The relationships between age, cognitive functioning and depression seem to be intricate and dauntingly cryptic. One of the most serious obstacles to accurate assessments of cognitive performance of the elderly lies in the overlap between the symptoms of depression and dementia, a mental disorder characterized by the loss of cognitive function, which has made differential diagnosis of dementia and depression an ongoing (and formidable) challenge. Many of the subjective and vegetative symptoms of depression, such as apathy and sleep disturbances, also occur in individuals in the early stages of dementia. Reciprocally, the symptoms of depression include cognitive difficulties with concentration, decision making, and memory. Because depression can be effectively treated in a variety of ways, accurate differential diagnosis is essential. Antidepressants will generally improve the cognitive dysfunction associated with depression but will have minimal effect on organic degeneration.
Accurate diagnosis is most elusive in the early stages of depression and dementia. The traditional methods of delineating between the two have relied on symptoms, psychiatric history, family history of depression, rate of onset, and response to treatment. Decreased appetite is a common symptom of depression, but many Alzheimer’s patients actually report increased eating in the early stages of the disorder. Olfactory problems are frequent in neurodegenerative disorders, but depressed individuals almost never exhibit a decreased sense of smell. Interestingly, the time between onset of symptoms and seeking of treatment may also provide a clue: research has shown that the median duration of cognitive problems before treatment is approximately five years for demented individuals but a scant two months for depressed elderly. This may be reflective of the protracted degeneration of dementia.A considerable amount of research has been devoted to differences in how depressed and demented elderly respond to cognitive testing. In memory tasks, depressed patients have exhibited a tendency towards a conservative response bias and reluctance to guess. Conversely, dementia patients are far more likely to venture an answer even when they are unsure of its accuracy. Typically, elderly depressed subjects perform at a level between that of normal controls and dementia subjects on cognitive test batteries. This suggests that both depression and dementia exacerbate the cognitive declines associated with normal aging and that the difference is one of degree.
The author’s primary purpose is to:(A) discuss problems that arise from a failure to distinguish between depression and dementia
(B) explicate the difficulties in differentiating between dementia and depression in the elderly
(C) contrast the efficacy of cognitive testing with other diagnostic methods
(D) lobby for funding for research into more effective methods of cognitive assessments
(E) describe the cognitive performance of normal, depressed, and demented elderly
Which of the following are cited by the passage as reasons why it is difficult to differentiate between dementia and depression? I. Similar symptoms are manifest in the early stages of both disorders
II. People with dementia have an increased vulnerability to depression
III. Dementia and depression have the same, underlying organic cause.
(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III
Why does the author discuss olfactory impairment in the second paragraph?(A) To bolster his assertion that the symptoms of depression and dementia overlap
(B) To demonstrate that dementia has an underlying, organic genesis while depression does not
(C) To provide a concrete example of a distinguishing symptom of dementia
(D) To illustrate the breadth of symptoms associated with neurodegenerative disorders
(E) To cite an example of sensory impairment common in the elderly
According to the passage, all of the following are ways to distinguish between depression and dementia in the elderly EXCEPT: (A) sensory functioning
(B) less than normal performance on cognitive tests
(C) willingness to guess during cognitive testing
(D) duration of tolerance for symptoms
(E) response to antidepressant medication