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SLEEP AND RESILIENCE

Sleep and Resilience

Together with the Walter Reed Army Institute of Research, we are developing individual-specific phenomenological models to predict the effects of total sleep deprivation and chronic sleep restriction on human alertness and performance. In addition, we are exploring how best to incorporate the effects of performance-restoring countermeasures, such as naps and caffeine, into these models. Moreover, we are attempting to develop analytic tools to categorize distinct sleep-loss phenotypes and associations between resilience to sleep loss and stress markers, such as cortisol.

Software

Publications

Reifman, J., N. V. Priezjev, and F. G. Vital-Lopez. Can we rely on wearable sleep-tracker devices for fatigue management? Sleep. 2024 March 11; 47(3):zsad288. [PDF, Pubmed]

Vital-Lopez, F. G., T. J. Doty, I. Anlap, W. D. S. Killgore, and J. Reifman. 2B-Alert App 2.0: personalized caffeine recommendations for optimal alertness. Sleep. 2023 July 11; 46(7):zsad080. [PDF, Pubmed]

Priezjev, N. V., F. G. Vital-Lopez, and J. Reifman. Assessment of the unified model of performance: accuracy of group-average and individualised alertness predictions. Journal of Sleep Research. 2023 April; 32(2):e13626. [PDF, Pubmed]

Reifman, J., K. Kumar, L. Hartman, A. Frock, T. J. Doty, T. J. Balkin, S. Ramakrishnan, and F. G. Vital-Lopez. 2B-Alert Web 2.0, an open-access tool for predicting alertness and optimizing the benefits of caffeine: utility study. Journal of Medical Internet Research. 2022 January 27; 24(1):e29595. [PDF, PubMed]

Vital-Lopez, F. G., T. J. Doty, and J. Reifman. Optimal sleep and work schedules to maximize alertness. Sleep. 2021 November 12; 44(11):zsab144. [PDF, PubMed]

LaGoy, A. D., M. Sphar, C. Connaboy, M. N. Dretsch, F. Ferrarelli, S. Laxminarayan, S. Ramakrishnan, C. Wang, J. Reifman, and A. Germain. Individuals with and without military-related PTSD differ in subjective sleepiness and alertness but not objective sleepiness. Journal of Psychiatric Research. 2021 September; 141:301-308. [PDF, PubMed]

Vital-Lopez, F. G., T. J. Balkin, and J. Reifman. Models for predicting sleep latency and sleep duration. Sleep. 2021 May 14; 44(5):zsaa263. [PDF, PubMed]

Laxminarayan, S., C. Wang, T. Oyama, J. D. Cashmere, A. Germain, and J. Reifman. Identification of Veterans with PTSD based on EEG features collected during sleep. Frontiers in Psychiatry. 2020 October 30; 11:532623. [PDF, PubMed]

Wang, C., S. Laxminarayan, S. Ramakrishnan, A. Dovzhenok, J. D. Cashmere, A. Germain, and J. Reifman. Increased oscillatory frequency of sleep spindles in combat-exposed Veteran men with post-traumatic stress disorder. Sleep. 2020 October 13; 43(10):zsaa064. [PDF, PubMed]

Wang, C., S. Laxminarayan, J. David Cashmere, A. Germain, and J. Reifman. Inter-channel phase differences during sleep spindles are altered in Veterans with PTSD. NeuroImage: Clinical. 2020 August 20; 28:102390. [PDF, PubMed]

Laxminarayan, S., C. Wang, S. Ramakrishnan, T. Oyama, J. D. Cashmere, A. Germain, and J. Reifman. Alterations in sleep electroencephalography synchrony in combat-exposed Veterans with post-traumatic stress disorder. Sleep. 2020 July 13; 43(7):102390. [PDF, PubMed]

Wang, C., S. Ramakrishnan, S. Laxminarayan, A. Dovzhenok, J. D. Cashmere, A. Germain, and J. Reifman. An attempt to identify reproducible high-density EEG markers of PTSD during sleep. Sleep. 2020 January 13; 43(1):zsz207. [PDF, PubMed]

Ferrarelli, F., R. Kaskie, S. Laxminarayan, S. Ramakrishnan, J. Reifman, and A. Germain. An increase in sleep slow waves predicts better working memory performance in healthy individuals. Neuroimage. 2019 May 1; 191:1-9. [PDF, PubMed]

Reifman, J., S. Ramakrishnan, J. Liu, A. Kapela, T. J. Doty, T. J. Balkin, K. Kumar, and M. Y. Khitrov. 2B-Alert App: a mobile application for real-time individualized prediction of alertness. Journal of Sleep Research. 2019 April; 28(2):e12725. [PDF, PubMed]

Hansen, D. A., S. Ramakrishnan, B. C. Satterfield, N. J. Wesensten, M. E. Layton, J. Reifman, and H. P. A. Van Dongen. Randomized, double-blind, placebo-controlled, crossover study of the effects of repeated-dose caffeine on neurobehavioral performance during 48 h of total sleep deprivation. Psychopharmacology (Berl). 2019 April; 236(4):1313-1322. [PDF, PubMed]

Vital-Lopez, F. G., S. Ramakrishnan, T. J. Doty, T. J. Balkin, and J. Reifman. Caffeine dosing strategies to optimize alertness during sleep loss. Journal of Sleep Research. 2018 October; 27(5):e12711. [PDF, PubMed]

Reifman, J., K. Kumar, M. Y. Khitrov, J. Liu, and S. Ramakrishnan. PC-PVT 2.0: an updated platform for psychomotor vigilance task testing, analysis, prediction, and visualization. Journal of Neuroscience Methods. 2018 July 1; 304:39-45. [PDF, PubMed]

Liu, J., S. Ramakrishnan, S. Laxminarayan, M. Neal, D. J. Cashmere, A. Germain, and J. Reifman. Effects of signal artefacts on electroencephalography spectral power during sleep: quantifying the effectiveness of automated artefact-rejection algorithms. Journal of Sleep Research. 2018 February; 27(1):98-102. [PDF, PubMed]

Liu, J., S. Ramakrishnan, S. Laxminarayan, T. J. Balkin, and J. Reifman. Real-time individualization of the unified model of performance. Journal of Sleep Research. 2017 December; 26(6):820-831. [PDF, PubMed]

Reifman, J., K. Kumar, N. J. Wesensten, N. A. Tountas, T. J. Balkin, and S. Ramakrishnan. 2B-Alert Web: an open-access tool for predicting the effects of sleep/wake schedules and caffeine consumption on neurobehavioral performance. Sleep. 2016 December 1; 39(12):2157-2159. [PDF, PubMed]

Ramakrishnan, S., N. J. Wesensten, G. H. Kamimori, J. E. Moon, T. J. Balkin, and J. Reifman. A unified model of performance for predicting the effects of sleep and caffeine. Sleep. 2016 October 1; 39(10):1827-1841. [PDF, PubMed]

Ramakrishnan, S., N. J. Wesensten, T. J. Balkin, and J. Reifman. A unified model of performance: validation of its predictions across different sleep/wake schedules. Sleep. 2016 January 1; 39(1):249-262. [PDF, PubMed]

Ramakrishnan, S., S. Laxminarayan, N. J. Wesensten, T. J. Balkin, and J. Reifman. Can we predict cognitive performance decrements due to sleep loss and the recuperative effects of caffeine? Proceedings of the HFM-254 Symposium on Health Surveillance and Informatics in Missions: Multidisciplinary Approaches and Perspectives. Paris, France. 2015 October 12-14; 20:1-20. [PDF, DTIC]

Ramakrishnan, S., W. Lu, S. Laxminarayan, N. J. Wesensten, T. L. Rupp, T. J. Balkin, and J. Reifman. Can a mathematical model predict an individual's trait-like response to both total and partial sleep loss? Journal of Sleep Research. 2015 June; 24(3):262-269. [PDF, PubMed]

Ramakrishnan, S., S. Laxminarayan, N. J. Wesensten, G. H. Kamimori, T. J. Balkin, and J. Reifman. Dose-dependent model of caffeine effects on human vigilance during total sleep deprivation. Journal of Theoretical Biology. 2014 October 7; 358:11-24. [PDF, PubMed]

Khitrov, M. Y., S. Laxminarayan, D. Thorsley, S. Ramakrishnan, S. Rajaraman, N. J. Wesensten, and J. Reifman. PC-PVT: a platform for psychomotor vigilance task testing, analysis, and prediction. Behavior Research Methods. 2014 March; 46(1):140-147. [PDF, PubMed]

Rajdev, P., D. Thorsley, S. Rajaraman, T. L. Rupp, N. J. Wesensten, T. J. Balkin, and J. Reifman. A unified mathematical model to quantify performance impairment for both chronic sleep restriction and total sleep deprivation. Journal of Theoretical Biology. 2013 April 24; 331:66-77. [PDF, PubMed]

Ramakrishnan, S., S. Rajaraman, S. Laxminarayan, N. J. Wesensten, G. H. Kamimori, T. J. Balkin, and J. Reifman. A biomathematical model of the restoring effects of caffeine on cognitive performance during sleep deprivation. Journal of Theoretical Biology. 2013 February 21; 319:23-33. [PDF, PubMed]

Rajaraman, S., S. Ramakrishnan, D. Thorsley, N. Wesensten, T. Balkin, and J. Reifman. A new metric for quantifying performance impairment on the psychomotor vigilance test. Journal of Sleep Research. 2012 December; 21(6):659-674. [PDF, PubMed]

Thorsley, D., R. Leproult, K. Spiegel, and J. Reifman. A phenomenological model for circadian and sleep allostatic modulation of plasma cortisol concentration. American Journal of Physiology - Endocrinology and Metabolism. 2012 November; 303(10):E1190-1201. [PDF, PubMed]

Ramakrishnan, S., S. Laxminarayan, D. Thorsley, N. J. Wesensten, T. J. Balkin, and J. Reifman. Individualized performance prediction during total sleep deprivation: accounting for trait vulnerability to sleep loss. Proceedings of the 34th IEEE EMBS Annual International Conference. San Diego, CA. 2012 August 28-September 1; 5574-5577. [PDF, PubMed]

Rajaraman, S., N. J. Wesensten, T. J. Balkin, and J. Reifman. Individualized management of fatigue and cognitive performance impairment through biomathematical modeling. Proceedings of the RTO HFM Symposium on Human Performance Enhancement for NATO Military Operations (Science, Technology, and Ethics). Sofia, Bulgaria. 2009 October 5-7; 28:1-11. [PDF, DTIC]

Rajaraman, S., A. V. Gribok, N. J. Wesensten, T. J. Balkin, and J. Reifman. An improved methodology for individualized performance prediction of sleep-deprived individuals with the two-process model. Sleep. 2009 October 1; 32(10):1377-1392. [PDF, PubMed]

Rajaraman, S., A. V. Gribok, N. J. Wesensten, T. J. Balkin, and J. Reifman. Individualized performance prediction of sleep-deprived individuals with the two-process model. Journal of Applied Physiology. 2008 February; 104(2):459-468. [PDF, PubMed]

Reifman, J., S. Rajaraman, and A. V. Gribok. Moving towards individualized performance models. Sleep. 2007 September 1; 30(9):1081-1082. [PDF, PubMed]

Reifman, J., and P. Gander. Commentary on the three-process model of alertness and broader modeling issues. Aviation, Space, and Environmental Medicine. 2004 March; 75(3):A84-88. [PDF, PubMed]

Reifman, J. Alternative methods for modeling fatigue and performance. Aviation, Space, and Environmental Medicine. 2004 March; 75(3):A173-180. [PDF, PubMed]