Poster Session: Using OPM-MEG to study the timecourse of human contrast discrimination

The International Brain Laboratory (IBL) is a large-scale project collecting multiunit measurements from the mouse brain during a simple 2AFC perceptual decision task. The goal is to characterise the flow of information across the brain from sensory input areas through to motor outputs, and the way that this information flow can be modulated by priors. Our lab is translating the IBL task to humans using a combination of psychophysics and neuroimaging. Here we describe the results from a pilot study using a novel type of neuroimaging (OPM-MEG). We first describe the adaptations necessary to alter the original rodent task to make it appropriate for human subjects. We then present behavioral and neuroimaging data obtained using this modified paradigm. Human psychophysical responses recapitulate key features of the rodent behavioural data - including the effect of perceptual priors or 'bias'. Psychophysical response functions have the same form and bias dependency as those obtained from mice. Using the MEG data we are able to decode key features of the IBL paradigm including visual stimuli, responses, bias blocks and feedback in a time-resolved manner. We show that OPM-MEG responses are consistent with fMRI responses obtained in our lab using the same paradigm. We conclude that multimodal neuroimaging techniques (OPM-MEG and fMRI) can be applied to the IBL task allowing us to relate neuronal-level recordings in rodents with whole-brain population responses in humans.