Luijpen_2003_Rev.Neurosci_14_343

The present paper reviews studies examining the effects of non-pharmacological stimulation, i.e. bright light, physical activity and tactile stimulation (touch), on cognition, affective behaviour, and the sleep-wake rhythm of impaired and demented elderly, both in a qualitative (narrative) and quantitative (meta-analytic) manner. An extensive search through eight bibliographic data bases (PubMed, Web of Science, ERIC, PsychINFO, Psyndex, Cinahl, Biological Abstracts and Rehabdata) was performed up to August 2002. The primary criterion for inclusion in this review was that studies provided sufficient data to calculate effect-sizes. In the qualitative analysis, all three types of stimulation appeared to improve cognitive functioning. Disturbances in behaviour react positively to bright light and tactile stimulation. Bright light was also beneficial to sleep. Tactile stimulation had, moreover, a beneficial influence on the patient-caretaker relationship. A comparison was made with several representative papers published since 1991 on the effects of acetylcholinesterase inhibitors on cognition and behaviour with representative papers on non-pharmacological stimulation interventions. Data indicated that improvements in cognition and affective behaviour by non-pharmacological interventions (d' = 0.32) and by cholinesterase inhibitors (d' = 0.31) were of similar effect-size. Possible mechanisms underlying the non-pharmacological stimulation effects are discussed and suggestions offered for future research.