Neurophysiological Assessments in Parkinson's Disease

Neurophysiological assessments in Parkinson’s disease encompass a suite of techniques that probe both peripheral and central nervous system function. Peripheral auditory and vestibular evaluations, such as pure-tone audiometry, distortion product otoacoustic emissions and vestibular evoked myogenic potentials, offer insight into cochlear and brainstem involvement in motor and non-motor symptomatology. Evoked potential studies, including brainstem auditory-evoked potentials and visual-evoked potentials, reveal delays or amplitude changes in latencies that may correlate with disease severity or asymmetry of motor signs. At the cortical level, event-related potentials and magnetoencephalography capture alterations in oscillatory dynamics and attentional processing, shedding light on executive dysfunction and the role of frontostriatal circuits. Together, these modalities provide objective biomarkers for early diagnosis, subtyping and monitoring of disease progression, and they inform tailored rehabilitative strategies to mitigate balance, gait and communication impairments globally.

Research from Nature Portfolio

Recent work has explored the link between dizziness and vestibular function in Parkinson’s disease patients without orthostatic hypotension. Electrophysiological recordings of ocular and cervical vestibular evoked myogenic potentials demonstrated a higher prevalence of absent oVEMP responses in patients reporting dizziness. The reduced amplitude and frequency of oVEMPs suggest vestibular hypofunction as a contributor to non-motor symptoms, independent of classic autonomic causes. This finding highlights the potential for vestibular rehabilitation to alleviate dizziness and improve quality of life in a subset of patients.

Neurophysiological Assessments in Parkinson's Disease publication trend

The graph below shows the total number of articles in neurophysiological assessments in parkinson's disease across all publications each year (not limited to Nature Index journals).

Technical terms

Basal ganglia: Subcortical nuclei involved in motor control and cognitive functions, often affected by dopaminergic neuron loss in Parkinson’s disease.

Dopamine transporter: Membrane protein that regulates synaptic dopamine levels by reuptake into presynaptic terminals; its availability reflects nigrostriatal integrity.

Vestibular evoked myogenic potential (VEMP): Electrophysiological response recorded from neck or ocular muscles in response to acoustic stimuli, reflecting otolithic and vestibular nerve function.

Ocular VEMP (oVEMP): VEMP recorded from periocular musculature that primarily assesses utricular and superior vestibular pathways.

Magnetoencephalography (MEG): Non-invasive technique measuring magnetic fields produced by neuronal currents, used to map cortical oscillations during cognitive and motor tasks.

References

1. Association between hearing sensitivity and dopamine transporter availability in Parkinson’s disease. Brain Communications (2023).
2. Auditory- and Vestibular-Evoked Potentials Correlate with Motor and Non-Motor Features of Parkinson’s Disease. Frontiers in Neurology (2017).
3. Evoked potential changes in patients with Parkinson's disease. Brain and Behavior (2017).
4. Dizziness in Parkinson’s disease patients is associated with vestibular function. Scientific Reports (2021).
5. Impaired Early Attentional Processes in Parkinson’s Disease: A High-Resolution Event-Related Potentials Study. PLOS ONE (2015).
6. Cortical oscillatory dysfunction in Parkinson disease during movement activation and inhibition. PLOS ONE (2022).