Language AreasLanguage Areas

Located in a large area surrounding the left (or Located in a large area surrounding the left (or language-dominant) lateral sulcuslanguage-dominant) lateral sulcus

Major parts and functions:Major parts and functions: Wernicke’s area –sounding out unfamiliar wordsWernicke’s area –sounding out unfamiliar words Broca’s area – speech preparation and productionBroca’s area – speech preparation and production Lateral prefrontal cortex – language Lateral prefrontal cortex – language

comprehension and word analysiscomprehension and word analysis Lateral and ventral temporal lobe – coordinate Lateral and ventral temporal lobe – coordinate

auditory and visual aspects of languageauditory and visual aspects of language

General (Common) General (Common) Interpretation AreaInterpretation Area

Ill-defined region including parts of the Ill-defined region including parts of the temporal, parietal, and occipital lobestemporal, parietal, and occipital lobes

Found in one hemisphere, usually the leftFound in one hemisphere, usually the left Integrates incoming signals into a single Integrates incoming signals into a single

thoughtthought Involved in processing spatial relationshipsInvolved in processing spatial relationships

Visceral Association AreaVisceral Association Area

Located in the cortex of the insulaLocated in the cortex of the insula Involved in conscious perception of visceral Involved in conscious perception of visceral

sensationssensations

Lateralization of Cortical Lateralization of Cortical FunctionFunction

Lateralization – each hemisphere has abilities Lateralization – each hemisphere has abilities not shared with its partnernot shared with its partner

Cerebral dominance – designates the Cerebral dominance – designates the hemisphere dominant for languagehemisphere dominant for language

Left hemisphere – controls language, math, Left hemisphere – controls language, math, and logicand logic

Right hemisphere – controls visual-spatial Right hemisphere – controls visual-spatial skills, emotion, and artistic skillsskills, emotion, and artistic skills

Cerebral White MatterCerebral White Matter

Consists of deep myelinated fibers and their Consists of deep myelinated fibers and their tractstracts

It is responsible for communication between: It is responsible for communication between: The cerebral cortex and lower CNS center, and The cerebral cortex and lower CNS center, and

areas of the cerebrumareas of the cerebrum

Cerebral White MatterCerebral White Matter

Types include:Types include: Commissures – connect corresponding gray areas Commissures – connect corresponding gray areas

of the two hemispheresof the two hemispheres Association fibers – connect different parts of the Association fibers – connect different parts of the

same hemispheresame hemisphere Projection fibers – enter the hemispheres from Projection fibers – enter the hemispheres from

lower brain or cord centerslower brain or cord centers

Fiber Tracts in White MatterFiber Tracts in White Matter

Figure 12.10a

Fiber Tracts in White MatterFiber Tracts in White Matter

Figure 12.10b

Basal NucleiBasal Nuclei

Masses of gray matter found deep within the Masses of gray matter found deep within the cortical white mattercortical white matter

The corpus striatum is composed of three partsThe corpus striatum is composed of three parts Caudate nucleusCaudate nucleus Lentiform nucleus – composed of the putamen and Lentiform nucleus – composed of the putamen and

the globus pallidusthe globus pallidus Fibers of internal capsule running between and Fibers of internal capsule running between and

through caudate and lentiform nucleithrough caudate and lentiform nuclei

Basal NucleiBasal Nuclei

Figure 12.11a

Basal NucleiBasal Nuclei

Figure 12.11b

Functions of Basal NucleiFunctions of Basal Nuclei

Though somewhat elusive, the following are Though somewhat elusive, the following are thought to be functions of basal nucleithought to be functions of basal nuclei Influence muscular activity Influence muscular activity Regulate attention and cognitionRegulate attention and cognition Regulate intensity of slow or stereotyped Regulate intensity of slow or stereotyped

movementsmovements Inhibit antagonistic and unnecessary movementInhibit antagonistic and unnecessary movement

DiencephalonDiencephalon

Central core of the forebrainCentral core of the forebrain Consists of three paired structures – thalamus, Consists of three paired structures – thalamus,

hypothalamus, and epithalamushypothalamus, and epithalamus Encloses the third ventricleEncloses the third ventricle

DiencephalonDiencephalon

Figure 12.12

ThalamusThalamus

Paired, egg-shaped masses that form the Paired, egg-shaped masses that form the superolateral walls of the third ventriclesuperolateral walls of the third ventricle

Connected at the midline by the intermediate Connected at the midline by the intermediate massmass

Contains four groups of nuclei – anterior, Contains four groups of nuclei – anterior, ventral, dorsal, and posteriorventral, dorsal, and posterior

Nuclei project and receive fibers from the Nuclei project and receive fibers from the cerebral cortexcerebral cortex

ThalamusThalamus

Figure 12.13a

Thalamic FunctionThalamic Function

Sensual afferent impulses converge and Sensual afferent impulses converge and synapse in the thalamussynapse in the thalamus

Impulses of similar function are sorted out, Impulses of similar function are sorted out, edited, and relayed as a groupedited, and relayed as a group

All inputs ascending to the cerebral cortex All inputs ascending to the cerebral cortex pass through the thalamuspass through the thalamus

Mediates sensation, motor activities, cortical Mediates sensation, motor activities, cortical arousal, learning, and memoryarousal, learning, and memory

HypothalamusHypothalamus

Located below the thalamus, it caps the brainstem and Located below the thalamus, it caps the brainstem and forms the inferolateral walls of the third ventricleforms the inferolateral walls of the third ventricle

Mammillary bodiesMammillary bodies Small, paired nuclei bulging anteriorly from the Small, paired nuclei bulging anteriorly from the

hypothalamushypothalamus Relay station for olfactory pathwaysRelay station for olfactory pathways

Infundibulum – stalk of the hypothalamus; connects Infundibulum – stalk of the hypothalamus; connects to the pituitary glandto the pituitary gland Main visceral control center of the bodyMain visceral control center of the body

Hypothalamic NucleiHypothalamic Nuclei

Figure 12.13b

Hypothalamic FunctionHypothalamic Function

Regulates blood pressure, rate and force of Regulates blood pressure, rate and force of heartbeat, digestive tract motility, rate and heartbeat, digestive tract motility, rate and depth of breathing, and many other visceral depth of breathing, and many other visceral activitiesactivities

Perception of pleasure, fear, and ragePerception of pleasure, fear, and rage Maintains normal body temperatureMaintains normal body temperature Regulates feelings of hunger and satiety Regulates feelings of hunger and satiety Regulates sleep and the sleep cycleRegulates sleep and the sleep cycle

Endocrine Functions of the Endocrine Functions of the HypothalamusHypothalamus

Releasing hormones control secretion of Releasing hormones control secretion of hormones by the anterior pituitaryhormones by the anterior pituitary

The supraoptic and paraventricular nuclei The supraoptic and paraventricular nuclei produce ADH and oxytocinproduce ADH and oxytocin

EpithalamusEpithalamus

Most dorsal portion of the diencephalon; forms Most dorsal portion of the diencephalon; forms roof of the third ventricleroof of the third ventricle

Pineal gland – extends from the posterior Pineal gland – extends from the posterior border and secretes melatoninborder and secretes melatonin Melatonin – a hormone involved with sleep Melatonin – a hormone involved with sleep

regulation, sleep-wake cycles, and moodregulation, sleep-wake cycles, and mood Choroid plexus – a structure that secretes Choroid plexus – a structure that secretes

cerebral spinal fluid (CSF)cerebral spinal fluid (CSF)

EpithalamusEpithalamus

Figure 12.12

Human Brain: Ventral AspectHuman Brain: Ventral Aspect

Figure 12.14

Brain StemBrain Stem

Consists of three regions – midbrain, pons, and Consists of three regions – midbrain, pons, and medulla oblongatamedulla oblongata

Similar to spinal cord but contains embedded Similar to spinal cord but contains embedded nucleinuclei

Controls automatic behaviors necessary for Controls automatic behaviors necessary for survivalsurvival

Provides the pathway for tracts between higher Provides the pathway for tracts between higher and lower brain centersand lower brain centers

Associated with 10 of the 12 pairs of cranial Associated with 10 of the 12 pairs of cranial nervesnerves

Brain StemBrain Stem

Figure 12.15a

Brain StemBrain Stem

Figure 12.15b

Brain StemBrain Stem

Figure 12.15c

MidbrainMidbrain

Located between the diencephalon and the Located between the diencephalon and the ponspons

Midbrain structures include:Midbrain structures include: Cerebral peduncles – two bulging structures that Cerebral peduncles – two bulging structures that

contain descending pyramidal motor tractscontain descending pyramidal motor tracts Cerebral aqueduct – hollow tube that connects the Cerebral aqueduct – hollow tube that connects the

third and fourth ventriclesthird and fourth ventricles Various nucleiVarious nuclei

Midbrain NucleiMidbrain Nuclei

Nuclei that control cranial nerves III Nuclei that control cranial nerves III (oculomotor) and IV (trochlear)(oculomotor) and IV (trochlear)

Corpora quadrigemina – four domelike Corpora quadrigemina – four domelike protrusions of the dorsal midbrainprotrusions of the dorsal midbrain

Superior colliculi – visual reflex centersSuperior colliculi – visual reflex centers

Midbrain NucleiMidbrain Nuclei

Inferior colliculi – auditory relay centersInferior colliculi – auditory relay centers Substantia nigra – functionally linked to basal Substantia nigra – functionally linked to basal

nucleinuclei Red nucleus – largest nucleus of the reticular Red nucleus – largest nucleus of the reticular

formation; red nuclei are relay nuclei for some formation; red nuclei are relay nuclei for some descending motor pathwaysdescending motor pathways

Midbrain NucleiMidbrain Nuclei

Figure 12.16a

PonsPons

Bulging brainstem region between the Bulging brainstem region between the midbrain and the medulla oblongatamidbrain and the medulla oblongata

Forms part of the anterior wall of the fourth Forms part of the anterior wall of the fourth ventricleventricle

Fibers of the pons:Fibers of the pons: Connect higher brain centers and the spinal cordConnect higher brain centers and the spinal cord Relay impulses between the motor cortex and the Relay impulses between the motor cortex and the

cerebellumcerebellum

PonsPons

Origin of cranial nerves V (trigeminal), VI Origin of cranial nerves V (trigeminal), VI (abducens), and VII (facial)(abducens), and VII (facial)

Contains nuclei of the reticular formationContains nuclei of the reticular formation

PonsPons

Figure 12.16b

Medulla OblongataMedulla Oblongata

Most inferior part of the brain stemMost inferior part of the brain stem Along with the pons, forms the ventral wall of Along with the pons, forms the ventral wall of

the fourth ventriclethe fourth ventricle Contains a choroid plexus of the fourth ventricleContains a choroid plexus of the fourth ventricle Pyramids – two longitudinal ridges formed by Pyramids – two longitudinal ridges formed by

corticospinal tractscorticospinal tracts Decussation of the pyramids – crossover points Decussation of the pyramids – crossover points

of the corticospinal tractsof the corticospinal tracts

Medulla OblongataMedulla Oblongata

Figure 12.16c

Medulla NucleiMedulla Nuclei

Inferior olivary nuclei – gray matter that relays Inferior olivary nuclei – gray matter that relays sensory informationsensory information

Cranial nerves X, XI, and XII are associated Cranial nerves X, XI, and XII are associated with the medullawith the medulla

Vestibular nuclear complex – synapses that Vestibular nuclear complex – synapses that mediate and maintain equilibriummediate and maintain equilibrium

Ascending sensory tract nuclei, including Ascending sensory tract nuclei, including nucleus cuneatus and nucleus gracilisnucleus cuneatus and nucleus gracilis

Medulla NucleiMedulla Nuclei

Cardiovascular control center – adjusts force Cardiovascular control center – adjusts force and rate of heart contractionand rate of heart contraction

Respiratory centers – control rate and depth of Respiratory centers – control rate and depth of breathingbreathing

Additional centers – regulate vomiting, Additional centers – regulate vomiting, hiccuping, swallowing, coughing, and hiccuping, swallowing, coughing, and sneezingsneezing

The CerebellumThe Cerebellum

Located dorsal to the pons and medullaLocated dorsal to the pons and medulla Protrudes under the occipital lobes of the Protrudes under the occipital lobes of the

cerebrumcerebrum Makes up 11% of the brain’s massMakes up 11% of the brain’s mass Provides precise timing and appropriate Provides precise timing and appropriate

patterns of skeletal muscle contractionpatterns of skeletal muscle contraction Cerebellar activity occurs subconsciouslyCerebellar activity occurs subconsciously

Anatomy of the CerebellumAnatomy of the Cerebellum

Two bilaterally symmetrical hemispheres Two bilaterally symmetrical hemispheres connected medially by the vermisconnected medially by the vermis

Folia – transversely oriented gyriFolia – transversely oriented gyri Each hemisphere has three lobes – anterior, Each hemisphere has three lobes – anterior,

posterior, and flocculonodularposterior, and flocculonodular Neural arrangement – gray matter cortex, Neural arrangement – gray matter cortex,

internal white matter, scattered nucleiinternal white matter, scattered nuclei Arbor vitae – distinctive treelike pattern of the Arbor vitae – distinctive treelike pattern of the

cerebellar white mattercerebellar white matter

Cerebellar PedunclesCerebellar Peduncles

Three paired fiber tracts that connect the Three paired fiber tracts that connect the cerebellum to the brain stemcerebellum to the brain stem

All fibers in the cerebellum are ipsilateralAll fibers in the cerebellum are ipsilateral Superior peduncles connect the cerebellum to Superior peduncles connect the cerebellum to

the midbrainthe midbrain Middle peduncles connect the pons to the Middle peduncles connect the pons to the

cerebellumcerebellum Inferior peduncles connect the medulla to the Inferior peduncles connect the medulla to the

cerebellumcerebellum

Cerebellar ProcessingCerebellar Processing

Cerebellum receives impulses of the intent to Cerebellum receives impulses of the intent to initiate voluntary muscle contractioninitiate voluntary muscle contraction

Proprioceptors and visual signals “inform” the Proprioceptors and visual signals “inform” the cerebellum of the body’s conditioncerebellum of the body’s condition

Cerebellar cortex calculates the best way to Cerebellar cortex calculates the best way to perform a movementperform a movement

A “blueprint” of coordinated movement is sent A “blueprint” of coordinated movement is sent to the cerebral motor cortexto the cerebral motor cortex

Cerebellar Cognitive FunctionCerebellar Cognitive Function

Plays a role in language and problem solvingPlays a role in language and problem solving Recognizes and predicts sequences of eventsRecognizes and predicts sequences of events