Cognitive Disorders Chapter 13 Nature of Cognitive Disorders

Cognitive Disorders Chapter 13

Nature of Cognitive Disorders: An Overview n Perspectives on Cognitive Disorders n n Cognitive processes such as learning, memory, and consciousness are impaired Most develop later in life n Three Classes of Cognitive Disorders n n n 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 n Nature of Delirium n n n Central features – Impaired consciousness and cognition Impairments develop rapidly over several hours or days Examples include confusion, disorientation, attention, memory, and language deficits n Facts and Statistics n n n 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 n Medical Conditions n n n Drug intoxication, poisons, withdrawal from drugs Infections, head injury, and several forms of brain trauma Sleep deprivation, immobility, isolation, and excessive stress n DSM-IV and DSM-IV Subtypes of Delirium n n Delirium due to a general medical condition Substance-induced delirium Delirium due to multiple etiologies Delirium not otherwise specified

Dementia: An Overview n Nature of Dementia n n n Gradual deterioration of brain functioning Affects judgment, memory, language, and advanced cognitive processes Dementia has many causes and may be reversible or irreversible n Progression of Dementia: Initial Stages n n 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. ) n Progression of Dementia: Later Stages n n n 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 n Onset and Prevalence n n 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 n Incidence of Dementia n n 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 n Gender and Sociocultural Factors n n 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 n Dementia of the Alzheimer’s type n Vascular Dementia n Dementia Due to Other General Medical Conditions n Substance-Induced Persisting Dementia n Dementia Due to Multiple Etiologies n Dementia Not Otherwise Specified

Dementia of the Alzheimer’s Type: An Overview n DSM-IV-TR Criteria and Clinical Features n n 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. ) n Range of Cognitive Deficits n n n 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 n An Autopsy Is Required for a Definitive Diagnosis

Alzheimer’s Disease: Some Facts and Statistics n Nature and Progression of the Disease n n n 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 60 s or 70 s, but may occur earlier n Prevalence of Alzheimer’s Disease n n n 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 n Nature of Vascular Dementia n n 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 n DSM-IV and DSM-IV Criteria and Incidence n n n 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 n Current Neurobiological Findings n n 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 (apo. E-2, apo. E-3, and apo. E-4) Brains of Alzheimer’s patients tend to atrophy n Multiple genetic abnormalities implicated in Alzheimer’s

Summary of Cognitive Disorders n Cognitive Disorders Span a Range of Deficits n n Attention, memory, language, and motor behavior Causes include medical conditions, drug use, or environmental factors n Most Cognitive Disorders Result in Progressive Deterioration of Functioning n Few Treatments Exist to Reverse Pattern of Damage and Resulting Deficits n n Depression common Family support may be crucial