Exploring How Psychosis Affects Cognition

Rather, as studies by Barch’s group and others reveal, people with schizophrenia have challenges with the subsequent stages of motivational behavior—anticipating future rewards, making plans to get those rewards, and exerting effort to execute the plans.

Barch cited a 2019 study that found that people with schizophrenia reported far less anticipatory pleasure than people without the disorder prior to conducting a computer task with the chance of monetary awards. However, upon winning they were just as happy as the control. Yet, when repeating the task after winning, their anticipation levels remained low. “So, they are either not remembering how they just felt in the moment, or they don’t have the ability to represent their feelings in advance,” she said.

In another study, Barch and colleagues found that when offered multiple tasks of varying difficulties, people with schizophrenia showed less desire to pick ones requiring more effort, regardless of payout. She noted that even people with major depression were willing to put in more effort once rewards were high enough.

Barch acknowledged that specialized laboratory assessments do not reflect what people are doing in their daily lives, but real-time smartphone surveys she has conducted with study participants have supported the laboratory results. “We found that individual willingness to exert effort correlates with how well these people perform in their daily goal-oriented activities and how their clinicians rate their overall motivation.”

Looking ahead, Barch hopes that mobile technology can be used to help individuals overcome their motivation challenge, whatever areas (anticipating, planning, and/or exertion) are affected. “At the end of the day, these people are enjoying positive activities when they happen, and we need to find ways to enable more of these experiences to happen.”

On the other side of the coin are the experiences most people with schizophrenia want to avoid—namely the hallucinations, delusions, and confusion that comprise psychosis. But while this term carries strong negative connotations, it is not uncommon for people across all walks of life to have psychosis-like experiences (PLEs), said Nicole Karcher, Ph.D., during her talk at the BBRF conference.

Karcher, a mentee of Barch and assistant professor of psychiatry at Washington University, was the recipient of BBRF’s 2024 Maltz Prize for Innovative and Promising Schizophrenia Research. (The Maltz Prize recipient is selected by the Lieber Prize winner.)

Maybe it’s a long-held superstition, a bout of suspicious thinking, or an odd perceptual disturbance—“Did someone just call my name?”—but PLEs by themselves can be innocuous, Karcher said.

She noted that recent data from the nationwide Adolescent Brain and Cognitive Development (ABCD) study found that about 60% of youth already reported having at least one PLE by age 11. And though the occurrence of a PLE is a risk factor for future schizophrenia, just a small subset of these youth will go on to develop the disorder. What Karcher has been examining is how to identify which youth are at-risk of future psychosis.

In her research, Karcher has found that youth who have frequent PLEs and find them distressing are at greater risk of developing psychosis. Further, some of the strongest risk factors for developing persistent PLEs were environmental adversities like bullying. On the positive side, a study she conducted in 2022 found that providing social support to children in marginalized communities reduced the connection between experiencing discrimination and having distressing PLEs.

Identifying ways to reduce the frequency of distressing PLEs is important even for those individuals who don’t transition into psychosis, Karcher said. Additional research her team has done has found that distressing PLEs adversely affect cognitive domains like processing speed, and that within two years of manifesting PLEs can bring about noticeable changes in thinking and memory. Functional imaging studies have even shown that the brain activity of people experiencing repeated, distressing PLEs resembles those of individuals with Alzheimer’s.

Other researchers recognized at this year’s BBRF event were: