Finding the Pill on the Floor: How Contrast Sensitivity Affects Daily Living Skills in Alzheimer’s Disease Patients

Undergraduate Review Volume 6 Article 12 2010 Finding the Pill on the Floor: How Contrast Sensitivity Affects Daily Living Skills in Alzheimer’s Disease Patients Marlyn Colon Follow this and additional works at: http://vc.bridgew.edu/undergrad_rev Part of the Nervous System Diseases Commons, and the Psychology Commons Recommended Citation Colon, Marlyn (2010). Finding the Pill on the Floor: How Contrast Sensitivity Affects Daily Living Skills in Alzheimer’s Disease Patients. Undergraduate Review, 6, 55-59. Available at: http://vc.bridgew.edu/undergrad_rev/vol6/iss1/12 This item is available as part of Virtual Commons, the open-access institutional repository of Bridgewater State University, Bridgewater, Massachusetts. Copyright © 2010 Marlyn Colon Finding the Pill on the Floor: How Contrast Sensitivity Affects Daily Living Skills in Alzheimer’s Disease Patients MARLYN COLON Marlyn is a senior majoring in Psychology, graduating in May of 2010. This research began as a project funded by the Adrian Tinsley Program at Bridgewater State College in the summer of 2009, under the mentorship of Dr. Sandra Neargarder. Marlyn has presented her research at BSC’s Summer Symposium as well as Cognitive Aging Conference in Atlanta, GA. This experience helped her finalize plans for the future. After graduation, she plans to work as a research assistant and pursue a PhD in A lzheimer’s disease (AD) is a progressive brain disorder that gradually destroys an individual’s mental functioning and social capabilities, including the ability to carry out everyday activities. Although memory deficits affect AD patients’ ability to perform these activities, research suggests that visual perception impairments also contribute. One impaired visual perception ability, contrast sensitivity, enables one to distinguish an object from its immediate surroundings. The present project measured contrast sensitivity in a real-world task by having AD patients find a pill of various shades of gray on a tiled background. Results were compared to young and elderly control participants. Participants also filled out a questionnaire examining activities of daily living (ADLs). Results demonstrated that impairments in contrast sensitivity were observed both as a function of normal aging and as a result of AD. Performance correlated with the ADLs of household care and travel for both groups. Increasing contrast in environmental settings may aid these individuals, especially AD patients, in living a more independent lifestyle. Research Question How does the manipulation of contrast affect Alzheimer’s disease patients’ ability to detect a pill on a white-tiled surface? Do these findings relate to problems in activities of daily living experienced by these patients? Clinical Neuropsychology. Introduction General Introduction. Alzheimer’s disease (AD) is a progressive brain disorder that gradually destroys an individual’s mental functioning and social capabilities, including memory, reasoning, decision-making, communication, and the ability to carry out everyday activities. According to the Alzheimer’s Association, AD affects approximately 4.5 million Americans annually. By the year 2050, this number is expected to increase to 11.3 to 16 million. Although memory deficits are a primary symptom of AD and the one most often researched, other abilities including those in visual perception are also impaired (Cronin-Golomb, A., 1995; Gilmore, G. C., Cronin-Golomb, A., Neargarder, S., & Morrison, S. R. 2005; Mendola, J. D., Cronin-Golomb, A., Corkin, S. & Growdon, J. H., 1995; Neargarder, S. 2005). One impaired ability known as contrast sensitivity has direct implications for the ability of AD patients to carry out everyday activities. Contrast sensitivity is defined as the smallest difference in intensity that a person can resolve between an object and its immediate surroundings. For example, what shade of gray would an BRIDGEWATER STATE COLLEGE 2010 • THE UNDERGRADUATE REVIEW • 55 electrical outlet need to be before a patient could detect it against a white wall? Research shows that deficits in contrast sensitivity directly affect everyday activities such as food and liquid intake (Dunne, Neargarder, Cipolloni, & Cronin-Golomb, 2004) object detection (Neargarder & Cronin-Golomb, 2005), and face discrimination (Cronin-Golomb, Cronin Golomb, Dunne, Brown, & Jain, 2000). Background. A number of research studies have identified contrast sensitivity impairments in AD patients (Cronin Golomb, Growden, & Corkin, 1995; Cronin-Golomb, Gilmore, Neargarder, Morrison, & Laudate, 2007). Results from these studies were obtained in a laboratory setting using a series of clinical vision charts such as the Vistech and the FACT (Functional Acuity Contrast Test). These tests allow one to measure contrast deficits across a range of different spatial frequencies. Results show that AD patients exhibit contrast deficits across all levels of spatial frequency. This would potentially make it difficult for patients to distinguish between people, places, and things in a real-world environment. Although research has demonstrated that deficits measured in a laboratory setting using vision charts relate to deficits in the real-world, we have no direct measure of contrast sensitivity in real-world tasks. For example, although we may know that patients will do better in a high-contrast task (pouring milk into a black mug) than a low-contrast task (pouring milk into a white mug), we do not know what the contrast between the two items (milk and cup) needs to be in order for the patient to succeed at this task. Present Project. The present project aimed to measure contrast sensitivity in a real-world task by having AD patients find pills of various shades of gray on a tiled background (simulating a white-tiled floor). This method allowed us to find the exact contrast the pill needs to be to the background in order for patients to be able to successfully find the pill. These findings were then compared to a questionnaire that measured general activities of daily living. This enabled us to compare laboratory based tests to everyday functioning. The results from this study aim to increase the functional independence of AD patients, both in the home environment and nursing home facilities. This increase in independence can result in reducing health care costs and increase the overall well-being of patients. Methodology Participants. This study consisted of 15 patients with AD, 13 healthy elderly control participants (EC) and 25 young participants (YC). EC participants were community volunteers and AD patients were recruited from Community Family Incorporated (AD day programs) located in Lowell and Medford, Massachusetts. Participants were matched on education, age, and near acuity. 56 • THE UNDERGRADUATE REVIEW • 2010 Materials and Procedures. Materials consisted of a questionnaire that measured activities of daily living, and four conditions that measured the abil (...truncated)