RT Journal Article
SR Electronic
T1 Neural measures of subsequent memory reflect endogenous variability in cognitive function
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 576173
DO 10.1101/576173
A1 Christoph T. Weidemann
A1 Michael J. Kahana
YR 2019
UL http://biorxiv.org/content/early/2019/03/13/576173.abstract
AB Humans cognition exhibits a striking degree of variability: Sometimes we rapidly forge new associations whereas at others new information simply does not stick. Although strong correlations between neural activity during encoding and subsequent retrieval performance have implicated such “subsequent memory effects” (SMEs) as important for understanding the neural basis of memory formation, uncontrolled variability in external factors that also predict memory performance confounds the interpretation of these effects. By controlling for a comprehensive set of external variables, we investigated the extent to which neural correlates of successful memory encoding reflect variability in endogenous brain states. We show that external variables that reliably predict memory performance have only minimal effects on electroencephalographic (EEG) correlates of successful memory encoding. Instead, the brain activity that is diagnostic of successful encoding primarily reflects fluctuations in endogenous neural activity. These findings link neural activity during learning to endogenous states that drive variability in human cognition.