chapter 14 cognitive disorders

7/29/2019 Chapter 14 Cognitive Disorders

1/43

Cognitive Disorders

Chapter 14


2/43

Cognitive Disorders

Cognitive Disorders: Behavioral disturbances that

result from transient or permanent damage to the

brain.

Affect thinking processes, memory, perception,consciousness, etc. caused by brain dysfunction

DSM-IV-TR categories:

Dementia

Delirium

Amnestic Disorders

Cognitive Disorders Not Otherwise Specified


3/43

Cognitive Disorders

Diagnosis is often a process of elimination

Possible causes: Aging, trauma, infection, loss ofblood supply, substance abuse, and biochemical

imbalance.Cognitive, emotional, and behavioral symptoms

Prevalence: ~1% for severe disorders, 6% for milddisorders

Severe impairment: At age 75, the rate is 22 timesthat of persons 18-34

Rate is higher for African Americans than for whiteor Hispanic Americans.


4/43


5/43


6/43

Prevalence of Cognitive Impairment by

Demographic Characteristics


7/43

Cognitive Disorders

The Assessment of Brain Damage

Psychological tests and inventories assess

behavioral responses and functions such as

memory and manual dexterity.

Neurological tests permit direct monitoring of

brain functioning and structure.

Electroencephalograph (EEG)

Computerized axial tomography (CAT) scan

Cerebral blood flow measurement

Positron emission tomography (PET) scan


8/43

Cognitive Disorders


Neurological tests:

Magnetic resonance imaging (MRI):

Produces snapshots of brain anatomyWith patient in magnetic field, radio waves

are used to produce pictures of the brain

without bone obstruction. fMRI produces dynamic pictures


9/43

Cognitive Disorders


Neurological tests:

Each technique has strengths and

weaknesses in costs, benefits, and possible

side effects.

CAT scan is less expensive and faster

than MRI

MRI does not use X-rays and is better at

detecting neoplasms, brain abnormalities

related to seizures, and certain lesions.


10/43

Cognitive Disorders


Initial screening/assessment:

Mental status examination

Specific interview questions about generalfunctioning, personality characteristics, and

coping skills, changes in behavior.


11/43

Cognitive Disorders

Localization of Brain Damage

Overlap of functions complicates assessment.

There is no 1:1 correspondence for specific

physical areas related to specific psychological

functions from brain to brain.

Diaschisis: A lesion in a specific area of the

brain disrupts other intact areas, sometimes in

the other hemisphere.


12/43

Cognitive Disorders

Localization of Brain Damage

Recovery of function:

Redundancy (unused portions of the brain

take up functions of damaged areas).

Plasticity: Undeveloped portions of the brain

substitute for damaged portions.

Plasticity and compensatory reorganizationmay improve functioning in one area at the

expense of another function.


13/43

The Major Areas of the Brain


14/43

Brain Areas and the Functions They Control


15/43

Cognitive Disorders

The Dimensions of Brain Damage

Brain damage is evaluated on a continuum:

Mild to moderate to severe

Endogenous versus exogenous causes

Diffuse versus specific damage

Acute versus chronic conditions


16/43

Cognitive Disorders

Diagnostic Problems

Overlap with symptoms of psychological disorders:

Depression: Neuropsychological tests show similar

characteristics.

Tests may not show clear distinction betweencognitive disorders and schizophrenia.

If a general medical condition and mood disorder

are related, diagnosis may be mood disorder due togeneral medical condition

Impairment may show up where none exists if there

is a monetary motive (e.g., lawsuit).


17/43

Cognitive Disorders

Diagnostic Problems

Are symptoms due to CNS damage or some othercausal agent (e.g., a toxin)?

A person with brain damage may be diagnosed as

having a psychological disorder.Age-related misdiagnosis may be due to reduced

sensory acuity, performance anxiety, fatigue, failure tounderstand test instructions, or lack of agreement

between different measures of cognitive functioningElderly may score poorly on Halstead-Reitan

Neuropsychological Test Battery but well on WAISand daily functioning.


18/43

Types of Cognitive Disorders

Dementia: Syndrome characterized by memoryimpairment and cognitive disturbances, suchas:

Aphasia: (Language disturbance)Apraxia: Inability to carry out motor activities

despite comprehension and motor function

Agnosia: Failure to recognize/identify objectsdespites intact sensory function

Thought disturbances: Planning andabstraction


19/43


Dementia:

Causes may include general medical conditions,

substance use, multiple etiologies, and other

causes not specified.Prevalence:

1.5 million Americans have severe dementia, 1-5

million have mild-moderate forms5-7% over age 65; greater than 20% over age 85

2-4% have Alzheimers


20/43


Dementia:

Associated disorders:

Alzheimers, vasculardisease, normal

pressure

hydrocephalus,

alcoholism,

intracranial masses,

and Huntingtons

disease


21/43


Delirium:

Disturbance of consciousness and changes incognition, (e.g., memory deficit, disorientation,

language and perceptual disturbances).Rapid development over hours or days

10% of persons over age 65 hospitalized forgeneral medical conditions exhibit delirium

At-risk groups: The elderly and patients recoveringfrom surgery, having preexisting brain dysfunction,in drug withdrawal, with AIDS, and high illnessburden.


22/43


Delirium Tremens: Occurs with alcohol

withdrawal.

Disorientation (self, place, time)

Vivid hallucinations, intense fear

Extreme suggestibility

Tremor in hands, tongue, lipsRapid HR, fever, foul breath

Death as high as 35%, but rare if treated with

drugs like chlordiazapoxide


23/43


Amnestic Disorders: Characterized by memory

impairment as manifested by inability to learn

new information and inability to recall previously

learned knowledge or past events.

Results from insult to central nervous

system:

Head trauma, stroke, Wernickes

encephalopathy (alcohol-induced organic

mental disorder involving thiamine

deficiency).


24/43


Cognitive Disorders Not-Otherwise-Specified:

Cognitive disorders that do not meet the criteria

for dementia, delirium, or amnestic disorder.


25/43


26/43


27/43

Etiology of Cognitive Disorders

Brain Trauma: Physical wound or injury to the

brain.

Concussion: Mild brain injury, typically

caused by a blow to the head.

Contusion: The brain is forced to shift slightly

and press against the side of the skull.

Laceration: Brain tissue is torn, pierced, or

ruptured.


28/43

Etiology of Cognitive Disorders

Thomas E. Witte/NewSport/CORBIS

ATLANTA

PRO WRESTLER CHRIS BENOITSUFFERED BRAIN DAMAGE FROM HIS YEARS IN

THE RING THAT COULD HELP EXPLAIN WHY HE

KILLED HIS WIFE, SON AND HIMSELF, A DOCTOR

WHO STUDIED BENOIT'S BRAIN SAID WEDNESDAY.

THE ANALYSIS BY DOCTORS AFFILIATED WITH THE

SPORTS LEGACY INSTITUTE SUGGESTS

REPEATED CONCUSSIONS COULD HAVECONTRIBUTED TO THE KILLINGS AT BENOIT'S

SUBURBAN ATLANTA HOME.

FoxNews.com 9-5-07


29/43

Aging and Disorders Associated with Aging

Cerebrovascular Accident (stroke): Sudden

stoppage of blood flow to a portion of thebrain, leading to loss of brain function.

Causes: burst blood vessels (25%),

narrowing of blood vessels

(atherosclerosis), or blocked blood

vessels.

Cerebral Infarction: death of brain tissue

from decreased supply of blood to tissue. Vascular Dementia: Uneven deterioration of

intellectual abilities resulting from several

cerebral infarctions.


30/43


Memory loss in older people:

Alzheimer's

Brain cell deterioration, which may be mitigated in

cognitively active persons

People that remain cognitively tend to remain

relatively free of dementia and Alzheimers

Vascular dementiaOccasional loss due to normal aging process (not

indicative of dementia)

Medications


31/43


Fluid abilities decline with age (novel problems,

creativity); acquired knowledge remains stable

75% of elderly retain sharp mental functioning, 10-

15% have mild-moderate memory loss.


32/43



33/43


Cross-Sectionalmethod suggestsdecline

Longitudinal

method suggestsmore stability



34/43


Alzheimers Disease

Alzheimers Disease: Dementia in which braintissue atrophies, leading to markeddeterioration of intellectual and emotional

functioning.Accounts for 80% of dementia in the elderly

Prevalence: 8-15% for people older than 65

Early symptoms: Memory dysfunction,irritability, cognitive impairment

Later symptoms: Social withdrawal,depression, apathy, delusions, impulsivebehaviors, neglect of personal hygiene



35/43


Alzheimers Disease

Death usually occurs within 5 years of onset; 4th

leading cause of death in the U.S.

Atrophy of cortical tissue in the brain:

Neurofibrillary Tangles: Abnormal fibers that appearto be tangles of brain tissue filaments.

Senile Plaques: Patches of degenerated nerve

endings.



36/43


Alzheimers Disease

Etiology: Unknown (hereditary or environmental

factors)

Explanations: Reduced ACTH, repeated head

injuries, infections and viruses, decreased cerebralblood flow, plaques and tangles (chromosome 21),

aluminum, genetic anomalies

Protective factors to delay onset: Genetic

endowment with ApoE-e2 allele, higher

education/occupation, NSAIDs, estrogen

replacement therapy, vitamin E


37/43

Other Diseases and Conditions of the Brain

Parkinsons Disease: Progressively worseningdisorder with muscle tremors, stiff, shufflinggait, lack of facial expression, social withdrawal,

possibly dementia and depressionPrevalence: 0.1%, 1-2% over the age of 65

Causes: brain infection, cerebrovascular

disorders, brain trauma, carbon monoxidepoisoning, genetic predisposition, otherunknown causes

Associated with lesions in the motor area of

brainstem and lower dopamine levels


38/43


AIDS (Acquired Immunodeficiency Syndrome)

Dementia may be due to: AIDS virus

reaching the brain, compromised immune

functioning, effects of knowing one has AIDS,

medications

Neurosyphilis (general paresis): Spirochete

Treponema pallidum

Encephalitis (sleeping sickness): Brain

inflammation caused by viral infection.


39/43


Meningitis: Inflammation of meninges

(membrane surrounding the brain and spinal

cord)

Bacterial, viral, and fungal

Huntingtons Disease: Genetically transmitted

degenerative disease; involuntary twitching

movements and eventual dementia and death.

50% of offspring of affected person develop it

Prevalence: 5-7 per 100,000 population


40/43


Cerebral Tumors: Mass of abnormal tissue growing

within the brain causing disturbances of

consciousness, mild dementia, problems of thinking,

mood changes. Epilepsy: Intermittent/brief periods of altered

consciousness often accompanied by seizures or

excessive electrical discharge from brain cells.

1-2% of U.S. population has seizures at some point

in their lives

Use of psychoactive substances

Cognitive Disorders


41/43

Cognitive Disorders

Treatment Considerations

Major interventions: Surgical, medical,

psychological, and environmental.

Comprehensive: Medication, rehabilitation,

therapy, and environmental modifications.

Surgical: Remove tumors, relieve pressure

caused by tumors, restore ruptured blood

vessels.

Psychotherapy: Help patients deal with

emotional aspects of the disorders.

Cognitive Disorders


42/43

Cognitive Disorders


Medication: Prevent, control, reduce symptoms; also

control accompanying emotional problems.

Side effects: Decrease in speed of motor

responding; tremors; weight gain; swollen gumsAlzheimers: Acetylcholinesterase inhibitors; anti-

inflammatory medications reduce risk.

Current treatment goals: Delay onset of symptoms,

slow progression, improve symptoms, reduce

morbidity, modify risk factors, prevent disease.

Cognitive Disorders


43/43

Cognitive Disorders


Environmental interventions:

Modify patients environment to preserve

sense of independence and control.

Continued social contacts

Diversions

Tasks to provide sense of contributing

Caregiver support:

Education about disease and proper care

chapter 14 cognitive disorders

Documents