Attentional modulation of functional connectivity in the face processing network of the brain

Visual attention is an important part of our every day processing, as it can mod- ulate responses in our brain. Which exact effect attention has on face processing, and the corresponding face processing network, is not yet fully clear. The present study investigates the modulation of the brain’s neuronal activity and functional connectivity based on visual attention during processing of facial stimuli. For this, task-based magnetoencephalography (MEG) was recorded from ten participants. The participants were presented with composite face stimuli, consisting of an up- per part and a lower part, separated by a noise mask, of a face. These parts were oscillated at different frequencies. Participants had to then attend to the eyes, the mouth or the facial identity of the facial stimulus. The resulting data was analyzed in theta, alpha, beta and gamma frequency bands in respect to brain activation and functional connectivity. Ten regions of interest related to visuospatial attention and face processing were selected. The results indicate modulation of the brain activ- ity in respect to attention onto the different facial features (eyes, mouth, identity) in different frequency bands. Further, the functional connectivity also suggested modulated connectivity in similar lines, dependent on the attended face feature. These results are in line with previous research in respect to the role of the different frequency bands in visual attention and face processing.