Lei Fan

I am a Postdoctoral Researcher at the Department of Clinical Neuroscience, Karolinska Institutet, working with Professor Mats J. Olsson. I obtained my PhD from Vrije Universiteit Amsterdam. Before joining Karolinska Institutet, I was a postdoctoral researcher at the Centre for the Experimental-Philosophical Study of Discrimination (CEPDISC), Aarhus University, and a visiting researcher at the University of Oslo.

My research adopts an evolutionary and socio-functional perspective to understand how humans navigate survival and social challenges through emotion. I am particularly interested in disgust as a regulatory system linking biological defense with social behavior, from pathogen avoidance to interpersonal rejection and social exclusion.

My work examines how these emotional and behavioral processes are shaped by social relationships, physiological conditions, ecological constraints, and cultural contexts. Integrating experimental, cross-cultural, and individual-differences approaches, I seek to understand how emotions regulate interactions between individuals and their biological and social environments.

Pathogen Disgust and the Social Allocation of Infection Risk

I investigate how people manage and allocate pathogen-related risks across social relationships, including whose infection risks they tolerate, whom they avoid, and when they disclose or conceal illness.

Conditional Immune Tuning

I examine how behavioral and physiological immune processes interact through complementary, compensatory, or decoupled responses. My temporal threat–capacity framework considers how these dynamics vary with pathogen threat, physiological resistance capacity, and timescale across biological and ecological contexts.

Moral Emotions, Cross-Cultural Recognition, and Discrimination

I investigate how anger and disgust regulate different forms of social confrontation, punishment, distancing, and exclusion. My current work examines cross-cultural emotion expression and recognition, particularly how mismatches between emotional expression and perception across group boundaries may contribute to discrimination.

Hierarchy and Social Representation

An emerging line of my research explores how people mentally represent social class, leadership, and social hierarchy, and how ecological conditions and resource constraints shape expectations about social structure.

My teaching experience includes undergraduate and graduate-level courses in social psychology at Aarhus University and the University of Oslo. My teaching focuses on social inequality, intergroup relations, and the evolutionary and psychological foundations of human social behavior.