How the Brain Anticipates Positive Experiences May Contribute to Resilience After Trauma, Study of World Trade Center Responders Finds
New research shows how ‘reward processing’ varies among 9/11 responders, pointing to potential new targets for PTSD treatment
How the brain responds to anticipated rewards may play an important role in psychological resilience after traumatic experiences, according to a new study of 9/11 World Trade Center responders. The findings, published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging [https://doi.org/10.1016/j.bpsc.2026.07.003], suggest that the brain’s ability to detect and respond to positive information may help buffer the effects of trauma exposure and point to potential new targets for treating posttraumatic stress disorder (PTSD).
Thousands of workers involved in rescue, recovery, and cleanup efforts after the September 11, 2001, attacks experienced unprecedented trauma. Yet many of these individuals demonstrated remarkable psychological resilience despite their exposure to traumatic events.
Reward processing is the brain's system for recognizing positive experiences, motivating behavior, and helping us learn from outcomes that benefit us. These experiences can be either anticipated – such as a reminder of an upcoming positive outcome – or directly experienced. Psychological factors that rely on intact reward processing and anticipation, including the capacity for positive emotions, optimism, and hope, have long been associated with greater resilience to stress. However, the brain mechanisms underlying this relationship have rarely been studied.
“Little is known about brain function during reward anticipation in resilient individuals,” said lead investigator Adriana Feder, MD, Professor of Psychiatry at the Icahn School of Medicine at Mount Sinai. “This study is unique in its focus on the function of reward circuitry in highly resilient individuals, compared with those with chronic PTSD and lower WTC-exposed controls. All participants were involved in rescue and recovery work following the 9/11 attacks on the WTC, but the severity of exposure varied.”
In the new study, researchers examined brain activity approximately two decades after 9/11, among rescue and recovery workers from the WTC Health Program General Responder Cohort. Participants included individuals with and without chronic WTC-related PTSD, as well as responders with varying levels of exposure to potentially traumatic elements of the 9/11 attacks and their aftermath. Researchers used functional magnetic resonance imaging (fMRI) to measure and map brain activity while participants completed a reward-based task with each trial including a reminder of whether their performance on the upcoming trial could result in winning or losing money.
“We wanted to understand why some World Trade Center responders developed chronic posttraumatic stress disorder, while others maintained good psychological health despite experiencing similar extreme stressors during recovery efforts,” said co-lead investigator Robert H. Pietrzak, PhD, MPH, Professor of Psychiatry at Yale School of Medicine. “Most people recognize PTSD symptoms such as flashbacks, intrusive memories, and hypervigilance. However, PTSD can also diminish a person’s capacity to experience positive emotions, including happiness, enjoyment, and love.”
Differences in brain reward processing
Researchers divided participants into three groups:
- Responders with chronic WTC-related PTSD
- Psychologically healthy trauma-exposed controls, including:
- A. Highly resilient responders: Individuals with substantial exposure to potentially traumatic elements of the 9/11 WTC attacks, such as finding human remains or being caught in the dust clou
- B. Lower WTC-exposed responders: Individuals who had a lower level of exposure to potentially traumatic elements during their WTC recovery work
- A. Highly resilient responders: Individuals with substantial exposure to potentially traumatic elements of the 9/11 WTC attacks, such as finding human remains or being caught in the dust clou
The highly resilient group showed the strongest increase in activity in brain regions involved in processing rewards. This included the nucleus accumbens, which is involved in detecting rewards, and the ventromedial prefrontal cortex, which helps the brain evaluate and weigh rewards.
The increase in activation in these regions was significantly greater in the highly resilient group than in both the chronic PTSD group and the lower WTC-exposed group.
“Notably, when we surveyed participants about reward-related resilience factors like positive emotionality and hedonic experience, their responses only distinguished between responders who had PTSD, and those who did not,” said Saren Seeley, PhD, who conducted the neuroimaging analyses as a postdoctoral fellow working with Drs. Feder, Pietrzak, and Mercedes Perez-Rodriguez, MD, PhD, Associate Professor of Psychiatry at the Icahn School of Medicine. “This highlights that the brain imaging data captured something distinct from self-report.”
“One intriguing hypothesis that warrants future investigation is whether this protective neural capacity may be a modifiable therapeutic target, i.e., whether we can ‘train the brain’ to better anticipate positive outcomes to prevent or treat PTSD,” said Dr. Perez-Rodriguez, co-lead investigator of the study.
About the Mount Sinai Health System
Mount Sinai Health System is one of the nation’s leading integrated academic health systems and one of the largest in the New York metropolitan area. Its comprehensive system includes seven hospitals, more than 400 outpatient practices, over 600 research and clinical laboratories, the Icahn School of Medicine at Mount Sinai, the Graduate School of Biomedical Sciences, and the Mount Sinai Phillips School of Nursing. Together, the Health System comprises approximately 48,000 employees, more than 9,000 physicians, and 8,600 nurses.
As a leading learning health system, Mount Sinai combines clinical expertise with scientific discovery to improve patient care while training the next generation of health care and biomedical leaders. The Health System provides care across every stage of life, from prenatal care through geriatrics, while advancing personalized medicine through artificial intelligence, data science, and biomedical research.
Mount Sinai is consistently recognized among the nation’s leading academic health systems for patient care, research, and education. The Mount Sinai Hospital is ranked No. 1 in New York by Newsweek and No. 5 on the magazine’s World’s Best Hospitals list. The Icahn School of Medicine at Mount Sinai ranks No. 11 among U.S. medical schools and No. 1 among freestanding medical schools for National Institutes of Health funding, reflecting the strength of its scientific enterprise and leadership in biomedical research.