Neuroanatomy Flashcards
what are the 3 major frontal divisions of the brain
primary motor cortex
premotor cortex
prefrontal cortex (LARGEST)
what are the INPUTS of the primary motor cortex
thalamus
basal ganglia
sensory area
premotor area
what are the OUTPUTS of the of the primary motor cortex
motor fibers–> brainstem and spinal cord
what is the PURPOSE of the of the primary motor cortex
execution of movements
what is the result of LESIONS TO the primary motor cortex
CONTRALATERAL changes in tone, power, fine coordination
what are the INPUTS to the premotor cortex
thalamus
basal ganglia
sensory area
what are the OUTPUTS from the premotor cortex
primary motor cortex
what is the FUNCTION of the premotor cortex
STORAGE of MOTOR PROGRAMS
what is the result of LESIONS TO the premotor cortex
CONTRALATERAL weakness
coarse ATAXIA
the prefrontal cortex is a component of what brain system
limbic system
where is broca’s area located in relation to the 3 components of the frontal lobes of the brain
behind and under the prefrontal cortex
under the premotor cortex
under and in front of the primary motor cortex
why is the frontal brain called “frontal”
its located in FRONT of the CENTRAL SULCUS of the brain
why is the frontal brain called “frontal”
its located in FRONT of the CENTRAL SULCUS of the brain
list the components of the frontal lobe from anterior to posterior
forehead–> prefrontal cortex –> premotor cortex–> primary motor cortex–> central sulcus
what are the 3 subdivisions of the PREFRONTAL cortex
dorsolateral region
dorsomedial region (includes the cingulate gyrus)
orbitofrontal region
what is the FUNCTION of the dorsolateral region of the prefrontal cortex
executive cognitive functions
–> develop and execute plans for complex goal directed activities
–> conform behaviour to social contingencies
what are the connections that the the dorsolateral region of the prefrontal cortex makes with the rest of the brain
motor and sensory CONEVRGENCE areas
thalamus
basal ganglia –via the caudate (globus pallidus, caudate, substantia nigra)
what is the result of LESIONS to the dorsolateral region of the prefrontal cortex
executive dysfunction
disinterest/emotional reactivity
inattention to relevant stimuli
what are the two components of the dorsomedial region of the prefrontal cortex
superior frontal gyrus
cingulate gyrus
what is the FUNCTION of the dorsomedial region of the prefrontal cortex
motivation
initiation to activity
what is the FUNCTION of the dorsomedial region of the prefrontal cortex
motivation
initiation to activity
what is the result of the LESION to the dorsomedial region of the prefrontal cortex
apathy
decreased drive and spontaneity of movement
loss of cingulate gyrus input to the supplementary motor cortex “releases” activity
–> diminished awareness
–> at worst, usually if bilateral lesions, then can have akinetic mutism
what CONNECTIONS does the dorsomedial region of the prefrontal cortex make with the rest of the brain
anterior cingulate gyrus–> ventral striatum (caudate, putamen)–> globus pallidus and substantia nigra–> thalamus etc (feeds back)
connections to temporal and parietal cortices, cingulate cortex, thalamus, basal ganglia
what are the two components of the basal ganglia
caudate
putamen
what are the components and waht is the location of the orbitofrontal region of the prefrontal cortex
what is the FUNCTION of the orbitofrontal region of the prefrontal cortex
modulation of emotional input
arousal
suppression of distractions
what is the result of a LESION to the orbitofrontal region of the prefrontal cortex
emotional lability
disinhibition
distractability
“hyperkinesis”
OCD like
what are the connections the orbitofrontal region of the prefrontal cortex makes with the rest of the brain
temporal and parietal cortex
thalamus
basal ganglia
insula
amygdala
which region of the prefrontal cortex connects to motor and sensory convergence areas
dorsolateral regions
which region of the prefrontal cortex connects to the temporal and parietal cortices
dorsomedial and orbitofrontal
which region of the prefrontal cortex connects to the thalamus and basal ganglia
all three of them
which region of the prefrontal cortex connects to the insula and amygdala
orbitofrontal region
what are the 3 “frontal syndromes”
dorsolateral syndrome–> “executive dysfunction”
dorsomedial syndrome (anterior cingulate syndrome)–> “amotivation syndrome”
orbitofrontal lesion–> “disinhibition syndrome”
*in reality is rare to have isolated syndromes
what is “Witzelsucht”
uncontrollable tendency to pun, tell jokes/inappropriate humour
can be seen in frontal syndromes
how do we divide the brain VERTICALLY
cortical vs subcortical division
what are 4 functions of the CORTICAL division of the brain
ability
language
motor
sensory
what are 4 functions of the SUBCORTICAL division of the brain
movement
basic function
emotions
connection to FRONTAL lobes–> relay center
which part of the brain contains GRAY matter
cortical
where is the hippocampus located in the brain
temporal lobe, edge of the cortex
is the hippocampus cortical or subcortical
cortical
is basal ganglia cortical or subcortical
subcortical
is the thalamus cortical or subcortical
subcortical
is the brain stem cortical or subcortical
subcortical
which division of the brain–cortical or subcortical–is responsible for the following function:
language
cortical
which division of the brain–cortical or subcortical–is responsible for the following function:
connection to frontal lobes
subcortical
which division of the brain–cortical or subcortical–is responsible for the following function:
movement
subcortical
which division of the brain–cortical or subcortical–is responsible for the following function:
ability
cortical
which division of the brain–cortical or subcortical–is responsible for the following function:
motor
cortical
which division of the brain–cortical or subcortical–is responsible for the following function:
basic function
subcortical
which division of the brain–cortical or subcortical–is responsible for the following function:
emotions
subcortical
which division of the brain–cortical or subcortical–is responsible for the following function:
sensory
cortical
what makes up the subcortical brain division
white matter prohects and deep gray matter bodies
in what brain division is the anterior cingulate cortex (ACC) located
frontal–> dorsomedial
phineas gage sustained damage to what part of the brain
orbitofrontal cortex
in which hemisphere is brocas area located
left
(in frontal lobe, inferior region)
what do lesions in brocas area result in
EXPRESSIVE aphasia
NON FLUENT
in which hemisphere is wernicke’s area located
left hemisphere
in temporal lobe/parietal lobe
what do lesions in wernicke’s area cause
RECEPTIVE aphasia
FLUENT
where does the auditory cortex lie
in the temporal lobe, just in front of the wernicke’s area
what are the functions of the parietal lobe
sense of touch
body position
where is the primary somatosensory cortex located
in the parietal lobe
what is the function of the primary somatosensory cortex
integrates somesthetic stimuli for recognition and recall of form, texture and weight
what is the function of the posterior-lateral area of the parietal lobe
visual-spatial relationships and proprioception
where is the lesion that causes Gerstmann syndrome
dominant parietal lobe
what is Gerstmann syndrome
a lesion in the dominant parietal lobe causes:
deficits in writing (agraphia)
deficits in calculating (acalculia)
left right disorientation
abnormalities in finger naming
what are the functions of the DOMINANT parietal lobe
calculation
writing
left right orientation
finger recognition
what happens if you have a lesion to the NONdominant parietal lobe
neglect
anosognosia
(a smaller lesion may cause apraxia)
what is apraxia
spatial-manual deficit
lose the ability to do learned motor tasks–> dressing, other well learned activities
a lesion in what area may cause anosognosia
non dominant parietal lobe
a lesion to what area may cause acalculia
dominant parietal lobe
what are some of the functions of the temporal lobes
comprehension
sound
speech
what is the function of the hippocampus
memory
what area is affected in kluver bucy syndrome
anterior temporal lobes
list the symptoms of kluver-bucy syndrome
amnesia
docility
pica
hyperphagia
hyperorality
hypersexuality
visual agnosia
what is the function of the occipital lobe
information related to sight
what brain structures make up the diencephalon
thalamus and hypothalamus
what brain structures make up the brain stem
thalamus and hypothalamus
midbrain
pons
medulla
what brain structures make up the hindbrain
cerebellum
pons
medulla
what brain structures make up the forebrain
cerebral structures (cerebral cortex, white matter, subcortical structures)
thalamus and hypothalamus
what brain structures make up the telencephalon
cerebral structures (cerebral cortex, white matter, subcortical structures)
what brain structures make up the mesencephalon
midbrain
what brain structures make up the metencelphalon
pons
cerebellum
what brain structures make up the myelencephalon
medulla
where is the insula located
between the parietal and temporal lobes basically
what area is responsible for mental flexibility
dorsolateral PFC
(lesions lead to concreteness, inability to set shift, perseveration etc)
is brocas area in the dominant or nondominant hemisphere
DOMINANT hemisphere
where are the cortical association areas located
parietal lobe
what is the function of the cortical association areas
integrates and processes sensory information i.e auditory and visual
what is the function of wernickes area in the DOMINANT hemisphere
communication
what is the function of wernickes area in the NONdominant hemisphere
receptive aprodosia
(receptive prosody of speech)
where does visual and cognitive processing happen
in the occipitotemporal gyri
what is the function of the parahippocampal gyri
learning and memory
what is the function of the insular lobe
located internal to the lateral sulcus
responsible for NOCICEPTION and regulation of AUTONOMIC FUNCTION
what is the result of damage to the anterior cingulate cortex
apathy, amotivation
what makes up the limbic lobe
ACC
subcallosal gyrus
cingulate gyrus
parahippocampal gyrus (includes the entorhinal cortex which links olfactory system, cingulate gyrus, orbital cortex, amygdala, and temporal cortex to the hippocampus)
what are the subcortical structures
the substantia nigra is in what part of the brain
part of midbrain
what structures make up the dorsal striatum
caudate and putamen
where does the dopamine that feeds into the dorsal striatum/ caudate+ putamen originate
substantia nigra pars compacta
what is the function of the caudate
motor function
cognitive function
what are the two parts of the ventral striatum
nucleus accumbens
olfactory tubercle
what part of the brain is a major producer of serotonin
raphe nucleus
where does the dopamine that feeds into the ventral striatum come from
ventral tegmental area
*reward/aversion related cognition
*dopaminergic hyperactivity leads to + symptoms
what brain structure produces dopamine for the nigrostriatal pathway
substantia nigra pars compacta
what is the function of the pons
relays signals from forebrain to cerebellum
deals with sleep, respiration, swallowing, bladder control, hearing, equilibrium, taste, eye movement, facial expression and sensation and posture
what structure in the brain produces norepinephrine
locus ceruleus
where is the locus ceruleus located in the brain
in the pons
what cranial nerves are found in the pons
V
VI
VII
VIII
what is the function of the medulla
control of ventilation via signals from the carotid and aortic bodies
cardiovascular SNS, PNS
vasomotor center
reflex center for vomiting, coughing, swallowing, sneezing
what part of the brain is responsible for:
swallowing
pons
reflex is in medulla
what part of the brain is responsible for:
vomiting reflex
medulla
what part of the brain is responsible for:
bladder control
pons
what part of the brain is responsible for:
control of ventilation
medulla
where is the vasomotor center of the brain
medulla
what are the structures involved in the mesolimbic dopaminergic pathway
ventral tegmental area–> dopamine to ventral striatum (nucleus accumbens and olfactory tubercle)
–> dopamine hyperactivity = + symptoms
–> reward/aversion related cognition
what are the structures involved in the mesocortical dopaminergic pathway
ventral tegmental area–> dopamine release to prefrontal cortex
–> executive function
–>low dopamine transmission = negative symptoms
what are the structures involved in the nigrostriatal dopamine pathway
substantia nigra pars compacta–> dopamine to dorsal striatum (caudate and putamen)
–> motor function
what are the structures involved in the tuberoinfundibular dopaminergic pathway
arcuate nucleus–> dopamine release into median eminence, circulates through hypophyseal portal system, and INHIBITS release of prolactin in pituitary–> prolactin inhibition
what brain system is affected in restless leg syndrome
hypothalamospinal
what brain system is affected in tremor
incertohypothalamic
what tests should be ordered to work up chorea
CBC
TSH
ESR
C3
C4
ANA/ENA
anti-dsDNA
calcium +/- PTH
CT head
serum ceruloplasmin
list autoimmune causes of chorea
APLAS
NMDA-R
PANDAs
Sydenhams
SLE
chorea gravidarum
list congenital causes of chorea
perinatal asphixia
kernicterus
list drug induced causes of chorea
neuroleptics
amphetamines
cocaine
stimulants
adrenergics
l-dopa
direct acting dopamine agonists
phenytoin
OCPs
list endocrine causes of chorea
hyperthyroidism
hypoparathyroidism
list infectious causes of chorea
neurosyphillis
HIV encephalitis
how do you distinguish huntingtons chorea from tardive dyskinesia
huntingtons–> typically both upper and lower face; limbs, gait equally if not more affected; respiratory and diaphragmatic chorea
tardive dyskinesia–> typically lower face, tongue and lips more than extremities; respiratory and diagphragmatic chorea
asterixis is associated with what conditions or meds
hepatic, uremic encephalopathy (toxic-metabolic)
anticonvulsants (esp. valproic acid)
lithium
clozapine
*may also be seen with midbrain, thalamic or frontal disease
