Bio Bases of Bx: Cognitive Disorders Flashcards
Impact of stroke, trauma, tumor depends on 3 factors
- Size
- Specific location
- Cerebral Hemisphere
Aphasia
Language disorder
Resulting from damage or lesion to LEFT Hem
Nature of lang impairment based on location of lesion
Common Aphasias (4)
Broca’s
Wernicke’s
Conduction
Global
Broca’s Aphasia
*Hint: Broca=broken speech
Location: Left FRONTAL, motor strip
Impacts expression of speech
Dysarthia:Speech slow & effortful
Comprehension mostly intact
Wernicke’s Aphasia
*Hint: Garbage in, garbage out
Location: Left TEMPORAL lobe No lang comprehension speak fluently, but nonsense Often unaware they have a problem Considered a receptive/sensory aphasia
Conduction Aphasia
Location: Connection between expressive & receptive speech areas (between broca & Wernicke)
Intact lang comprehension
Fluent speech, but unable to repeat, nonsensical speech
May resemble Wernickes but are able to follow commands b/c they understand
Global Aphasia
Damage to most left cortex
Impairment to fluency, comprehension, repetition, naming, reading & writing
One sided neglect
Damage to one side of brain impacts fx on opposite side of body
Loss of sensation or movement
Ex: forget to dress one side of body, eating food from one side of plate
Apraxia
Inability to carry out purposeful motor mvmts, though no deficit in motor or sensory skills
Muscles & limbs still move, but in wrong position or omit a step of a particular action
Agraphia
Impaired ability to write
Could include spelling, word selection, grammar, spatial arrangement
Left Hem damage to variety of areas
Alexia
Partial or complete inability to read
Most commonly due to stroke
Pure alexia is alexia without agraphia
Prosopagnosia
Inability to recognize familiar face
Typically retrograde & anterograde
Due to injury to the visual assoc cortex
Anosagnosia
Lack of awareness of disability
Ex: Wernickes where ppl don’t recognize they are speaking gibberish
Hydrocephalus
Accumulation of cerebrospinal fluid in brain ventricles, causing increased intracranial pressure
Often caused by malabsorption of CSF
Can be caused by head injuries, tumors, meningitis, or encephalitis
Dementia is characterized by memory impairment + at least one of the following deficits
- Aphasia (language probs)
- Apraxia (motor probs)
- Agnosia (difficulty recognizing objects)
- Executive functioning deficits (planning, organizing, sequencing, abstracting)
True or false: overall rate of dementia is equal in men & women
True
What is the most common form of dementia?
Alzheimers disease; accounts for over 1/2 of cases
True of False: Alzheimers is more common in men
False- women
Alzheimers is a diagnosis of _____, where all other possible medical, neurological, and psychiatric causes are ruled out first
Exclusion- can only be confirmed upon autopsy
Alzheimers stages: Early Phase
Impaired recent memory (forgetting names of items, forget what one is doing, diff problem solving)
Irritability, frustration, anger
Alzheimers stages: Middle Stage
Further impaired memory
Cognitive deficits like aphasia, apraxia, agnosia
Confusion, wandering, socially undesirable bxs
Alzheimers stages: Late Stage
Gait & motor probs
Possibly mute
Alzheimers progresses most rapidly when ____________
onset is early, or before 65 years of age
Etiology of Alzheimers Disease
Genetic component: 1st degree relatives 6x more likely to develop
Brain changes: Senile Plaques & Neurofibrillary tangles especially in hippocampus & amygdala
Changes in neurotrans: Decrease in acetylcholine
Most common medication tx for Alzheimers
Aricept (donepezil)
True or False: Vascular dementia is twice as common in males as females
True
Vascular Dementia
Result of small cerebrovascular accidents, or strokes
Onset abrupt, marked by rapid changes described as step wise due to plateaus followed by further degeneration
Half of ppl dx w/vascular dementia die within __ years of dx
2-3
Tx of Vascular Dementia
Prevention efforts through lifestyle changes
No medications to reverse impact of stroke but aspirin, anticoagulants, antihypertensives frequently prescribed to reduce likelihood of future strokes
Parkinson’s Disease
Movement disorder characterized by: tremor rigidity bradykinesia (slowed initiation of movement) shuffling gait dementia (30 -50% of patients) depression (50-90% of patients)
Etiology of Parkinson’s Disease
Degeneration of neurons in substantia nigra (section of basal ganglia). decrease in dopamine
Tx of Parkinson’s
L-Dopa (levodopa), a precursor to dopamine treats movement component
No tx to slow progression or decrease sxs of dementia
Antidepressants may help with emotional & cognitive fx
Neurotransmitters assoc with Eating Disorders
Serotonin & norepinephrine (implicated in appetite & mood)
Chemotherapy preferred tx for childhood tumors over radiation b/c radiation contributes to:
learning problems & growth deficiencies
Cerebral Palsy most commonly results from
trauma at birth
Dementia due to head trauma
non progressive if result of single head trauma
Huntington’s Disease
Involves basal ganglia, result of autosomal dominant gene
Onset 35 to 45 years, Offspring have 50% chance of being affected
Sxs: personality change, progressive dementia, choreiform mvmts (brisk jerking mvmts of pelvis, trunk, limbs), athetotis (slow writhing mvmts), facial grimaces
Neurotransmitters implicated in Huntington’s
acetylcholine & GABA
Destruction of caudate nuc & putamen results in dec level of GABA (which is produced in bas ganglia), GABA moderates/inhibits production of dopamine. Without it, there is too much dopamine which results in chorea (uncontrollable, irregular muscle mvmts of arms legs & face)
Pick’s Disease
Rare disease, clinically indistinguishable from Alz Disease
Twice as common in women
Onset btwn 50s and 60s
Frontal & temporal lobes affected
Decreased initiative, inappropriate bx, euphoria, explosive temper, poor impulse control, probs w/memory & language
Apraxias & agnosias less common than Alz Dis
Aids Dementia
10-15% of ppl w/AIDS develop
Cognitive sxs-memory, language
Motor Sxs
Behavioral Symptoms-apathy, withdrawal, mood swings,
Dementia due to head trauma
Acute brain injury- delirium or amnestic disorder Closed head (Concussions, Contusions) Open Head
Concussions
most common, neural dysfunction but no cerebral contusion
Often causes anterograde amnesia & retrograde (events just before injury, incident itself but remote events remain intact)
Most common sx: irritability, fatigue, headache, dizziness
Contusions
brain bruises, coup-countercoup injuries (both sides of brain due to impact against skull and backlash)
Temp aphasia, slight hemiparesis, unilateral numbness
Pseudodementia
False dementia- due to depression
Subjective complaints of memory loss may be a sign, with rapid onset & progression
Delirium/Acute Confusional State
Syndrome resulting from disturbances to consciousness
Acetylcholine implicated
Reduced ability to focus, disoriented, memory deficit
Acute onset, fluctuating course, clouded sensorium, reversible if underlying condition treated
Common causes of delirium
infections, metabolic & endocrine disorders, postoperative states, substance intoxication, substance withdrawal
Amnestic Disorders (only memory impaired) most commonly caused by:
head trauma
alcohol abuse
Korsakoff’s Syndrome
Amnestic disorder
caused by chronic thiamin deficiency assoc w/alcoholism
Anterograde amnesia
Retrograde for remote memory of adult life
Results in confabulation
Lack of insight
limited spontaneous conversation
2 Major phases of sleep:
non REM (stages 1 thru 4) REM
When a person is alert & active, ___ waves predominate; during relaxation, ___ waves predominate
beta
alpha
Stages of sleep
Stage 1-brief transitional stage between wake & sleep, theta waves (4 to 8 Hz)
Stage 2- Greatest amt of time during sleep; charac by spindles or rhythmical responses of 12 to 16 Hz
Stages 3 & 4- slow delta waves of 1 to 2 Hz, hard to awaken
REM sleep-follows stage 4, EEG patterns of stage 1 with REM
Tonic Clonic Seizures
Tonic stage- continuous tension or contraction followed by clonic stage (rapid involuntary, alternating muscle contractions, relaxation)
Occur during grand mal seizure
Petit Mal Seizures
Absence seizures, most often in children
Change in level of consciousness, blinking/rolling of eyes, blank stare, slight mouth mvmts, posture retained
Simple Partial Seizures
electrical abnormalities in a focal area of the brain
can affect very small area of body vs half of the body
remain conscious, can recall details
Jacksonian Seizures
Initially localized motor seizure, with spread of abnormal activity to adjacent brain areas
Complex Partial Seizures
Preceded by an aura
Purposeless bx
lip smacking, unintelligible speech
Tests of brain fx & structure (3 types)
PET Scan- show fx capacity for a particular brain region
MRI- Visualization of brain structure
CAT scan- x ray like pics of internal organs of the brain, very clear & accurate
Synesthesia
2 or more senses are connected
seeing music, or smelling colors
General Adaptation Syndrome
Hans Selye’s model of response to severe stress:
Stages
Alarm-sympathetic nervous system activated; lowered resistance to illness
Resistance-alarm reaction subsides, body adapts to stressor, resistance to illness above normal
Exhaustion-response to chronic unremitting stress, sign loss of health
Health Belief Model
Rosenstock
Ind who believe they can control their health are more likely to engage in healthy habits
