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compare cortex of temporal lobe to the rest of the brain

The six-layered neocortex makes up most of the cortical surface, but the hippocampus in the temporal lobe is comprised of phylogenetically older three-layered allocortex


Functions of frontal lobe

Voluntary movement, Language fluency (left), Motor prosody (right), Comportment , Executive function , Motivation


functions of parietal lobe

Tactile sensation, Visuospatial function (right), Attention (right), Reading (left), Writing (left), Calculation (left)


functions of temporal lobe

Language comprehension (left), Sensory prosody (right), Memory (hippocampus) , Emotion
Language comprehension (left), Sensory prosody (right), Memory (hippocampus) , Emotion


functions of occipital lobe

Vision, Visual perception, Visual recognition


diffuse vs focal cortical lesions

diffuse: Alzheimers and hypoxic injury. Focal: vascular disease (stroke), traumatic brain injury (contusion, hemorrhage), and neoplasia (brain tumor).


Cognitive disfunctions from stroke

from aphasia, amnesia, visuospatial impairment, hemineglect, agnosia, and a host of related syndromes


What kind of lesions are seen with tramatic brain injury

Along with the diffuse effects of brain injury, known as diffuse axonal injury that occurs in the white matter, a wide range of focal cortical lesions are seen. Contusions are common in frontal/temporal lobes


What kind of lesions are seen with brain tumors

Often present with focal cognitive dysfunction. Benign tuors do not invade brain, while malignant tumors cause infiltration.


What does damage to Broca's area result in?

Damage to brocas area in the left frontal lobe causes Aphasia.


What is motor aprosody

Lesions to the right frontal lobe (in the same region as where Broca's area is on the left)- causes an inability to inflect speech with emotion


What are the three frontal lobe syndromes

disinhibition from orbitofrontal lesions, executive dysfunction from dorsolateral prefrontal lesions, and apathy from medial frontal lesions. These syndromes are all more florid and persistent with bilateral lesions.


What is disinhibition

Disinhibition is a disorder of comportment, whereby a person can no longer adequately integrate limbic drives into an appropriate behavioral repertoire. Irritability, loss of empathy, impulsivity, hypersexuality, hyperphagia, and even violence can be sequelae.


What does executive dysfunction look like

Defects in the capacity to plan, carry out, and monitor a sequential goal-directed action.


What is apathy

loss of motivation, and more severe forms are known as abulia and akinetic mutism. In these cases, an erosion of initiative may be so dramatic that it seems the individual’s will has been diminished.


Damage to Wernickes area causes what?

Wernicke’s aphasia, in which auditory comprehension is impaired because of a lesion in the posterior region of the left superior temporal gyrus


What is sensory aprosody and what causes it

Diminished ability to comprehend emotional inflection of speech. Due to a lesion in the right hemisphere analogue of Wernickes area (superior temporal gyrus)


Where is the hippocampus and what is its function

tempral lobe- functions in new learning. Damage to this area causes amnesia (new learning deficity)


Limbic system- location and function

Located in temporal lobe and diencephalon- functions in emotion


temporal lobe epilepsy symptoms

deepened emotion, hypergraphia, personality alterations, due to changes in temporal lobe/limbic system


What is hemineglect

failure to report, respond to, or orient to sensory stimuli that cannot be explained by primary sensory dysfunction. Occurs after damage to parietal lobe. Rigth parietal hemineglect can cause inattention to left side of body or extrapersonal space. Left parietal hemineglect causes a disabling disorder of cognition


compare the right vs left pareital lobes capacity to attend to space

lThe right hemisphere has the capacity to attend to both sides of space, whereas the left can only attend to the contralateral space


What are the occipitotemporal and occipitoparietal cortices functions

the occipitotemporal is the “ventral stream” or “what” system. occipitoparietal is the “dorsal stream” or “where” system


Visual agnosia vs visual field defect

Visual agnosia is a recognition deficit due to damage to the ventral or dorsal stream. Can include object agnosia (left occipitotemporal lesions), face agnosia (right occipitotemporal lesion). Visual field deficits produce an absence of vision, while visual agnosia means visual image is seen but not recognized


What is cerebral disconnection

Lesions disconnect one part of brain from another


Example of linguistic disconnection

conduction aphasia


What is alexia

stroke damages left occipital lobe and splenium of corpus callosum. This disconnects the visual system from language system, so person can write but not read.