title: Resting state connectivity immediately following learning correlates with subsequent sleep-dependent enhancement of motor task performance.
abstract: There is ongoing debate concerning the functions of resting-state brain activity. Prior work demonstrates that memory encoding enhances subsequent resting-state functional connectivity within task-relevant networks and that these changes predict better recognition. Here, we used functional connectivity MRI (fcMRI) to examine whether task-induced changes in resting-state connectivity correlate with performance improvement after sleep. In two separate sessions, resting-state scans were acquired before and after participants performed a motor task. In one session participants trained on the motor sequence task (MST), a well-established probe of sleep-dependent memory consolidation, and were tested the next day, after a night of sleep. In the other session they performed a motor control task (MCT) that minimized learning. In an accompanying behavioral control study, participants trained on the MST and were tested after either a night of sleep or an equivalent interval of daytime wake. Both the fcMRI and the sleep control groups showed significant improvement of MST performance, while the wake control group did not. In the fcMRI group, increased connectivity in bilateral motor cortex following MST training correlated with this next-day improvement. This increased connectivity did not appear to reflect initial learning since it did not correlate with learning during training and was not greater after MST training than MCT performance. Instead, we hypothesize that this increased connectivity processed the new memories for sleep-dependent consolidation. Our findings demonstrate that physiological processes immediately after learning correlate with sleep-dependent performance improvement and suggest that the wakeful resting brain prepares memories of recent experiences for later consolidation during sleep.
authors.affiliation: Harvard Medical School, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA; Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Gregory
authors.affiliation: Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA; Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School, Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129, USA.
authors.forename: Yigal
authors.initials: Y
authors.lastname: Agam
authors.affiliation: Harvard Medical School, Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129, USA.
authors.forename: Chindhuri
authors.initials: C
authors.lastname: Selvadurai
authors.affiliation: Harvard College, Cambridge, MA 02138, USA.
authors.forename: Amanda
authors.initials: A
authors.lastname: Nagy
authors.affiliation: Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Vangel
authors.affiliation: Harvard Medical School, Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Tucker
authors.affiliation: Harvard Medical School, Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Edwin M
authors.initials: EM
authors.lastname: Robertson
authors.affiliation: Harvard Medical School, Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA; Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Stickgold
authors.affiliation: Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA; Harvard Medical School, Boston, MA 02115, USA; Harvard Medical School, Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129, USA. Electronic address: dara@nmr.mgh.harvard.edu.
authors.forename: Dara S
authors.initials: DS
authors.lastname: Manoach
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D005385:Fingers; D006801:Humans; D007858:Learning / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D009043:Motor Activity; D009044:Motor Cortex / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D012146:Rest; D012890:Sleep / Q000502:physiology*; D055815:Young Adult
keywords: Functional connectivity MRI; Memory consolidation; Motor learning; Procedural memory; Resting state; Sleep