Bio


Ph.D. candidate in Electrical Engineering
Member of the Brain Interfacing Laboratory (BIL)

Honors & Awards


  • Graduate Research Fellowship, National Science Foundation (2017)
  • Firestone Medal for Excellence in Undergraduate Research, Stanford University (June 2017)

Professional Affiliations and Activities


  • Outreach Coordinator, Women in Electrical Engineering (2015 - Present)
  • President and Founding Member, Fuse Electrical Engineering Student Group (2014 - 2017)
  • Member of the Education Area Steering Group, Stanford Long Range Planning (2017 - 2017)
  • Committee Member, Electrical Engineering Student Life Committee (2015 - 2016)

Education & Certifications


  • BS, Stanford University, Electrical Engineering (2017)

Stanford Advisors


Lab Affiliations


Work Experience


  • Undergraduate Researcher, Stanford Neural Prosthetics Systems Laboratory (June 2016 - June 2017)

    My project is to analyze the link between neural signals recorded from small populations of neurons in the premotor cortex and the behavior of nonhuman primates in a decision making task. The goal of the project is to test the hypothesis that specific activity before the onset of a sensory stimulus modifies the processing of the stimulus and subsequent behavior, such as reaction time.

    Location

    Stanford, CA

  • Research and Development Intern, Sandia National Laboratories (June 2015 - April 2016)

    • Led the creation of a hybrid object recognition system for X-ray radiographs
    • First author and presented paper at the SPIE Optics and Photonics conference in August 2015
    • Contributed to data collection and analysis

    Location

    Albuquerque, NM

  • Technical Intern, Sandia National Laboratories (June 2014 - September 2014)

    • Led the testing of a signal recognition algorithm (Multinomial Pattern Matching) on a novel signal type
    • Created templates and models for image-based automatic target recognition using MATLAB
    • Designed and assisted in data collection

    Location

    Albuquerque, NM

  • Research Associate, The Mind Research Network (May 2013 - July 2013)

    • Presented poster-paper for project to evaluate the effectiveness of low power POEMS (pulsed oscillatory electromagnetic stimulation) in altering excitability in the brain at the 19th Annual Meeting for the Organization for Human Brain Mapping

    Location

    Albuquerque, NM

  • Intern, Southwest Neurosurgical Associates (April 2013 - May 2013)

    • Shadowed Dr. Andrew Metzger, a private practice neurosurgeon, as a senior project
    • Attended many surgeries and gamma knife radiation planning sessions
    • Grew accustomed to reading MRI scans, X-ray films, and CT scans

    Location

    Albuquerque, NM

All Publications


  • Frequency shifts and depth dependence of premotor beta band activity during perceptual decision-making. The Journal of neuroscience : the official journal of the Society for Neuroscience Chandrasekaran, C., Bray, I. E., Shenoy, K. V. 2019

    Abstract

    Neural activity in the premotor and motor cortices shows prominent structure in the beta frequency range (13-30 Hz). Currently, the behavioral relevance of this beta band activity (BBA) is debated. The underlying source of motor BBA and how it changes as a function of cortical depth is also not completely understood. Here, we addressed these unresolved questions by investigating BBA recorded using laminar electrodes in the dorsal premotor cortex (PMd) of two male rhesus macaques performing a visual reaction time (RT) reach discrimination task. We observed robust BBA before and after the onset of the visual stimulus but not during the arm movement. While post-stimulus BBA was positively correlated with RT throughout the beta frequency range, pre-stimulus correlation varied by frequency. Low beta frequencies (12 to 20 Hz) were positively correlated with RT and high beta frequencies (22 to 30 Hz) were negatively correlated with RT. Analysis and simulations suggested that these frequency-dependent correlations could emerge due to a shift in the component frequencies of the pre-stimulus BBA as a function of RT, such that faster RTs are accompanied by greater power in high beta frequencies. We also observed a laminar dependence of BBA, with deeper electrodes demonstrating stronger power in low beta frequencies both pre- and post-stimulus. The heterogeneous nature of BBA and the changing relationship between BBA and RT in different task epochs may be a sign of the differential network dynamics involved in cue expectation, decision-making, motor preparation, and movement execution.SIGNIFICANCE STATEMENTBeta band activity (BBA) has been implicated in motor tasks, in disease states, and as a potential signal for brain-machine interfaces. However, the behavioral relevance of BBA and its laminar organization in premotor cortex have not been completely elucidated. Here we addressed these unresolved issues using simultaneous recordings from multiple cortical layers of the premotor cortex of monkeys performing a decision-making task. Our key finding is that BBA is not a monolithic signal. Instead, BBA consists of at least two frequency bands. The relationship between BBA and eventual behavior, such as reaction time, also dynamically changes depending on task epoch. We also provide further evidence that BBA is laminarly organized, with greater power in deeper electrodes for low beta frequencies.

    View details for PubMedID 30606756

  • Exploration of available feature detection and identification systems and their performance on radiographs Wantuch, A. C., Vita, J. A., Jimenez, E. S., Bray, I. E., Grim, G. P., Barber, H. B., Furenlid, L. R. SPIE-INT SOC OPTICAL ENGINEERING. 2016

    View details for DOI 10.1117/12.2237211

    View details for Web of Science ID 000389379500006

  • Hybrid object detection system for X-ray radiographs Vita, J. A., Wantuch, A. C., Jimenez, E. S., Bray, I. E., Grim, G. P., Barber, H. B., Furenlid, L. R. SPIE-INT SOC OPTICAL ENGINEERING. 2016

    View details for DOI 10.1117/12.2237213

    View details for Web of Science ID 000389379500008

  • Exploring the feasibility of traditional image querying tasks for industrial radiographs Bray, I. E., Tsai, S. J., Jimenez, E. S., Barber, H. B., Furenlid, L. R., Roehrig, H. N. SPIE-INT SOC OPTICAL ENGINEERING. 2015

    View details for DOI 10.1117/12.2195585

    View details for Web of Science ID 000366389300002