Treatment of Communication Impairments in Individuals with Dementia

Abstract

The purpose of this investigation was to determine whether improvement in memory-related communicative deficits associated with Alzheimer's dementia could be obtained from spaced retrieval training (SRT). Two persons with Alzheimer's dementia received SRT on three individually selected communication goals. Results of the study showed generalization of 2 out of 3 goals at 4-weeks post-treatment for both participants.

Introduction

Dementia is a clinical syndrome defined by deterioration of memory and at least one other cognitive function that is severe enough to interfere with daily life activities. Alzheimer's disease (AD) is the most common cause of irreversible dementia characterized by a gradual onset of cognitive deficits that progressively worsen. Memory loss is the hallmark characteristic of Alzheimer's dementia (Chapey, 2001). Alzheimer's dementia is two to three times more common in women than in men. It is the fastest growing and most expensive clinical population in the United States (Brookshire, 2003). An estimated 4 million people in the United States have AD, with as many as 9 million estimated to have the disease in 2040. According to Davis, Massman, and Doody (2001), 5-10% of the population over the age of 65, and as many as 50% of those older than 85, have a diagnosis of AD.

Memory impairment is the major defining symptom of Alzheimer's disease. The functional deficits that individuals with AD experience in communication, activities of daily living, and quality of life result directly from memory impairment (Arkin, Rose, & Hopper, 2000; Lubinski, 1991). Researchers attempting remediation of memory impairment in dementia often distinguish between explicit (declarative) and implicit (nondeclarative) memory. Explicit memory systems rely on conscious or intentional recall of past information or experiences. An individual's ability to remember specific events or facts, such as dates (e.g., appointments, anniversaries) is an example of explicit memory. Explicit memory is most affected in individuals with AD (Arkin, Rose, & Hopper, 2000). Implicit memory is mediated by unconscious retrieval of past experiences through habit or procedure (e.g., walk, talk, swallow, or read) and is preserved for longer periods of time in persons with AD. Bayles and Tomoeda (1996) propose several principles for improving communicative function in persons with dementia. First, demands on explicit memory systems should be reduced. Second, reliance on implicit memory systems should be increased. Third, activities that strengthen lexical and conceptual associations should be provided, and fourth, therapeutic activities should be familiar and meaningful to the person with dementia. Van Halle, Van der Linden, Bellville, and Gilbert (1998) state implicit memory is used in treatment when repeated exposure to stimuli improves patient performance with little conscious effort.

There are several different behavioral approaches available for the treatment of memory-related communication impairments in persons with AD. These treatments can be used separately or in combination depending on the severity of the client and his or her personal needs. Memory aids such as picture notebooks and wallets can help the client function more independently and increase communication (Bourgeois, 1994). Reality orientation therapy (ROT) is a psychosocial approach that employs formal or informal classes that reorient the client by means of continuous stimulation with repetitive orientation to the environment (e.g., location, date, names, personal information; Zanetti, Frisoni, De Leo, Dello Buono, Bianchetti, & Trabucchi, 1995). Montessori-based activities use philosophies from child Montessori programs and adapt them for elderly adults. Activities such as category sorting and games are used to stimulate language, increase active engagement in the environment, and decrease purposeless behaviors (Brush & Camp, 1999). Spaced retrieval training (SRT) is an intervention that gives individuals practice at successfully recalling information over progressively longer intervals of time (Brush & Camp, 1998).

SRT is a behavioral intervention that adheres to the above-mentioned principles. It is a method of learning and retaining information by recalling that information over increasingly longer periods of time. When retrieval is successful, the interval preceding the next recall test is increased. If recall failure occurs, the participant is told the correct response and asked to repeat it. Intervals, therefore, are manipulated to facilitate production of a high number of correct responses (or correct utilization of procedures) to the stimulus question and retention of information over increasingly longer periods of time (Brush & Camp, 1998). Strength of association between concepts in semantic memory depends on how often they are activated. Thus, repeatedly bringing into consciousness these associations will result in their increased accessibility (Brush & Camp, 1999). SRT, therefore, involves strengthening of associations, increasing reliance on implicit memory expression, and reducing demands on episodic and working memory (explicit memory).