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Parkinson's disease (PD) is a pervasive neurodegenerative disorder that currently affects~ 137,000 people in the UK. While PD was traditionally assumed to be a paradigmatic movement disorder increasing evidence suggests that non-motor symptoms, including cognitive and psychiatric impairment and autonomic dysfunction, are central to the manifestation of PD (Chaudhuri et al., 2006). PD is currently incurable and irreversible. Thus, the identification of potential risk factors associated with PD onset is of particular clinical and economic importance. When considering non-genetic risk factors, recent evidence suggests that clinically diagnosed hearing loss (HL) is a risk factor for incident PD (eg Simonet et al., 2022; Schrag et al., 2022). Conversely, alternative studies have observed that self-reported HL is not significantly risk factor for later incident PD (Readman et al., 2023). The discrepancies between these findings could speak to the mechanism underlying HL antedating PD motor manifestations. Clinical diagnosis of HL relies upon pure tone audiometry assessment (PTA). PTA is thought to depend primarily upon the health of the outer hair cells, and additionally cochlear transduction by the inner hair cells (Pickles, 2013). Although PTA can be influenced by psychophysiological factors (eg, patient attention) and demographic factors (eg biological sex)(Carl et al., 2023), it is largely assumed that PTA outcomes primarily derive from peripheral sensory processes. In contrast, self-reported hearing capabilities are heavily influenced by non-auditory factors including demographic, socioeconomic, and lifestyle factors (Tsimpida et al., 2020). Hence …