ReSync: Correcting the trial-to-trial asynchrony of event-related brain potentials to improve neural response representation

Abstract

For various reasons, the brain response activities in EEG signals are not perfectly synchronized from trial to trial with respect to event markers – a problem commonly referred to as ERP latency jitter. EEG experimental technologies have been greatly advanced to reduce technical timing errors so as to reduce the jitter. However, there are intrinsic sources of jitter that are difficult, if not impossible, to remove. The problem becomes more complicated when facing multiple sub-components with different jitter. The jitter issue renders trial-averaged ERP inaccurate at best and misleading at worst. Effectively correcting the jitter has profound significance in brain research. I present a simple method and easy-to-use toolbox ReSync for correcting ERP jitters based on signal processing theories and techniques. ReSync can be used to correct multiple overlapping ERP sub-components with different degrees of jitter without affecting each other (including the static one). The theories, principles, technical details, and limitations of ReSync were presented in this paper, along with a series of simulation and real data examples for evaluating and validating the method.

Peak selection and latency jitter correction in developmental event‐related potentials

“…Second, approaches to resynchronizing ERP data may be outside of the technical skillset of many ERP researchers. To address these concerns, the ReSync MATLAB toolbox (Ouyang, 2020) Not all components are equally benefitted from the use of ReSync.…”

“…For example, a low signal-to-noise ratio may interfere with appropriate realignment due to arbitrary latency identification (Ouyang, 2020).…”

“…A component that demonstrates variable latency and a sharp peak is more appropriate for ReSyncing than a blunt component equal in latency variability. Ouyang (2020) recommends continued data analysis with the standard average ERP in these instances and when ERP compo-nent latency is not very variable. Decisions about the execution of the ReSync program can be made at the individual level.…”

“…Variable latency ERP responses may be observed across and within individuals' data, which is known as latency jitter. We will discuss the impact of latency jitter on appropriate time window selection and introduce a possible solution, the ReSync toolbox (Ouyang, 2020). A summary of these three approaches and the ReSync procedure, including advantages, disadvantages, and…”

“…amplitude of the P1, N290, and P400 ERP components and application of the ReSync latency jitter correction MATLAB toolbox(Ouyang, 2020) to infant and child EEG data. A graphic representation of the pipeline is depicted in Figure1.…”