Two sides of the same coin: Impairment in perception of temporal components of rhythm and cognitive functions in Parkinson’s disease

Inhibitory control and working memory predict rhythm production abilities in patients with neurocognitive deficits

Deficits in rhythm perception and production have been reported in a variety of psychiatric, neurodevelopmental and neurologic disorders. Since correlations between rhythmic abilities and cognitive functions have been demonstrated in neurotypical individuals, we here investigate whether and how rhythmic abilities are associated with cognitive functions in 35 participants with neurocognitive deficits due to acquired brain lesions. We systematically assessed a diverse set of rhythm perception and production abilities including time and beat perception and finger-tapping tasks. Neuropsychological tests were applied to assess separable cognitive functions. Using multiple regression analyses we show that lower variability in aligning movements to a pacing sequence was predicted by better inhibitory control and better working memory performance. Working memory performance also predicted lower variability of rhythmic movements in the absence of an external pacing sequence and better anticipatory timing to sequences with gradual tempo changes. Importantly, these predictors remained significant for all regression models when controlling for other cognitive variables (i.e., cognitive flexibility, information processing speed, and verbal learning ability) and potential confounders (i.e., age, symptom strength of depression, manual dexterity, duration of illness, severity of cognitive impairment, and musical experience). Thus, all rhythm production abilities were significantly predicted by measures of executive functions. In contrast, rhythm perception abilities (time perception/beat perception) were not predicted by executive functions in this study. Our results, enhancing the understanding of cognitive underpinnings of rhythmic abilities in individuals with neurocognitive deficits, may be a first mandatory step to further potential therapeutic implications of rhythm-based interventions in neuropsychological rehabilitation.

Relationships Between Auditory Processing and Cognitive Abilities in Adults: A Systematic Review

PURPOSE

The contributions from the central auditory and cognitive systems play a major role in communication. Understanding the relationship between auditory and cognitive abilities has implications for auditory rehabilitation for clinical patients. The purpose of this systematic review is to address the question, "In adults, what is the relationship between central auditory processing abilities and cognitive abilities?"

METHOD

Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to identify, screen, and determine eligibility for articles that addressed the research question of interest. Medical librarians and subject matter experts assisted in search strategy, keyword review, and structuring the systematic review process. To be included, articles needed to have an auditory measure (either behavioral or electrophysiologic), a cognitive measure that assessed individual ability, and the measures needed to be compared to one another.

RESULTS

Following two rounds of identification and screening, 126 articles were included for full analysis. Central auditory processing (CAP) measures were grouped into categories (behavioral: speech in noise, altered speech, temporal processing, binaural processing; electrophysiologic: mismatch negativity, P50, N200, P200, and P300). The most common CAP measures were sentence recognition in speech-shaped noise and the P300. Cognitive abilities were grouped into constructs, and the most common construct was working memory. The findings were mixed, encompassing both significant and nonsignificant relationships; therefore, the results do not conclusively establish a direct link between CAP and cognitive abilities. Nonetheless, several consistent relationships emerged across different domains. Distorted or noisy speech was related to working memory or processing speed. Auditory temporal order tasks showed significant relationships with working memory, fluid intelligence, or multidomain cognitive measures. For electrophysiology, relationships were observed between some cortical evoked potentials and working memory or executive/inhibitory processes. Significant results were consistent with the hypothesis that assessments of CAP and cognitive processing would be positively correlated.

CONCLUSIONS

Results from this systematic review summarize relationships between CAP and cognitive processing, but also underscore the complexity of these constructs, the importance of study design, and the need to select an appropriate measure. The relationship between auditory and cognitive abilities is complex but can provide informative context when creating clinical management plans. This review supports a need to develop guidelines and training for audiologists who wish to consider individual central auditory and cognitive abilities in patient care.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24855174.

Dopamine dysregulation in Parkinson's disease flattens the pleasurable urge to move to musical rhythms

The pleasurable urge to move to music (PLUMM) activates motor and reward areas of the brain and is thought to be driven by predictive processes. Dopamine in motor and limbic networks is implicated in beat-based timing and music-induced pleasure, suggesting a central role of basal ganglia (BG) dopaminergic systems in PLUMM. This study tested this hypothesis by comparing PLUMM in participants with Parkinson's disease (PD), age-matched controls, and young controls. Participants listened to musical sequences with varying rhythmic and harmonic complexity (low, medium and high), and rated their experienced pleasure and urge to move to the rhythm. In line with previous results, healthy younger participants showed an inverted U-shaped relationship between rhythmic complexity and ratings, with preference for medium complexity rhythms, while age-matched controls showed a similar, but weaker, inverted U-shaped response. Conversely, PD showed a significantly flattened response for both the urge to move and pleasure. Crucially, this flattened response could not be attributed to differences in rhythm discrimination and did not reflect an overall decrease in ratings. For harmonic complexity, PD showed a negative linear pattern for both the urge to move and pleasure while healthy age-matched controls showed the same pattern for pleasure and an inverted U for the urge to move. This contrasts with the pattern observed in young healthy controls in previous studies, suggesting that both healthy aging and PD also influence affective responses to harmonic complexity. Together, these results support the role of dopamine within cortico-striatal circuits in the predictive processes that form the link between the perceptual processing of rhythmic patterns and the affective and motor responses to rhythmic music.

Music and neuro-cognitive deficits in depression

Background

Cognitive deficits are one of the core features of major depressive disorder (MDD) that play crucial role in functional recovery. Studies have explored cognitive deficits in MDD, however, given inconsistent results, especially in mild-moderate MDD. Recently, studies have explored music as cognitive ability in various clinical conditions. In MDD, large focus has been on evaluating emotion deficits and just a handful on music cognition. With growing evidence on use of music based intervention to target cognitive deficits, it is imperative to explore nature of music cognitive ability in MDD.

Aim

To examine musical and neuro-cognitive deficits in patients with mild-moderate MDD.

Methods

Patients diagnosed with mild or moderate MDD (n = 19) and matched healthy controls (HC) (n = 18) were evaluated on selected tests from NIMHANS Neuropsychological test battery and Montreal battery for evaluation of amusia (MBEA).

Results

MDD group performed significantly lower than HC on working memory (p = 0.007), verbal learning (p = 0.02) and retention (p = 0.03). Three indices were computed for a comprehensive evaluation. Groups did not differ significantly in any of the indices- focused attention, executive function, learning and memory as well as on music cognition. Focused attention and memory index predicted music cognition in HC and the combined group (MDD + HC) (p < 0.01). Attention alone contributed to 62.1% of variance in music cognition. Similarly, music cognition significantly predicted focused attention (p < 0.01).

Conclusion

Individuals with mild-moderate MDD show significant deficits in working memory, verbal learning and memory, however, not in music cognition. There exists a significant relationship between music cognition and attention, which could be implicated in use of music interventions to ameliorate cognitive deficits. Limitations of study include small sample size and heterogeneity. Future studies on larger cohort examining musical emotion perception and neurocognition is imperative to have deeper understanding of this debilitating condition.

Review: Subjective Time Perception, Dopamine Signaling, and Parkinsonian Slowness

The association between idiopathic Parkinson's disease, a paradigmatic dopamine-deficiency syndrome, and problems in the estimation of time has been studied experimentally for decades. I review that literature, which raises a question about whether and if dopamine deficiency relates not only to the motor slowness that is an objective and cardinal parkinsonian sign, but also to a compromised neural substrate for time perception. Why does a clinically (motorically) significant deficiency in dopamine play a role in the subjective perception of time's passage? After a discussion of a classical conception of basal ganglionic control of movement under the influence of dopamine, I describe recent work in healthy mice using optogenetics; the methodology visualizes dopaminergic neuronal firing in very short time intervals, then allows for correlation with motor behaviors in trained tasks. Moment-to-moment neuronal activity is both highly dynamic and variable, as assessed by photometry of genetically defined dopaminergic neurons. I use those animal data as context to review a large experimental experience in humans, spanning decades, that has examined subjective time perception mainly in Parkinson's disease, but also in other movement disorders. Although the human data are mixed in their findings, I argue that loss of dynamic variability in dopaminergic neuronal activity over very short intervals may be a fundamental sensory aspect in the pathophysiology of parkinsonism. An important implication is that therapeutic response in Parkinson's disease needs to be understood in terms of short-term alterations in dynamic neuronal firing, as has already been examined in novel ways—for example, in the study of real-time changes in neuronal network oscillations across very short time intervals. A finer analysis of a treatment's network effects might aid in any effort to augment clinical response to either medications or functional neurosurgical interventions in Parkinson's disease.

Hierarchical control as a shared neurocognitive mechanism for language and music

Although comparative research has made substantial progress in clarifying the relationship between language and music as neurocognitive systems from both a theoretical and empirical perspective, there is still no consensus about which mechanisms, if any, are shared and how they bring about different neurocognitive systems. In this paper, we tackle these two questions by focusing on hierarchical control as a neurocognitive mechanism underlying syntax in language and music. We put forward the Coordinated Hierarchical Control (CHC) hypothesis: linguistic and musical syntax rely on hierarchical control, but engage this shared mechanism differently depending on the current control demand. While linguistic syntax preferably engages the abstract rule-based control circuit, musical syntax rather employs the coordination of the abstract rule-based and the more concrete motor-based control circuits. We provide evidence for our hypothesis by reviewing neuroimaging as well as neuropsychological studies on linguistic and musical syntax. The CHC hypothesis makes a set of novel testable predictions to guide future work on the relationship between language and music.

Disentangling the effects of modality, interval length and task difficulty on the accuracy and precision of older adults in a rhythmic reproduction task

Studies on the functional quality of the internal clock that governs the temporal processing of older adults have demonstrated mixed results as to whether they perceive and produce time slower, faster, or equally well as younger adults. These mixed results are due to a multitude of methodologies applied to study temporal processing: many tasks demand different levels of cognitive ability. To investigate the temporal accuracy and precision of older adults, in Experiment 1, we explored the age-related differences in rhythmic continuation task taking into consideration the effects of attentional resources required by the stimulus (auditory vs. visual; length of intervals). In Experiment 2, we added a dual task to explore the effect of attentional resources required by the task. Our findings indicate that (1) even in an inherently automatic rhythmic task, where older and younger adult’s general accuracy is comparable, accuracy but not precision is altered by the stimulus properties and (2) an increase in task load can magnify age-related differences in both accuracy and precision.

Subjective judgments of rhythmic complexity in Parkinson's disease: Higher baseline, preserved relative ability, and modulated by tempo

Previous research has demonstrated that people with Parkinson's disease (PD) have difficulties with the perceptual discrimination of rhythms, relative to healthy controls. It is not however clear if this applies only to simpler rhythms (a so called "beat-based" deficit), or if it is a more generalized deficit that also applies to more complex rhythms. Further insight into how people with PD process and perceive rhythm can refine our understanding of the well known problems of temporal processing in the disease. In this study, we wanted to move beyond simple/complex-dichotomy in previous studies, and further investigate the effect of tempo on the perception of musical rhythms. To this end, we constructed ten musical rhythms with a varied degree of complexity across three different tempi. Nineteen people with PD and 19 healthy controls part-took in an internet based listening survey and rated 10 different musical rhythms for complexity and likeability. In what we believe is the first study to do so, we asked for the participants subjective ratings of individual rhythms and not their capacity to directly compare or discriminate between them. We found an overall between-group difference in complexity judgments that was modulated by tempo, but not level of complexity. People with PD rated all rhythms as more complex across tempi, with significant group differences in complexity ratings at 120 and 150bpm, but not at 90bpm. Our analysis found a uniform elevated baseline for complexity judgments in the PD-group, and a strong association between the two groups' rank-ordering the rhythms for complexity. This indicates a preserved ability to discriminate between relative levels of complexity. Finally, the two groups did not significantly differ in their subjective scoring of likeability, demonstrating a dissimilarity between judgment of complexity and judgment of likeability between the two groups. This indicates different cognitive operations for the two types of judgment, and we speculate that Parkinson's disease affects judgment of complexity but not judgment of likeability.

Compensatory task-specific hypersensitivity in bilateral planum temporale and right superior temporal gyrus during auditory rhythm and omission processing in Parkinson's disease

Persons with Parkinson's disease have general timing deficits and have difficulties in rhythm discrimination tasks. The basal ganglia, a crucial part of Parkinson's disease pathology, is believed to play an important role in rhythm and beat processing, with a possible modulation of basal ganglia activity by level of rhythmic complexity. As dysfunction in basal ganglia impacts function in other brain areas in Parkinson's disease during temporal processing, investigating the neuronal basis for rhythm processing is important as it could shed light on the nature of basal ganglia dysfunction and compensatory mechanisms. We constructed an auditory beat-omission fMRI paradigm with two levels of rhythm complexity, to investigate if and where persons with Parkinson's disease showed abnormal activation during rhythm and omission processing, and whether such activations were modulated by the level of rhythmic complexity. We found no effect of complexity, but found crucial group differences. For the processing of normal rhythm presentations, the Parkinson-group showed higher bilateral planum temporal activity, an area previously associated with the processing of complex patterns. For the omissions, the Parkinson-group showed higher activity in an area in the right superior temporal gyrus previously associated with detection of auditory omissions. We believe this shows a pattern of "hypersensitive" activity, indicative of task-specific, compensatory mechanisms in the processing of temporal auditory information in persons with Parkinson's disease.

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

Behavioral studies indicate that persons with Parkinson's disease have complexity dependent problems with the discrimination of auditory rhythms. Furthermore, neuroimaging studies show that rhythm processing activates many brain areas that overlap with areas affected by Parkinson's disease (PD). This study sought to investigate the neural correlates of rhythm processing in PD and healthy controls, with a particular focus on rhythmic complexity. We further aimed to investigate differences in brain activation during initial phases of rhythm processing. Functional magnetic resonance imaging was used to scan 15 persons with Parkinson's disease and 15 healthy controls while they listened to musical rhythms with two different levels of complexity. Rhythmic complexity had no significant effect on brain activations, but patients and controls showed differences in areas related to temporal auditory processing, notably bilateral planum temporale and inferior parietal lobule. We found indications of a particular sequential or phasic activation pattern of brain activity, where activity in caudate nucleus in the basal ganglia was time‐displaced by activation in the saliency network—comprised of anterior cingulate cortex and bilateral anterior insula—and cortical and subcortical motor areas, during the initial phases of listening to rhythms. We relate our findings to core PD pathology, and discuss the overall, rhythm processing related hyperactivity in PD as a possible dysfunction in specific basal ganglia mechanisms, and the phasic activation pattern in PD as a reflection of a lack of preparatory activation of task‐relevant brain networks for rhythm processing in PD.

Music therapy for mental disorder and mental health: the untapped potential of Indian classical music

Music is a universal human trait. The healing power of music has been acknowledged in almost all traditions of music. Music therapy is moving from a social-science model focusing on overall health and well-being towards a neuroscience model focusing on specific elements of music and its effect on sensorimotor, language and cognitive functions. The handful of evidence-based music therapy studies on psychiatric conditions have shown promising results. Traditional music, such as Indian classical music, has only recently been evaluated in evidence-based research into music therapy. The need for systematic research in this area is underscored.