Insufficient inclusions in the available time after an extension of 50% with the sample at 16/20.

The goal of this longitudinal, single-subject study is to investigate the role of motivation in music therapy for stroke patients within the subacute phase, who experience upper limb and/or attention deficits. The main questions it aims to answer are:

• Does music therapy increase patient's motivation to rehabilitate?
• Do increases in motivation correlate with functional improvements, in particular upper limb and/or attention skills?

Participants will receive up to 9 music therapy sessions within 3-5 weeks, with functional assessments before and after each period. Each participant serves as their own comparison: researchers will compare a period with standard care only (control phase) to a period with music therapy plus standard care (intervention phase), the order of which will be randomized in advance.

Rationale: Stroke is a highly disabling condition, for which music therapy is regularly used in rehabilitation. Motivation is considered to be a mechanism for functional improvements, including in neurologic music therapy (NMT), likely due to potential mood improvements, but it is not generally explicitly investigated. This motivation level may in turn affect not only functional outcomes and subjective well-being, but also adherence to other rehabilitation therapies.

Objectives: The primary goal of the study is to investigate motivation as an underlying mechanism of neurologic music therapy (NMT) for stroke patients experiencing upper-limb impairments and/or cognitive deficits, in the sub-acute phase of stroke. A secondary goal is to assess NMT-related changes in motor function, cognitive outcomes, and self-reported measures of well-being.

The hypothesis is that NMT will increase motivation, and that increased motivational state will positively affect functioning in both motor and/or cognitive domains.

Study design: The study has a longitudinal, single-subject design; as stroke patients are not a homogenous group, this design is adopted to control for expected within-subject variations. To account for variability in brain damage that is caused by stroke, each subject thus serves as their own control, and a longitudinal, repeated-measures design is selected. Participants will be randomized into two groups for a cross-over design, either receiving the intervention or the control phase first or vice versa, which counters order effects and assesses intervention effectiveness (as part of the secondary goals).

All subjects will receive NMT targeting both upper- limb movement and attention. All participants will receive a target of 9 NMT sessions (participants who complete a minimum of 6 sessions will be included in the analysis) over 3-6 weeks (depending on the rehabilitation trajectory, as subacute patients generally are admitted for a minimum of ± 6 and a maximum of 16 weeks), aiming for an average of 3 sessions per week, but adjusted to a patient's expected length of stay and ability, using a tailored approach.

Participants will receive three measurements. A baseline measure (TP1), on the first week of the rehabilitation trajectory, a second measure (TP2) either after the treatment/intervention period or control/ care as usual period (depending on the randomisation) and a post-treatment (TP3). The time interval between TP1- TP2 and TP2-TP3 are at least 21 days (3 weeks), with a margin of maximum 4-7 days, depending on their expected length of stay in the care facility.

Study population: In order to be eligible to participate in the study, a participant should be above 18 years of age and have had their first-ever supratentorial stroke between 2 weeks and up to 6 months before enrollment. Moreover, participants will have a referral for a paretic upper limb, i.e., partial loss of the capacity to carry out a voluntary upper limb movement and/or difficulty with attention/concentration, (e.g., complaints of being easily distractible, or unable to focus on a specific task in the presence of competing information, or complain of decline in attention). Participants must be able to receive music therapy for a minimum of 2-3 sessions per week, aiming for a total of 9 sessions over a minimum of three weeks, reducing this to 6 sessions in 2 weeks if required. The frequency of sessions is based on their ability and expected length of stay. Good command of the Dutch or English language is also a prerequisite for participation.

Participants will be excluded if this is not their first stroke or if a second stroke occurs during their stay. Further exclusion criteria are the following: i) upper limb paralysis as assessed by a score < 2 points on the Medical Research Scale (MRC) for muscle strength; ii) severe behavioural and/or cognitive problems preventing understanding or carrying out instructions or risk of dementia (a score <21 on the Mini-mental state examination; MMSE); iii) severe communication problems, e.g., severe aphasia and/or apraxia of speech; iv) known psychiatric, substance abuse, or neurological comorbidity. For participants who score <24 on the MMSE, a follow-up check will be carried out for a possible dementia diagnosis which would retrospectively lead to exclusion.

Sample size: In a previous study, 40 stroke patients in the sub-acute phase were allocated to either twenty 30-minute sessions of music-supported therapy (N = 20; 4 withdrew/excluded; 16 in final analysis) or twenty additional sessions of conventional therapy (N = 20; 2 withdrew/excluded; 18 in final analysis). The study found a significant correlation (r = .562, p = .024) between patients' intrinsic motivation to engage in musical activities as measured by the BMRQ at baseline and improvement of upper-limb function as measured by the Action Research Arm Test (ARAT) at 3 months, which was not found in the comparator of occupational/physical therapy (r = -.305, p < .21), with a significant difference between correlations (z = 2.4, p < .05). Using G power 3 analysis, the investigators estimated that 18 participants are needed to observe a similar effect size for a sufficiently powered study (α=0.05 and (1-β)=0.8; ρ H1 = 0.56). This indicates that 20 participants completing the entire protocol would be required to observe an effect of motivation in music therapy, with an expected attrition/missing data rate of 10-20%. This sample size is similar to the number of participants used in studies showing an effect for our secondary objectives, ranging from 14-20 participants, on the effects of music therapy on motor function, cognition, and psychological wellbeing. Recruitment will continue until 20 participants have completed the protocol.

Intervention: The intervention condition will consist of a target of up to 9 sessions in total, administered over an average of 5 weeks, but may span from 2 to 8 weeks according to the patient's length of stay at the Leo Polak Stroke Rehabilitation Centre. All music therapy interventions will be delivered by a registered music therapist. The protocol aims for participants to receive a minimum of two sessions per week over the duration of the study enrollment. However, this schedule may not be possible in every case due to the participants' length of stay. Participants who complete a minimum of 6 sessions will be included in the final analyses. The number of sessions each participant receives will be recorded and treated as a variable systematically recorded, and the number of sessions will be accounted for in the statistical analysis.

Main parameters/ endpoints: The main parameters of the study focus on the differences in motivation levels of participants as the result of applying NMT techniques in the subacute phase of stroke, comparing within-subject differences between changes related to the intervention and the control period. The motivation level of participants will be measured using the BMQ-S [patient-rated] as state-level motivation. The secondary parameters relate to behavioural outcomes of upper limb, and cognitive functions, as well as self-reported measures of well-being following NMT for within-participant comparisons between the intervention and control period.

Inclusion Criteria:

• Subjects had their first-ever supratentorial stroke between 2 weeks and up to 6 months before enrolment
• Paretic upper limb and/or attention/ concentration problems
• Ability to communicate in Dutch or English

Exclusion Criteria:

• Severe (global) aphasia
• paralysis of upper limb
• severe cognitive decline (MMSE <24)

To the extent that participants give permission to share their data, Data relating to the main outcomes will be shared in online repository. Coded data will be published in an online scientific archive for the purpose of future research, in line with Open Science practices, and for the verification of findings for 10 years according to the Data Management Guidelines of the Health, Medical, and Neuropsychology Unit (v171220), Institute of Psychology, Faculty of Social and Behavioural Sciences at Leiden University. These data would not be traceable as they are not linked in any way to personal data.

Coded data will be published in online scientific archive without a time limit, all participant data, including physical documents will be archived at Faculty of Social and Behavioural Sciences at Leiden university for 10 years.

Coded data that cannot be traceable to the participant identifying information will be published in an online repository, the web address of the repository will be included for each publication that results from the study. No restriction to access the publicly available data will be imposed, however, future studies that use the data of the study will be required to make reference to the study AND/OR the repository.

Analyses will be done after blinding to participant id and gender.