The Effect of Dopaminergic Medication on Beat-Based Auditory Timing in Parkinson’s Disease

Abstract

Parkinson’s disease (PD) adversely affects timing abilities. Beat-based timing is a mechanism that times events relative to a regular interval, such as the “beat” in musical rhythm, and is impaired in PD. It is unknown if dopaminergic medication influences beat-based timing in PD. Here, we tested beat-based timing over two sessions in participants with PD (OFF then ON dopaminergic medication) and in unmedicated control participants. People with PD and control participants completed two tasks. The first was a discrimination task in which participants compared two rhythms and determined whether they were the same or different. Rhythms either had a beat structure (metric simple rhythms) or did not (metric complex rhythms), as in previous studies. Discrimination accuracy was analyzed to test for the effects of beat structure, as well as differences between participants with PD and controls, and effects of medication (PD group only). The second task was the Beat Alignment Test (BAT), in which participants listened to music with regular tones superimposed, and responded as to whether the tones were “ON” or “OFF” the beat of the music. Accuracy was analyzed to test for differences between participants with PD and controls, and for an effect of medication in patients. Both patients and controls discriminated metric simple rhythms better than metric complex rhythms. Controls also improved at the discrimination task in the second vs. first session, whereas people with PD did not. For participants with PD, the difference in performance between metric simple and metric complex rhythms was greater (sensitivity to changes in simple rhythms increased and sensitivity to changes in complex rhythms decreased) when ON vs. OFF medication. Performance also worsened with disease severity. For the BAT, no group differences or effects of medication were found. Overall, these findings suggest that timing is impaired in PD, and that dopaminergic medication influences beat-based and non-beat-based timing differently. Judging the beat in music does not appear to be affected by PD or by dopaminergic medication.

Abnormal phasic activity in saliency network, motor areas, and basal ganglia in Parkinson's disease during rhythm perception

“…If the processing of more complex rhythms is more dependent on recruiting frontal areas (Chapin et al, ; Kung et al, ), an overall more complex signal in the PD‐group could also explain the increased activity in the left‐PFC in the PD‐group. Hyperactivity in PT, IPL, and left‐PFC in the PD group could therefore be due to dysfunction in the basal ganglia, with rhythms being processed by the PD‐group as if they were perceived as overall more complex than by the healthy subjects, a finding that is consistent with the results of our online listening test and previous behavioral studies on PD (Biswas et al, ; Cameron et al, ; Grahn & Brett, ).…”

“…Studies on rhythm perception in PD have found discrimination deficits, that is, difficulties in judging, when subsequent rhythms are identical or different. Some studies find this deficit to be more pronounced for simpler rhythms (Biswas, Hegde, Jhunjhunwala, & Pal, ; Grahn & Brett, ), while one study shows a more generalized deficit (Cameron, Pickett, Earhart, & Grahn, ). The effect of dopamine replacement therapies on rhythm perception indicates that medication improves beat detection in simple rhythms (Cameron et al, ; Geiser & Kaelin‐Lang, ), but has adverse effects on more complex rhythms (Cameron et al, ).…”

“…Some studies find this deficit to be more pronounced for simpler rhythms (Biswas, Hegde, Jhunjhunwala, & Pal, ; Grahn & Brett, ), while one study shows a more generalized deficit (Cameron, Pickett, Earhart, & Grahn, ). The effect of dopamine replacement therapies on rhythm perception indicates that medication improves beat detection in simple rhythms (Cameron et al, ; Geiser & Kaelin‐Lang, ), but has adverse effects on more complex rhythms (Cameron et al, ). Rhythm and rhythmic complexity modulate neural activity in areas and widespread networks across the brain and imaging studies in PD show abnormal activity in many of these areas, some of which are directly related to the pathology of PD.…”

“…), while one study shows a more generalized deficit (Cameron, Pickett, Earhart, & Grahn, 2016). The effect of dopamine replacement therapies on rhythm perception indicates that medication improves beat detection in simple rhythms (Cameron et al, 2016;Geiser & Kaelin-Lang, 2011), but has adverse effects on more complex rhythms (Cameron et al, 2016).…”

The feasibility of singing to improve gait in Parkinson disease

“…Ability to do the task was likely not attributable to musical experience, as only nine participants reported having any musical training. In addition, our participants were a subset of a larger sample that showed impaired beat processing as compared to controls [26], confirming past reports among people with PD [27]. Our results support the idea that, in spite of this deficiency, people with PD can internally generate music and use it as a cue to guide movement, as was shown previously in a study in which imagined singing was used to improve motor timing in people with PD [13].…”