Related Experiment Video
Updated: Jul 5, 2025
Assessing Changes in Synaptic Plasticity Using an Awake Closed-Head Injury Model of Mild Traumatic Brain Injury
Published on: January 20, 2023
Association of Win-Loss Record With Neuropsychiatric Symptoms and Brain Health Among Professional Fighters
Barry R Bryant1, Aaron I Esagoff1, Lisa Young1
1Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore (Bryant, Esagoff, Young, Bray, Richey, Vohra, Peters); Department of Psychiatry, University of Connecticut School of Medicine, Farmington (Kosyakova); Department of Biostatistics, University of Florida, Gainesville (Shan); Department of Neurology and Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia (Schneider); Lou Ruvo Center for Brain Health, Cleveland Clinic, Las Vegas (Bernick); Institute of Living, Hartford Hospital, Hartford, Conn. (Narapareddy).
Objective:
Repetitive head impacts in professional fighting commonly lead to head injuries. Increased exposure to repetitive head trauma, measured by the number of professional fights and years of fighting, has been associated with slower processing speed and smaller brain volumes. The impact of win-loss outcomes has been investigated in other sports, with several studies suggesting that individuals on losing teams experience more head injuries. Here, the authors hypothesized that fighters with a worse fight record would exhibit poorer brain health outcomes.
Methods:
The Professional Fighters Brain Health Study examined changes in neuropsychiatric symptoms, regional brain volume, and cognition among professional boxers and mixed martial arts fighters. These data were used to evaluate the relationship between win-loss ratios and brain health outcomes among professional fighters (N=212) by using validated neuropsychiatric symptom and cognitive measures and MRI data.
Results:
Retired fighters with a better record demonstrated more impulsiveness (B=0.21, df=48) and slower processing speed (B=-0.42, df=31). More successful fighters did not perform better than fighters with worse records on any neuropsychiatric or cognitive test. Retired fighters with better fight records had smaller brain volumes in the subcortical gray matter, anterior corpus callosum, left and right hippocampi, left and right amygdala, and left thalamus. More successful active fighters had a smaller left amygdala volume.
Conclusions:
These findings suggest that among retired fighters, a better fight record was associated with greater impulsiveness, slower processing speed, and smaller brain volume in certain regions. This study shows that even successful fighters experience adverse effects on brain health.
