Chapter 19 Neuro

normal melodious intonation of speech that conveys the meaning of sentence structure

impairments in reading

impairments in writing **in patients with aphasia it is always present

lesion in inferior parietal lobule of the language-dominant hemisphere

lesion in the dominant occipital cortex extending to the posterior corpus callosum (often PCA infarct)

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acalculia
right-left disorientation
finger agnosia

inability to carry out an action in response to verbal command in the absence of any comprehension deficit, motor weakness, or incoordination

severe apraxia of the speech articulatory apparatus without a language disturbance

bilateral lesions of the primary auditory cortex in Heschl's gyrus

lesion in the right parietal or frontal cortex

in a pt with hemineglect; erroneously report the location of a stimulus given to the left side of the body as being on the right

patient inappropriately moves the normal limb when asked to move the neglected limg

limb movements impaired when the limbs are located in the neglected hemispace

lack of awareness of the illness **not unique to right hemisphere lesions

aware that they have severe deficits yet show no emotional concern or distress about it

deny that the left half of their body belongs to them

patients insist that their friends or family members have all been replaced by identical looking imposters

patients believe that different people are actually the same person who is in disguise

patients believe that a person, place or object exists as two identical copies

frontal lobes and at the parieto-occipitotemporal junctions

Left

language dysfunction, even in left-handed individuals

certain nonverbal functions and is more important for complex visual spacial skills, emotional significance to events, and music perception

marked inattention to the contralateral side, even in individuals who are right hemisphere dominant for language

impairments of lanugage, detailed analytical abilities, and complex motor planning (praxis)

impairments of spatial attention and complex visual-spatial abilities, especially those involving spatial orientation and perception of overall gestalt

interpreting perceptual data and assigning meaning to sensory info

planning, control, and execution of actions

superior bank of the Sylvian fissure in the temporal lobe

initial steps of language processing that enables certain sequences of sounds to be identified and comprehended

corresponds to Brodmann's area 22; encompasses the posterior two-thirds of the superior temporal gyrus in the dominant hemisphere

motor program that activates particular sequesnce of sounds to produce words and sentences

corresponds to Brodmann's areas 44 and 45; opercular and triangular portions of the inferior frontal gyrus in the dominant hemisphere

via a subcortical white matter pathway called the arcuate fasciculus; also polysynaptic connections along the intervening peri-Sylvian cortex

contained in posterior tempoparietal areas and used to map sounds to meaning for both comprehension and production

first reaches primary visual cortex in the occipital lobes, processed in visual association cortex, travels anteriorly via the angular gyrus to reach the language areas

may be difficult to judge the intended expression imparted by a tone of voice

cerebral infarct

infarct in the territory of the left MCA superior division

decreased fluency of spontaneous speech; also lack prosody (normal melodic tone)

disconnection of Broca's area from Wernicke's area

dysarthria, right hemiparesis affected the face and arm more than the leg

smaller lesions confined to the region of the frontal operculum

lesion of wernicke's area and adjacent structures in the dominant temporoparietal lobes

infarct in the left MCA inferior division territory

contralateral visual field cut, especially of the right upper quadrant due to involvement of the optic radiation

global aphasia

mixed transcortical aphasia

Broca's aphasia

transcortical motor aphasia

Wernicke's aphasia

transcortical sensory aphasia

conduction aphasia

anomic aphasia

infarct in the peri-Sylvian area that interrupts the arcuate fasciculus or other pathways in the area of the supramarginal gyrus that connect the two

watershed infarct; spare broca's area, wernicke's area, and interconnections but damage other language areas in the frontal or temporoparietal cortices

ACA-MCA watershed infarct; destroys connections to other regions of the frontal lobe that are needed fro broca's to function but peri-sylvian connections left intact

MCA-PCA watershed infarct; connections to structures in parietal lobe and temporal lobe that are needed for Wernicke's area to function are destroyed; peri-sylvian left intact

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legions in the inferior parietal lobule of the dominant hemisphere

lesion in the dominant occipital cortex extending to the posterior corpus callosum, often a PCA infarct

lesions of the dominant inferior parietal lobule in the region of the angular gyrus

dominant inferior parietal lobule in the region of the angular gyrus

small lesion of the dominant frontal operculum restricted to Broca's area

bilateral lesions of the primary auditory cortex in Heschl's gyrus (cannot identify a dog barking)

infarct in the auditory area of the dominant hemisphere that extends to subcortical white matter to cut off the input from the other hemisphere

right hemisphere unable to access language function in the left hemisphere; agraphia of L hand, inability to name objects in L hand, inability to read in the L hemifield

medial and intralaminar thalamic nuclein; projections in the upper brainstem, hypothalamus, and basal forebrain; cingulate gyrus, medial and lateral fronto-parietal association cortex

prominent and long-lasting deficits in attention to the contralateral side

parietal association cortex at the junction of the parietal, temporal, and occipital lobes in non-dominant hemisphere

ventral occipital, temporal, and prefrontal

dorsal occipital, parietal, and prefrontal cortex

direectly in the dorsal stream, analyzing location and movement of visual objects in space

infarcts of the R parietal or R frontal lobes

infarcts of the cingulate gyrus, thalamus, basal ganglia, or midbrain reticular formation

acute frontal or parietal lesions

severe personality and emotional changes; bland or apathetic, decreased alertness and attention, irritability

deficits in visual-spatial memory

uncinate fasciculus

cingulate gyrus and parahippocampal gyrus

mediodorsal nucleus

head of the caudate nucleus

restraint, initiative, order (RIO)

ability to hold limited amt of info in an immediately available store while other cognitive functions are performed

dorsolateral prefrontal cortex

apathetic, lifeless, abulic state

impulsive, disinhibited, poor judgement

involvement of the frontal eye field can cause impaired saccades away from the lesion

subtle asymmetries with a decreased fast phase in one direction

primitive reflexes normally seen in infants such as the grasp reflex, suck, snout, and root reflexes

shuffling, unsteady, magnetic

projects to the parieto-occipital association area to answer the question "where"

projects to the occipitotemporal association cortex to answer the question "what"

primary visual cortex lesions; depends on info transmitted to association cortex by extrageniculatevisual pathways, bypassin the lateral geniculate nucleus and primary visual cortex

processes color and visual form involved in object ideintification

unable to recognize people by looking at their faces

occipitotemporal cortex (fusiform gyrus)

central disorder of color perception

primary visual cortex of the dominant hemisphere extending into the right corpus callosum; is ass'd with alexia without agraphia and right hemianopia

vestibular or lateral medullary dysfunction

lesions of the visual association cortex cause a previously seen object to reappear periodically

trazodone

bilateral lesions of the dorosolateral parieto-occipital association cortex; **CLINICAL TRIAD:
1.) multianagnosia 2.) optic ataxia 3.) ocular ataxia

impaired ability to reach for or point to objects in space under visual guidance, but proprioceptive or auditory cues lead to ability to point

difficulty voluntarily directing one's gaze toward objects in peripheral vision through saccades

dorsolateral parieto-occipital association cortex; ass'd symptoms may include inferior-quadrant visual field cuts, aphasia, hemineglect

MCA-PCA watershed infarcts

peripheral auditory disorders affecting the typmanic membrane, middle ear ossibles, cochlea, or 8th cranial nerve

AV malformations, carotid dissection, extracranial-to-intracranial pressure gradient that is produced by inc. ICP

visual hallucinations caused by visual loss

content and level

upper brainstem, thalamic, hypothalamic, and basal forebrain activating systems, medial and lateral frontoparietal association cortex and cingulate gyrus

1.) selective-focusing on a particular domain
2.) sustained- functions like vigilance, concentration, and nondistractability

pedunculopontine and laterodorsal tegmental nuclie

pontomesencephalic reticular formation

locus ceruleus and lateral tegmental area

dorsal and medial raphe

substantia nigra pars reticularis, ventral tegmental area

prefrontal cortex

motivational factors of attention

directing visual attention toward relevant visual stimuli

ability to combine varios forms of sensory, motor, emotional, and mnemonic information into an efficient summary of mental activity that can potentially be remembered at a later time

acute confusional state in which agitation and hallucinations are prominent

toxic or metabolic disorders, then infection, trauma, and seizures

develop over hours to weeks, have prominent attentional disturbances, tend to wax and wane over the course of hours, have marked slowing on the EEG, and are most often caused by metabolic or toxic disorders, alcohol withdrawl, head trauma, infection, and seizures

develop over months to years, do not fluctuate as rapidly, and early on have less prominent disturbances in attention and a relatively normal EEG

disturbances in langugae, praxis, visual-spatial functions

neurodegenerative conditions for which treatments are not available

conditions that may be reversible

megaloblastic anemia along with subacute combined degeneration of the spinal cord (posterior columns more than corticospinal tracts)

pellagra- dementia, dermatitis, diarrhea (three Ds)

cerebral atrophy, neuronal loss, amyloid plaques, neurofibrillary tangles

1.) medial temporal lobes (amygdala, hippocampal formation, enterohinal cortex)
2.) basal temporal cortex extending over lateral posterior temporal cortex, parieto-occipital cortex, and posterior cingulate gyrus
3.) frontal lobes

insoluble protein core containing B-amyloid, along with apoE, surrounded by abnormal axons/dendrites

intracellular accumulations of hyperphosphorylated microtuble-associated proteins or paired helical filaments known as tau proteins

cleavage at an intracellular location by y-secretase

1.) APP gene (chrom 21)
2.) presenilin 1 gene (chrom 14)
3.) presenilin 2 gene (chrom 1)

donepezil, rivastigmine, galantamine