Neuro Exam 2.4

  1. What type of matter is the semioval center of the telencephalon?
    white matter
  2. The semioval center of telencephalon is white matter w/in what structure?
    cerebral hemispheres
  3. What is the semioval center made of?
    cellular processes (myelinated axons and dendrites)
  4. Where is the the semioval center?
    extends between cerebral cortex, basal ganglia, and ventricular system
  5. What are the types of fibers in the semioval center?
    • commissural fibers
    • association fibers
    • projection fibers
  6. What do the commissural fibers do?
    connect corresponding cortical regions of the two hemispheres
  7. What are the types of commissural fibers?
    • corpus callosum
    • anterior commissure
    • posterior commissure
  8. What does the corpus callosum look like?
    overturned canoe
  9. Which type of commissural fibers is the largest?
    corpus callosum
  10. What is the corpus callosum?
    millions of fibers that are a primary means of communication between right and left hemispheres
  11. What are the parts of the corpus callosum?
    • rostrum
    • genu
    • body
    • splenium
  12. Rostrum of corpus callosum:
    connects frontal lobes
  13. Genu of corpus callosum:
    connects frontal lobes
  14. Body of corpus callosum:
    connects frontal and parietal lobes
  15. Splenium of corpus callosum:
    connects temporal and occipital lobes
  16. What is the largest portion of the corpus callosum?
  17. Directional terms
    towards the nose
  18. Directional terms
    towards the tail
  19. Where is the anterior commissure?
    crosses midline rostrally through the fornix to connect portions of temporal lobe
  20. The anterior commissure is part of what pathway?
    olfactory pathway
  21. Is the posterior commissure in the telencephalon or diencephalon?
  22. Posterior commissure:
    visual reflexes that rely on optical info
  23. What does the posterior commissure connect?
    interconnects superior calliculi and pretectum of the midbrain (reciprocal pathways)
  24. What do association fibers connect?
    cortical regions in same hemisphere
  25. What are the types of association fibers?
    • short association fibers
    • long association fibers
  26. How are short association fibers named?
    not specifically named
  27. What do short association fibers do?
    arch the floor of each sulcus to connect adjacent gyri
  28. Are long association fibers reciprocal?
    always reciprocal
  29. What does reciprocal mean?
    runs both ways
  30. What are long association fibers?
    cables that connect cortical regions in different lobes w/in same hemisphere
  31. Fasciculus:
    named long association fibers that form bundles (reciprocal)
  32. What are the types of fasciculus?
    • uncinate fasciculus
    • arcuate fasciculus
    • cignulum fasciculs
  33. Uncinate fasciculs:
    frontal lobe to temporal lobe
  34. What is another name for the arcuate fasciculus?
    superior longitudinal fasciculus
  35. Arcuate fasciculus:
    • frontal, temporal, and occipital lobes
    • major fasciculs that connects Broca's and Wernicke's area
  36. Cingulum fasciculus:
    • primary association bundle on medial side of hemisphere of brain; connects parietal, temporal, and frontal lobes
    • can be surgically removed to decrease pain
  37. Deep to the insula are 2 association areas:
    • external capsule
    • extreme capsule
  38. What are the external and extreme capsules?
    white matter structures that contain association fibers deep to insula
  39. What is the thin band of grey matter b/w the external and extreme capsules called?
  40. Superficial to deep, the sequence of association structures:
    insula -> extreme capsule -> claustrum -> external capsule -> corpus striatum -> internal capsule
  41. What is the claustrum a part of?
    basal ganglia
  42. What is the corpus striatum a part of?
    basal ganglia
  43. Projection fibers are mostly axons that converge on the:
  44. What do projection fibers connect?
    one specific part of the cerebral cortex and another specific part of the CNS (and vice versa)
  45. Are projection fibers reciprocating?
  46. Where do projection fibers project?
    • to different places
    • (unlike commissural fibers; not in same hemisphere like association)
  47. Afferent projection fibers:
    going to cortex
  48. Efferent projection fibers:
    leaving cortex
  49. Corona radiata:
    radiating mass of afferent/efferent projection fibers going into and out of the brain stem (everything has to narrow when passing through brain stem)
  50. Internal capsule:
    • compact band of efferent and afferent projection fibers formed rostrally
    • condensed area that allows fibers to narrow and go into brain stem or widen to go out of brain stem
  51. What is the appearance of the internal capsule?
    white 'H'
  52. Where is the internal capsule?
    corpus striatum in a transverse section of the brain
  53. What does the internal capsule contain?
    • anterior limb
    • genu (transition)
    • posterior limb
  54. What are the boundaries of the internal capsule?
    • flanked medially and laterally by the basal ganglia
    • medially by head of caudate nucleus
    • laterally by putamen
  55. What does it mean that the internal capsule is somatotopically organized?
    damage to specific part causes a specific impairment that it controls
  56. What are the limbs does the internal capsule form?
    • anterior
    • posterior
  57. What does the anterior limb separate?
    partially separates caudate nucleus and putamen
  58. The caudate nucleus and putamen are what type of structures?
    basal ganglia
  59. What is the anterior limb medially?
    caudate nucleus of basal ganglia
  60. What is the anterior limb laterally?
    putamen of basal ganglia
  61. What types of fibers does the internal capsule contain?
    afferent and efferent fibers
  62. What percent of the anterior limb fibers are afferent?
  63. What do afferent anterior limb fibers have?
    sensory structure
  64. Thalamocortical projection fibers:
    afferent projection fibers that originate in thalamus and are projected to various parts of the cortex
  65. What happens if thalamocortical afferent projection fibers are damaged?
    sensation is affected
  66. What percentage of the anterior limb fibers are efferent?
  67. Frontopontine projection fibers:
    efferent projection fibers that come from frontal lobe (cortex) and travel to pons
  68. What is the posterior limb of the internal capsule?
    motor limb
  69. What is the medially boundary of the posterior limb?
  70. What is the lateral boundary of the posterior limb?
    globus pallidus
  71. What does the posterior limb contain?
    afferent and efferent fibers
  72. What are the afferent (sensory) fibers of the posterior limb?
  73. What percentage of posterior limb fibers are afferent?
  74. What percentage of posterior limb fibers are efferent?
  75. Where do the efferent motor fibers of the posterior limb originate?
    from cerebral cortex to nuclear masses in brain, brain stem, and spinal cord
  76. What are the efferent motor fibers of the posterior limb called?
    corticofugal fibers
  77. Fugal
    spread out
  78. What are the types of corticofugal fibers in the posterior limb?
    • corticothalamic
    • corticopontine
    • corticobulbar
    • corticospinal
  79. Corticothalamic:
    • efferent posterior limb fibers
    • go to thalamus
  80. Corticopontine:
    • efferent posterior limb fibers
    • go to pons
  81. Corticobulbar:
    • efferent posterior limb fibers
    • go to motor nuclei of CNs in the brain stem
  82. corticospinal:
    • efferent posterior limb fibers
    • go to ventral horns of spinal cord
  83. What does a stroke in the posterior limb cause?
    loss of movement
  84. Genu of internal capsule:
    transition (bent) area b/w anterior and posterior limb
  85. What types of fibers does the genu of the internal capsule contain?
    afferent and efferent fibers
  86. What makes up the fornix?
    commissural and projection fibers
  87. What does the fornix connect?
    telencephalon and diencephalon
  88. How does the fornix connect the telencephalon and diencephalon?
    w/ 2-way reciprocal movement of info (both communicate w/ each other)
  89. What forms the fimbria of the fornix?
    axons of pyramidal neurons of hippocampus
  90. Where is the hippocampus?
    temporal lobe of telencephalon
  91. Fibers spread over the ventricles to form:
    fimbria of fornix
  92. Where do axons of the fimbria proceed?
    forward until they reach the posterior end of the hippocampus
  93. Once the fimbria axons reach the hippocampus, what happen?
    arch beneath splenium of corpus callosum
  94. What do the fimbria axons become when they arch beneath splenium of corpus callosum?
    crura of the fornix
  95. Is the crura of the fornix unilateral or bilateral?
    bilateral structure
  96. The crura of the fornix converge and form:
    body of fornix
  97. Between the two converging crura is a thin sheet of tissue called:
    fornical commissure
  98. What is another name for the fornical commissure?
    hippocampal commissure
  99. What type of fibers are found in the fornical commissure?
    commissural fibers
  100. Where is the body of the fornix?
    runs forward under corpus callosum to rostral margins of the thalamus
  101. The body of the fornix bifurcates and forms:
    2 anterior columns of the fornix
  102. The anterior colums of the fornix arch:
  103. Half of the anterior column fibers descend behind what?
    anterior commissure
  104. The half of the anterior column fibers that descend behind the anterior commissure are called:
    postcommissural fibers
  105. The postcommissural fibers terminate in what?
    thalamus and mammillary bodies of hypothalamus
  106. The other half of anterior column fibers descend in front of what?
    anterior commissure
  107. The half of anterior column fibers that descend in front of then anterior commissure are called:
    precommissural fibers
  108. Precommissural fibers terminate where?
  109. What is the function of the fornix?
    • major input/output structure associated w/ limbic system
    • allows communication of the telencephalon with diencephalon for emotional responses
  110. What is the limbic system?
    cortical and subcortical structures which are active w/ emotions and visceral and behavioral responses associated w/ those emotions
  111. What is the limbic lobe?
    collection of specific structures in telencephalon/diencephalon
  112. What are the parts of the limbic lobe?
    • hippocampal formation
    • amygdaloid nuclear complex
    • anterior nucleus of thalamus
    • hypothalamus
  113. Where is the hippocampal formation?
    temporal lobe
  114. What are the parts of the hippocampal formation?
    • gentate gyrus
    • hippocampal gyrus
    • parahippocampal gyrus
  115. Where is the amydaloid nuclear complex?
    • limbic lobe
    • temporal lobe
  116. What is the amygaloid nuclear complex?
    • memory stored and processed
    • memories are a big part of emotions
  117. Where is the anterior nucleus of thalamus?
    part of limbic lobe in diencephalon
  118. Where is the hypothalamus?
    part of limbic lobe in diencephalon
  119. What is the hypothalamus?
    • ANS
    • controls visceral responses (tears, sweat, etc.)
  120. What are the connecting pathways of the limbic system?
    • fornix
    • stria terminalis
    • mammilothalamic tract
  121. What does the fornix connect?
    telencephalon to diencephalon
  122. What is the stria terminalis?
    • lateral border of diencephalon
    • reciprocal connection b/w amygdala and hypothalamus
  123. What does the mammilothalamic tract connect?
    mammillary nuclei of hypothalamus and thalamus
Card Set
Neuro Exam 2.4
review of neuro lecture 4 for exam 2