BIO 168 chapter 14: The Brain and Cranial Nerves

NEED TO FIX

Brain Regions: Cerebrum

-Largest region

-conscious thought, memory, intellect

Brain Regions: Cerebrum, Gyri

-ridges/folds

Brain Regions: Cerebrum, Sulci

-depressions

Brain Regions: Cerebrum, Fissures

-deep grooves

Brain Regions: Cerebellum

-second largest region

-adjusts movement based on experience

Brain Regions: Diencephalon, Thalamus

-relays sensory/motor information

Brain Regions: Diencephalon, Hypothalamus

-emotions, hormone production

Brain Regions: Diencephalon, Pituitary Gland

-hormone production

Brain Regions: Brain Stem, Mesencephalon

-processes visual/auditory info

Brain Regions: Brain Stem, Pons

-relays sensory info to cerebellum and thalamus

-subconscious somatic/visceral motor control

Brain Regions: Brain Stem, Medulla Oblongata

-relays sensory info to thalamus

-regulates autonomic function

Brain Embryology

-CNS starts as fluid filled tube

Brain Embryology: Primary Vesicles, Prosencephalon (Forebrain)

-gives rise to Cerebrum/Diencephalon

Brain Embryology: Primary Vesicles, Mesencephalon (Midbrain)

-gives rise to Mesencephalon

Brain Embryology: Primary Vesicles, Rhombencephalon (Hindbrain)

-give rise to cerebellum/pons/medulla

Brain Ventricles

-chambers lined with ependymal cells, filled with CSF

Brain Ventricles: Lateral Ventricles (lv)

-in each cerebral hemisphere

-separate by septum pelucidum

Brain Ventricles: Third Ventricle (3rdv)

-in diencephalon

-connects to lv via interventricular foramen

Brain Ventricles: Fourth Ventricle (4thv)

-connects to 3rdv via mesencephalic aqueduct

Protection and Support for Brain: Cranium

-bone provides protection from shock

Protection and Support for Brain: Meninges

-membranes surround CNS surfaces

Protection and Support for Brain: Meninges, Dura Mater (dm)

-fibrous double layer binds bone and am

-sinus between layers with blood

Protection and Support for Brain: Meninges, Arachnoid Mater (am)

-has trabeculae extend to pm

-subarachnoid space with CSF

Protection and Support for Brain: Meninges, Pia Mater (pm)

-thin layer on brain surface

Protection and Support for Brain: Dural Folds

-supportive folds of dm with sinuses

Protection and Support for Brain: Dural Folds, Falx Cerebri

-separates cerebral hemispheres

Protection and Support for Brain: Dural Folds, Tentorium Cerebelli

-separates cerebellum and cerebrum

Protection and Support for Brain: Dural Folds, Falx Cerebelli

-separates cerebellar. hemispheres

Cerebrospinal Fluid (CSF)

-protects brain and transports nutrients/wastes

Choroid Plexus

-produces CSF in ventricles

-CSF circulates thru ventricles, subarachnoid space, and central canal

Blood Supply

-numerous arteries supply neurons with O2

Blood Brain Barrier

-neural tissue isolated from general circulation

-capillaries have tight junctions

-astrocytes regulate permeability

Blood CSF Barrier

-ependymal cells with tight junctions surround capillaries of choroid plexus

Medulla Oblongata: Gray Matter, Autonomic Nuclei

-cardiovascular center controls heart rate

-respiratory rhythmicity center controls respiratory rate

Medulla Oblongata: White Matter

-links the brain and spinal cord

Pons: Gray Matter, Respiratory Nuclei

-apneustic and pneumotaxic centers modify respiratory rate via medulla

Pons: White Matter

-links to cerebellum

Cerebellum: Gray Matter, Cerebellar Cortex

-coordinates/controls body movement

-maintains balance/equilibrium

Cerebellum: White Matter

-arbor vitae connects with brain stem

Mesencephalon: Gray Matter

-superior colliculi process visual info

-inferior colliculi process auditory info

Mesencephalon: White Matter

-links to primary motor cortex, thalamus, spinal cord

Diencephalon: Thalamus

-filter for incoming info to PSC

-emotional state awareness

Diencephalon: Hypothalamus

-controls emotions, hormone production

-stimulated by sensory info, change in chemical stimuli, change in CSF/IF

Limbic System

-establishes emotional states/drives and associated behaviors

Cerebrum

-responsible for conscious thoughts and intellectual functions

-contain four lobes

Cerebrum: Gray Matter, Primary Motor Cortex (PMC)

-directs voluntary control over skeletal muscle

Cerebrum: Gray Matter, Primary Sensory Cortex (PSC)

-receives info wrt touch, pain, taste, pressure, vibration, temperature

Cerebrum: Gray Matter, Primary Visual Cortex

-receives visual info

Cerebrum: Gray Matter, Primary Auditory Cortex

-receives auditory info

Cerebrum: Gray Matter, Primary Olfactory Cortex

-receives olfactory info

Cerebrum: Gray Matter, Association Cortices

-interprets info

Cerebrum: White Matter

-corpus collosum links hemispheres

Cerebrum: Hemispheric Lateralization

-each hemisphere has specific functions not performed by the other

Cerebrum: Hemispheric Lateralization, Left Hemisphere

-speech/interpretive centers

-language-based/analytical skills

Cerebrum: Hemispheric Lateralization, Right Hemisphere

-face recognition

-emotional context of conversation

Brain Activity: Electroencephalogram (EEG)

-monitor electrical patterns of brain

Brain Activity: Electroencephalogram (EEG), Alpha Waves

-in resting, healthy adult

Brain Activity: Electroencephalogram (EEG), Beta Waves

-during stress/concentration

Brain Activity: Electroencephalogram (EEG), Theta Waves

-in children, sleeping adult

Brain Activity: Electroencephalogram (EEG), Delta Waves

-in infants, indicate disorder in adult

Cranial Nerves

-PNS components connecting directly to the brain

Cranial Nerves: Olfactory (I)

-smell

Cranial Nerves: Optic (II)

-vision

Cranial Nerves: Oculomotor (III)

-eyelid/eyeball movement

Cranial Nerves: Trochlear (IV)

-turns eye downward and laterally

Cranial Nerves: Trigeminal (V)

-chewing, face/mouth touch and pain

Cranial Nerves: Abducens (VI)

-turns eye laterally

Cranial Nerves: Facial (VII)

-facial expressions, taste, saliva and tear secretion

Cranial Nerves: Vestibulocochlear (VIII)

-hearing and equilibrium sensation

Cranial Nerves: Glossopharyngeal (IX)

-taste, senses carotid bp

Cranial Nerves: Vagus (X)

-taste, senses aortic bp, slowing down heart rate, stimulates digestive organs

Cranial Nerves: Accessory (XI)

-swallowing, sternocleidomastoid and trapezius

Cranial Nerves: Hypoglossal (XII)

-tongue movements