neuroanatomy exam 1 Flashcards
what is the body’s most complex organ?
the brain
what is the central nervous system
brain and spinal cord
what is the peripheral nervous system
all nerves outside of CNS
what does the forebrain consist of?
cerebral hemispheres
~cerebral cortex
~subcortical white matter
~basal ganglia
~basal forebrain nuclei
thalamus
hypothalamus
epithalamus
what does the midbrain consist of?
cerebral peduncles
midbrain tectum
midbrain tegmentum
what does the hindbrain consist of?
pons
cerebellum
medulla
what does the brainstem consist of?
midbrain
pons
medulla
anatomical directions above the midbrain
anterior = rostral
posterior = caudal
superior = dorsal
inferior = ventral
anatomical directions below the midbrain
anterior = ventral
posterior = dorsal
superior = rostral
inferior = caudal
what is a neuron made up of?
cell body
dendrites
axon with myelin sheath
pre synaptic terminals
describe the gray matter
areas of CNS that primarily contain neuronal cell bodies and dendrites
in the CNS - nucleus
in the PNS - ganglia
describe the white matter
composed of axons, projections of the neurons
in the CNS called tract, lemniscuis, column, peduncle
brain ridges
gyrus
brain grooves
sulcus
fissure if deep
frontal lobe
reasoning
logic
speech
personality
motor activity
parietal lobe
understanding speech
sensation
occipital lobe
vision
temporal lobe
hearing
balance
limbic lobe
emotions
insular cortex
visceral
autonomic
taste
where is broca’s area located?
inferior frontal gyrus
left hemisphere in right handed person
where is the acoustic area?
superior temporal gyrus
what do afferent axons do?
carry info toward the CNS
what do efferent axons do?
carry info away from the CNS
how many histological areas were described by korbinian brodmann?
52
what does the primary sensory cortex do?
discriminates different intensities and qualities if sensory info
what does the secondary sensory cortex do?
performs more complex analysis of sensation
what does the primary motor cortex do?
provides descending control of motor output
located in precentral gyrus
motor planning areas
organize movements
association cortex
controls behavior
interprets sensation
processes emotions and memories
primary somatosensory cortex
within central sulcus
pain, touch, proprioception, vibration
primary auditory cortex
in lateral fissure on superior temporal gyrus
intensity of sound
primary visual cortex
in calcarine sulcus
light/dark shapes
define agnosia
inability to recognize objects
asterognosis/tactile agnosia
visual agnosia
auditory agnosia
define astereognosis
inability to identify objects by touch
define visual agnosia
inability to visually recognize objects
prosopagnosia - faces
define auditory agnosia
unable to differentiate and recognize sounds
what is the location of the primary motor cortex?
in the precentral gyrus, anterior to central sulcus
what happens if there is a lesion of primary motor cortex?
opposite side paresis and loss of movement
dysarthria - poor articulation, cannot produce sound
define apraxia
knowledge of how to perform skilled movement is lost
ideomotor - unable to perform on command
ideational - unable to perform and describe
constructional - inability to comprehend
motor preservation
uncontrollable repetition of a movement
broca’s aphasia
difficulty expressing oneself using language
functions of dorsolateral prefrontal cortex
self-awareness
deciding a goal
planning how to accomplish goal
executing a plan
monitoring the execution of plan
ventral and medial dorsal prefrontal association cortex
impulse control
personality
reactions to surroundings
emotions
motivation
lesion: lack apathy, emotions, insight
parietotemporal association cortex
problem solving
comprehension of communication
spatial relationships
damage on left causes wernicke’s aphasia
what is wernicke’s aphasia?
lack of understanding language
what does aphasia effect?
spoken language
what does alexia effect?
reading ability
what does agraphia effect?
writing ability
describe Broca’s aphasia
severe cases may not produce any language
writing is affected
aware of disorder
describe wernicke’s aphasia
listening to other people speak is meaningless
easily produce spoken sounds but output is meaningless
alexia, inability to write meaningful words
may be unaware of disorder
characteristics of broca’s aphasia
halting speech
tendency to repeat
disordered syntax
disordered grammar
disordered structure of individual words
comprehension intact
characteristics of wernicke’s aphasia
fluent speech
little spontaneous repetition
syntax adequate
grammar adequate
contrived or inappropriate words
comprehension not intact
damage to broca’s area
may cause monotone speech, lack of nonverbal communication, lack of facial expressions and gestures
damaged to wernicke’s area
difficulty in understanding nonverbal communication
neglect
behave as if one side of the body or space does not exist
body or spatial/environment
what percent have neglect after stroke?
43%
only 17% persists
parts of the diencephalon
thalamus
hypothalamus
epithalamus
location of hypothalamus
inferior and anterior to thalamus
location of epithalamus
posterior to thalamus (pineal gland)
subthalamus
inferior to thalamus (only seen in coronal)
what does the thalamus do?
regulated flow of information
it is a relay station
relay nuclei
convey sensory info except olfactory
in the ventral tier
association nuclei
process emotional and memory
anterior, medial, dorsal tier of lateral
nonspecific nuclei
regulate consciousness, arousal, attention
in reticular, medline, intralaminar nuclei
describe thalamic regions involving relay nuclei
interrupt ascending pathways, compromising contralateral sensation
thalamic pain syndrome
severe contralateral pain that may occur with or without stimuli
bilateral thalamic lesions
consciousness will be affected
what does the hypothalamus do?
regulate homeostasis
endocrine regulation
satiety and hunger
emotions
autonomic nervous system
circadian rhythms
pituitary gland
secretions regulated by the hypothalamus control metabolism, stress response, urine production
oxytocin
milk expulsion in lactating females
ADH
increasing reabsorption of water in kidneys preventing large amounts of urine
fsh and lh
synthesis of estrogen, progesterone, testosterone
gh
growth
prolactin
milk production
acth
adrenal hormones
tsh
thyroid hormones
function of epithalamus
pineal gland
regulate circadian rhythms and melatonin
subthalamus
part of the basal ganglia
regulates movement
what can a lesion in cerebellar circuits cause?
wide based ataxic gait
what does the reticular formation do?
consciousness and autonomic functions
what are the two longitudinal sections that the whole brainstem has?
basilar - anterior
tegmentum - posterior
what section of the brainstem is only in the midbrain?
tectum
describe the basilar section
motor structures
descending axons
describe the tegmentum
sensory
cranial nerve nuclei
medial longitudinal fasciculus - eye and head movem.
describe the tectum
reflexive control of eyes and head
cranial nerves in the forebrain
1 and 2
cranial nerves in the midbrain
3 and 4
cranial nerves in the pons
5, 6, 7, and 8
cranial nerves in the medulla
9, 10, 11, and 12
- olfactory
sensory
smell
- optic
sensory
vision
- oculomotor
motor
eye movements - up, down, medial
- trochlear
motor
eye movements - in, down - superior oblique
- trigeminal
sensory and motor
sensation from face, mouth, cornea
jaw muscles
- abducens
motor
eye movements - lateral
- facial
sensory and motor
muscles of facial expression
taste of anterior tongue
lacrimal and salivary glands
- vestibulocochlear
sensory
hearing
balance
- glossopharyngeal
sensory and motor
sensation and taste from posterior tongue
- vagus
sensory and motor
autonomic function of gut
muscles of vocal cords
swallowing
- spinal accessory
motor
shoulder and neck muscles
- hypoglossal
motor
movements of tongue
describe the cranial nerve nuclei of the brainstem
sensory and motor have separate nuclei
sensory long tracts
dorsal column / medial lemniscus
spinalthalamic tract
motor long tracts
corticospinal
corticobrainstem
corticoreticular
corticopontine
fasciculus gracilis (medial)
axons from lower limb and lower trunk
fasciculus cuneatus (lateral)
axons from upper limb, upper trunk, neck
spinothalamic pathway from the body
dorsal root ganglion
dorsal horn of spinal cord
VPL nucleus of thalamus
spinothalamic pathway from the face
trigeminal ganglion
spinal nucleus of trigeminal nerve
VPM nucleus of thalamus
spinothalamic tract
pain and temperature
dorsal column
touch and proprioception
trigeminal lemniscus
sensation from face
superior cerebellar peduncle
connects midbrain to cerebellum
middle cerebellar peduncle
connects pons to cerebellum
inferior cerebellar peduncle
connects medulla to cerebellum
cerebellar functions
coordination of movement, balance, posture
what is the reticular formation?
complex neural network that includes reticular nuclei, their connections, and ascending and descending reticular pathways
where is the reticular formation located?
in the brainstem tegmentum
rostral reticular activating system
ascending reticular activating system
consist of midbrain and pons
conscious state
when damaged: coma
caudal reticular formation
consist of pons and medulla
motor, reflex, and autonomic functions
three regions of midbrain
basis pedunculi
tegmentum
tectum - only in midbrain
things only in the midbrain
cerebral aqueduct
superior colliculus
periaqueductal gray
oculomotor nerve parasympathetic nucleus
oculomotor nucleus
red nucleus
substantia nigra
oculomotor nerve
superior cerebellar peduncle
what does the inferior colliculi do?
relay auditory information from the cochlear nuclei
what does the superior colliculi do?
receives sensory and motor information
involved in reflexive eye and head movements
what does the reticular activating system do?
activates entire nervous system
what is the midbrain tegmentum?
middle of the midbrain
contains cranial nerves 3 and 4
what is the midbrain basis pedunculi?
formed by cerebral peduncles
substantia nigra is one of them
subdivision of the pons
located between midbrain and medulla
corticopontine
anterior section of pons (basilar): descending
posterior (tegmentum): , RF, MLF, CN 5-8
describe the cranial nerves in the pons
5 - sensory info from face
5 - chewing
6 - lateral movement of eye
7 - facial expression
8 - convey info about sound and head position
things only in pons
vestibular nuclei
motor nucleus of trigeminal
sensory and motor roots of trigeminal nerve
middle cerebellar peduncle
abducens nucleus
cochlear nucleus
vestibular nuclei
facial nucleus
CN VIII
CN VII
CN VI
spinal tract
nucleus of spinal tract
what is located in the medulla?
pyramids
CN 9-12
olives
nucleus ambiguus
hypoglossal nucleus
inferior olivary nucleus
raphe nuclei
dorsal motor nucleus of vagus
inferior cerebellar peduncle
what does the medulla do?
contributes to control head movements
coordinates swallowing
helps regulate cardiovascular, respiratory, visceral activity
what connects cerebellum and medulla?
inferior cerebellar peduncle
