New research suggests origin of hallucinations, delusions experienced by people with schizophrenia

December 15, 2021

Though persistent hallucinations and delusions are defining characteristics of schizophrenia and schizoaffective disorders, their origins are unknown. But something as simple as a bunch of moving dots might suggest how it is possible to see and hear things that are not there.

Imagine looking at a black screen with moving white dots on it. At first, many dots move to the right. Then, after a short amount of time, they switch to moving straight down. Portrait of ASU Assistant Professor of psychology Gi-Yeul Bae. Gi-Yeul Bae, assistant professor of psychology at ASU. Download Full Image

“This task is simple, but not easy,” said Gi-Yeul Bae, assistant professor of psychology at Arizona State University. “Because not all the dots are moving toward the same direction, you need to keep paying attention and detect when the motion changes direction.”

Bae and collaborators recently published a study in JAMA Psychiatry using this task. The study shows that people diagnosed with schizophrenia or schizoaffective disorder had difficulties detecting motion changes that were easily reported by healthy control participants. This work suggests that hallucinations and delusions could result from the brain failing to update what is perceived based on new information, like a change in motion direction. 

“People with schizophrenia and schizoaffective disorder show different types of symptoms, including hallucinations and delusions, which are at a very basic level unusual perceptual phenomena,” Bae said. “This study tested the idea that hallucinations and delusions might happen because people fail to update perceptual information.”

The research team also measured the severity of psychotic symptoms experienced by the participants diagnosed with schizophrenia or schizoaffective disorder. Symptom severity was positively correlated with how frequently participants with schizophrenia or schizoaffective disorder did not report motion changes. 

“The proportion of times a participant with schizophrenia or schizoaffective disorder reported the initial motion direction, and not the change in motion, was significantly correlated with how severe their symptoms were,” Bae said.

The research team replicated the experiment with participants recruited from Baltimore and New Haven, Connecticut. The findings were the same in both experiments: People with schizophrenia or schizoaffective disorder were less likely to report changes in dot motion, unlike the healthy control participants.

“The replication of these findings provides strong evidence that sensory hallucinations and delusions might be rooted in a failure of updating perceptual evidence,” Bae said.

This study was a collaboration between the ASU Department of Psychology; University of Maryland School of Medicine; University of Chicago, Illinois; Yale University; and the University of California, Davis.

Science writer, Psychology Department


New ASU course focuses on dismantling racism, reshaping the humanities

December 15, 2021

The summer of 2020 gave way to the largest protests for racial justice and civil rights in the U.S. during the 21st century. Realizing the need to stand in solidarity with human-rights protesters who took to the streets and the desire to implement effective and meaningful change to actively fight against racism, the School of Historical, Philosophical and Religious Studies at Arizona State University created the Anti-Racism Committee.

Part of the mission of the committee is to “make lasting reforms in our primary area of expertise as educators and teachers by critically rethinking pedagogical approaches, course curriculums and student events to center Black and brown voices and experiences.”  ASU building with a sunset in the background. Download Full Image

In line with the mission, and to help students and the broader community understand the ongoing realities of systemic racial violence and oppression, new courses within the school were developed and continue to be developed. 

One such course launched for the first time in fall 2021, titled “From Racism to Justice: Reshaping the Humanities in the 21st Century.” The iCourse emerged from the work of Associate Professor of history Julian Lim, Lecturer of philosophy Michelle Saint and Assistant Professor of religious studies Shamara Alhassan, who taught the course.

The course is the first in the school to be listed across the three disciplines that focuses on racism within the humanities.

“The purpose of this introductory course is to train a new generation of scholars to use critical humanistic inquiry to dismantle racist epistemology and, to this end, provide a basic understanding of the way race, racism and white supremacy function across our disciplines, and ultimately help us reshape the humanities to center justice, equity and reparations,” Alhassan said. 

The students who took the course were drawn to it in different ways. Rhianna Cheetham is earning a bachelor’s degree in social work and initially chose the course to fulfill a cultural diversity credit.

“I expected this course to touch on how racism is occurring, what caused it and what is working in those aspects of improvement,” Cheetham said. “This class was about these things, but also so much more than that. This class focused on the responsibility that we have, as students, teachers and community contributors, to have epistemic reparations and not only recognize injustice, but do something about it.”

Farhat Ali, a double major in political science and women and gender studies, took the course because she had taken a previous class with Alhassan and enjoyed her teaching style.

“This course was everything I expected it to be,” Ali said. “It tied in history, contemporary issues surrounding race and racism, feminism and gender, intersectional identities and even music in order to create a framework for understanding how we move towards liberation.”

Engineering undergraduate JJ Sales was intrigued by the title of the course and decided to enroll. 

“I wanted to be involved in talking and especially learning more about racism besides reposting and retweeting posts on what we hear in the news and or facts about racism like how America was built by racism,” Sales said. 

The class used Yellowdig as the main platform for communication, which students said contributed to “deeper conversations” and allowed room for “extensive conversation.”

“(Alhassan) has such a fresh and unique take on how she teaches, and I love that she brings in so many different elements and forms of inclusive education to support all kinds of learners,” Ali said. “She is also incredibly open to conversations and feedback, and I love that she’s always readily available to support her students.”

Along with the discussions and readings about the broader issue of racism, students learned about current issues at Arizona State University and allowed them to develop ways to actively combat them.

“The final assignment for the course provides students the opportunity to create epistemic reparation action plans for SHPRSSchool of Historical, Philosophical and Religious Studies and ASU,” Alhassan said. “These plans encourage students to apply what they have learned about racism in the humanities to implement practical, sustainable and accountable solutions for addressing these issues in SHPRS and ASU.”

The plans developed by the students will be used to support the work of the Anti-Racism Committee and the work within the school to address the issue of structural racism. 

“I'm just grateful that this class exists, and I just hope that in the future that most if not all colleges and schools across America have this kind of class,” Sales said.

Rachel Bunning

Communications program coordinator, School of Historical, Philosophical and Religious Studies