Abnormal Psychology

Cognitive Disorders 689

Delirium

Mrs. B.’s cognitive diffi culties emerged gradually over time. Although she forgot ap-

pointments, she never forgot—and was never confused about—who and where she

was. Moreover, she did not experience unusual or rapid changes in consciousness or

in the ability to focus her attention. If she had, these symptoms might have indicated

that she was delirious, as are many residents of nursing homes who

are 75 years old or older (American Psychiatric Association, 2000). In

this section we look at delirium in detail.

What Is Delirium?

Deliriumis characterized by two main symptoms: a disturbance

in consciousness and changes in cognitive functioning, particu-

larly in attention. These symptoms develop rapidly—over hours to

days—and fl uctuate within a 24-hour period. The disturbance in

consciousness is evidenced by decreased awareness of the external

environment; the person may appear “stoned” or seem to be focus-

ing on internally generated stimuli, such as mental images. Atten-

tional problems include diffi culties in focusing on external stimuli

as well as problems in sustaining and shifting attention. A delir-

ious patient may have a hard time understanding a question, or

may have trouble shifting attention to a new question and remain

focused on the previous one. Alternatively, he or she may be dis-

tracted and unable to pay attention to any question.

These attentional problems can make it diffi cult for a clinician

to interview the delirious patient; the clinician must infer the pa-

tient’s mental state from his or her behavior and unusual responses

and then seek information from family members or friends. The

DSM-IV-TR diagnostic criteria are summarized in Table 15.2, and

Case 15.2 describes one woman’s experience with delirium.

Key Concepts and Facts About Normal Versus Abnormal Aging and Cognitive Functioning

• Most aspects of cognitive functioning remain stable during the
  normal course of aging. However, fl uid intelligence and the re-
  lated abilities of processing speed, recalling verbal information
  on demand, maintaining attention, and multitasking do decline
  in older adults. But these declines do not generally impair daily
  functioning.


• Although older adults are less likely than younger adults to
  have a psychological disorder, the disorders that are most
  common among older adults are depression and generalized
  anxiety disorder. A small percentage of adults develop schizo-
  phrenia and have their fi rst psychotic episode after the age of
  44. These disorders can lead to impaired cognitive function-
  ing that may superfi cially resemble symptoms of a cognitive
  disorder.


• Brain injury, most commonly from a stroke, can produce vari-
  ous cognitive defi cits that may resemble those related to psy-
  chological disorders. Among the deficits that may follow a
  stroke or a head injury are aphasia (problems with producing

and comprehending language), agnosia (problems in interpret-

ing what is perceived), and apraxia (problems in organizing

and producing voluntary movements).

• Legally prescribed medications or illegal substances can alter
  awareness, emotional states, and cognitive functioning. A dose
  that is standard for a younger person can adversely affect an
  older adult.

Making a Diagnosis

• Reread Case 15.1 about Maurice Rosen, and determine whether
  or not his symptoms are probably the result of normal aging or
  might indicate a psychological disorder. Specifi cally, list which
  symptoms seem to result from normal aging and which ones
  may indicate a disorder. If you would like more information
  to determine his diagnosis, what information—specifically—
  would you want, and in what ways would the information infl u-
  ence your decision?

Table 15.2 • DSM-IV-TR General Diagnostic Criteria

for Delirium

A. Disturbance of consciousness (i.e., reduced clarity of awareness

of the environment) with reduced ability to focus, sustain, or shift

attention.

B. A change in cognition (such as memory defi cit, disorientation,

language disturbance) or the development of a perceptual distur-

bance that is not better accounted for by a preexisting, established,

or evolving dementia.

C. The disturbance develops over a short period of time (usually

hours to days) and tends to fl uctuate during the course of the day.

D. There is evidence from the history, physical examination, or labo-

ratory fi ndings that the symptoms in Criteria A and B are (one or more

of the below):

1. Caused by medication;


2. Caused by a general medical condition;


3. Developed during substance intoxication;


4. Developed during, or shortly after, a withdrawal syndrome.
   Source: Reprinted with permission from the Diagnostic and Statistical Manual
   of Mental Disorders, Text Revision, Fourth Edition, (Copyright 2000) American
   Psychiatric Association. For more information see the Permissions section.