Brain Structures

Exam 3

neurulation

formation of the neural tube

cephalization

development of the anterior part of the CNS as a center or neural control (mouth and sense organs)

anterior end

this part of the neural tube becomes the brain

posterior end

this part of the neural tube becomes the spinal cord

first step in neurulation

ectoderm thickens to become the neural plate

second step in neurulation

neural plate invaginates, forming a groove with raised edges on either side called neural folds

third step in neurulation

the neural folds fuse, forming the neural tube

neurocel

central cavity of the neural tube

fourth step in neurulation

neural tube differentiates into the primary brain vesicles of the CNS

secondary brain vesicles

these arise from primary brain vesicles during embryologic development

neural crest

part of the neural ectoderm that is pinched off and moves to a position just lateral to neural tube, forming somites

somites

bulges on either side of the neural tissue that give rise to dermis, muscles, and skeleton

ectoderm

primary germ layer nervous tissue originates from

primary brain vesicles

prosencephalon, mesencephalon, and rhombencephalon

prosencephalon

forms the forebrain in an adult

mesencephalon

forms the midbrain in an adult

rhombencephalon

forms the hindbrain in an adult

telencephalon and diencephalon

secondary brain vesicles formed from the proencephalon

metencephalon and myelencephalon

secondary brain vesicles that form from the rhombencephalon

anencephaly

neural tube defect resulting from failure to close of the anterior neural tube, complete or partial absence of skull or brain

spina bifida

neural tube defect resulting from failure to close of posterior neural tube, resulting in meninges or spinal cord protrusion. can cause paralysis, reduced ambulation, or incontinence

folic acid

intake of this nutrient prevents neural tube defects

midbrain and cervical flexures

result from packing more brain into a small space

temporal lobes

these protrude and enclose the dienecephalon due to rapid cerebrum development in a closed space

sulci and gyri

increase surface area for neurons in the enclosed space of the skull

gray matter

unmyelinated nerve fibers that comprise the cerebral cortex and most nervous system cell bodies

white matter

myelinated and unmyelinated nerve fibers that comprises inner region of cerebrum with more volume

regions of adult brain

cerebrum, diencephalon, brain stem, and cerebellum

lateral ventricles

2 c shaped chambers with horns that circulates CSF

third ventricle

ventricle located in the diencephalon that connects to the 4th ventricle via the cerebral aqueduct

fourth ventricle

ventricle located in the hindbrain, dorsal to the pons and medulla

septum pellucidum

thin transparent membrane that separates anterior horns of the lateral ventricles

interventricular foramen

located between lateral ventricles and third ventricles to connect them

cerebral aqueduct

connected the third and fourth ventricles like a narrow canal

laterla apertures

located on the side walls of the fourth ventricles so it can flow into subarachnoid space

median longitudinal fissure

separates the cerebral hemispheres from each other

transverse cerebral fissure

separates cerebral hemispheres from the cerebellum

central sulcus

separates the frontal and parietal lobes

parieto-occpital sulcus

separates the parietal and occipital lobes

lateral sulcus

separates the temporal lobe from the frontal and parietal lobes

frontal lobe

cerebral lobe in the front

parietal lobe

cerebral lobe on the top/side

occipital lobe

cerebral lobe in the back

temporal lobe

cerebral lobe the sides

insula

cerebral lobe on the interior

primary motor cortex

allows for conscious control of precise/skilled voluntary movements in face, tongue, and hands. FRONTAL LOBE

premotor cortex

helps to plan movements by selecting basic motor tasks. FRONTAL LOBE

broca’s area

motor speech area that directs muscles of speech production and plans speech. FRONTAL LOBE

wernicke’s area

recognizes speech patterns and inputs into a coherent whole, processes language in general. TEMPORAL LOBE

frontal eye field

controls voluntary eye movements. FRONTAL LOBE

primary auditory cortex

interprets gross parts of sound like pitch, volume, location. TEMPORAL LOBE

auditory association area

perceives the sound stimulus and compares to stored memories. TEMPORAL LOBE

prefrontal cortex

controls complex behaviors like decision making, personality, intellect, and abstract ideas. FRONTAL LOBE

posterior association area

recognizes patterns and faces, localizing us in space and binds sensory input into a coherent whole. TEMPORAL, PARIETAL, AND OCCIPITAL LOBES

primary somatosensory cortex

receives info from sensory receptor and identifies region being stimulated. PARIETAL LOBE

somatosensory association area

integrates sensory inputs to understand an object’s texture, size, and past memories of it. PARIETAL LOBE

primary visual cortex

receives visual info coming from the retina. OCCPITAL LOBE

visual association area

uses past visual experiences to interpret visual stimuli. OCCPITAL LOBE

olfactory cortex

conscious awareness of odors. TEMPORAL LOBE

vestibular cortex

perceives the position of the head in space and gives us a sense of balance. INSULA

gustatory complex

perceives taste stimuli. INSULA

visceral sensory area

conscious perception of visceral sensations. INSULA

affective language area

nonverbal components of language like emotional tone. RIGHT HEMISPHERE

hemispheric lateralization

each hemisphere has its own unique abilities not done by the other

cerebral dominance

the hemisphere dominant for language

left hemisphere

dominant hemisphere for most - involved in language, math, and logic

right hemisphere

non-dominant hemisphere for most - involved in visuo-spaital skills, intuition, emotion, and art skills