• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/99

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

99 Cards in this Set

  • Front
  • Back
  • 3rd side (hint)
What does the frontal cortex control?
initiation and control of voluntary movement, language expression; attention; emotion
What does the parietal cortex control?
perception and discrimination of somatosensory stimuli; integration of somatosensory stimuli with visual and auditory info
What does the occipital cortex control?
perception and recognition of visual stimuli
What does the temporal cortex control?
perception and discrimination of auditory stimuli; language perception; vision; learning and memory formation
What does the insular cortex control?
visceral sensations such as baro and GI receptors
What does the internal capsule convey?
UMN afferents and efferents from cortex down to lower levels and other regions of the cortex, lesions here cause wide ranging effects
What does the corpus callosum convey?
largest pathway in the brain which interconnects homotopic areas in contralateral hemisheres
What does the anterior commissure of the corpus callosum connect?
interconnects area of the middle and inferior temporal gyri: temporal lobes and olfactory bulbs
What are association bundles of the cerebral cortex?
intracortical fasciculi interconnecting different regions of the same hemisphere, arise from pyramidal neurons in layer II of the cortex
What does the cingulum association bundle connect and where is it located?
interconnects parietal and occipital lobes with the frontal lobe; located deep to the cingulate gyrus on the medial surface of the hemisphere
What does the superior longitudinal fasciculus (arcuate fasciculus) association bundle connect and where is it located?
interconnects temporal and frontal lobe language areas; damage in the dominant hemisphere results in conduction aphasia
What are the six layers of the neocortex?
Supragranular layers: I (molecular); II (external granular); III (external pyramidal)
Internal granular layer (IV)
Infragranular layers: V (ganglionic or internal pyramidal layer); VI (fusiform layer)
None
What are the two basic cell types of the cerebral cortex?
pyramidal cells - long axon projection neurons in layers II, III, V, VI; Stellate or granule cells - short axon "local circuit" neurons in layer IV
What fibers are received in the internal granule layer (IV) of the cortex?
thalamocortical fibers, especially from ventral tier thalamic nuclei and geniculate nuclei
What fibers project from the ganglionic or internal pyramidal layer (V) of the cortex?
corticostriate, corticospinal, corticopontine, corticobulbar, corticorubral fibers
What fibers project from the fusiform layer (VI) of the cortex?
corticothalamic fibers
What fibers are formed from the supragranular layers (II, III) of the cortex?
intracortical (associational) and intercortical (callosal) connections to other parts of the cortex within the ipsilateral or contrallateral cortex
What are the characteristics of the pyramidal cells of the cerebral cortex?
located within layers II, III, V, and VI; include giant Betz cells which give rise to some corticospinal tract; have an apical dendrite projecting toward cortical surface, basal dendrites project horizontally and an axon which extends into subcortical white matter
What are the characteristics of the stellate or granule cells of the cerebral cortex?
prominent in layer IV; have short axon that does not leave the cortex (intracortical)
What Brodmann's areas are associated with motor control cortex?
4, 6
What Brodmann's areas are associated with somatosensory cortex?
3,1, 2
What Brodmann's areas are associated with visual input?
17, 18, 19
What Brodmann's areas are associated with auditory input?
41, 42
What are mirror neurons and there function?
neurons of the frontal cortex which fire both when you move and when you observe another person make the same type of movement; also the the same neurons which fire when you smell something noxious or observe another smelling something noxious
What are the "big six" functional areas of the cerebral cortex?
S1, M1, V1, A1, Broca, Wernicke
What are the characteristics of the primary somatosensory cortex (S1)?
in postcentral gyrus (BA 3,1,2); has dense lamina IV, receives afferents from the VPL and VPM thalamic nuclei which come from medial lemniscal, spinothalamic, and trigeminothalamic tracts; somatotopy with lower limb hanging medially for each cortical area
What are the symptoms of a lesion of the primary somatosensory cortex (S1)?
contralateral deficits, inability to discriminate size, texture, and shape, loss of limb position sense, loss of pain localization
What are the characteristics of the primary motor cortex (M1)?
in precentral gyrus (BA 4, 6); large lamina V with giant Betz cells and very small lamina IV, receives afferents from ventral lateral thalamic nucleus relay from cerebellar afferents; efferents include corticospinal, corticobulbar, corticopontine, corticostriate, corticothalamic; is the location of UMNs; somatotopy
What are the symptoms of a lesion of the primary motor cortex (M1)?
spastic paralysis of the contralateral face, arm, and leg
What are the characteristics of the primary visual cortex (V1)?
located along the banks of calcarine sulcus (BA 17); prominent lamina IV; afferents from the lateral geniculate of thalamus with visual input from the contralateral visual hemifield of each eye; posterior 1/3 has afferents from the macular retina; efferents project to superior colliculus of tectum and generate visual tracking eye movements
What are the symptoms of a lesion of the primary visual cortex (V1)?
cortical blindness - inability to see anything consciously; loss of reflex closure of eyelids to bright light if bilateral lesion; unilateral lesions cause contralateral homonymous hemianopsia (contralateral visual field loss of each eye)
What are the characteristics of the primary auditory cortex (A1, A2)?
located in the superior temporal gyrus in transverse temporal gyri (BA 41, 42); large lamina IV; afferents from the medial geniculate nucleus of thalamus relaying bilateral auditory inputs; tonotopic localization with high frequencies medially and low frequencies laterally
What are the symptoms of a lesion of the primary auditory cortex (A1, A2)?
Area 41: unilateral lesion may not result in noticable hearing deficits bc compensation with other ear; Area 42: inability to recognize or discriminate sounds
What are the characteristics of Broca's area and what symptoms does a lesion here produce?
usually Left inferior frontal gyrus (BA 44,45); related to speech production; lesion causes expressive aphasia- in which the production of speech is impaired - telegraphic speech, able to comprehend just not express
What are the characteristics of Wernicke's area and what symptoms does a lesion here produce?
usually left superior temporal gyrus encircling the primary auditory cortex; invovled in language comprehension, lesion causes Wernicke's aphasia where understanding speech is lost leading to nonsense speech
What are the characteristics of the secondary somatosensory cortex (S2)?
caudal to S1 buried in upper bank of lateral fissure (BA 40); contains a separate, less detailed somatotopic map from S1, afferents from S1, VPL, VPM and posterior and intralaminar nuclei; responds to painful stimuli
What are the symptoms of a VPL/VPM lesion?
complete numbness on entire contralateral side of body with deficits in postion sense, and discrimination of texture, size, and shape (astereognosis)
What are the characteristics of the posterior parietal cortex?
located in superior parietal lobule (BA 5,7); afferents from primary and secondary somatosensory, visual, and auditory cortex; integrates various senses and involved in visual attention
What are the symptoms of a lesion of the posterior parietal cortex?
astereognosis - unable to recognize objects by touch though sensory pathways are intact; also neglect syndrome- denial/neglect of contralateral body
What are the characteristics of the Premotor Cortex (PM)?
anterior to primary motor cortex (BA 6); involved in preparation of movement; afferents from ventral anterior nucleus of thalamus relay from basal ganglia and corticocortical afferents from other motor and somatosensory cortices; efferents: corticospinal, corticobulbar, corticopontine, corticostriate, corticothalamic
What are the characteristics of the Supplementary Motor Cortex (SMA)?
BA 6, involved in coordinating posture and complex bilateral movements; afferents from basal ganglia
What are the characteristics of the Frontal Eye Field (FEF)?
in medial BA 6 rostral to premotor cortex, generates saccadic eye movements; stimulates eye and head movements to contralateral side; affferents from medial dorsal thalamic nucleus and dorsolateral prefrontal cortex; efferents to corticotectal tract and corticobulbar to PPRF
What are the symptoms of a lesion to the dorsolateral prefrontal cortex lesion?
normally can inhibit superior colliculus output of reflex eye and head movement towards stimuli (look away task); lesion leads to increaed antisaccade errors - inability to disregard or not look at a stimuli
What is language?
communication by means of symbols, including non-verbal
What is phonation?
forcing air past the closing vocal cords, function of CN X, larynx and respiratory system
What is articulation?
uttering, pronouncing distinct sounds, function of muscles of lips, tongue, palate, and pharynx (CN VII, IX, X, XII), cerebellum and extrapyramidal systems
What is aphasia?
disorder of previously acquired language ability caused by lesion in one or more critical cortical areas in the dominant hemisphere
What artery supplies the cortical language areas?
middle cerebral artery
If an aphasic person is able to speak well but their communication is impaired, where is the lesion?
Wernicke's of posterior superior temporal lobe
If an aphasic person is unable to speak but is able to demonstrate normal comprehension, where is the lesion?
Broca's of posterior inferior frontal lobe
What is fluency?
the ease, facility, and quantity of speech regardless of content or meaning
Where is the lesion and what are the symptoms of a conduction aphasia?
lesion of the arcuate fasciculus connecting Broca's and Weirnicke's areas; pt is fairly fluent, some paraphasic errors, some limited comprehension and repetition errors
What is common among any/all Perisylvian aphasia (broca's, wernicke's, or conduction)?
imperfect repetition
What is done to test one's language ability?
engage in spontaneous conversation; name items; repeat phrases; follow spoken and written commands; reading passages; writing to dictation
What is paraphasia?
word or syllable substitutions: phonemic; semantic; neologism (nonsense)
What kind of aphasia commonly presents with paraphasic errors?
Fluent aphasia, especially Wernicke's aphasia
What are symptoms of Broca's aphasia?
nonfluency, use of few words, comprehension is preserved, occasionally with right hemiparesis bc. Broca's is near the primary motor cortex
What are the symptoms of Wernicke's aphasia?
fluent speech with few meaningful words, poor comprehension
What is prosody?
the semantic and emotional meaning conveyed by different vocal pitch, inflection, melody, or tone of speech; loss of aprosodia is associated with lesions of the nondominant hemisphere
What is necessary for the neural plate to form from the neuroectoderm?
an underlying layer of mesoderm formed following the invagination of ectoderm cells during the primitive streak formation of the third week
What three levels of organization is there within the neural plate?
polarity, bilateral symmetry; regionalization
What is the neural plate and how is it formed?
elongated slipper-shaped plate of thickened neuroectoderm, appears at the beginning of the 3rd week of development that are formed due to the underlying mesoderm layer; the cells proliferate and form a stratified epithelium
What is the neural groove?
formed when the neural plate begins to fold inward due to the growth on the lateral margins of the neural plate extending
What is the neural tube?
formed following the fusion of the folds of the neural plate, forming a hollow tube around the 21-22 day embryo; proceeds rostrally and caudally
What are the most common cause of perinatal death?
neural tube defects
Where do neural crest cells arise from and what do they form?
the fusion point of the neural plates forming the neural tube; form the peripheral nervous system while the neuroepithelium forms the CNS; with one exception: peripheral motor neuron develops from the basal floor of the neural epithelim and the axon is sent into the periphery
What is the origin of the peripheral motor neuron?
basal floor of the neural epithelium, not the neural crest cells
What are somites?
38-40 pairs of mesodermal tissue blocks along axis formed beginning on the 17th day; differentiate into sclerotome (skeleton/cartilage); mytome (muscles); dermatome (dermis and subcut. Tissue); innervated by GSA, GSE
What are the three initial vesicles of the CNS?
prosencephalon; mesencephalon; rhombencephalon
What does the prosencephalon develop into?
Telencephalon (cerebral cortex, basal nuclei; lateral ventricle); diencephalon (thalamus, hypothalamus; 3rd ventricle)
What does the mesencephalon develop into?
mesencephalon (midbrain; cerebral aqueduct)
What does the rhombencephalon develop into?
metencephalon (pons, cerebellum; 4th ventricle); myelencephalon (medulla)
What are the three layers of the developing CNS and what does each layer form?
1. central ventricular zone (CNS neurons and glia); 2. mantle layer (gray matter); 3. marginal layer (white matter)
What is the origin of microglial cells?
mesenchymal cell; CNS macrophage derived from mesoderm derived monocytes and integrate into CNS
What four cell types do the neuroepithelial cells differentiate in to?
neuroblasts (immature neuron); Oligodendrocytes (glia); astrocytes (glia); ependymal (line the ventricles)
What is spina bifida occulta?
least severe and most common type of spina bifida; defect in the vertebral arch fusion in sacrolumbar region
What is spina bifida cystica?
protrusion of the spinal cord/meninges along with defect in verebral arch fusion: meningocele; meningomyelocele; or myeloschisis
What is spina bifida cystica with meningocele?
vertebral arch fusion defect in which the meninges project through the vertebral defect forming a sac filled with CSF
What is spina bifida cystica with meningomyelocele?
vertebral arch fusion defect in which the meninges and spinal cord project through the vertebral defect forming a sac
What is spina bifida cystica with myeloschisis?
vertebral arch fusion defect in which an open neural tube lies on the surface of the back
What is rachischisis?
many defective vertebrae formations
What is anencephaly?
failure of the anterior neuropore to close and failure of the brain to develop
What are symptoms of posterior fossa lesion?
HA, nausea, visual disturbance, facial pain, dizziness, hearing loss, dysphagia, ataxia, tremor
What structures pass through the foramen magnum?
spinal cord; spinal accessory nerve; vertebral arteries; venous plexus of verebral canal; anterior and posterior spinal arteries
What are the superior and inferior borders of the posterior fossa?
superior: tentorium cerebelli; inferior: occipital sinus; sigmoid, transverse sinus
What is the dual role of medicine?
prolong life where feasible and appropriate; provide comfort, relieve suffering in untreatable/hopeless conditions
What is the pathophysiological cause of multiple sclerosis (MS)?
immune mediated destruction of normal CNS myelin (demyelinating, not dysmyelinating where the myelin is never formed); white matter plaques slowing axonal conduction
What are some possible etiologies of MS?
environmental (temperate latitudes; viral exposure); autoimmune (Igs directed at CNS myelin enters CNS possible similar structure to virus); hereditary (risk of MS 20x greater in 1st degree relative)
What are the clinical manifestations of MS?
onset in young adulthood (20-40); females to males (2:1); sensory or motor deficits in lower limbs, optic neuritis (blurred optic disc margin); episodic (relapsing-remitting 80%)
What are typical features of MS?
Lhermitte's sign (electric shock sensation down spine into legs or arms); trigeminal neuralgia; internuclear opthalmoplegia (MLF)
What are some ancillary test for MS?
MRI; VEP (see if normal cortical response time); CSF analysis (high IgG, oligoclonal bands; high lymphocytes)
What are the treatments for MS?
no curative: corticosteroids for acute symptoms; interferon Beta, Copolymer taken chronically to lessen cumulative severity of disability; symptomatic treatments
What are the functions of astrocytes?
endfeet surround blood vessels and synapses forming BBB; prevent NT (esp. GABA and glutamate) from diffusing away from synapse and recycle glutamine; regulate ions esp. K+; detox CNS; scaffolding for migration of neurons, source of adhesion molecules if damaged forms glial scar
What are the functions of oligodendrocytes?
myelinating cells of CNS, myelinates up to 40-50 nearby axon segments, including optic n. (which is really a tract)
What are the functions of microglia?
macrophages to phagocytize and produce cytokines: IL-1, prostaglandins, and leukotrienes
What is the function of schwann cells?
neural crest derived glial cells which myelinate one axon segment of a peripheral neuron, provide a growth permissive environment for axon, PMP-22 protein necessary for proper myelin formation over/under expression can lead to peripheral neuropathies
What are the functions of microtubules and microfilaments within neurons?
both carry out axonal transport, bidirectional flow of molecules (slow anterograde for growth and fast antero/retrograde for transport); microtubles function in the growth of the axon in length; microfilaments responsible for radial growth of axon
What are the different types of synapses?
axo-dendritic; axo-somatic; axo-axonal; neuromuscular; excitatory/inhibitory; symmetrical/asymmetrical
What are neural stem cells?
progenitor cells that give rise to more differentiated cells but remain in cell cycle: blastocyst is source of true stem cell from embryo or neuroblast; adult from subventricular zone or hematopoietic stem cells