The Effects of Group Therapeutic Singing on Cortisol and Motor Symptoms in Persons With Parkinson's

The inclusion of music into the treatment plan for persons with Parkinson's disease (PD) may be a viable strategy to target multiple motor symptoms. However, potential mechanisms to explain why music has an impact on multiple motor symptoms in persons with PD remain understudied. The purpose of this study was to examine the acute effects of 1 h of group therapeutic singing (GTS) on physiological measures of stress and clinical motor symptoms in persons with PD. We posit that improvement in motor symptoms after GTS may be related to stress reduction. Seventeen participants with PD completed 1 h of GTS and eight participants completed 1 h of a quiet reading (control session). Cortisol was collected via passive drool immediately before and after the singing and control session. The Unified Parkinson's Disease Rating Scale (UPDRS) Part-III (motor examination) was also video-recorded immediately before and after the singing and control session and scored by two raters masked to time and condition. Secondary outcome measures for quality of life, depression, and mood were collected. Results revealed no significant change in cortisol or motor UPDRS scores, as well as no significant relationship between cortisol and motor UPDRS scores. There was a trend for the singing group to report feeling less sad compared to the control group after the 1-h session (effect size = 0.86), and heart rate increased in the singing group while heart rate decreased in the control group after the 1-h session. These results suggest that an acute session of GTS is not unduly stressful and promotes the use of GTS for persons with PD. Multiple mechanisms may underlie the benefits of GTS for persons with PD. Further exploring potential mechanisms by which singing improves motor symptoms in persons with PD will provide greater insight on the therapeutic use of music for persons with PD.


Over the next 20 years, the prevalence of Parkinson's disease (PD) is likely to double. Yet, there is no cure. Current predominant forms of treatment (i.e., drug therapy and deep brain stimulation) provide substantial relief but have significant side effects and are expensive (Borgohain et al., 2012; Borovac, 2016), and many symptoms of PD are not fully ameliorated by current treatments. Thus, there is a pressing need to develop therapeutic strategies that limit side effects, reduce treatment costs, and target multiple symptoms of PD.

Dance and music have been incorporated into current treatment strategies for PD. Learning and performing ballroom dance steps improved functional mobility, gait, and postural stability (Hackney and Earhart, 2009, 2010; Foster et al., 2013). Ballet and Irish dancing have resulted in acute improvements in functional mobility and postural instability (Houston and McGill, 2013; Volpe et al., 2013). Drumming has been shown to improve walking rate in persons with PD (Pantelyat et al., 2016). Our group has shown that group therapeutic singing (GTS) improved respiratory control, swallow, and quality of life (Stegemöller et al., 2016, 2017a). The singing groups were enjoyable for participants as they offered a way to relieve stress and have fun (Stegemöller et al., 2017b). Participants also viewed the groups as an avenue to express their concerns about having PD and build camaraderie with other people with PD (Stegemöller et al., 2017b). Taken together, this suggests that the inclusion of music into the treatment plan for persons with PD may be a viable strategy to target multiple motor symptoms as well as improve mood and quality of life.

Building on evidence showing promising outcomes, the next step is to uncover potential mechanisms to explain why music has an impact on multiple motor symptoms in persons with PD. The positive benefits of dance and drumming in PD may be related to increased physical activity as prior studies have shown that participation is associated with improvements in balance, gait, risk for falls, physical function, sleep cognition, and quality of life (Feng et al., 2020). However, it remains challenging to isolate the benefits of music vs. physical activity. GTS does not require an overt amount of physical activity, yet various motor symptoms and quality of life are improved. Further exploring the mechanism by which singing improves motor symptoms in persons with PD will provide greater insight on the therapeutic effects of music alone.

Building from our previous research revealing that participants with PD reported feeling less stressed after group therapeutic singing (Stegemöller et al., 2017b) and research that demonstrated music and singing can reduce perceived stress and reduce cortisol in various clinical populations (Miluk-Kolasa et al., 1994; Scheufele, 2000; Khalaf et al., 2003; Fukui and Toyoshima, 2008; Bradt et al., 2014; Fancourt et al., 2016), we posit that the improvement in motor symptoms may be due to reduced stress. When persons with PD experience stress, their motor symptoms frequently worsen (van der Heide et al., 2021). Indeed, when clinically evaluating tremor, patients are often given a mild cognitive stressor (i.e., count backwards by three) to trigger the emergence of tremor. To our knowledge, no study has examined the effects of singing on stress (or stress reduction) in persons with PD. The purpose of this study is to determine the acute effects of group therapeutic singing on clinical motor symptoms and stress. We hypothesized that after 1 h of singing, (1) clinical motor scores would improve, (2) cortisol, a biomarker of stress, would decrease, and (3) there would be a relationship between improved clinical motor scores and cortisol.


Twenty-five participants were enrolled into the study. Inclusion criteria included age between 40 and 85, a diagnosis of PD, and on the same PD medication for the past 30 days. Exclusion criteria included a score <24 on the Mini Mental State Exam. Demographic. Disease information at the day of study enrollment is shown in Table 1. All participants were tested on their optimal PD medication, following their regular timing and dosage, as prescribed by their treating physician. Time since last PD medication is shown in Table 1. All participants gave written informed consent prior to inclusion in the study, and the Institutional Review Board of Iowa State University approved the procedures. Participants were recruited from ongoing GTS groups in surrounding areas as well as from a general listserve of persons with PD interested in research. Participants currently participating in a GTS group were assigned to the singing intervention group. Those participant not currently participating in a GTS group were assigned to the control group. This resulted in 17 participants enrolled in the singing session, and eight participants enrolled in the control session.

Singing group.
Photo of a singing group. Photo by Robert Kneschke.

Singing Session

Seventeen participants completed 1 h of GTS. The singing session began with a greeting song lasting ~5 min. A series of vocal exercises lasting ~15 min followed the greeting song and included diaphragmatic breathing exercises, lip buzzing, glissandos, and articulation exercises. The vocal exercises have been used in previous group therapeutic singing studies.11−13 Specific songs targeting pitch range, articulation, and breath support followed the vocal exercises for ~15 min. Participants were then asked to choose songs they would like to sing for ~20 min. The session concluded with a closing song lasting ~5 min. Participants completed all songs and vocal exercises without written music or lyrics. A review of lyrics was provided as needed prior to singing each song. Participants were instructed to sit with appropriate posture, breathe from the diaphragm, lift the palate, and show facial expression while singing. A piano was used to accompany the vocal exercises and songs. The session was led by a board certified music therapist with over 15 years' experience leading therapeutic singing groups for persons with PD.

Control Session

Eight participants completed 1 h of a control (i.e., no singing) session. Participants were instructed to sit in a quiet room together and read quietly for 1 h. The room was in the same building where the singing sessions were held.

Data Collection

Data collection for both groups were completed using the same location. Prior to completing the singing or control session, participants completed a series of questionnaires. The Parkinson's Disease Questionnaire (PDQ-39) was collected as a measure of quality of life and the Beck Depression Index (BDI) was collected as a measure of depression (Jenkinson et al., 1997; Goodarzi et al., 2016). The total Unified Parkinson's Disease Rating Scale (MDS-UPDRS) was collected as a measure of disease severity (Martinez-Martin et al., 2013). Number of years singing in the therapeutic singing group was also collected (Table 1). In addition, a daily diary was completed documenting food intake, exercise, tobacco use, and unusual events for 24 h prior to data collection. The daily diary also included a subjective report of anxiety, anger, happiness, and sadness on a scale from 1 to 7. This scale was completed prior to and after the singing or control session and served as secondary outcome measures for further exploratory analyses (Table 2). Resting heart rate and blood pressure collected pre and post-session are shown in Table 2.

Unified Parkinson's Disease Rating Scale

The motor MDS-UPDRS was used as the primary outcome measure for clinical motor symptoms. The scale was administered by a trained rater immediately before and after the singing session. Video recordings were