chapter 13

4 major brain regions

Cerebrum, diencehalon, brain stem, cerebellum

Gyri

Ridges

Sulci

Depression between ridges

Neuulation

Formation of nervous tissue, begins in 3rd week of embryonic development

Neural plate

Part of the embryoectoderm layer

Notochord

Beneath neural late. It induces the neural plate o form the neural tube, which develops in to the CNS

Neurulation event

Plate develops neural groove, neural groove deepens as folds rise and approach one another, neural crest cells separate from neural folds and form other structures, y the end of 3rd week folds meet and form real ube surrounding the neural canal

Neural crest cells

Tips of the neural folds

Neuropores

Openings of the neural tube. Cranial neuropore and caudal

Spina bífida

Failure to close caudal portion of neural tube

Anencephaly

Substantial or complete absence of a brain. infant dies

Primary brain vesicles

Form by late 4th week from cranial neural tube. Forebrain, midbrain, hindbrain

Prosencehalon

Forebrain

Mesencephalon

Midbrain

Rhombenvephalon

Hindbrain

Secondary brain vesicles

Form by 5th week. Telencephalon, diencephalon, mesecephalon, metencephalon, myelencephalon

Telencephalon

Becomes cerebrum

Diencephalon

Ecomes thalamus, hypothalamus epithalamus

Mesencephalon

Becomes midbrain

Metencephalon

Becomes pons ad cerebellum

Myelencephalon

Becomes mededulla oblongata

Gray matter

Made of neurocell bodies, dendrites and unmyelinated axons

Cortex

Superficial layer of gray matter

Nucleus (center)

Region of gray meter ( cluster of cell bodies) either lose to the surface or deep with the brain

White matter

Consists of myelinate axons and organized in uncles called tracts.

Peduncles

Tracts connecting two regions of the brain

Funiculi

Subdivision of tracts within spinal cord

Ganglia

A bunch a neuron cell bodies

Nerves

Bundles of axons

Nerve plexus

Network of of nerves

Brain protection

Bones of the skull, cranial meninges, cerebrospinal fluid, blood brain barrier

Cranial meninges

Has 3 connective tissue layers, separates and support soft tissue of brain, encloses and protect blood vessels supplying the rain help contain and circulate cerebrospinal fluid.

Pia matter

Innermost meninges; adhere to brain surfac thin ayer of areolar tissue

Arachnoid mater

Lies external to pia matter has arachnoid trabecuale and subarachnoid space made of web collagen and elastic fibers. Lied deep to dura mater

Dura mater

Pugh outer membrane. Made of dense irregular connective tissue in 2 layers : meningeal layer, periosteal layer

Memingeal layer

Deeper layer of dura

Periosteal layer

More superficial layer of ura that forms he periosteum on internal surfaces of cranial bones

Epidural space

Is potential space between dura and the skull. Contains arteries and veins

Dural venous sinuses

Areas in which eningeal layer and periosteal layer separate drain blood from the brain

Meningitis

Inflammation of the meninges, typically by viral infection. Ay result in brain damage or death if left untreated

Encephalitis

Inflammation of the brain

Epidural hematoma

Pool of blood in the epidural space of the brain

Subdural space

Potential space between dura mater and arachnoid mater

Subdural hematoma

Hermorrhage in subdural space. Compression of brain tissue occurs more slowly than epidural hematoma

Cranial dural septa

Sheets of dura mater hat extends into cranial cavity. Forms partitions between brain areas; provide support

Flax cerebri

Largest dural septa, located on midline, separates left nd right hemispheres of the cerebrum.conatins superior sagitario sinus and inferior agita al sinus

Tentorium cerebelli

Separates occipital and temporal lobes from cerebellum. Contains transverse sinuses withi posterior border, straight sinus along midsaggital plane. Has tenorial notch allowing room for brain stem

Falx cerebelli

Separates left and right sides of cerebellar emispheres ins along sagitario plane. Contains occipital sinus

Diaphragma sellae

Smallest of dural septa. Forms roof over sellica of sphenoid bone and pituitary gland

Dural venous sinuses

Modified vein that are rage, blood filled spaces that collect blood draining from brain. Usually triangular in section

Confluence of sinuses

Superior and inferior agitar sinuses, transverse sinuses straight sinus converge here

Ventricles

Cavities within the brain, lined ependymal cells, contain cerebrospinal fluid, connect with each other and with spinal cord central canal

Cerebrospinal fluid

Clear, colorless liquid surrounding CNS. Inculcates in vesicles and subarachnoid space. (Buoyancy) Reduces brains apparent weight by 95%, provides a liquid cushion (protection), transport of nutrients/ wastes and protects against fluctuations (environmentally stability)

Cerebrospinal fluid

Formed by choroid plexus in each ventricle. Blood plasma filtered from blood capillaries across both capillary walls and the pia mater its composition is modified by the ependymalell as it moves through these cells. Fluid is then released into ventricle and is referred to as CSF

Blood Brain barrier

Egulates which substances enter brain interstitial fluid, helps prevents neuron exposure to harmful substances(drugs wastes), composed of specialized capillaries reduced in certain locations for functional reasons (Ike choroid plexus needs to produce CSF)

Waste removal

Te-laden CSF drains into dural venous sinuses. Meningeal lymphatic vessels and glymphatic system

Meningeal lymphatic vessel

Located within meninges, absorb and transport excess fluid

Glyphatic system

Perivascular feet of atrocytes facilitate removal of waste

Cerebrum

Origin of all complex intellectual functions, two large cerebral hemispheres (each divided into lobes). Center of intelligence and reasoning, thought Emory, judgement, voluntary control of skeletal muscle, conscious perception of senses

Frontal lobe

Anterior part of cerebrum. Contains precentral gyrus, central sulcus, lateral sulcus. Functions: motor control, concentration, verbal communication, decision making, planning persionality.

Parietal lobe

Evaluating shape and texture

Temporal lobe

Hearing and smell

Occipital lobe

Visions and visual memories

Ínsula

Small lobe that can be observed by pulling away temporal lobe. Memory and sense of taste

Motor areas

Housed within frontal lobes. Primary motor cortex, motor speech area, frontal eye field, premotor cortex

Primary motor cortex

Located in presentar gyrus. Controls skeletal uscle activity

Aracnoid trabeculae

Extend to pia mater though subarachnoid space

Subarachnoid space

Contains cerebral fluid

Motor areas

Housed within frontal lobes. Mary motor cortex, motor speech area , rental eye field, pre motor cortex

Primary motor cortex

Located in precentral gyrus. Ontrol skeletal muscle activity on opposite side of body.

Motor speech area

Located in infrerolateral portion of frontal lobe. Controls movement for vocalization

Frontal eye field

Located on superior urface of middle frontal gyrus regulates eye movements needed for reading and binocular vision

Promotor cortex

Located anterior to precentral gyrus. Coordinates learned skilled activities

Primary somatosensory cortex

Located in post central gyrus of parietal lobes. Receives somatic information from proprioceptors, touch,pressure pain, temporal captors. Large regions for lips, fingers, genital regions

Somatosensory association area

Immediately posterior to postcentral gyrus. Integrates touch info allowing us to identify objects by feel

Primary visual cortex

Located within occipita lobe; receives processes, stores visual information

Secondary association area

Surrounds primary visual cortex. Integrates and interprets color, form, to allow identification recognition of things (like faces)

Primary auditory cortex

Located within temporal lobe. Receives processs stores auditory information

Auditory association area

Located temporal lobe; integrates and interprets sounds

Primary olafactory cortex

Located within temporal lobe. Receives processes and stores odor information

Primary gustatory cortex

Located within ínsula receives processes stores taste info

Functional brain regions

Integrate information from multiple association area

Prefrontal cortex

Located rostral to premotor cortex. Complex thought, judgement, personality, planning, deciding

Wernicke area

Typically located in left hemisphere, overlaps parietal and temporal beds. Involved n language comprehension

Central white matter

Lies deep to gray cerebral cortex. Composed of myelinated axons grouped into tracts.

Association tracts

Connects regions of cerebral cortex within same hemisphere. Arcuate fibers and longitudinal fasciculi

Arcuate fibers

Short tract connecting neighboring gyri

Longitudinal fasciculi

Longer tracts connecting gyri in different lobes

Commissural tracts

Connects region in different hemispheres

Projection tracts

Link cerebral cortex to inferior brain regions and spinal cord

Petalias

Protrusion of a lobe on one side compared to other side. Right handed individuals end to have right frontal petalis and left occipital petalis.

Cerebral lateralization

Two sides of cerebrum exhibit differences in higher order functions. (Certain functions are more dominant in one hemisphere than the other)

Categorical hemisphere

Is usually left hemisphere . Pecialized for language abilities, functions in categorization and analysis.contains wernicke and motor speech area

Representational hemisphere

Usually the right hemisphere. Concerned with visuospatial relationships, imagination, comparison of senses

Epilepsy

Neurological disorder. Neurons transmitting action potential too frequently and rapidly

Cerebrovascular

Reduced blood supply to part of brain due to blocked arterial blood vessel or hemohage

Cerebral nuclei

Paired masses of gray matter located deep within central white matter. Helps regulate motor output

Caudate nucleus

Enlarged head nd slender tail paralleling lateral ventricl

Lentiform nucleus

Rounded mass between ínsula and diencephalon. Composed of putame and globus

Putamen

Helps control movements at subconscious level.