Psychobiological mechanisms underlying the health-beneficial effects of music in people living with dementia : A systematic review of the literature

Abstract

Background: Music has been used as agent in medicine for decades. The applications of music in health span from music therapy to music listening interventions to mere music listening. Music may reduce stress and improve health in people living with dementia (PwD), but the exact underpinnings of these effects are unclear. It is proposed that beneficial effects of music are mediated by a reduction in psychobiological stress. Therefore, the present review aims to shed light on the potential psychobiological mechanisms underlying the health-beneficial effects of music in PwD. Methods: We searched for studies investigating health-beneficial effects of music in PwD by means of psychobiological stress measures using the PubMed, PsycINFO and Web of Science databases and by hand-searching. Results: The inclusion criteria were met by 12 studies. Seven of the included studies investigated effects of music therapy on the autonomic nervous system (ANS), the hypothalamic-pituitary-adrenal (HPA) axis or the immune system in patients with mild to moderate dementia. Results showed decreased ANS activity as measured by heart rate variability but no effect on alpha-amylase. Effects on blood pressure were mixed. Concerning the secretion of cortisol, one study found decreased HPA axis activity whereas two studies found no significant effects. No effects were found on salivary immunoglobin A. Three studies investigated the effects of music listening interventions in patients with severe dementia by means of predominantly ANS parameters with evidence indicating increased parasympathetic activation after music listening. Two studies investigated the effects of mere music listening on skin conductance using experimental designs. One study found increases in arousal due to music listening, whereas the other study found no effect. Discussion and Conclusion: These very preliminary results indicate effects of music on central stress pathways in PwD, but also highlight the need for further research focussing on a comprehensive assessment of autonomic, endocrine and immunological parameters in response to music. Furthermore, future studies should directly compare music therapy to music listening interventions and mere music listening in samples of PwD of varying disease severity and varying care settings.