Cerebral Cortex Flashcards
The _______ has roles in language, abstract thinking, adaptation to environment…
Cerebral cortex
_____ makes up most of cortex, 95% total cortex in humans.
Neocortex (6 layers)
The 6 layers (not including the neocortex) of the the cortex are divided into 2 groups, what are they?
Paleocortex = base of brain. 3 layers Archicortex = most of hippocampus. 3 layers
What is the most prevalent type of neuron?
The pyramidal cell
Describe Pyramidal cells…
Have long axons to other cortical area and subcortical sites
- excitatory (glutamate) synapses
- Have dendritic spines
Where is the preferential site of excitatory synapses?
Dendritic spines
* some Forms of intellectual disability may be associated with poor spine development (Autism, Fragile X syndrome)
What is a non pyramidal cell?
All cortical neuron that are not pyramidal cells….No kidding.
- diverse
- tend to have short axons that remain in cortex.
- most make inhibitory (GABA) synapses
What are the 6 layers of the Neocortex from top to bottom?
- molecular layer
- External granular layer
- Internal granular layer
- External pyramidal layer
- Internal pyramidal layer
- Multiform layer.
_____ cortex has fewer projections.
Granular
Areas that send off long axons would have more of what type of cells?
Pyramidal cells
True or Flase. The primary sensory area has lots of pyramidal cells
False, the primary sensory is nearby cortex so no need for long axons of pyramidal cells.
Granular and agranular cortex is _______ distributed.
Irregularly
What are the regions of the Neocortex?
- Primary sensory areas = receives info from thalamic sensory really nuclei.
- Primary Motor areas = Areas that give rise to much of corticospinal tract
- Association areas
- Limbic Areas
Describe the Sensory areas of the Neocortex…
- Have a topographical organization where the body surface, range of frequencies, visual world are mapped out on cortical surface.
- Map is distorted so that highly sensitive areas (fingers) have disproportionately large cortical representation.
Where is the Gustatory cortex?
Frontal lobe (operculum) and Insula
Where is vestibular cortex?
Superior temporal gyrus and posterior Gyrus & insula.
Is the Primary olfactory cortex paleocortical or neocortical?
Paleocortical
The Olfactory cortex consist of what structures?
- Cortex near lateral olfactory tract aka. piriform cortex
- Cortex covering amygdala (periamygdala)
- Small part of parahippocampal gyrus
_______ mediate higher function mental functions such as Language, art, music etc.
Association Areas
What are the two types of association areas?
- Unimodal association cortex = adjacent to primary area & is devoted to elaborating on business of primary area.
- Multimodal association cortex = High level intellectual functions.
What is the dominant hemisphere?
Hemisphere that produces and comprehends language.
Which side dominance is rare?
Right hemisphere is rare, most people are left dominance.
What is the Planum Temporale?
Part of superior temporal gyrus post. to primary auditory cortex.
What are the Perisylvian language areas?
- Broca’s area in inf. froantl gyrus.
- Wernicke’s area in post. part of superior temporal gyrus, continuing into planum temporale and inferior parietal lobule.
______ is inability to use language.
Aphasia
Broca’s and Wernike’s areas provide framework for two broad types of aphasia depending on how easily words are produced. What are they?
- Fluent aphasia can speak and write, but its “word salad” = not correct order.
- Nonfluent can’t express words.
________ can’t talk.
Broca’s aphasia
_____ won’t stop talking but doesn’t make sense.
Wernike’s aphasia
Wernikie’s area is a ________ on Broca’s area.
A check
True or false, Damage to Broca’s area affects language comprehension.
False, language comprehension is unaffected.
What is prosody?
So-called musical aspects of speech produced in right hemisphere.
________ produces prosody.
Right inferior frontal gyrus.
What is the symptom of Motor aprosody?
Cant convey authority, anger, etc in speech.
Damage to what areas causes Agnosia?
Association areas and Unimodal areas
What are the symptoms of Agnosia?
Inability to recognize faces, perceive movements.
______ monitor relationships of body with outside world.
Multimodal areas
What are symptoms of right parietal lobe damage?
- patient has trouble with left half of body.
- May deny something is wrong with left limb.
- Ignore left half of body.
What are the symptoms of left parietal lobe damage?
Important for taking sensory information to plan movement accurately.
* Causes Apraxias (lack of action) = unable to preform some actions.
_______ controls activités of other cortical areas, underlies executive functions.
Prefrontal cortex.
What are the two areas of Prefrontal cortex? and what do they do?
- Dorsolateral = over lateral convexity.
- interconnected with parietal association areas.
- Important role in working memory “Keep in mind” problem planning, solving problems, maintaining attention. - Ventromedial = extends to orbitofrontal and anterior cingulate areas.
- Damage makes people impulsive, can’t suppress inappropriate responses/ emotions.
______ interconnect the Cerebral hemispheres.
Commissures
_______ is the predominate interconnection between hemispheres.
Corpus callosum
____ interconnects temporal lobes (inferior), anterior olfactory nuclei.
Anterior Commissure
All parts of the brain receive commissural fibers except _____ & _______.
Hand area of somatosensory & Motor cortex.
Parts of primary visual cortex.
What causes Disconnection syndromes and what are the symptoms?
Can result from white matter damage.
- can write but unable to read.
- cannot read words even thought they wrote it.
How is Alexia without Agraphia possible?
- Language areas on left isolated from all visual input.
