A systematic review of cognitive event-related potentials in mild cognitive impairment and Alzheimer’s disease

Abstract

This systematic review examined whether event-related potentials (ERPs) during higher cognitive processing can detect subtle, early signs of neurodegenerative disease. Original, empirical studies retrieved from PsycINFO and PubMed were reviewed if they analyzed patterns in cognitive ERPs (³150ms post-stimulus) differentiating mild cognitive impairment (MCI), Alzheimer's disease (AD), or cognitively intact elders who carry AD risk through the Apolipoprotein-E ε4 allele (ε4+) from healthy older adult controls (HC). The 100 studies meeting inclusion criteria (MCI=47; AD=47; ε4+=6) analyzed N200, P300, N400, and occasionally, later components. While there was variability across studies, patterns of reduced amplitude and delayed latency were apparent in pathological aging, consistent with AD-related brain atrophy and cognitive impairment. These effects were particularly evident in advanced disease progression (i.e., AD > MCI) and in later ERP components measured during complex tasks. Although ERP studies in intact ε4+ elders are thus far scarce, a similar pattern of delayed latency was notable, along with a contrasting pattern of increased amplitude, consistent with compensatory neural activation. This limited work suggests ERPs might be able to index early neural changes indicative of future cognitive decline in otherwise healthy elders. As ERPs are also accessible and affordable relative to other neuroimaging methods, their addition to cognitive assessment might substantively enhance early identification and characterization of neural dysfunction, allowing opportunity for earlier differential diagnosis and targeting of intervention. To evaluate this possibility there is urgent need for well-powered studies assessing late cognitive ERPs during complex tasks, particularly in healthy elders at risk for cognitive decline.

Temporal Dynamics of Event-Related Potentials during Inhibitory Control Characterize Age-Related Neural Compensation

“…Specifically, compensatory activation is most consistently evident in elders during low-to-moderate task demand, when their performance is comparable with young groups, while decreased activation becomes evident with high task demand and reduced task performance, which is indicative of depleted neural reserves [ 63 ]. P300 was sensitive to this depletion of neural reserve where N200 was not, which is consistent with previous studies showing P300 sensitivity to early neural decline amongst healthy, cognitively intact elders with genetic risk for Alzheimer’s disease [ 66 ]. Thus, our findings suggest that the neural mechanisms underlying motor response inhibition and performance evaluation and monitoring via P300 likely decline earlier than N200-related conflict monitoring sources in healthy, typical aging.…”

Induction of specific brain oscillations may restore neural circuits and be used for the treatment of Alzheimer's disease

“…The power of predicting cognitive decline using signatures of brain rhythms as a potential precursor to this decline is of growing interest. In the past, it has been posited that electrophysiology alone cannot diagnose AD, while EEG is a cost-and timeeffective measure to screen individuals with distinct signatures of conversion to AD [112]. Previous work has demonstrated the ability to extract relevant biomarker information from electrophysiology, across different bands and stimulation protocols [113][114][115].…”

Single-Channel EEG Features Reveal an Association With Cognitive Decline in Seniors Performing Auditory Cognitive Assessment

“…The auditory stimuli included a simple detection task involving musical stimuli. We chose this particular detection task because it is one of the most commonly used tasks to measure differences in EEG activity between cognitive decline groups ( Paitel et al, 2021 ), and it requires relatively low cognitive load levels, which is well suited for cognitive decline states ( Debener et al, 2005 ). We used this cognitive assessment on senior participants in different cognitive states (from healthy seniors to cognitive decline patients, as determined by MMSE score independently obtained by clinicians), and on healthy young participants.…”