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Cognitive Disorders
Chapter 13
Nature of Cognitive Disorders: An Overview
 Perspectives on Cognitive Disorders
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Cognitive processes such as learning, memory, and
consciousness are impaired
Most develop later in life
 Three Classes of Cognitive Disorders
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Delirium – Often temporary confusion and disorientation
Dementia – Degenerative condition marked by broad
cognitive deterioration
Amnestic disorders – Memory dysfunctions caused by
disease, drugs, or toxins
Delirium: An Overview
 Nature of Delirium
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Central features – Impaired consciousness and cognition
Impairments develop rapidly over several hours or days
Examples include confusion, disorientation, attention,
memory, and language deficits
 Facts and Statistics
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Affects 10% to 30% of persons in acute care facilities
Most prevalent in older adults, AIDS patients, and medical
patients
Full recovery often occurs within several weeks
Medical Conditions Related to Delirium
 Medical Conditions
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Drug intoxication, poisons, withdrawal from drugs
Infections, head injury, and several forms of brain trauma
Sleep deprivation, immobility, isolation, and excessive
stress
 DSM-IV and DSM-IV Subtypes of Delirium
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Delirium due to a general medical condition
Substance-induced delirium
Delirium due to multiple etiologies
Delirium not otherwise specified
Dementia: An Overview
 Nature of Dementia
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Gradual deterioration of brain functioning
Affects judgment, memory, language, and advanced
cognitive processes
Dementia has many causes and may be reversible or
irreversible
 Progression of Dementia: Initial Stages
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Memory impairment, visuospatial skills deficits
Agnosia – Inability to recognize and name objects (most
common symptom)
Facial agnosia – Inability to recognize familiar faces
Other symptoms – Delusions, depression, agitation,
aggression, and apathy
Dementia: An Overview (cont.)
 Progression of Dementia: Later Stages
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Cognitive functioning continues to deteriorate
Person requires almost total support to carry out day-today activities
Death results from inactivity combined with onset of other
illnesses
Dementia: Facts and Statistics
 Onset and Prevalence
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Can occur at any age, but most common in the elderly
Affects 1% of those between 65-74 years of age
Affects over 10% of persons 85 years and older
47% of adults over the age of 85 have dementia of the
Alzheimer’s type
 Incidence of Dementia
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Affects 2.3% of those 75-79 years of age and 8.5% of
persons 85 and older
Rates of new cases appear to double with every 5 years of
age
 Gender and Sociocultural Factors
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Dementia occurs equally in men and women
Dementia occurs equally across educational level and social
class
DSM-IV and DSM-IV-TR Classes of Dementia
 Dementia of the Alzheimer’s type
 Vascular Dementia
 Dementia Due to Other General Medical Conditions
 Substance-Induced Persisting Dementia
 Dementia Due to Multiple Etiologies
 Dementia Not Otherwise Specified
Dementia of the Alzheimer’s Type: An
Overview
 DSM-IV-TR Criteria and Clinical Features
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Multiple cognitive deficits that develop gradually and
steadily
Predominant impairment in memory, orientation,
judgment, and reasoning
Can include agitation, confusion, depression, anxiety, or
combativeness
Symptoms are usually more pronounced at the end of the
day
Dementia of the Alzheimer’s Type: An
Overview (cont.)
 Range of Cognitive Deficits
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Aphasia – Difficulty with language
Apraxia – Impaired motor functioning
Agnosia – Failure to recognize objects
Difficulties with planning, organizing, sequencing, or
abstracting information
Impairments have a marked negative impact on social and
occupational functioning
 An Autopsy Is Required for a Definitive Diagnosis
Alzheimer’s Disease: Some Facts and Statistics
 Nature and Progression of the Disease
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Deterioration is slow during the early and later stages, but
rapid during middle stages
Average survival time is about 8 years
Onset usually occurs in the 60s or 70s, but may occur
earlier
 Prevalence of Alzheimer’s Disease
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Affects about 4 million Americans and many more
worldwide
Prevalence is greater in poorly educated persons and
women
Prevalence rates are low in some ethnic groups (e.g.,
Japanese, Nigerian, Amish)
Vascular Dementia: An Overview
 Nature of Vascular Dementia
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Progressive brain disorder caused by blockage or damage to
blood vessels
Second leading cause of dementia next to Alzheimer’s
Onset is often sudden (e.g., stroke)
Patterns of impairment are variable, and most require
formal care in later stages
 DSM-IV and DSM-IV Criteria and Incidence
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Cognitive disturbances that are identical to dementia
Unlike Alzheimer’s, obvious neurological signs of brain
tissue damage occur
Incidence is believed to be about 4.7% of men and 3.8% of
women
Causes of Dementia: The Example of
Alzheimer’s Disease
 Current Neurobiological Findings
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Neurofibrillary tangles – Occur in all brains of Alzheimer’s
patients
Amyloid plaques – Accumulate excessively in brains of
Alzheimer’s patients
The role of amyloid proteins (apoE-2, apoE-3, and
apoE-4)
Brains of Alzheimer’s patients tend to atrophy
 Multiple genetic abnormalities implicated in
Alzheimer’s
Summary of Cognitive Disorders
 Cognitive Disorders Span a Range of Deficits
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Attention, memory, language, and motor behavior
Causes include medical conditions, drug use, or
environmental factors
 Most Cognitive Disorders Result in Progressive
Deterioration of Functioning
 Few Treatments Exist to Reverse Pattern of Damage
and Resulting Deficits
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Depression common
Family support may be crucial