Can a Simple Memory Task Help Diagnose Obsessive-Compulsive Disorder?

What you need to know

• People with obsessive-compulsive disorder (OCD) performed worse than healthy individuals on a memory task called delayed non-matching to sample (DNMS).
• The DNMS task may activate a specific brain region (the lateral orbitofrontal cortex) that is thought to be involved in OCD.
• This simple memory test could potentially be used to help diagnose OCD or monitor treatment effectiveness.

A New Tool for Diagnosing OCD

Obsessive-compulsive disorder (OCD) is a mental health condition that affects 2-3% of people worldwide. It causes intrusive, unwanted thoughts (obsessions) and repetitive behaviors or mental acts (compulsions) that a person feels driven to perform. While we have effective treatments for OCD, including medications and therapy, diagnosing the condition can sometimes be challenging.

Now, a new study suggests that a simple memory task could help identify people with OCD. Researchers found that individuals with OCD performed worse on a specific type of memory test compared to people without the disorder. This finding could potentially lead to a new tool for diagnosing OCD or tracking how well treatments are working.

Testing Memory in OCD

The study, published in the journal Translational Psychiatry, involved 20 people diagnosed with OCD and 20 healthy individuals without the disorder. All participants completed two different memory tasks on a computer:

1. Delayed non-matching to sample (DNMS): Participants were shown an abstract pattern and then, after a short delay, had to choose between two patterns, selecting the one that was different from the original.

2. Delayed matching to sample (DMS): This was similar, but participants had to choose the pattern that matched the original.

The key difference is that the DNMS task requires inhibiting the natural tendency to choose the familiar pattern, instead selecting the novel one. This type of inhibition is thought to involve a brain region called the lateral orbitofrontal cortex, which has been implicated in OCD in previous research.

Key Findings

The study revealed several important results:

1. People with OCD performed worse than healthy participants on both memory tasks, making more mistakes and taking longer to respond.

2. The difference in performance was more pronounced for the DNMS task compared to the DMS task.

3. Among people with OCD, those with more severe symptoms (as measured by a standard OCD rating scale) tended to perform worse on the DNMS task.

These findings suggest that the DNMS task may be particularly sensitive to the cognitive difficulties experienced by people with OCD.

Why This Matters

Dr. Redwan Maatoug, the study’s lead author, explains the significance: “Our results indicate that people with OCD have particular difficulty with tasks that require inhibiting a natural response. This aligns with what we know about OCD – that individuals often struggle to inhibit unwanted thoughts or behaviors.”

The study’s findings are important for several reasons:

1. Potential diagnostic tool: The DNMS task could potentially be used as a simple, objective test to help diagnose OCD or differentiate it from other conditions.

2. Treatment monitoring: Performance on the DNMS task might be a way to track how well OCD treatments are working, complementing subjective symptom reports.

3. Understanding OCD biology: The results provide further evidence for the involvement of the lateral orbitofrontal cortex in OCD, helping researchers better understand the disorder’s underlying biology.

4. New treatment targets: By identifying specific cognitive processes affected in OCD, this research could lead to new treatment approaches targeting these difficulties.

Limitations and Future Directions

It’s important to note that this was a relatively small study, and the findings need to be replicated in larger groups of people. Additionally, most of the OCD participants were taking medications, which could have affected their performance on the memory tasks.

Future research could explore:

• Whether DNMS task performance can distinguish OCD from other mental health conditions
• How DNMS performance changes with successful OCD treatment
• Whether training to improve DNMS task performance could help reduce OCD symptoms

Conclusions

• A simple memory task (DNMS) reveals differences in cognitive performance between people with OCD and those without the disorder.
• This task may be particularly sensitive to the brain processes involved in OCD.
• While more research is needed, the DNMS task could potentially become a useful tool for diagnosing OCD and monitoring treatment progress.

This study highlights how seemingly simple cognitive tasks can provide valuable insights into complex mental health conditions like OCD. As our understanding of the disorder’s underlying biology improves, we move closer to developing more targeted and effective treatments.