Zhivar Sourati

I am Zhivar Sourati, a fifth-year Computer Science Ph.D. candidate at the University of Southern California, advised by Dr. Morteza Dehghani. My research focuses on the reasoning capabilities of language models, particularly how to evaluate and improve their accuracy, robustness, interpretability, and alignment with human behavior. I draw heavily on insights from cognitive science to better ground LLM reasoning in human cognitive processes, including analogical reasoning, case-based reasoning, prototype-based reasoning, and distinctions between System 1 and System 2 modes of thought. I also study the broader sociolinguistic and cognitive dynamics of human–AI interaction, examining how language technologies shape communication, expression, and thought; this line of work includes our recent papers in Nature Human Behaviour and Trends in Cognitive Sciences on how large language models homogenize human language and reasoning.

I began my Ph.D. working with Dr. Filip Ilievski on cognitively inspired methods for reasoning in language models, which has remained a central part of my research. Under the guidance of Dr. Morteza Dehghani, I later expanded my focus to explore the interaction between linguistic behavior and emerging forms of human–AI collaboration from a sociolinguistic perspective, while also continuing my work on reasoning in LLMs and their alignment with human cognition, including how language models align with the brain systems that support human language and reasoning.

Beyond my work at USC, I have collaborated with Dr. Dan Roth at Oracle on multimodal retrieval-augmented generation (RAG) for visually rich document understanding and on agentic systems for reasoning over complex documents and heterogeneous data; with Dr. Samuel Nastase on aligning language models with brain activity; with Dr. Fred Morstatter (ISI) on factors influencing LLMs’ decision-making; with Dr. Don Tuggener and Dr. Mark Cieliebak (Zurich University of Applied Sciences) on dialogue summarization; and began my research journey as a research assistant with Dr. Behnam Bahrak, focusing on permutation tests and complex networks.

My research interests further include NLP, computational social science, knowledge graphs, and data mining, with a focus on interdisciplinary problems at the intersection of computer science, psychology, linguistics, and the social sciences.