Pearl and pitfalls in brain functional analysis by event-related potentials: a narrative review by the Italian Psychophysiology and Cognitive Neuroscience Society on methodological limits and clinical reliability—part II

Abstract

This review focuses on new and/or less standardized event-related potentials methods, in order to improve their knowledge for future clinical applications. The olfactory event-related potentials (OERPs) assess the olfactory functions in time domain, with potential utility in anosmia and degenerative diseases. The transcranial magnetic stimulation-electroencephalography (TMS-EEG) could support the investigation of the intracerebral connections with very high temporal discrimination. Its application in the diagnosis of disorders of consciousness has achieved recent confirmation. Magnetoencephalography (MEG) and eventrelated fields (ERF) could improve spatial accuracy of scalp signals, with potential large application in pre-surgical study of epileptic patients. Although these techniques have methodological limits, such as high inter-and intraindividual variability and high costs, their diffusion among researchers and clinicians is hopeful, pending their standardization.

M1 Large-scale Network Dynamics Support Human Motor Resonance and Its Plastic Reshaping

“…TMS-EEG enables the real-time exploration of cortical reactivity at a whole-brain level by examining TMS-evoked potentials (TEPs). TEPs are considered a reliable indicator of cortical excitability, offering insights into the activation state of the stimulated region (Casarotto et al, 2010;de Tommaso et al, 2020;Miniussi & Thut, 2010). Crucially, the analysis of TEPs allows us to observe how the activity triggered by TMS propagates over time and space, reaching distant regions connected through functional pathways (Bortoletto, Veniero, Thut, & Miniussi, 2015;Pisoni, Mattavelli, et al, 2018;Rogasch & Fitzgerald, 2013).…”

EMG-projected MEG High-Resolution Source Imaging of Human Motor Execution: Brain-Muscle Coupling above Movement Frequencies

“…Different modeling approaches and frequency bands have been employed to map M1 cortex activity. For example, MEG event-related desynchronization (ERD) localized M1 cortex activity in the beta band (15-30 Hz) using a beamformer-based spatial filter (Bulubas et al, 2020;Tarapore et al, 2012) whereas MEG evoked-related field (ERF) components localized M1 cortex activity within a broad frequency band setting (e.g., DC to 30 Hz or 100 Hz) using dipole modeling (Bowyer et al, 2020;de Tommaso et al, 2020;Huang et al, 2004;Spooner et al, 2022) and beamformer (Cheyne et al, 2006;Gaetz et al, 2010) approaches. MEG gamma-band M1 activity was mainly found postmovement-onset using a seed virtual sensor placed at M1, which was first located from evokedrelated finger movement components (Cheyne et al, 2008;Huo et al, 2010).…”