Causal role of different frequencies of brain rhythms for the processing of conscious and unconscious perceptual contents

The study of consciousness is fundamental to understanding how the brain processes information. Over the years, many research studies have undertaken the task of dissociating the mechanisms underlying the processing of conscious and unconscious information. Neural oscillations are fundamental to information processing and communication in the brain. While many studies have shown a correlational and causational role of these neural oscillations for the maintenance of conscious information, there exists a dearth of causational studies that show the dissociable role of neural oscillations in the processing of unconscious information. In this study, we used high-definition transcranial alternating current stimulations to entrain the bilateral occipital regions of the brain with alpha, beta, or theta rhythms while participants performed a delayed target-probe discrimination task. Through neuromodulation, we showed that entrainment of beta rhythms improved the participants’ performance in trials reported as ‘seen’ or conscious by facilitating the short-term memory for task relevant information. On the other hand, alpha modulation enhanced participants’ performance in trials reported as ‘unseen’ or unconscious which has not been predicted by any existing consciousness theories.

Author dc:creator

• Sankaranarayanan, Shruthi

Advisor dc:contributor.advisor

• Reinhart, Robert M. G.

• Neurosciences

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/2144/46254

OAI identifier oai:identifier

oai:open.bu.edu:2144/46254