Abstract
Object recognition relies on both specific knowledge of object categories and general brain states, such as arousal. Here, we hypothesized that these distinct phenomena, “specific” and “general”, are reflected in spontaneous fluctuations of neural activity and independently influence recognition of forthcoming object stimuli. We recorded magnetoencephalographic (MEG) activity in participants (N=24) who viewed images of objects presented at recognition threshold. The stimuli were presented briefly at a contrast that was titrated individually for each subject, and, as a result, the subjects reported successful recognition in ~50% of the repeated trials. Using multivariate pattern analysis applied to whole-brain neural signals recorded before stimulus onset, we found two neural processes influencing subjective recognition of forthcoming stimuli: a general process, which ignored stimulus category and correlated with pupil size, and a specific process, which influenced recognition in category-specific manner. We employed Signal Detection Theory (SDT) measures to delineate a role of each spontaneous neural activity process in object recognition behavior. We found that the two processes are doubly dissociable: the general process shifted the criterion of recognition but had no effect on sensitivity, whereas the specific process enhanced sensitivity with no effect on criterion. These findings reveal a dual role of spontaneously-emerging neural activity patterns in object recognition. Furthermore, they shed light on a mechanism of interaction between spontaneous brain activity and sensory input - a fundamental process underlying perceptual inference.
Acknowledgement: This research was supported by National Science Foundation (BCS-1753218, to BJH). BJH further acknowledges support by Klingenstein-Simons Neuroscience Fellowship.