Lee Rannals for redOrbit.com – Your Universe Online
Tel Aviv University researchers are using zoological methods to determine the difference between obsession and delusion.
Scientists recorded patients with obsessive-compulsive disorder and “schizo-OCD” as they performed tasks. Schizo-OCD is a mental disorder that combines symptoms of schizophrenia with OCD. The researchers were able to identify similarities and differences between the two disorders.
The team used zoological methods to study their patients. Scientists must study the behavior patterns of animals to make sense of their activities, simply because animals can’t talk. These same methods were used to study people with serious mental disorders, and the researchers published their findings in the journal CNS Spectrums.
“I realized my methodology for studying rat models could be directly applied to work with humans with mental disorders,” said Professor David Eilam of TAU’s Zoology Department at The George S. Wise Faculty of Life Sciences. “Behavior is the ultimate output of the nervous system, and my team and I are experts in the fine-grained analysis of behavior, be it of humans or of other animals.”
Obsessions are identified as recurring and persistent thoughts, impulses or images that are experienced as intrusive and unwanted and cause marked distress or anxiety. Compulsions are repetitive motor behaviors that occurs in response to obsessions and are performed according to strictly applied rules. Schizophrenia symptoms include delusions, hallucinations, disorganized speech, abnormal motor behavior, and diminished emotional expression.
The team recorded and compared videos of diagnosed OCD and schizo-OCD patients performing 10 different mundane tasks, like leaving home, making tea, or cleaning a table. All of the patients in the study met the criteria of the Diagnostic and Statistical Manual of Mental Disorders.
Researchers found that both OCD and schizo-OCD patients exhibited OCD-like behavior in performing the tasks, excessively repeating and adding actions. However, the schizo-OCD patients not only added some tasks, but also acted like schizophrenics. Overall, the team found that the level of obsessive-compulsive behavior in both sets of patients was the same, which suggests that both types had difficulty shifting attention from one task to another.
The schizo-OCD patients did more divergent activity over a larger area than the OCD patients, suggesting that schizo-OCD patients were continuously shifting attention.
Under one example, when an OCD patient is leaving his home, he may check the contents of his pockets repeatedly before finally taking his keys and cell phone and going to the door. Using the same scenario, a shizo-OCD patient would travel around the apartment, switching off lights in the bathroom, taking his keys, going back to the bedroom, taking his keys and phone to the door, then back into the apartment, back to the door and so on.
“While the obsessive compulsive is obsessed with one idea; the schizophrenic’s mind is drifting,” said Eilam. “We found that this is reflected in their paths of locomotion. So instead of tracking the thoughts of the patients, we can simply trace their paths of locomotion.”