Neuroanatomy Flashcards
Ramon y Cajal
investigated that neurons are not physically connected, won the Nobel Prize
Meninges
protective sheaths around the brain
Sulci
grooves/spaces
Gyri
neural folds of tissue
Coronal plane
divides dorsal/ventral (belly/back)
Horizontal plane
Dividing rostral/caudal (top and bottom)
Rostral
toward the beak (front)
Caudal
toward the tail (back)
sagittal
dividing left-right
ventral
front
dorsal
back
dura mater
outer layer of meninges, hard,
arachnoid mater
middle layer of meninges, soft, spongy, web-like
pia mater
smaller surface blood vessels of brain and spinal cord
subarachnoid space
between pia and arachnoid, full of CSF
cerebrospinal fluid (CSF)
bathes and floats brain in skull
frontal lobe
(in the front) executive function, motor function, problem solving, memory, language, initiation, judgment, impulse control
parietal lobe
caudal to frontal lobe, dorsal to temporal lobe
- processing sensory information, interpreting visual information, processing language, mathematics, orientation of body to space
temporal lobe
ventral to frontal and parietal lobes
- auditory processing and perception, structural memory, visual processing
- comprehension of speech, integration of patterns of stimuli
occipital lobe
back of the brain, caudal to parietal and temporal lobes
-visual processing
lateral (Sylvian fissure)
separates temporal from parietal lobe)
central (Rolandic fissure)
separates parietal lobe from frontal lobe
falx cerebri
made of dura mater, divides cerebral hemisphere, provides cushion and cradles cerebrum
cerebellum
“little brain” covered by cerebellar cortex
important to motor system, coordination, balance, speech, posture
brain stem
stem of the brain from the medulla to the diencephalon, excluding cerebellum
medulla
caudal portion of brain stem, lower border rostral to spinal cord, contains reticular formation
-regulation of cardiovascular system, respiration, skeletal muscles
pons
large bulge in brain stem, ventral to cerebellum, rostral to medulla, caudal to midbrain
-sleep, arousal, relays info from cortex to cerebellum
midbrain
(mesencephalon) surrounds cerebral aqueduct, central of three divisions of brain (tectum and tegmentum)
- vision, hearing, sleep/awake, arousal, temperature, regulation
ventricles
hollow interconnected chambers in brain filled with CSF
lateral ventricles
largest chambers in forebrain, connected to third ventricle
first and second ventricles run right and left laterally
third ventricle
located in middle of brain, walls divide surrounding part of brain into symmetrical halves
cerebral aqueduct
connects third ventricle and fourth ventricles of brain
fourth ventricle
located bewteen cerebellum and pons, brings CSF to subarachnoid space
choroid plexus
special tissue with rich blood supply, manufactures, CSF
white matter
axon bundles sending info from subcortical structures up to cortical areas, large concentration of myelin gives white appearance in deep parts of brain, spinal cord, cerebellum
gray matter
contains cell bodies of neurons, present in brain, brain stem, cerebellum and spinal cord. includes regions involved in sensory perception, memory, emotions, muscle control, decision-making, self-control
glia
inside protection line outer membrane of blood brain barrier, form layer around brain blood vessels, important for transport of ions from brain to blood, surround neuron
three types: oligodendrocytes, astrcytes, microglia
oligodendrocytes
provides support to axond and produce myelin sheath
astrocytes
forms matrix to keep neurons in place and isolate synapse perform phagocytosis (push against neural debris, to engulf and digest it)
microglia
smallest glial cells, key components of brain immune system, mediate neuro-inflammatory process, subtle brain immune response in acute reactions to injury in absence of blood-brain barrier
insular cortex
in each hemisphere, folded deep within lateral sulcus
-consciousness, emotion, regulation of homeostasis, perception, motor control, self-awareness, interpersonal experience
thalamus
two lobes (inner chamber) connected by gray matter, contains nuclei that project and receive info to/from cerebral cortex
- sensory information, arousal, memory, cognitive functions
- way station - preliminary organization of sensory and some motor info
hypothalamus
under thalamus, controls ANS and endocrine system
fight, feed, flee, mate, hormones, thirst, hunger, sex
pituitary gland
below hypothalamus, attached via nerve fibers, produce hormones that control bodily functions
anterior pituitary gland
secretions controlled by hypothalamic hormones, body’s master gland
sex hormone release
posterior pituitary gland
extension produced by hypothalamus, contains hormone secreting terminal buttons of axons, cell-bodies in hypothalamus
-milk ejection, uterine contractions, urine output
basal ganglia
collection of subcortical nuclei in telencephalon, lie beneath anterior portion of lateral ventricles,
-voluntary movement, procedural learning, routine behavior, eye movement, cognition, emotion
caudate
part of dorsal striatum, motor processes, procedural learning, associative learning, executive functions
putamen
part of dorsal striatum, regulate movements, influence types of learning, role in degenerative neuro disorders
globus pallidus internal
internal segment, received motor-related cortical signals through striatum, external GP, and subthalamic nucleus
globus pallidus external
external segment, inhibit tonic inhibitory output neurons
glial cells
offer structural support to hold everything in place
orbital frontal lobes
executive function, initiation, planning
claustrum
subcortical
consciousness, unify awareness (temporal lobe)
projection fibers
afferent - sensory - go up from lower parts to cortex (ad)
efferent - motor - go from cortex to lower (ex)
association fibers
connect areas within same hemishphere
unilateral
commissural fibers
travel across commissures in brain, send from one hemisphere to the other
corpus callosum
hemispheres commiserate by communication
corpus callosum runs right across middle information, chopped for sagittal slice
internal capsule
contains fibers going to/from cerebral cortex - projection fibers
carries info past basal ganglia, separates caudate nucleus and thalamus from putamen and globus pallidus
cingulate cortex
The cingulate cortex, a part of the limbic cortex, is a part of the brain situated in the medial aspect of the cerebral cortex. The cingulate cortex includes the entire cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the cingulate sulcus.
emotional processing area of brain
back area for processing affective components (ouch)
pain pathway cingulate cortex
contralateral, goes up to thalamus to cingulate cortex, travels to sensory homunculus
hippocampus
emotion, memory, ANS, declarative memory
shaped like a seahorse
amygdala
almond shaped
emotion survival instincts, memory, fear, process affect
homunculi
neurological map of anatomical divisions of body
motor and sensory
corpus callosum bridging the two
longitudinal fissure is in the middle
motor homunculus
descending ventral left side
leave frontal motor area and descend spinal cord when synapses on alpha neurons project ventrally out and form mixed nerve, ending on muscles and other peripheral nerves
sensory homunculus
ascending, dorsal, right side
information comes up spinal cord and synapses at level of medulla, crosses over near top and ascends through myelinated white fibers, goes through thalamaus and comes up through capsule, projects through cortical tissue to cortex
primary motor cortex
precentra gyrus
motor representation arranged in orderly manner
representations lie along central sulus
primary sensory cortex
postcentral gyrus, handles signals coming from thalamus, transmit from gyri to brain stem/spinal cord
spinal cord
ventral/front/motor
dorsal/back/sensory
spinocortical pathway
afferent
sensory pathway starts in spinal cord and ascends to cortex
PNS –> dorsal root ganglion –> up spinal cord ipsilateral –> synapses over at medulla –> thalamus releases NT
spinothalamic pathway
pain/temperature
crosses over immediately on entering spinal cord, travel upwards to thalamus
sent to cingulate cortex and sensory cortex in parietal lobe
Brown-Sequard syndrome
lesion of half the spinal cord results in a distinctive pattern of sensory loss, such that person loses sense of pain on opposite side of body below the lesions, and sense of touch on same side as and below the lesion
ventral root ganglia
carries neural signals away from CNS to limbs/organs
dorsal root ganglia
carries neural signals from limbs/organs to CNS
corticospinal
efferent, starts in cortex
project from cortical and go down to loops through basal ganglia and then thalamus and then cerebelluma and finally spinal cord
decussated at lower medulla and gows down contralaterally
nerves synpase on alpha neuron that project ventrally out of spinal cord and form mixed nerves
CNS
brain and spinal cord
PNS
somatic and autonomic nervous systems
somatic nervous ssystem
voluntary
sensory (afferent)
motor (efferent)
autonomic nervous system
involuntary
parasympathetic and sympathetic
regulates unconscious activities
maintaining homeostasis
parasympathetic NS
controls organs when body is at rest
sympathetic NS
controls organs in times of stress
Enteric NS
embedded in lining of GI tract
regulates GI functions
receives input from ANS
cranial nerves
12 cranial nerves on ventral surface of brain
bring info from sense organs to brain, control muscles, connected to glands or internal organs
(On Old Olympus Towering Top A Finn And German Viewed Some Hops)
peripheral nerves that go directly to the brain
sections of spinal cord
cervical thoracic lumbar sacral coccygeal
carotid arteries
bring blood to the brain
anterior cerebral artery
goes back to parietal area (HAL)
middle cerebral artery
lateral side of cortex, covers cortical tissues and interal organs
posterior cerebral artery
middle of the brain
circle of Willis
provides collateral blood supply if needed
