Key to maintaining a satisfactory level of physical and mental health in the face of unavoidable decline characteristic of ADRD is independently taking in adequate amounts of food during mealtimes. Volkert and co-authors (2018) emphasize that “Nutrition is an important modulator of health and well-being in older adults” (p. 2). Those with ADRD are at greater risk for malnutrition, with risk factors that include “the older person’s social, economic and environmental situations; problems with mouth, teeth and swallowing; mental, neurological and other chronic physical diseases; and side effects of long-term treatment with certain drugs” (Prince et al., 2014, p. 6). Other factors include compromised taste sense, impaired planning (i.e., executive function), loss of interest in food, and lack of attention to the eating process (Brooke & Ojo, 2015; Suma et al., 2018). Anxiety and depression, which are common among persons with ADRD, are also related to poor nutritional intake (Amella et al., 2008). Malnutrition can result in frailty, reduced mobility, increased risk of falls and fractures, serious health conditions, and increased mortality (Prince et al., 2014). Evidence-based environmental and nonpharmacological interventions thought to maximize the potential for adequate food intake, including music in some form, have received considerable attention in the literature.

A recent systematic review of music-based interventions for persons with dementia provides the most up-to-date information about the potential impact of music in dementia care (van der Steen et al., 2018). The researchers analyzed 22 studies; unfortunately, neither malnutrition nor problematic weight loss were identified outcome measures. However, in describing music’s impact, the authors wrote, “Music may also be used in ways which are less obviously therapy or therapeutic, for example, playing music during other activities, such as meals or baths…” (p. 6).

Multiple researchers have explored the use of recorded music as an environmental additive to ameliorate agitation and aggressive behaviors during mealtimes. Using adaptations of the Cohen-Mansfield Agitation Inventory (CMAI), they measured physical and verbal aggressive behavior and physical and verbal non-aggressive behavior. Findings are inconsistent, with one study (Ho et al., 2011) reporting a significant decrease in all four behaviors, one (Chang et al., 2010) pointing to a significant decrease in physical and verbal aggressive behavior (but no change in physical and verbal non-aggressive behavior), and one (Hicks-Moore, 2005) noting positive trends on all measures but no significant change. It should be noted that it was not these researchers’ intent to test the impact of music on nutritional intake; rather, the purpose was to identify whether recorded music played in the dining environment could mitigate challenges that adversely impact facility staff. Nonetheless, it seems reasonable to assert that a less chaotic or distracting environment, promoted when agitation is reduced, might also be conducive to more productive eating for residents with ADRD.

Authors noted the positive potential of background music in the dining environment as a nonpharmacological intervention for feeding difficulties of older adults with ADRD. In a study of older adults in Sweden, Ragneskog and colleagues (1996) found a 22% increase in length of time that residents spent in the dining room when various styles of music were played, with the longest time in response to “soothing” music and the second longest time with “popular Swedish” music. The researchers also reported positive changes during music interventions with regard to mood, agitation, and a decrease in the rate of speed at which residents ate their meals.

Richeson and Neill (2004) played recorded “relaxing” or “quiet” music in the dining area and evaluated agitation behaviors using the CMAI. Food intake was measured by calculating the difference between nursing staff estimates of percentage of food eaten during baseline and treatment phases. The researchers reported improvement in most of the agitation category scores and an 8.6% increase in estimated food intake.

Wong and colleagues (2008) used a multi-phase series of interventions to enhance nutritional intake of persons with ADRD who were admitted to a hospital assessment unit. The phases were baseline, encouragement of “dietary grazing,” extended staff assistance, and playing recorded “soothing” music. Researchers measured a variety of dietary concerns including each individual’s weight, body mass index, a malnutrition questionnaire, an Eating Behavior Scale, and a staff “plate waste measure” indicating the difference between the estimated amount of food served and the amount left after the meal (p. 310). Caloric intake at lunchtime was reported to have significantly increased during the music phase. Interestingly, overall food intake decreased with music played during breakfast, and patients remained in the dining area longer when music was present.

Thomas and Smith (2009) used a non-randomized, time-series crossover (ABAB) design to study the impact of background music to increase caloric intake. Twelve individuals served as their own controls. Food intake was measured using a visual estimation system of quartiles (i.e., 0%, 25%, 50%, 75%, 100%) of food consumed. Recorded music including popular classical compositions, traditional American, English, and Irish folk melodies, and 13th century English dance music was played in the dining area alternately for 8 weeks. Results showed an overall increase in caloric intake of 20% during weeks with music versus weeks with no music. Residents also stayed longer in the dining area when music was present, thereby enhancing the potential for continued eating and social interactions.

Leah’s (2016) systematic review of nonpharmacological interventions to enhance food intake included reviews of the Richeson and Neil (2004), Thomas and Smith (2009) and McHugh, et al. (2012) studies, and noted that only the receptive music experiences seemed to provide a positive influence on the volume of food intake. However, Leah had only McHugh et al’s pilot study for comparison of singing with listening. The impact of singing, therefore, seems an important yet underdeveloped area of research relative to food intake. Leah’s findings, therefore, serve as one impetus for the present research on an active versus receptive music intervention. A further motivation for this study is the general need for replication research in the music therapy literature as well as research on singular method variations (rather than on a variety of interventions typically facilitated during sessions), as called for in the proceedings of the AMTA sponsored symposium titled, Improving access and quality: Music therapy research 2025 (AMTA, 2015). The purpose of the present study was to investigate the impact of 30 minutes of singing engagement facilitated by an MT-BC on the subsequent volume of food intake during the midday meal for individuals with ADRD.

This study used a repeated-measures (within-subjects) experimental design with participants serving as their own controls to measure the effectiveness of group singing on volume of food intake during the midday meal. Participants’ food intake was measured three days per week at each of three sites for 4 weeks:

Much of the literature related to food intake of people with ADRD consistently advocates for a calm dining environment (Douglas & Lawrence, 2015; Prince et al., 2014; Suma et al., 2018; Volkert et al., 2018). In that auditory overstimulation and distractions were apparent during meals at all three sites (e.g., residents calling out in the dining area; loud conversations between staff, residents, and visitors; music “bleeding” in from adjacent rooms), it is possible that study participants experienced anxiety and confusion that contributed to changes in appetite and commensurate decreases in intake. That said, one might confidently dismiss this factor as related to study findings in that these sounds were not unique to either the treatment or baseline conditions; rather, the dining experience at all three sites was consistently characterized by stimuli of these types, frequencies, and intensities.

Certain intrapersonal attributes may cause variations in appetite and thus should be examined for potential explanatory power. These include the participants’ diagnostic profiles, food preferences, and physical states.

Pleasurable experiences have been shown to lead to the release of certain neurotransmitters including serotonin, which is produced in the nucleus accumbens (NAc) and hypothalamic regions of the brain (Chanda & Levitin, 2013; Mavridis, 2015; Menon & Levitin, 2005; Taylor, 1997). In fact, Mavridis referred to the nucleus accumbens as, “the most important pleasure center of the human brain (dominates the reward system)…” (2015, p. 121), and reported that “…reward value for music can be coded by activity levels in the NAc, whose functional connectivity with auditory and frontal areas increases as a function of increasing musical reward” (p. 121). Thus, engaging in inter-musical and inter-personal processes inherent in group singing with an MT-BC can be viewed as emotionally and socially rewarding on a neurological level (Altenmüller & Schlaug, 2013; Chanda & Levitin, 2013; Evers & Suhr, 2000; Mavridis, 2015). Altenmüller and Schlaug (2013) write,

In studying the “neural mechanisms underlying intensely pleasurable emotional responses to music,” Blood and Zatorre (2001) asked university students to listen to preferred and nonpreferred recorded musical selections (p. 11818). Positron emission tomography (PET) scans of brain activity revealed that pleasurable experiences of music were correlated with increased activity in the nucleus accumbens. Although these researchers did not specifically measure the presence and volume of serotonin, one might conjecture that increased activity in the nucleus accumbens may have triggered such production, as highlighted by Altenmüller and Schlaug (2013). In fact, Blood and Zatorre note that activity in the region of the nucleus accumbens is directly related to processes of neural reward and is “known to involve dopamine and opioid systems, as well as other neurotransmitters” (p. 11822).

In what seems to be a rigorously designed and executed trial, Evers and Suhr (2000) found a significant correlation between healthy adult participants’ perceptions of music listening experiences as either “pleasant” or “unpleasant,” and report an increase of blood platelet serotonin levels for both, with pleasant music yielding significantly higher levels compared to unpleasant music. Menon and Levitin (2005) used functional magnetic resonance imaging (fMRI) to examine connectivity between various brain structures involved in neurologic reward to music listening in adult non-musicians: the nucleus accumbens (NAc), the ventral tegmental area (VTA), and the hypothalamus. Participants listened to a random series of classical music segments in typical and “scrambled” forms in 24-second episodes. Results for the segments considered pleasant versus not pleasant (i.e., scrambled) showed significant activation of the structures in question with significant neural connectivity between them and with indication of a recognizable pattern of activation. As in the Blood and Zatorre (2001) study, Menon and Levitin did not measure the presence and volume of serotonin, yet it is plausible that release of serotonin would, in fact, occur due to stimulation of the NAc related to the experience of a pleasant, rewarding musical stimulus.

The relationship between musical engagement as a rewarding activity with concurrent serotonin production is relevant to the present discussion primarily because the function of serotonin as an appetite suppressant is well-documented in the scientific literature (Blundell & Halford, 1998; Wurtman & Wurtman, 1995, 2018). Liebowitz and Alexander (1998) reviewed research on the impact of hypothalamic serotonin on appetite. The authors explain that stimulation of serotonin receptors of the hypothalamus “…reduce food intake and weight gain and increase energy expenditure, both in animals and in humans” (p. 851). These authors also argue that pre-meal consumption of carbohydrates “…enhances the synthesis and release of hypothalamic 5-HT [serotonin], which in turn serves to control the size of carbohydrate-rich meals” (p. 851). Wurtman and Wurtman (1995, 2018) concur with the relationship between carbohydrates and serotonin release and support the notion that, regardless of the manner in which serotonin is produced, it is influential in regulating appetite and eating behavior.

It seems that as far back as 1998, the scientific evidence for the impact of serotonin as an appetite suppressant was considered conclusive. Blundell and Halford’s (1998) review of 20 years of research on drugs designed to suppress appetite by either stimulating serotonin production or inhibiting serotonin reuptake reported unequivocally that, “A consistent pattern of reduction in hunger motivation and energy intake is seen in human studies with a variety of serotonergic agents” (p. 474). In fact, it is difficult to find current research designed to reinforce or refute this now established relationship, and researchers have moved on to focus on clinical applications of serotonin’s role in health concerns such as depression, suicidality, and obesity (Wurtman & Wurtman, 2018).

In that music engagement stimulates serotonin production and serotonin suppresses appetite, it is possible that study participants at sites 1 and 3 experienced these effects—that is, adequate stimulation of serotonin by engaging in pleasurable music experiences resulted in diminished appetite during the subsequent meal, thereby explaining the lower average food intake during treatment weeks.

Unlike participants at Sites 1 and 3, mean food intake on singing days for participants at Site 2 was greater than baseline days, indicating potentially less serotonin release for these individuals. Two interrelated explanatory factors are most relevant: the environment and the MT-BCs who provided singing engagement. First, compared to the treatment environments at Sites 1 and 3 (and as noted in Table 2 above), the dining tables at which Site 2 participants sat were widely dispersed in the multi-purpose room. The MT-BCs reported that this made it difficult to effectively use close proximity as a technique for enhancing engagement and promoting relationship. Secondly, Site 2 was the only location wherein three different MT-BCs provided singing engagement during treatment days. This unavoidable variation in facilitators may also have adversely affected the potential for therapeutic relationship to develop between the participants and facilitators, even on the very basic level of participants experiencing familiarity with the MT-BCs’ physical appearance. It may be the case, therefore, that the musical experiences for Site 2 participants on treatment days were insufficient for stimulating serotonin production with commensurate limited change in food intake status versus baseline days.

Lastly, results showed that participants at Site 3 consumed, on average, more grams of food and beverage than those at Site 1; the difference amounted to approximately 89 grams. Differences in the environment and meal processes between Sites 1 and 3 might account for Site 3 participants’ more productive eating. For example, from the PI’s perspective, the environment of Site 1 was considerably more stimulating than Site 3 in terms of the sheer volume and variety of sounds from various sources as well as a higher level of physical activity occurring in and around the dining space by non-participant residents and staff. This was largely due to the fact that participants at Site 1 were not isolated in their own memory support unit, as were the Site 3 participants, but rather lived on a floor of the facility among many other residents who shared the space. With regard to meal processes, residents at Site 3 were consistently offered a choice of entrée, carried out by staff presenting two different plates of food for the participants to see, ask questions about, and thereby choose their meal. Thus, it might simply be the case that having a choice in the dining moment based on seeing and, perhaps, smelling the food stimulated appetite, more productive eating, and therefore greater average intake.

Given the varied environments encountered and the fairly small sample size in this study, generalization of the findings must be considered carefully. Whereas great care was exercised with regard to song choices and stylistic preparation, differences between the appearance, vocal timbre, and interpersonal approaches of the three music therapists may have differentially impacted the way the residents perceived and engaged in the singing process, and therefore their later behavior during mealtime. Consistency of a single therapist, with the related potential for developing and sustaining stronger relationships with the residents, may induce different results.

Assuming the potential adverse relationship between enjoyable music engagement that stimulates serotonin production and the proven appetite suppression characteristics of serotonin, it seems prudent to recommend, although cautiously, that care be exercised regarding the timing of active music engagement and mealtimes for persons with dementia whose health status may include nutritional complications. How long it takes for the serotonin production and metabolism that may occur due to enjoyable music engagement is unknown. In fact, questions regarding typical processing of serotonin remain as they are multifaceted and require complex mathematical formulas that are still under investigation and development (Best et al., 2010). Given that serotonergic processes are constantly occurring in the brain, and without evidence to the contrary, 30­ to 60 minutes between active music engagement and the start of a meal seems a reasonable recommendation. Whereas this recommendation may appear problematic or inconvenient for music therapists, it is nonetheless important to consider that music has both the potential for promoting health and well-being, but also to cause harm or detrimental effects (Gardstrom, 2008; Hiller & Gardstrom, 2019). Careful attention to scheduling of music therapy sessions for individuals with dementia and nutritional challenges may ameliorate concerns in this regard.

The intent of the present study was to discern whether or not singing would stimulate food intake. It must be noted, however, that participants’ musical involvement varied: Not all participants vocalized, in spite of the MT-BC’s consistent use of techniques of engagement that have been documented in the literature as useful and effective in the treatment of older adults with dementia (e.g., use of participants’ names, proximity, and alterations to musical elements and form; Cevasco, 2010; McHugh et al., 2012; Young, 2013). While certain individuals in the groups were prone to fairly consistent singing or inaudible mouthing of the words in “real time,” others sang or mouthed words only sporadically during the sessions. On average, across all sites, approximately one third of participants fit into these two categories. The balance of participants engaged more as listeners—watching the MT-BC as she moved about the space, tapping their feet or hands, and smiling in response to certain songs and verbal comments. The implication of these observations is that findings might be interpreted as applying not only to the experience of active engagement through singing but also to the experience of active engagement through listening. Researchers might consider tracking individual participants’ level of engagement during music-based treatment episodes through videotape or observations of trained observers; this could identify relationships between an individual’s level of musical engagement and subsequent manifestations of symptomology or healthy sorts of responses. Future researchers may also wish to address the concept of engagement—what it feels like for a participant and what it looks like for an observer—and factors that may be involved at different levels of engagement. Interpretivist (i.e., qualitative) research may bring light to the feeling-full and motivational nature of singing engagement for both residents and therapists as well as ground theorizing in the phenomenon of singing engagement with others. Lastly, future researchers might benefit from tracking the specific dementia diagnoses of participants, as differential symptomology surrounding the various types have a bearing on dietary needs and eating habits.