Investigating auditory electrophysiological measures of participants with mild cognitive impairment and Alzheimer’s disease: A systematic review and meta‐analysis of event‐related potential studies

Abstract

Background: Objectively measuring auditory functions has been proposed as an avenue in differentiating normal age-related cognitive dysfunction from Alzheimer's disease (AD) and its prodromal states. Previous research has suggested auditory eventrelated potentials (AERPs) to be non-invasive, cost-effective and efficient biomarkers for the diagnosis of AD. The objective of this paper is to review the published literature on AERPs measures in older adults diagnosed with AD and those at higher risk of developing AD, i.e., mild cognitive impairment (MCI) and subjective cognitive decline (SCD). Method:The search was performed on six major electronic databases (Ovid MED-LINE, OVID EMBASE, PsycINFO, PubMed, Scopus and CINAHL Plus). Articles identified prior to 7th May 2019 were considered for this review. A random effects metaanalysis and analysis of between study heterogeneity was conducted using the Comprehensive Meta-Analysis software. Result:The search identified 1076 articles; 74 articles met the full inclusion criteria and were included in the systematic review, and 47 articles were included into the analyses. Pooled analysis suggests that AD participants can be differentiated from controls due to significant delays in ABR, N100, P200, N200 and P300 latencies. P300 amplitude was significantly smaller in AD participants compared to controls. P300 latencies differed significantly between MCI participants and controls based on the pooled analysis. Conclusion:The findings of this review indicate that some AERPs may be valuable biomarkers of AD. In conjunction with currently available clinical and neuropsychological assessments, AERPs can aid in screening and diagnosis of prodromal AD.

Understanding the Relationship Between Age-Related Hearing Loss and Alzheimer’s Disease: A Narrative Review

“…A recent meta-analysis reported that higher processing of sensory information, as reflected by late latency AERPs N100 and P200, are impaired in those with AD when compared to healthy controls [ 204 ]. The N100 and P200 have been proposed to be produced by the primary and secondary auditory cortex, hence, changes in the appearance of these responses are thought to reflect measurable impairments in processing and perceiving variations in an auditory information [ 205, 206 ].…”

“…Similar to results observed in behavioral CAP tests, particularly SSI-ICM, objective measures of discrimination, perception, and classification of auditory signals using N200 latency have also been shown to be delayed in those with cognitive impairment associated with AD [ 196, 204, 207 ]. The neural generators of the N200 peak include the auditory cortex and thalamic region [ 208, 209 ] and significant delays in the N200 latency have been observed in participants with MCI and those with AD [ 204, 207 ].…”

“…The P300, another late latency cortical AERP, is the most widely studied AERP for cognitive function. Research has suggested that this response is altered with the development of neurodegenerative diseases, showing as reduced P300 amplitude and increased P300 latency in those with cognitive impairment associated with AD compared to healthy controls [ 204, 210, 211 ]. Multiple brain regions have been associated to the generation of the P300 response and these include the temporal parietal junction, medial temporal lobe, frontal lobe, and parietal cortex [ 212, 213 ].…”

“…Therefore, P300 is proposed to reflect cortical activity as it is dependent on functions including discrimination, attention, and memory in order to be elicited. A meta-analysis revealed that those with MCI and AD have significantly longer P300 latencies in comparison to healthy age-matched controls [ 204 ], indicating dysfunctional attention-driven discrimination processing and reduced classification speed in task processing in those with cognitive decline associated with AD [ 193, 194 ]. Although multiple meta-analyses indicate that P300 latency measures do not significantly differ between MCI and AD participants [ 204, 214 ], a longitudinal study found that MCI participants that developed probable AD after a 5-year period had significantly longer baseline P300 latency in comparison to MCI participants that did not go on to develop AD [ 215 ].…”

Predictive Power of Cognitive Biomarkers in Neurodegenerative Disease Drug Development: Utility of the P300 Event-Related Potential

“…Several studies have also shown that ERP P300 can detect differences in P300 latency in people with a family history of AD as compared to age-matched controls [39,[54][55][56]. Additionally, results of several meta-analyses of ERP P300 latency studies in patients with AD and MCI support the use of ERP P300 as a biological marker for prodromal AD [57][58][59][60][61]. While most studies have reported a decreased P300 amplitude in patients with AD [62], there have been some exceptions, in which amplitude in patients with AD was reported as being equivalent to that in healthy controls [53,63].…”