Ullrich is a cognitive psychologist doing research on human memory and misinformation processing. Most of his recent work has looked at why people continue to believe in information that has been clearly retracted or invalidated.
Ullrich receives funding from the Australian Research Council.
Fellow of the Psychonomic Society; UWA Young Investigator Award 2011; ARC Postdoctoral Fellow 2011-2015; UWA Vice-Chancellor's Mid-Career Research Award 2014; ARC Future Fellow 2020-2024