– Choroid plexus
▪ Where specialized ependymal cells maintain blood
CSF barrier
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.3 The Medulla Oblongata (1 of 4)
Learning Outcome: Describe the anatomical differences
between the medulla oblongata and the spinal cord, and
identify the main components and functions of the medulla
oblongata.
• Medulla oblongata
– Most inferior part of brainstem
– Coordinates complex autonomic reflexes
– Includes three groups of nuclei
▪ Control visceral functions
▪ Sensory and motor nuclei of CNS
▪ Relay stations for communication between brain
and spinal cord
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.5a The Diencephalon and
Brainstem
(a) Lateral view. The brainstem is made up of the medulla oblongata, pons, and midbrain.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.5b The Diencephalon and
Brainstem
(b) Anterior view. The brainstem is made up of the medulla oblongata, pons, and midbrain.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.5c The Diencephalon and
Brainstem
(c) Posterior view. The brainstem is made up of the medulla oblongata, pons, and midbrain.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.5d The Diencephalon and
Brainstem
(d) Posterior view, cadaver dissection. The brainstem is made up of the medulla oblongata,
pons, and midbrain.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.3 The Medulla Oblongata (2 of 4)
• Reflex centers: autonomic and reflex activity
– Reticular formation
▪ Gray and white matter with embedded nuclei
▪ Regulates autonomic functions
– Cardiovascular centers
▪ Cardiac and vasomotor centers
▪ Control blood flow through peripheral tissues
– Respiratory rhythmicity centers
▪ Set pace for respiratory movements
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.3 The Medulla Oblongata (3 of 4)
• Sensory and motor nuclei of cranial nerves
– Associated with 5 cranial nerves  VIII, IX, X, XI, XII 
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.3 The Medulla Oblongata (4 of 4)
• Relay stations along sensory and motor pathways
– Gracile nucleus and cuneate nucleus
▪ Pass somatic sensory information to thalamus
▪ Tracts leaving nuclei cross to opposite side of brain
at decussation of pyramids
– Solitary nuclei
▪ Receive visceral sensory information
– Inferior olivary complex
▪ Bulk of olivary nuclei creates the olives
▪ Relay information about somatic motor commands
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.6a The Medulla Oblongata
(a) Anterior view. ATLAS: Plates 9a–c; 11c
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.6b The Medulla Oblongata
(b) Posterolateral view. ATLAS: Plates 9a–c; 11c
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.4 The Pons (1 of 1)
Learning Outcome: List the main components of the pons,
and specify the functions of each.
• Pons contains
– Sensory and motor nuclei of cranial nerves
– Nuclei involved with respiration
▪ Apneustic center and pneumotaxic center
– Nuclei and tracts that process and relay information
sent to or from cerebellum
– Ascending, descending, and transverse pontine fibers
▪ Transverse pontine fibers (axons) link nuclei of
pons with opposite cerebellar hemisphere
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.7 The Pons
ATLAS: Plates 9a–c; 11c
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.5 The Midbrain (1 of 2)
Learning Outcome: List the main components of the
midbrain, and specify the functions of each.
• Structures of the midbrain
– Tectum
▪ Two pairs of sensory nuclei (corpora
quadrigemina)
– Superior colliculi (visual)
– Inferior colliculi (auditory)
– Tegmentum
▪ Red nucleus (many blood vessels)
▪ Substantia nigra (pigmented gray matter)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.5 The Midbrain (2 of 2)
• Structures of the midbrain
– Cerebral peduncles
▪ Nerve fiber bundles on ventrolateral surfaces
▪ Contain
– Descending fibers to cerebellum
– Descending motor command fibers
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.8a The Midbrain
(a) A posterior view. The underlying nuclei are colored only on the right. ATLAS: Plates 7b;
9a–c; 11c; 12a,c
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.8b The Midbrain
(b) Posterior view of a cadaver dissection of the diencephalon and brainstem. ATLAS: Plates
7b; 9a–c; 11c; 12a,c
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.8c The Midbrain
(c) A superior view of a transverse section at the level of the midbrain. ATLAS: Plates 7b;
9a–c; 11c; 12a,c
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.6 The Cerebellum (1 of 6)
Learning Outcome: List the main components of the
cerebellum, and specify the functions of each.
• Structures of the cerebellum
– Cerebellar cortex
▪ Gray matter of highly convoluted surface
– Folia
▪ Folds in cerebellar cortex
– Anterior and posterior lobes
▪ Separated by primary fissure
– Cerebellar hemispheres
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.6 The Cerebellum (2 of 6)
• Structures of the cerebellum
– Vermis (“worm”)
▪ Narrow band of cortex
▪ Separates cerebellar hemispheres at midline
– Flocculonodular lobe
▪ Lies above roof of fourth ventricle
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.6 The Cerebellum (3 of 6)
• Structures of the cerebellum
– Purkinje cell layer
▪ Consists of large, branched neuron cell bodies
▪ In cerebellar cortex
▪ Each cell receives input from up to 200,000
synapses
– Arbor vitae (“tree of life”)
▪ Highly branched, internal white matter of cerebellum
▪ Cerebellar nuclei embedded in arbor vitae
– Relay information to Purkinje cells
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.6 The Cerebellum (4 of 6)
• Functions of the cerebellum are to
– Adjust postural muscles
– Program and fine-tune conscious and subconscious
movements
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.6 The Cerebellum (5 of 6)
• Cerebellar peduncles
– Tracts that link cerebellum with brainstem, cerebrum,
and spinal cord leave the cerebellum as
▪ Superior cerebellar peduncles
▪ Middle cerebellar peduncles
▪ Inferior cerebellar peduncles
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.6 The Cerebellum (6 of 6)
• Disorders of the cerebellum
– Ataxia
▪ Disturbance in muscular coordination
▪ Caused by
– Damage from trauma or stroke
– Intoxication (temporary impairment)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.9a The Cerebellum
(Part 1 of 2)
(a) The posterior, superior surface of the cerebellum, showing major anatomical landmarks
and regions
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.9a The Cerebellum
(Part 2 of 2)
(a) The posterior, superior surface of the cerebellum, showing major anatomical landmarks
and regions
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.9b The Cerebellum
(Part 1 of 2)
(b) A sectional view of the cerebellum, showing the arrangement of gray matter and white
matter
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.9b The Cerebellum
(Part 2 of 2)
(b) A sectional view of the cerebellum, showing the arrangement of gray matter and white
matter
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (1 of 7)
Learning Outcome: List the main components of the
diencephalon, and specify the functions of each.
• Diencephalon
– Integrates sensory information with motor commands
– Epithalamus, thalamus, and hypothalamus
– Pineal gland
▪ In posterior portion of epithalamus
▪ Secretes melatonin
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (2 of 7)
• Thalamus
– Filters and relays sensory information
▪ From spinal cord and cranial nerves
▪ To cerebral cortex
– Relays information between basal nuclei and cerebral
cortex
– The third ventricle separates left and right sides
– Interthalamic adhesion
▪ Projection of gray matter
▪ Extends into third ventricle on each side
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (3 of 7)
• Thalamic nuclei
– Relay sensory information to basal nuclei and cerebral
cortex
• Five groups of thalamic nuclei
– Anterior nuclei of thalamus
▪ Part of limbic system (emotions)
– Medial nuclei of thalamus
▪ Provide awareness of emotional states
– Ventral nuclei of thalamus
▪ Relay sensory information to cerebral cortex
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (4 of 7)
• Five groups of thalamic nuclei
– Dorsal nuclei of thalamus
▪ Pulvinar nuclei (sensory)
– Geniculate bodies
▪ Lateral geniculate body (visual)
▪ Medial geniculate body (auditory)
– Affects emotional states
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.10a The Thalamus
(a) A lateral view of the brain, color coded to indicate the regions that receive input from the
thalamic nuclei shown in part b
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (5 of 7)
• Hypothalamus
– Mammillary bodies
▪ Control reflex eating movements
– Infundibulum
▪ A narrow stalk
▪ Connects hypothalamus to pituitary gland
– Tuber cinereum
▪ Between infundibulum and mammillary bodies
▪ Produces hormones that affect pituitary gland
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (6 of 7)
• Eight functions of hypothalamus
– Secretes ADH (supra-optic nucleus) and
oxytocin (paraventricular nucleus)
– Regulates body temperature
▪ Pre-optic area
– Controls autonomic function
– Coordinates voluntary and autonomic functions
– Coordinates nervous and endocrine systems
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.7 The Diencephalon (7 of 7)
• Eight functions of hypothalamus
– Regulates circadian rhythms (day–night cycles)
▪ Suprachiasmatic nucleus
– Subconscious control of skeletal muscle
– Produces emotions and behavioral drives
▪ Feeding center (hunger)
▪ Thirst center (thirst)
▪ Satiety center (regulates food intake)
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.8 The Limbic System (1 of 3)
Learning Outcome: Identify the main components of the
limbic system, and specify the locations and functions of
each.
• Limbic system
– Functional grouping that
▪ Establishes emotional states
▪ Links conscious functions of cerebral cortex with
autonomic functions of brainstem
▪ Facilitates memory storage and retrieval
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.8 The Limbic System (2 of 3)
• Components of the limbic system
– Limbic lobe of cerebral hemisphere
▪ Cingulate gyrus
▪ Dentate gyrus
▪ Parahippocampal gyrus
▪ Hippocampus
– Amygdaloid body
▪ Acts as interface between the limbic system,
cerebrum, and various sensory systems
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.8 The Limbic System (3 of 3)
• Components of the limbic system
– Fornix
▪ Tract of white matter
▪ Connects hippocampus with hypothalamus
– Anterior nuclei of thalamus
▪ Relay information from mammillary body to cingulate
gyrus
– Reticular formation
▪ Alertness, excitement, lethargy, and sleep
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.12a The Limbic System
(a) A diagrammatic sagittal section through the cerebrum, showing the cortical areas
associated with the limbic system. The parahippocampal gyus is shown as though
transparent to make deeper limbic components visible.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.12b The Limbic System
(b) A three-dimensional reconstruction of the limbic system, showing the relationships
among the major components.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (1 of 25)
• Learning Outcome: Identify the major anatomical subdivisions
and functions of the cerebrum, and discuss the origin and
significance of the major types of brain waves seen in an
electroencephalogram.
• Cerebrum
– Largest part of brain
– Controls all conscious thoughts and intellectual functions
– Processes somatic sensory and motor information
– Gray matter
▪ In cerebral cortex and basal nuclei
– White matter
▪ Deep to cerebral cortex
▪ Around basal nuclei
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (2 of 25)
• Structures of the cerebrum
– Gyri of cerebral cortex
▪ Increase surface area available for cortical neurons
– Longitudinal cerebral fissure
▪ Separates cerebral hemispheres
– Lobes
▪ Regions of hemispheres
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (3 of 25)
• Structures of the cerebrum
– Central sulcus divides
▪ Anterior frontal lobe from posterior parietal lobe
– Precentral gyrus of frontal lobe
▪ Forms anterior border of central sulcus
– Postcentral gyrus of parietal lobe
▪ Forms posterior border of central sulcus
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (4 of 25)
• Structures of the cerebrum
– Lateral sulcus
▪ Separates frontal lobe from temporal lobe
– Insula (“island” of cortex)
▪ Lies medial to lateral sulcus
– Parieto-occipital sulcus
▪ Separates parietal lobe from occipital lobe
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.13a The Brain in Lateral
View
(a) Lateral view, cadaver brain. ATLAS: Plates 11a,b; 13b–e; 14a–d
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.13b The Brain in Lateral
View
(b) Lateral view. ATLAS: Plates 11a,b; 13b–e; 14a–d
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.13c The Brain in Lateral
View
(c) Retractors along the lateral sulcus showing the insula. ATLAS: Plates 11a,b; 13b–e;
14a–d
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.13d The Brain in Lateral
View
(d) Midsagittal section. ATLAS: Plates 11a,b; 13b–e; 14a–d
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (5 of 25)
• White matter of the cerebrum
– Association fibers
▪ Form connections within one hemisphere
▪ Arcuate fibers
– Short fibers
– Connect one gyrus to another
▪ Longitudinal fasciculi
– Longer bundles
– Connect frontal lobe to other lobes in same
hemisphere
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (6 of 25)
• White matter of the cerebrum
– Commissural fibers
▪ Bands of fibers connecting two hemispheres
▪ Corpus callosum
▪ Anterior commissure
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (7 of 25)
• White matter of the cerebrum
– Projection fibers
▪ Link cerebral cortex to diencephalon, brainstem,
cerebellum, and spinal cord
▪ Pass through diencephalon
▪ Internal capsule
– All ascending and descending projection fibers
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.14a Fibers of the White
Matter of the Cerebrum
(a) Lateral view
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.14b Fibers of the White
Matter of the Cerebrum
(b) Anterior view
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (8 of 25)
• Basal nuclei
– Masses of gray matter
– Embedded in white matter of cerebrum
– Direct subconscious activities
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (9 of 25)
• Basal nuclei
– Caudate nucleus
▪ Large head and slender, curving tail
– Lentiform nucleus
▪ Putamen (lateral)
▪ Globus pallidus (medial)
– Claustrum
▪ Thin layer of gray matter close to putamen
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.15a The Basal Nuclei
(a) The relative positions of the basal nuclei in the intact brain, lateral view. ATLAS: Plates
11c; 13a,f
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.15c The Basal Nuclei
(c) Frontal section. ATLAS: Plates 11c; 13a,f
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (10 of 25)
• Functions of basal nuclei
– Subconscious control of skeletal muscle tone
– Coordination of learned movement patterns (walking,
lifting)
• Parkinson’s disease
– Symptoms are caused by increased activity of basal
nuclei
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (11 of 25)
• Functional principles of the cerebrum
– Cortex of each cerebral hemisphere
▪ Receives somatosensory information from
▪ And sends motor commands to
▪ The opposite side of the body
– Correspondence between a specific function and a
specific area of the cerebral cortex is imprecise
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (12 of 25)
• Central sulcus separates motor and sensory areas
• Motor areas
– Primary motor cortex
▪ Surface of precentral gyrus
– Pyramidal cells
▪ Neurons of primary motor cortex
• Sensory areas
– Primary somatosensory cortex
▪ Surface of postcentral gyrus
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (13 of 25)
• Special sensory cortices
– Visual cortex
▪ Receives visual information
– Auditory cortex
▪ Receives information about hearing
– Olfactory cortex
▪ Receives information about smell
– Gustatory cortex
▪ Receives information from taste receptors
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (14 of 25)
• Association areas
– Connected to sensory and motor regions of cortex
– Interpret incoming data or coordinate a motor response
• Premotor cortex
– Also called somatic motor association area
– Coordinates learned movements
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (15 of 25)
• Sensory association areas
– Somatosensory association cortex
▪ Monitors activity in primary somatosensory cortex
▪ Example: it recognizes touch
– Visual association area
▪ Interprets activity in visual cortex
– Auditory association area
▪ Monitors auditory cortex
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.16a Motor, Sensory, and
Association Areas of the Cerebral
Cortex
(a) Major anatomical landmarks on the surface of the left cerebral hemisphere. The lateral
sulcus has been pulled apart to expose the insula.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Table 14.3 The Cerebral Cortex
Lobe/Area
FRONTAL LOBE
Primary motor cortex
PARIETAL LOBE
Primary somatosensory
cortex
OCCIPITAL LOBE
Visual cortex
TEMPORAL LOBE
Auditory cortex and
olfactory
cortex
ALL LOBES
Motor, sensory,
somatosensory, and
association areas
Function
blank
Voluntary control of skeletal muscles
blank
Conscious perception of touch, pressure, pain, vibration, taste, and
temperature
blank
Conscious perception of visual stimuli
blank
Conscious perception of auditory (hearing) and olfactory (smell)
stimuli
blank
Integration and processing of sensory data; processing and
initiation of motor activities
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (16 of 25)
• Integrative centers
– In lobes and cortical areas of both cerebral hemispheres
– Receive information from association areas
– Direct complex motor activities
– Perform analytical functions
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (17 of 25)
• Wernicke’s area
– Language comprehension
– Primarily associated with left cerebral hemisphere
– Receives information from sensory association areas
– Coordinates access to visual and auditory memories
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (18 of 25)
• Broca’s area (motor speech area)
– Speech production
– Primarily associated with left cerebral hemisphere
– Regulates patterns of breathing and vocalization
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (19 of 25)
• Prefrontal cortex of frontal lobe
– Coordinates information relayed from all cortical
association areas
– Performs abstract intellectual functions
▪ Example: predicting consequences of actions
– Prefrontal lobotomy
▪ Used to “cure” mental illnesses in mid-20th century
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Figure 14.16b Motor, Sensory, and
Association Areas of the Cerebral
Cortex
(b) The left hemisphere generally contains the specialized language areas. The prefrontal
cortex of each hemisphere is involved with conscious intellectual functions.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (20 of 25)
• Hemispheric lateralization
– Functional differences between left and right cerebral
hemispheres
▪ Each performs certain functions that are not
ordinarily performed by the opposite hemisphere
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (21 of 25)
• Left cerebral hemisphere
– Reading, writing, and math
– Speech and language
– Decision making
• Right cerebral hemisphere
– Analyzes sensory information
▪ Example: touch, smell, sight, taste
– Recognition of faces and voice inflections
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (22 of 25)
• Brain activity
– Assessed with an electroencephalogram (EEG)
▪ Electrodes are placed on brain or skull
▪ Electrical patterns (brain waves) are observed
• Types of typical brain waves
– Alpha waves
– Beta waves
– Theta waves
– Delta waves
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
14.9 The Cerebrum (25 of 25)
• Synchronization of electrical activity between hemispheres
– Achieved through a “pacemaker” mechanism
– Desynchronization may result from injury or tumor
• Seizure
– A temporary cerebral disorder
– Accompanied by changes in electrical activity
– Symptoms depend on region of cortex affected
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved
Copyright
This work is protected by United States copyright laws and is
provided solely for the use of instructors in teaching their
courses and assessing student learning. Dissemination or sale of
any part of this work (including on the World Wide Web) will
destroy the integrity of the work and is not permitted. The work
and materials from it should never be made available to students
except by instructors using the accompanying text in their
classes. All recipients of this work are expected to abide by these
restrictions and to honor the intended pedagogical purposes and
the needs of other instructors who rely on these materials.
Copyright © 2018, 2015, 2012 Pearson Education, Inc. All Rights Reserved