For over a decade my research career as a systems neuroscientist has been centered around measuring the brain in different states of consciousness using electrophysiology. Two ways to study conscious transitions empirically are by investigating the brain during sleep and while under anesthesia. I spent my doctoral and early postdoctoral work studying how sleep improves learning and memory at the neural network level. I characterized a phenomenon known as replay (when networks in the brain rehearse previous experiences offline) in a novel visual area. I continued research on replay in my early postdoctoral work in the hippocampus (an area important for spatial navigation as well as memory formation). My work centered around trying to understand how different hippocampal replay trajectories are selected by reward centers in the brain for future behavioral action. 

I am now interested in studying the brain activity associated with anesthetics to broaden my understanding of brain states that exhibit altered consciousness. In fact, the brain shares similar electrophysiological activity during sleep with some anesthetic transitions. With anesthetics, though one is able to compare how different anesthetic agents interact with different neuromodulatory systems to cause similar behavior outcomes (i.e. sedation and unconsciousness). My current project is to explore and evaluate different computational approaches to quantifying anesthetic depth using electroencephalography. A thorough characterization of the brain activity associated with loss of consciousness during anesthesia is of critical importance to better monitor patients undergoing anesthesia. I am excited by this new opportunity to meld my previous expertise in systems neuroscience electrophysiology with clinical and translational work. It has been a long-term aspiration of mine to do research that will have direct applications to improving human health. 

Honors & Awards

  • Helena Anna Henzl Gabor Young Women in Science Fund Travel Grant, Stanford University (2019)
  • Dean's Postdoctoral Fellowship Award, Stanford University (2018)
  • Anesthesia Training Program in Biomedical Research T32, Department of Anesthesiology, Stanford School of Medicine (2018)
  • President's Research Scholarship Award, UT Health Science Center Houston (2014)
  • Dean’s Research Scholarship Award, UT Health Science Center Houston (2013)
  • Roberta M. and Jean M. Worsham Endowed Scholarship, UT Health Science Center Houston (2012)
  • Tzu-Chi Foundation Scholarship for Excellence, UT Health Science Center Houston (2012)
  • Eka Francian Chemistry Honor Society, Ripon College (2007)
  • Beta Beta Beta Biological Honor Society, Ripon College (2006-2007)
  • The Laurel Honor Society, Ripon College (2006)
  • Psi Chi National Honor Society in Psychology, Ripon College (2005 - 2007)

Boards, Advisory Committees, Professional Organizations

  • Member, International Anesthesia Research Society (2017 - Present)
  • Member, Society for Neuroscience (2008 - Present)
  • Family Committee Chair, SURPAS Stanford University Postdoctoral Association (2017 - Present)
  • Student Member, Association for the Scientific Study of Consciousness (2007 - 2011)
  • Student Member, Mind Science Foundation (2007 - 2011)
  • Chapter President, Psi Chi National Honor Society in Psychology (2006 - 2007)
  • Member, Psi Chi National Honor Society in Psychology (2005 - Present)

Professional Education

  • Bachelor of Arts, Ripon College (2007)
  • Doctor of Philosophy, Univ Texas Health Science Ctr-Houston (2014)

All Publications

  • Remifentanil and Nitrous Oxide Anesthesia Produces a Unique Pattern of EEG Activity During Loss and Recovery of Response FRONTIERS IN HUMAN NEUROSCIENCE Eagleman, S. L., Drover, C. M., Drover, D. R., Ouellette, N. T., MacIver, M. 2018; 12: 173


    Nitrous oxide (N2O) and remifentanil (remi) are used along with other anesthetic and adjuvant agents for routine surgical anesthesia, yet the electroencephalogram (EEG) changes produced by this combination are poorly described. N2O administered alone produces EEG spectral characteristics that are distinct from most hypnotics. Furthermore, EEG frequency-derived trends before and after clinically relevant time points vary depending on N2O concentration. Remifentanil typically increases low frequency and decreases high frequency activity in the EEG, but how it influences N2O's EEG effect is not known. Previous attempts to characterize EEG signals of patients anesthetized with N2O using frequency-derived measures have shown conflicts and inconsistencies. Thus, in addition to determining the spectral characteristics of this unique combination, we also test whether a newly proposed characterization of time-delayed embeddings of the EEG signal tracks loss and recovery of consciousness significantly at clinically relevant time points. We retrospectively investigated the effects of remi and N2O on EEG signals recorded from 32 surgical patients receiving anesthesia for elective abdominal surgeries. Remifentanil and N2O (66%) were co-administered during the procedures. Patients were tested for loss and recovery of response (ROR) to verbal stimuli after induction and upon cessation of anesthesia, respectively. We found that the addition of remifentanil to N2O anesthesia improves the ability of traditional frequency-derived measures, including the Bispectral Index (BIS), to discriminate between loss and ROR. Finally, we found that a novel analysis of EEG using nonlinear dynamics showed more significant differences between states than most spectral measures.

    View details for DOI 10.3389/fnhum.2018.00173

    View details for Web of Science ID 000431524500001

    View details for PubMedID 29867405

    View details for PubMedCentralID PMC5950731

  • Can you hear me now? Information processing in primary auditory cortex at loss of consciousness British Journal of Anaesthesia Eagleman, S. L., MacIver, M. B. 2018; 121 (3): 526-529
  • Do complexity measures of frontal EEG distinguish loss of consciousness in geriatric patients under anesthesia? Frontiers in Neuroscience Eagleman*, S. L., Vaughn*, D. A., Drover, D. R., Drover, C. M., Cohen, M. S., Ouellette, N. T., MacIver, B. 2018

    View details for DOI 10.3389/fnins.2018.00645

  • Calculations of Consciousness: EEG analyses to determine anesthetic depth. Current Opinion in Anesthesiology Eagleman, S., Drover, D. 2018
  • Sensory coding accuracy and perceptual performance are improved during the desynchronized cortical state Nature Communications Beaman, C., Eagleman, S., Dragoi, V. 2017
  • Image sequence reactivation in awake V4 networks PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Eagleman, S. L., Dragoi, V. 2012; 109 (47): 19450-19455


    In the absence of sensory input, neuronal networks are far from being silent. Whether spontaneous changes in ongoing activity reflect previous sensory experience or stochastic fluctuations in brain activity is not well understood. Here we describe reactivation of stimulus-evoked activity in awake visual cortical networks. We found that continuous exposure to randomly flashed image sequences induces reactivation in macaque V4 cortical networks in the absence of visual stimulation. This reactivation of previously evoked activity is stimulus-specific, occurs only in the same temporal order as the original response, and strengthens with increased stimulus exposures. Importantly, cells exhibiting significant reactivation carry more information about the stimulus than cells that do not reactivate. These results demonstrate a surprising degree of experience-dependent plasticity in visual cortical networks as a result of repeated exposure to unattended information. We suggest that awake reactivation in visual cortex may underlie perceptual learning by passive stimulus exposure.

    View details for DOI 10.1073/pnas.1212059109

    View details for Web of Science ID 000311997200085

    View details for PubMedID 23129638

    View details for PubMedCentralID PMC3511092

  • Examining Local Network Processing using Multi-contact Laminar Electrode Recording JOVE-JOURNAL OF VISUALIZED EXPERIMENTS Hansen, B. J., Eagleman, S., Dragoi, V. 2011

    View details for DOI 10.3791/2806

    View details for Web of Science ID 000209222100003

  • Testing pigeon memory in a change detection task PSYCHONOMIC BULLETIN & REVIEW Wright, A. A., Katz, J. S., Magnotti, J., Elmore, L. C., Babb, S., Alwin, S. 2010; 17 (2): 243-249


    Six pigeons were trained in a change detection task with four colors. They were shown two colored circles on a sample array, followed by a test array with the color of one circle changed. The pigeons learned to choose the changed color and transferred their performance to four unfamiliar colors, suggesting that they had learned a generalized concept of color change. They also transferred performance to test delays several times their 50-msec training delay without prior delay training. The accurate delay performance of several seconds suggests that their change detection was memory based, as opposed to a perceptual attentional capture process. These experiments are the first to show that an animal species (pigeons, in this case) can learn a change detection task identical to ones used to test human memory, thereby providing the possibility of directly comparing short-term memory processing across species.

    View details for DOI 10.3758/PBR.17.2.243

    View details for Web of Science ID 000281812500018

    View details for PubMedID 20382927