Cognitive Disorders

Chapter 13

Nature of Cognitive Disorders: An Overview

Perspectives on Cognitive Disorders Cognitive processes such as learning, memory, and

consciousness are impaired Most develop later in life

Three Classes of Cognitive Disorders 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 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

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 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

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 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

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 Cognitive functioning continues to deteriorate Person requires almost total support to carry out

day-to-day activities Death results from inactivity combined with onset of

other illnesses

Dementia: Facts and Statistics

Onset and Prevalence 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

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 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 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 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 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

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 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

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 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 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 Depression common Family support may be crucial