AUTHOR=Burke John F. , Merkow Maxwell B. , Jacobs Joshua , Kahana Michael J. , Zaghloul Kareem A. TITLE=Brain computer interface to enhance episodic memory in human participants JOURNAL=Frontiers in Human Neuroscience VOLUME=8 YEAR=2015 URL=https://www.frontiersin.org/journals/human-neuroscience/articles/10.3389/fnhum.2014.01055 DOI=10.3389/fnhum.2014.01055 ISSN=1662-5161 ABSTRACT=

Recent research has revealed that neural oscillations in the theta (4–8 Hz) and alpha (9–14 Hz) bands are predictive of future success in memory encoding. Because these signals occur before the presentation of an upcoming stimulus, they are considered stimulus-independent in that they correlate with enhanced memory encoding independent of the item being encoded. Thus, such stimulus-independent activity has important implications for the neural mechanisms underlying episodic memory as well as the development of cognitive neural prosthetics. Here, we developed a brain computer interface (BCI) to test the ability of such pre-stimulus activity to modulate subsequent memory encoding. We recorded intracranial electroencephalography (iEEG) in neurosurgical patients as they performed a free recall memory task, and detected iEEG theta and alpha oscillations that correlated with optimal memory encoding. We then used these detected oscillatory changes to trigger the presentation of items in the free recall task. We found that item presentation contingent upon the presence of pre-stimulus theta and alpha oscillations modulated memory performance in more sessions than expected by chance. Our results suggest that an electrophysiological signal may be causally linked to a specific behavioral condition, and contingent stimulus presentation has the potential to modulate human memory encoding.