Neuro2 Flashcards
How many neurons are estimated to be in the cortical gray matter?
10 Billion
What 6 layers make up the cortical gray matter?
Molecular External Granular External Pyramidal Internal Granular Internal Pyramidal Multiform
Name 5 types of important cells in the 6 layers of cortical gray matter.
Pyramidal Stellate Fusiform Horizontal cells of Cajal cells of Martinotti
What two directional categories does white matter have in relation to cortical gray matter?
Radial fibers - run toward the cortex
Tangential fibers - run parallel to the cortex
What is the smallest division of functionally-grouped activity within the cortex?
Vertical columns
Vertical columns form:
Functionally specialized areas
Functionally specialized areas of vertical columns are grouped together into anatomically distinct:
Lobes or Cortices
Lobes/cortices can be further grouped into other connected areas in:
Functional circuits
Functional circuits can be connected via what 3 pathways?
Association fibers (intra-hemisphere) Commissural fibers (contralateral hemisphere) Projection fibers (thalamocortical - fibers leave cortex and go ANYwhere other than cortex)
What do association fibers connect anatomically?
to the same hemisphere
What do commissural fibers connect anatomically?
to the opposite (contralateral) hemisphere
Where do projection fibers originate?
The Thalamus
Name 5 important functional areas of the cortex.
Primary Sensory cortices Sensory Association cortices Motor Planning cortices Primary Motor cortices Association cortices
Where is the primary somatosensory cortex?
Post-central gyrus
this is the sensory homunculus
What does a lesion on the somatosensory cortex cause?
Deficit in sensation from the opposite side of the body
hemi-anasthesia contralateral to lesion
Where is the somatosensory association complex?
Superior parietal lobe and supramarginal gyrus
this identifies the object you are feeling
Where is the primary visual cortex?
Cuneus and Lingual gyri
analyzes visual world without association
Where is the visual association cortex?
Medial and lateral occipital gyri
Angular gyrus
Where is the primary auditory cortex?
The auditory association cortex?
Superior Temporal Gyrus/Transverse Temporal gyri
Superior Temporal Gyrus
Wernike’s area is a specialized part of what?
function?
The auditory association cortex in the superior temporal gyrus.
Spoken language comprehension
What do the uncus, piriform cortex, periamygdaloid, and part of parahippocampal gyrus make up?
The Primary Olfactory Cortex
What is Agnosia?
Inability to recognize an object or to interpret sensory stimuli.
Name 3 types of Agnosia.
Tactile
Visual
Auditory
Where does executive function reside?
Frontal lobe
specifically: superior, middle frontal gyri, and medial frontal lobe
What is meant by Executive Function?
refers to all planning (motor, cognitive, emotional)
as well as regulate Affect with sensation
What can be termed a negative sign?
Loss of function (paralysis)
What can be termed a positive sign?
Abnormal function (hallucination)
What does the Limbic association cortex regulate?
Emotions, mood, affect, memory
closely tied to the sense of smell
What would a tumor or stroke cause if it was in the limbic system?
visual and auditory hallucinations
What cortex is involved in sensory integration (including interpretation), problem solving, speech, and spatial processing?
Parietotemporal Association Complex
What can a lesion of the non-dominant (usually right) Parietotemporal association complex cause?
Hemineglect Syndrome on the Left
this won’t effect speech because in most people it is localized in the left hemisphere
Where is the Primary Motor Cortex?
The precentral gyrus
Motor Homunculus
What will a lesion in the primary motor cortex cause?
Paresis (weakness/partial paralysis) in the opposite side.
Where are the Premotor Cortex and the Frontal Eye Fields?
Middle Frontal Gyrus
Where is the Supplemental Motor Cortex?
Superior Frontal Gyrus
