Publication date: Jun 16, 2020
To investigate face individuation (FI), a critical brain function in the human species, an oddball fast periodic visual stimulation (FPVS) approach was recently introduced (Liu-Shuang et al., 2014). In this paradigm, an image of an unfamiliar “base” facial identity is repeated at a rapid rate F (e.g., 6 Hz) and different unfamiliar “oddball” facial identities are inserted every n item, at a F/n rate (e.g., every 5 item, 1.2 Hz). This stimulation elicits FI responses at F/n and its harmonics (2F/n, 3F/n, etc.), reflecting neural discrimination between oddball vs. base facial identities, which is quantified in the frequency-domain of the electroencephalogram (EEG). This paradigm, used in 20 published studies, demonstrates substantial advantages for measuring FI in terms of validity, objectivity, reliability, and sensitivity. Human intracerebral recordings suggest that this FI response originates from neural populations in the lateral inferior occipital and fusiform gyri, with a right hemispheric dominance consistent with the localization of brain lesions specifically affecting facial identity recognition (prosopagnosia). Here we summarize the contributions of the oddball FPVS framework towards understanding FI, including its (a)typical development, with early studies supporting the application of this technique to clinical testing (e.g., Autism Spectrum Disorder). This review also includes an in-depth analysis of the paradigm’s methodology, with guidelines for designing future studies. A large-scale group analysis compiling data across 130 observers provides insights into the oddball FPVS FI response properties. Overall, we recommend the oddball FPVS paradigm as an alternative approach to behavioral or traditional event-related-potential EEG measures of face individuation.
|disease||MESH||Autism Spectrum Disorder|