In the largest known brain imaging study, scientists from Costa Mesa, Calif.-based Amen Clinics, Google, John’s Hopkins University, the University of California, San Francisco, and UCLA  evaluated 62,454 brain single photon emission computed tomography (SPECT) scans of more than 30,000 individuals from 9 months to 105 years of age, to investigate factors that accelerate brain aging. SPECT tomography evaluates regional cerebral blood flow in the brain that is reduced in various disorders.

For the study, the researchers used brain SPECT imaging to determine aging trajectories in the brain and which common brain disorders predict abnormally accelerated aging. They examined these functional neuroimaging scans from a large multi-site psychiatric clinic for patients who had many different psychiatric disorders, including bipolar disorder, schizophrenia, attention deficit hyperactivity disorder (ADHD), and substance abuse. In total, the researchers studied 128 brain regions to predict the chronological age of the patient. Older age predicted from the scan compared to the actual chronological age was interpreted as accelerated aging.


According to the researchers, the study’s results revealed that a number of brain disorders and behaviors predicted accelerated aging, especially schizophrenia, which showed an average of 4 years of premature aging. Among other findings, the results showed that cannabis abuse caused 2.8 years of accelerated aging in study participants, while alcohol abuse only accelerated brain aging by 6 months. Finally, the results of the study revealed bipolar disorder accelerated aging by 1.6 years, while ADHD sped up the aging process of the brains of participants in the study by 1.4 years.

“Based on one of the largest brain imaging studies ever done, we can now track common disorders and behaviors that prematurely age the brain. Better treatment of these disorders can slow or even halt the process of brain aging,” says the study’s lead author, psychiatrist Daniel G. Amen, MD, founder of Amen Clinics, who discusses the study results in a related video.

“This is one of the first population-based imaging studies, and these large studies are essential to answer how to maintain brain structure and function during aging,” adds George Perry, PhD, chief scientist of the Brain Health Consortium from the University of Texas at San Antonio. “The effect of modifiable and non-modifiable factors of brain aging will further guide advice to maintain cognitive function.”