Supporting Physical Activity and Quality of Life in Older Adults with Coronary Heart Disease: Development of a Web-Based Nursing Intervention.

The metronome response task is a sustained attention task that requires generating a response synchronized with an auditory or visual metronome. Many tremor physiology studies, particularly those investigating pathological tremors such as essential tremor and parkinsonian tremor using tremor resetting paradigms, involve voluntarily mimicked rhythmic tremor/voluntary rhythmic movements as a control group activity. Although rhythmic movements mimicking tremor and the metronome response task originate from different experimental traditions, both paradigms involve rhythmic motor output synchronized to an external rhythm and require sustained attention and motor control. Conceptually, rhythmic movements mimicking tremor could be considered as a specific form of the metronome response task, suggesting a potential overlap in the underlying sensorimotor and attentional mechanisms. A metronome, which visually represents a rhythmic hand movement, may act as a stimulus that activates the mirror neuron system through the perception of movement. The mirror neuron system reflects the activity of specialized neurons within motor regions and is activated not only during the performance of manual actions but also during their visual observation or auditory perception, a mechanism referred to as the resonance account. Motor facilitation during action perception is supported by both top-down predictive coding and bottom-up resonance explanation. In humans, motor system activity has been shown to be modulated by both visual and auditory action-related stimuli. According to observation–execution matching theory, watching a motor action increases the excitability of the corresponding motor representation in the primary motor cortex (M1). Supporting these, motor evoked potential (MEP) amplitudes in hand muscles were found to be greater which indicates the task related excitability increase of M1 when observing hand and arm movements of others. Cross-frequency coupling is believed to organize neural timing across multiple timescales, whereas cross-modal phase reset al.igns this timing to the external sensory events. These two mechanisms, controlled by attention, are responsible for the functional communication between the auditory and visual cortices. Intracortical alpha-band power, a cross-frequency coupling, is modulated by the delta phase. This cross-frequency coupling is influenced by attention. Entrainment is the basic mechanism of selective attention, and it is not limited to the local sensory cortex but also extends to the widespread cortical regions of the brain including auditory, visual, parietal, and frontal cortices. These findings suggest that the entrainment is under the control of higher order attentional networks. Accordingly, different metronome modalities (auditory, visual, bimodal such as combined auditory-visual) may theoretically engage these networks differently and potentially influence M1 excitability to varying degrees.