By Todd Taylor
A small initial study by University of Florida researchers found evidence of alterations in one of the earliest stages of visual processing, known as initial perception, in people with obsessive-compulsive disorder.
The study included 26 participants with OCD who underwent an electroencephalography, or EEG, recording while completing tasks, such as pushing a button every time a letter of the alphabet appeared in between several surrounding letters. The participants were compared to a control group of 35 healthy age-matched participants.
“While other studies have looked at objects that might trigger OCD symptoms, our study employed emotionally-neutral objects, such as letters of the alphabet, that should not trigger OCD symptoms,” said Elizabeth Chapman, a graduate student in the UF Department of Neuroscience.
“Our study shows that this difference in early visual processing is not reliant upon cues related to OCD, meaning there may be something fundamentally different about how the brains of people with OCD process visual information of any kind that may contribute to or manifest in certain symptoms of the disorder,” added Carol Mathews, M.D., chair of the UF Department of Psychiatry and director of UF’s Center for OCD, Anxiety and Related Disorders.
The study, co-led by Chapman and Mathews, was recently published in the journal Clinical Neurophysiology.
Further research is needed to replicate the data in an additional group with OCD using different tasks and to determine whether other parts of the visual processing stream are altered in response to neutral objects, the researchers said. They will also try to determine whether altered visual processing is associated with the sensory hypervigilance seen in people with OCD.