Generation of slow BOLD signals from coupled neural mass models in the gamma range (BARCCSYN 2022 poster)

Poster presented at BARCCSYN 2022 (Barcelona, May 2022). Earlier whole-brain models generated BOLD-like signals from neural mass models by extracting the power envelope of the gamma band. Here the Balloon model transduces synaptic activity into BOLD, and the result is compared with the gamma power envelope. Two symmetrically coupled pyramidal-interneuron gamma (PING) neural masses with different external inputs oscillate at different gamma frequencies; coupling produces low-frequency components in the firing-rate spectrum through beating, whose frequency decreases with the coupling gain and which disappear above the gain at which both masses lock to one frequency. Without noise, the Balloon BOLD signal and the filtered gamma envelope correlate at 0.97; with input noise, BOLD follows the filtered noise (0.94) and the gamma envelope only weakly (0.15). In a whole-brain model on a diffusion-MRI connectome, the asymmetry of the inputs received by each parcel spreads the peak frequencies and slow components are again generated by beating. Funded by the European Union's Horizon 2020 programme, grant agreement No 101017716 (Neurotwin). The file is the poster as presented in 2022, archived in November 2026 with a catalogue stamp; its content is unchanged.