The Relationship Between Two Types of Artificial Lighting and Restlessness as Manifested by Level of Activation and Motor Activity in the Elderly

Abstract

The researcher's purpose in this study was to investigate a proposed relationship between the spectral power distribution of two different fluorescent lights and two measures of restlessness, motor activity and level of activation. Motor activity was measured using Down's and Fitzpatrick's (1926) Motor Activity Rating Scale. Level of activation was measured using Hoskins (1978) alternate forms of Thayer's Activation-Deactivation Adjective Check List.

The spectral power distribution of fluorescent lights was selected as a stimulus which might induce restlessness because different colors are known to have different arousing potentials. A General Electric Chroma 50 lamp provided broad spectrum fluorescent lighting. This light has a spectral power distribution which includes the cooler region of the spectrum. A General Electric SPX30 lamp provided warm white fluorescent lighting. This light has a spectral power distribution peaking toward the warm end of the spectrum. It was hypothesized that subjects' would demonstrate less motor activity under broad spectrum as opposed to warm white fluorescent lights. It was also hypothesized that subjects' level of activation would be less under broad spectrum as opposed to warm white fluorescent light.

Participants were men and women between the ages of 65 and 75 years who were homogeneous on factors known to influence level of activation and motor activity. A randomized block design was used in which each participant was exposed to each lighting condition for a period of twenty minutes in a lab setting. Measures of level of activation were taken at the ten and fifteen minute periods under each condition. The researcher and her assistant independently measured motor activity for five, two minute periods under each lighting condition.

A correlated t-test was run on the mean of the high activation factor under the warm white and broad spectrum fluorescent lights. A correlated t-test was run on the body movement intensity score under both warm white and broad spectrum fluorescent lights. No statistically significant difference in motor activity or level of activation was noted under either light. Subjects did indicate a preference for the broad spectrum light.