Curriculum Vitae

2023 - Present  [ University of Iowa ] [ Ph.D. (in progress) ]

Dissertation: Spatial and temporal dynamics underlying the integration of task representations

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2021 - 2023  [ University of Iowa ] [ Master of Arts in Psychology ]

First Year Project: Mapping representational integration for hierarchical cognitive control

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2014 - 2018  [ NDSU ] [ Bachelor of Science in Psychology ]

Minors in Zoology & Neuroscience; summa cum laude, GPA 3.98

2026

1. Leach, S. C., Stokes, S. E., Morrow, H., Jiang, J., & Hwang, K. (in prep). Integrated uncertainty modulates frontoparietal hub connectivity for adaptive control.

2. Leach, S. C., Chen, X., & Hwang, K. (under review). Hierarchical Representation of neurocognitive task set representations mediates cognitive flexibility. https://doi.org/10.64898/2026.01.20.700694 

2024 - 2025

3. Leach, S. C., Morrow, H., Jiang, J., & Hwang, K. (2025). Frontoparietal Hubs leverage probabilistic representations and integrated uncertainty to guide cognitive flexibility. Journal of Neuroscience, 45(49) 10.1523/JNEUROSCI.0989-25.2025

4.     Chen, X., Leach, S. C., Hollis, J., Cellier, D., & Hwang, K. (2024). The thalamus encodes and updates context representations during hierarchical cognitive control. PLoS Biology, 22(12), e3002937 https://doi.org/10.1371/journal.pbio.3002937 

5. Hernandez, A., Sania, A., Bowers, M. E., Leach, S. C., Mcsweeney, M., Yoder, L., ... & Morales, S. (2024). Examining the impact of prenatal maternal internalizing symptoms and socioeconomic status on children's frontal alpha asymmetry and psychopathology. Developmental Psychobiology, 66(3), e22476.

6. Morales, S., Bowers, M. E., Shuffrey, L., Ziegler, K., Troller-Renfree, S., Hernandez, A., Leach, S. C., ... & Elliott, A. J. (2024). Maternal education prospectively predicts child neurocognitive function: An environmental influences on child health outcomes study. Developmental Psychology.

7. Xu, X., Buzzell, G. A., Bowers, M. E., Shuffrey, L. C., Leach, S. C., McSweeney, M., ... & Morales, S. (2024). Electrophysiological correlates of inhibitory control in children: Relations with prenatal maternal risk factors and child psychopathology. Development and Psychopathology, 1-14.

2022 - 2023

8. Morales, S., Bowers, M. E., Leach, S. C., Buzzell, G. A., Mcsweeney, M., Yoder, L., Fifer, W., Elliott, A., Fox, N. A. (2023). Development of auditory change-detection and attentional capture, and their relation to inhibitory control. Psychophysiology, 60(4), e14211.

9. Isler, J. R., Pini, N., Lucchini, M., Shuffrey, L. C., Morales, S., Bowers, M. E., Leach, S. C., Sania, A., Wang, L., Condon, C., Nugent, J. D., Elliott, A. J., Friedrich, C., Andrew, R., Fox, N. A., Myers, M. M., & Fifer, W. P. (2023). Longitudinal characterization of EEG power spectra during eyes open and eyes closed conditions in children. Psychophysiology, 60, e14158.

10.  Lopez, K., Monachino, A., Morales, S., Leach, S. C., Bowers, M.E., Gabard-Durnam, L. J. (2022). HAPPILEE: HAPPE in Low Electrode Encephalography, a standardized preprocessing software for lower density recordings. NeuroImage, 260, 119390.

11.  Morales, S., Bowers, M. E., Leach, S. C., Buzzell, G. A., Fifer, W., Elliott, A., & Fox, N. A. (2022). Time-frequency dynamics of error monitoring in childhood: An EEG study. Developmental Psychobiology, 64(3), e22215.

2018 - 2021

12.  Troller-Renfree, S.V., Morales, S., Leach, S.C., Bowers, M.E., Debnath, R., Fifer, W.P., Fox, N.A., & Noble, K.G. (2021). Feasibility of assessing brain activity using mobile, in-home collection of electroencephalography: methods and analysis. Developmental Psychobiology.

13.  Leach, S. C., Morales, S., Bowers, M. E., Buzzell, G. A., Debnath, R., Beall, D., & Fox, N. A. (2020). Adjusting ADJUST: Optimizing the ADJUST algorithm for pediatric data using geodesic nets. Psychophysiology, 57(8), e13566.

14.  Debnath, R., Buzzell, G. A., Morales, S., Bowers, M. E., Leach, S. C., & Fox, N. A. (2020). The Maryland analysis of developmental EEG (MADE) pipeline. Psychophysiology, 57(6), e13580.

15.  Leach, S. C. & Conwell, E. (2018). The use of acoustic information in lexical ambiguity resolution: An event related potential study. NeuroReport, 29(16), 1379-1383.

2021 - Present  [ Graduate Research Assistant ]  [ University of Iowa ]  

• Investigated neural correlates of hierarchical task representations for a first-year project.

  • representational similarity analyses (RSA)

  • Chen, X., Leach, S. C., Hollis, J., Cellier, D., & Hwang, K. (2024). The thalamus encodes and updates context representations during hierarchical cognitive control. PLoS biology, 22(12), e3002937.

• Investigating neurocognitive processes underlying the integration of task relevant information (spatial and temporal dynamics) for dissertation project.

  • parametric modulation, binary and probabilistic decoding, time-frequency, RSA, computational modeling (Bayesian), linear and mixed effects regressions, and functional connectivity

  • Leach, S. C., Hollow, H., Jiang, J., & Hwang, K. (2025). Frontoparietal hubs leverage probabilistic representations and integrated uncertainty to guide cognitive flexibility. Journal of Neuroscience, 45(49).

  • Leach, S. C., Stokes, S. E., Hollow, H., Jiang, J., & Hwang, K. (in prep). Integrated uncertainty modulates frontoparietal hub connectivity for adaptive control.

• Investigated how the underlying neural representations of hierarchical representation structures interact with the perceptual system to drive observed switch costs.

  • RSA, decoding, linear and mixed effects regressions

  • Leach, S. C., Chen, X., & Hwang, K. (under review). Hierarchical Representation of neurocognitive task set representations mediates cognitive flexibility.

• Collaborated with Dr. Jiefeng Jiang on an EEG project (designed task; collected and preprocessed data).

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2018 - 2021  [ Research Assistant ]  [ U of Maryland, College Park ]

• Worked primarily on a longitudinal, multi-site project utilizing EEG to explore environmental and child health outcomes as well as a longitudinal project investigating physiological (ECG and EEG) correlates of temperament from infancy to adulthood.

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2015 - 2018  [ Undergraduate Research Assistant ]  [ NDSU ] 

• Investigated the psychological and neural systems underlying visual working memory and attention in young adults by utilizing behavioral, EEG, and transcranial magnetic stimulation (TMS) methods.

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2016 - 2018  [ Undergraduate Research Assistant ]  [ NDSU ] 

• Investigated how children generalize sentence structure knowledge in novel situations and learn homophones, how adults process homophones, and conducted an honors thesis project: 

  • Leach, S. C. & Conwell, E. (2018). The use of acoustic information in lexical ambiguity resolution: An event related potential study. NeuroReport, 29(16), 1379-1383.

[ Spring 2026 ]  [ TA for Neuroscience of Executive Functions ]

[Professor: Dr. Kai Hwang]  [ University of Iowa, Iowa City, IA ]

• Graded exams, held office hours, did 2 guest lectures

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[ Fall 2024 ]  [ TA for Intro to Cognitive Neuroscience ]

[Professor: Dr. Eliot Hazeltine]  [ University of Iowa, Iowa City, IA ]

• Graded essays, held office hours, did a guest lecture

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[ Spring 2024 ]  [ TA for Neuroscience of Executive Functions ]

[Professor: Dr. Kai Hwang]  [ University of Iowa, Iowa City, IA ]

• Graded exams, held office hours, did a guest lecture, took notes for SDS students

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[ Fall 2018 ]  [ TA for Introductory Psychology ]

[Professor: Dr. David Wittrock]  [ NDSU, Fargo, ND ]

• Graded weekly online exams

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[ Fall 2017 ]  [ TA for Memory & Knowledge ]

[Professor: Dr. David Wittrock]  [ NDSU, Fargo, ND ]

• Graded homework assignments and exams

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[ Fall 2016 ]  [ TA for Research Methods 1 ]

[Professor: Dr. David Wittrock]  [ NDSU, Fargo, ND ]

• Graded homework, ran in-class activities, created practice problems for review sheets and hosted review sessions

• Physiological Recording Equipment 

  • EEG data collection systems: EGI (Net Station 4 & 5), Biosemi (ActiveTwo & ActiveThree), Brain Vision

• Computational Modeling

  • Bayesian model (see https://doi.org/10.1523/JNEUROSCI.0989-25.2025)

• Programming & Data Analysis Software Skills

  • MATLAB (psych toolbox & EEGLAB)

  • Python (+ PsychoPy3)

  • R (R Studio)

  • AFNI

  • Bash

  • E-prime

  • SPSS Statistical Software; JASP statistical Software

  • Java (NetBeans IDE)