Our Research

Ayanampudi, V., Kumar, V., Krishnan,.A., Walker, M.P, Ivry, R.B., Knight, R.T.and Gurumoorthy, R.
Personalized transcranial alternating current stimulation improves sleep  quality: initial findings.
Frontiers in Human Neuroscience, doi 10.3389/fnhum.2022.1066453, 2023.

Safety meta-review of transcranial electrical stimulation (tES) studies finds zero serious adverse effects across over 8,000 participants and 18,000 sessions.

Old Brains Come Uncoupled in Sleep: Slow Wave-Spindle Synchrony, Brain Atrophy, and Forgetting. Helfrich, R.F., Mander, B.A., Jagust, W.J, Knight, R.T. and Walker, M. Neuron, 97:1-10, 2018. PMID: 29249289.

Sleep as a potential biomarker of tau and beta-amyloid burden in the human brain. Winer, J.R., Mander, B.A., Helfrich, R.F., Maass, A., Harrison, T.M., Baker, S.L, Knight, R.T., Jagust, W.J. and Walker, M.P. Journal of Neuroscience, doi.org/10.1523/JNEUOSCI.0503-19.2019. PMID: 31209175.

Bidirectional prefrontal-hippocampal dynamics organize information transfer during sleep in humans. Helfrich, R.F., Lendner, J.D., Mander, B.A., Guillen, H., Paff, M., Mnatsakanyan, L., Vadeera, S., Walker, M.P., Lin, J.J. and Knight, R.T. Nature Communications, doi: 10.1038/s41467-019-11444-x, 10(1): 1-16, 2019. PMID: 31395890.

Aperiodic sleep networks promote memory consolidation. Helfrich, R.F., Lendner, J.D. and Knight, R.T. Trends in Cognitive Science, 2175: 1-12, 2021.

Human REM sleep controls neural excitability in support of memory formation. Lendner, J.D., Niethard, N., Mander, B.A., van Schalkwijk, F.J., Schuh-hofer, S., Schmidt, H., Knight, R.T., Born, J., Walker, M.P., Lin, J.J. and Helfrich, R.F. Scientific Advances, doi:10.1126/sciadvj1895, 9:34,1-16, 2023.

Ayanampudi, V., Kumar, V., Krishnan,.A., Walker, M.P, Ivry, R.B., Knight, R.T.and Gurumoorthy, R.
Personalized transcranial alternating current stimulation improves sleep  quality: initial findings.
Frontiers in Human Neuroscience, doi 10.3389/fnhum.2022.1066453, 2023.

Walker, M. P., Brakefield, T., Morgan, A., Hobson, J. A., & Stickgold, R. Practice with sleep makes perfect: sleep-dependent motor skill learning. Neuron, 35(1), 205–211. (2002). https://doi.org/10.1016/s0896-6273(02)00746-8.

Yoo, S.S., Gujar, N., Hu, P., Jolesz, F.A., Walker, M.P. The human emotional brain without sleep—a prefrontal amygdala disconnect. Current Biology, 17 (20), R877-R878; 1531. 2007.

Walker, M.P., Brakefield T., Allan Hobson J., Stickgold, R. Dissociable stages of human memory consolidation and reconsolidation.
Nature, 425 (6958), 616-620; 1447. 2003.

Walker, M.P., Stickgold, R. Sleep, memory, and plasticity. Annu. Rev. Psychol. 57, 139-166; 1353. 2006.

Walker, M.P., Stickgold, R. Sleep-dependent learning and memory consolidation. Neuron 44 (1), 121-133; 1326. 2004.

Walker, M.P., van Der Helm, E. Overnight therapy? The role of sleep in emotional brain processing. Psychological bulletin 135 (5), 731 1264. 2009.

Walker, M.P. The role of sleep in cognition and emotion. Annals of the New York Academy of Sciences 1156 (1), 168-197 1185. 2009.

Perry, E., Walker, M.P., Grace, J., Perry, R. Acetylcholine in mind: a neurotransmitter correlate of consciousness?, Trends in neurosciences 22 (6), 273-280; 1103. 1999.

Krause, A.J., Simon, E.B., Mander, B.A., Greer, S.M., Saletin, J.M., Goldstein, A.N., Walker, M.P. The sleep-deprived human brain. Nature Reviews Neuroscience 18 (7), 404-418; 1007. 2017.

Mander, B.A., Winer, J.R., Walker, M.P. Sleep and human aging. Neuron 94 (1), 19-36 959 2017.

Goldstein, A.N., Walker, M.P. The role of sleep in emotional brain function. Annual review of clinical psychology 10, 679-708 925. 2014.

Stickgold, R., Walker, M.P. Sleep-dependent memory triage: evolving generalization through selective processing. Nature Neuroscience 16 (2), 139-145 779. 2013.

Yoo, S.S., Hu, P.T., Gujar, N., Jolesz, F.A., Walker, M.P. A deficit in the ability to form new human memories without sleep. Nature Neuroscience 10 (3), 385-392. 2007.

Helfrich, R.F., Mander, B.A., Jagust, W.J, Knight, R.T. and Walker, M. Old brains come uncoupled in sleep – slow wave-spindle synchrony, brain atrophy and forgetting.Neuron, 97:1-10, 2018. PMID: 29249289

Winer, J.R., Mander, B.A., Helfrich, R.F., Maass, A., Harrison, T.M., Baker, S.L, Knight, R.T., Jagust, W.J. and Walker, M.P. Sleep as a potential biomarker of tau and beta-amyloid burden in the human brain. Journal of Neuroscience, doi.org/10.1523/JNEUOSCI.0503-19.2019. PMID: 31209175.

Helfrich, R.F., Lendner, J.D., Mander, B.A., Guillen, H., Paff, M., Mnatsakanyan, L.,Vadeera, S., Walker, M.P., Lin, J.J. and Knight, R.T. Bidirectional prefrontal-hippocampal dynamics organize information transfer during sleep in humans.Nature Communications, doi: 10.1038/s41467-019-11444-x, 10(1): 1-16, 2019. PMID: 31395890

Lendner, J.D., Niethard, N., Mander, B.A., van Schalkwijk, F.J., Schuh-hofer, S., Schmidt, H., Knight, R.T., Born, J., Walker, M.P., Lin, J.J. and Helfrich, R.F. Human REM sleep controls neural excitability in support of memory formation. Scientific Advances, doi:10.1126/sciadvj1895, 9:34,1-16, 2023.

Ayanampudi, V., Kumar, V., Krishnan,.A., Walker, M.P, Ivry, R.B., Knight, R.T.and Gurumoorthy, R.
Personalized transcranial alternating current stimulation improves sleep  quality: initial findings.
Frontiers in Human Neuroscience, doi 10.3389/fnhum.2022.1066453, 2023.

Ayanampudi, V., Kumar, V., Krishnan,.A., Walker, M.P, Ivry, R.B., Knight, R.T.and Gurumoorthy, R.
Personalized transcranial alternating current stimulation improves sleep  quality: initial findings.
Frontiers in Human Neuroscience, doi 10.3389/fnhum.2022.1066453, 2023.

Helfrich, R.F., Mander, B.A., Jagust, W.J, Knight, R.T. and Walker, M.
Old brains come uncoupled in sleep – slow wave-spindle synchrony, brain atrophy and forgetting. Neuron, 97:1-10, 2018. PMID: 29249289

Winer, J.R., Mander, B.A., Helfrich, R.F., Maass, A., Harrison, T.M., Baker, S.L, Knight, R.T., Jagust, W.J. and Walker, M.P.
Sleep as a potential biomarker of tau and beta-amyloid burden in the human brain. Journal of Neuroscience, doi.org/10.1523/JNEUOSCI.0503-19.2019, 2019.  PMID: 31209175

Helfrich, R.F., Lendner, J.D., Mander, B.A., Guillen, H., Paff, M., Mnatsakanyan, L.,Vadeera, S., Walker, M.P., Lin, J.J. and Knight, R.T.
Bidirectional prefrontal-hippocampal dynamics organize information transfer during sleep in humans. Nature Communications, doi: 10.1038/s41467-019-11444-x, 10(1): 1-16, 2019. PMID: 31395890

Skelin, I., Zhang, H., Zheng, J., Ma, S., Mander, B.A., Knight, R. T., McNaughton, B.L. and Lin, J.J. 
Coupling between slow-waves and sharp-wave ripples engages distributed neural activity during sleep in humans. Proceedings of the National Academy of Sciences, https://doi.org/10.1073/pnas.2012075118, 118(21) 1-10, 2021. PMID: 34001599

Helfrich, R.F., Lendner, J.D. and Knight, R.T.
Aperiodic sleep networks promote memory consolidation. Trends in Cognitive Science, 2175: 1-12, 2021.

Helfrich, R. and Knight, R.T.
Making memories last: How sleep promotes neuroplasticity. In: Changing Brains- in Honor of Helen Neville,
Routledge Press, Eds:. G. Grossi and A. Newman. 164-180, 2023.

Lendner, J.D., Niethard, N., Mander, B.A., van Schalkwijk, F.J., Schuh-hofer, S., Schmidt, H., Knight, R.T., Born, J., Walker, M.P., Lin, J.J. and Helfrich, R.F.
Human REM sleep controls neural excitability in support of memory formation.
Scientific Advances, doi:10.1126/sciadvj1895, 9:34,1-16, 2023.

Hahn, M.A., Lendner, J.D., Anwander, M., Slama, K.S.J., Knight, R.T., Lin, J.J. and Helfrich, R.F.  A tradeoff between efficiency and robustness in the hippocampal-neocortical memory network during sleep in humans and rodent sleep.
Cell Reports (in review).

Ayanampudi, V., Kumar, V., Krishnan,.A., Walker, M.P, Ivry, R.B., Knight, R.T.and Gurumoorthy, R.
Personalized transcranial alternating current stimulation improves sleep  quality: initial findings.
Frontiers in Human Neuroscience, doi 10.3389/fnhum.2022.1066453, 2023.