Research
Research Statement
My research spans three interconnected threads in psycholinguistics, cognitive neuroscience, and computational modeling.
The first thread focuses on aphasia and clinical neuroscience. I use lesion-symptom mapping (LSM) and connected speech analysis to examine whether naming error profiles — rather than overall accuracy — serve as reliable behavioral biomarkers of lesion location in post-stroke aphasia, with an emphasis on cross-task stability across standardized assessments.
The second thread develops computational models of language in neurological populations by systematically perturbing the internal architecture of large language models to simulate discourse-level changes associated with conditions such as aphasia and mild cognitive impairment (MCI). This work bridges clinical and computational approaches, using behavioral and cognitive data to validate model behavior against real patient profiles — including data from the Aging Brain Cohort at the University of South Carolina (ABC@UofSC).
The third thread — and the focus of my dissertation — investigates spatial cognition and auditory source tracking during language comprehension, specifically how listeners form and update mental models of where voices and sounds originate in space, and how those spatial representations interact with linguistic reference and discourse structure.
Current Projects
Spatial Memory of Auditory Sources in Language Comprehension
This project investigates how people encode and retain information about the spatial locations of auditory sources while comprehending spoken language. Using behavioral and neuroimaging paradigms, I examine the degree to which spatial context — specifically where a voice or sound originates in space — is integrated into the mental models listeners construct during discourse processing.
Results were presented at Human Sentence Processing 2026 (Cambridge, MA), Psychonomics 2025 (Denver, CO), and the Graduate Students in Linguistics Student Research Symposium 2025 (Columbia, SC), in collaboration with Dr. Amit Almor.
Error Profiles as Behavioral Biomarkers of Lesion Location
This project examines the cross-task stability of naming error profiles across the Philadelphia Naming Test (PNT) and Western Aphasia Battery-Revised (WAB-R) using lesion-symptom mapping (LSM). The goal is to establish whether error profile distributions — rather than overall accuracy — serve as reliable behavioral biomarkers of lesion location in post-stroke aphasia. Manuscript in preparation with co-authors Roger Newman-Norlund, Saeed Ahmadi, Nadra Salman, Yong Yang, Regan Willis, Xiang Guan, and Julius Fridriksson.
LLM Perturbation Modeling of Cognitive Decline
This project develops a computational framework for modeling mild cognitive impairment (MCI) by systematically perturbing the internal architecture of large language models (e.g., attention heads, MLP layers, residual stream). Perturbation-induced changes in discourse output are validated against linguistic and cognitive data from the Aging Brain Cohort at the University of South Carolina (ABC@UofSC) across three discourse genres: picture description, story retelling, and procedural discourse. The project treats MoCA scores as a continuous cognitive dimension rather than a categorical MCI label.
Reference Processing Modulation During HD-tDCS
In collaboration with Sarah Wilson, Samantha Langley, Dirk-Bart den Ouden, and Amit Almor, this project examined how high-definition transcranial direct current stimulation (HD-tDCS) of the superior parietal cortex modulates linguistic reference processing during reading comprehension (Wilson, Langley, Warren, den Ouden, & Almor, in prep). Findings were presented at the Society for the Neurobiology of Language (2023, Marseille).
StatTeacher Toolkit
Drawing on my experience teaching introductory and methods courses in psychology as Instructor of Record, the StatTeacher Toolkit is an interactive application designed to help statistics instructors and students engage with core statistical concepts through live visualization and simulation.
Publications & Presentations
Journal Articles
Warren, K., Nichols, C., Petersen, D., et al. (2025). Stylistic language drives perceived moral superiority of LLMs. Scientific Reports, 15, 39168. https://doi.org/10.1038/s41598-025-25046-9
Preprints & Submitted Manuscripts
Fridriksson, J., Newman-Norlund, R. D., Ahmadi, S., Willis, R., Salman, N., Warren, K., et al. (2026). Stroke lesions as a Rosetta Stone for language model interpretability. arXiv preprint arXiv:2602.04074. https://arxiv.org/abs/2602.04074
Visikamalla, H., Riccardi, N., Rangus, I., Warren, K., Nichols, C., Horacek, K., Newman-Norlund, S., Fridriksson, J., & Bonilha, L. (Submitted 3/23/26). Tip-of-the-Tongue Word-Finding Phenomenon: The Significance of the White Matter Language Network. Neurobiology of Language.
Warren, K. (Submitted 3/19/26). StatTeacher Toolkit: A Browser-Based Application for Generating and Practicing Psychological Statistics Problems. The Journal of Open Source Education.
Manuscripts in Preparation
Warren, K., Newman-Norlund, R., Ahmadi, S., Salman, N., Yang, Y., Willis, R., Guan, X., & Fridriksson, J. (in prep). Error Profiles as Behavioral Biomarkers of Lesion Location: Cross-Task Stability and Anatomical Predictability of Naming Error Types in Chronic Aphasia.
Warren, K. & Almor, A. (in prep). Hearing Where They Were: Spatial Indexing as a Modality-General Discourse Mechanism.
Wilson, S. C., Langley, S., Warren, K., den Ouden, D. B., & Almor, A. (in prep). Transcranial Direct Current Stimulation of the Superior Parietal Cortex Modulates Reference Processing during Reading Comprehension.
Conference Presentations
Warren, K. & Almor, A. (2026, March 27). Spatial memory of auditory sources in language comprehension [Poster]. Human Sentence Processing 2026 (HSP), Cambridge, MA.
Warren, K. & Almor, A. (2025, November 22). Spatial memory of auditory sources in language comprehension [Poster]. Psychonomics, Denver, CO.
Warren, K. & Almor, A. (2025, November 15). Spatial memory of auditory sources in language comprehension [Presentation]. Graduate Students in Linguistics Student Research Symposium, Columbia, SC.
Wilson, S. C., Langley, S., Warren, K., den Ouden, D., & Almor, A. (2023, October 25). Reference processing modulation during HD-transcranial direct current stimulation [Poster]. Society for the Neurobiology of Language, Marseille, France.
Warren, K., Bury, H., & Weist, M. D. (2022). Comparing clinicians' and graduate students' multicultural knowledge and awareness in school psychology and clinical community programs at the University of South Carolina [Poster]. Southeastern School Behavioral Health Conference, Myrtle Beach, SC.
Che, B. & Warren, K. (2020). Air cleaning drone feasibility: Designing a mobile filtration unit to reduce indoor particulate matter [Poster]. South Carolina Junior Academy of Science. https://scholarexchange.furman.edu/scjas/2020/all/140