Abstract
Rhythmic neural activities are ubiquitous and play key roles in various cognitive functions. Recent studies, by employing a time-resolved behavioral measurement, have revealed neurophysiologically relevant oscillations directly in visual attentional behavior (‘behavioral oscillation’), implicating that multiple locations get sampled alternatively in a theta-band rhythm (Landau & Fries, 2012; Fiebelkorn et al., 2013; Song et al., 2014). Furthermore, our recent work, by using a masked priming paradigm, demonstrate that similar to multi-location rhythmic sampling, multiple perceptual predictions occurring at the same spatial location are conveyed in various phases of a theta-band rhythm (see Huang, Chen and Luo, VSS2015). However, it is unknown which brain regions underlie the ‘behavioral oscillation’ in visual attention. To investigate the neural underpinning of ‘behavioral oscillations’, we conducted an fMRI study to measure human brain responses by employing the masked priming paradigm in combination with a time-resolved psychophysical approach. Behavioral results replicate our masked priming oscillation findings (see Huang, Chen and Luo, VSS2015). Importantly, complementing to the behavioral oscillation findings, preliminary fMRI results demonstrate theta-band oscillations as well as out-of-phase relationship between congruent and incongruent conditions in several brain regions, including occipital visual areas, cerebellum, motor cortex, and frontal regions. These results provide critical constraints for developing a neural model to understand the attentional mechanism underlying behavioral oscillations. Based on these results, we propose a model that suggests frontal cortex may generate and coordinate perceptual predictions through an oscillation-based temporal organization scheme, and these perceptual predictions would then be conveyed to modulate neural activity in sensory cortex and motor related brain regions, leading to the observed ‘behavioral oscillations’ in masked priming.
Meeting abstract presented at VSS 2015