cerebral cortex Flashcards
What is the role of the cerebral cortex?
- language, abstract thinking, adapt to environment
What type of neuron is the most prevalent in the cortex?
pyramidal cell
___ dendrites travel vertically to the top of the cortex and ___ dendrites travel horizontally.
- apical
- basal
Pyramidal cells have ___ synapses
excitatory (glutamate)
___ are the preferential site of excitatory synapses and are suggested to be the sites of synapses that are selectively modified as a result of learning
dendritic spines
Some forms of intellectual disability may be associated with poor ___ development.
spine
Pyramidal cells axons project to ___ and ___.
- cortical areas
- subcortical sites
Nonpyramidal cells are mostly ___ synapses.
inhibitory (GABA) synapses
Nonpyramidal neurons tend to have short axons that remain in the cortex, and are principal ___ of the cortex.
interneurons.
Areas the send off long axons have more ___.
pyramidal cells
___ project to nearby cortex, so there is no need for long axons and therefore we see fewer pyramidal cells.
primary sensory areas
The neocortical regions are (4)
- primary sensory area
- primary motor area
- association area
- limbic area
___ receive information from thalamic sensory relay nuclei.
Primary sensory areas
___ are areas that give rise to much of the corticospinal tract.
Primary motor areas
What are the parietal lobe functions?
- primary somatosensory cortex (postcentral gyrus)
- Inferior left parietal lobe involved with language comprehension
- spacial orientation and attention
Occipital lobe functions
- Primary visual cortex (in banks of calcarine sulcus)
- visual association cortex involved in higher order visual processing
Bilateral injury to the inferior occipital lobe causes ___. Bilateral injury to the ___ causes motion blindness.
color blindness
occipital temporal junction
What is the function of the temporal lobe?
- Primary auditory cortex
- auditory association cortex
- language comprehension, wernikes area
- higher order visual processing
Primary function of the gustatory cortex
taste. located in the frontal lobe (operculum) and insula
Primary function of the vestibular cortex?
Spacial orientation and self motion perception
The primary olfactory cortex is ___ not neocortical.
paleocortical
The olfactory cortex consists of the ___, ___, and ___.
- piriform cortex
- periamygdaloid cortex
- parahippocampal gyrus
Frontal lobe function
Primary motor cortex
___ is inferior to the frontal gyrus of one hemisphere (usually left) and is responsible for the production of spoken and written language.
Brocas area
The ___ cortex is the rest of the frontal lobe and deals with executive functions (personality, foresight, insight)
prefrontal
Dominent hemisphere is the one that ___ and ___ language. It is most likely on the ___ hand side, even in ___ handed people.
- produce
- comprehend
- left
- left
Cortical language areas are near the ___.
- lateral sulcus
The lateral sulcus extends further posteriorly on the ___ as the planum temporal is larger on the ___.
- right
- left
Part of the superior temporal gyrus posterior to the primary auditory cortex
Planum temporale
Language areas border the ___ sulcus, and stimulates the motor cortex near mouth to produce involuntary grunts and vocalization.
left lateral
Where is Brocas area located?
inferior frontal gyrus
Where is Wernicke’s area located??
posterior part of the superior temporal gyrus, continuing into planum temporale and inferior parietal lobule.
Inability to use language, loss of the use of, or access to symbols humans use as concepts is termed?
aphasia (Brocas and Wernickes provide framework for aphasia)
Describe nonfluent aphasia
- make few written or spoken words but its very difficult to produce words.
- all detail and meaning in sentences is lost
- can comprehend language
- often Brocas area issue
Describe fluent aphasia
- Can write and speak, but words used and sequences of words used in sentences is incorrect
- little to no linguistic content
- Make up new words (neologism)
- Substitute one letter or word for another (paraphasia)
- Difficulty in comprehension
- Often due to Wernicke’s area
Broca’s Damage
- Deprive motor areas of ability to generate language but muscle function normal in other activities
- comprehension of language is unaffected
Wernicke’s damage
- Broca’s is unchecked
- Words generated but no meaning
Muscial aspects of speech or ___ are produced in the right hemisphere
- prosody (specifically right inferior frontal gyrus)
Describe motor aprosody.
Cant convey authority, anger, etc. in speech
Describe sensory aprosody.
Difficulty comprehending the emotional content of speech from others ( right posterior temproparietal region)
Main function of the parietal cortex
- association area posterior to the primary somatosensory cortex
The visual associate cortex, auditory association area, somatosensory area are examples of ___ in the parietal cortex.
unimodal areas
- damage to these can cause sensory specific agnosias
- inability to recognize faces, perceive movement ( visual agnosias)
Multimodal areas are centered in the ___ and monitor relationships of body with the outside world.
intraparietal sulcus
Patient having trouble with left half of body, may deny that something is wrong with left limb, can be convinced that the limb is someone else’s, and can ignore the left half of the body (contralateral neglect) is indicative of ___.
Right parietal lobe damage
Apraxias
“lack of action”
- patients unable to perform some actions
- left parietal lobe damage
The ___ is anterior to the primary and supplementary motor areas and is in charge of executive functions
prefrontal cortex
The prefrontal cortex is interconnected with the ____ of the thalamus.
dorsomedial nucleus
The ___ is the predominate interconnection between hemispheres
corpus callosum
The ___ interconnects temporal lobes inferiorly and anterior olfactory nuclei.
anterior commissure
All parts of brain receive commissural fibers except ___ area of somatosensory and ___ cortex, and parts of ___ cortex.
- hand
- motor
- primary visual
Strokes are a frequent cause of ___ syndromes
disconnection
Alexia without agraphia
- can write but cannot read event though they wrote them
- language areas on left isolated from all visual input
- language areas intact so speech in unaffected.
- left visual cortex damaged by stroke
- right visual cortex intact but corpus callosum damaged
Association bundles
- interconnect areas of one hemisphere
- short: u fibers
- long: tavel to different lobes
Association bundles with long fibers are arranged in distinct bundles. what are some of these bundles?
- superior longitudinal (arcuate fasciculus
- superior occipitofrontal fasciculus (SO)
- inferior occipitofrontal fasciculus (IO)
- Cingulum (C)
- Uncinate fasciculus (U)
