Imagine a long plane flight.  You arrive at Heathrow and accidentally picked up several bags belonging to an elderly pensioner.  Nothing in the pensioners’ bags seem to be of use and if you wore any of the clothing contained in the bag would make other people look at you a little oddly.  This extra luggage is very similar to what psychologists call ‘comorbidities’.  Comorbidities are additional diagnosis on top of the major diagnosis you are given.  In addition to the main mental health issue that you have (e.g. OCD – obsessive compulsive disorder) other small and unwanted issues come along for the ride.  These bags are not as big as the luggage you normally travel with but the extra issues can weigh you down.

Anxiety and depression are common with OCD but a symptoms of autism spectrum disorder and attention deficit/hyperactivity disorder also can hang on as extra luggage (comorbidities).  Researcher Gideon Anholt and co-workers believe that OCD, ASD (Autism Spectrum Disorder) and ADHD (Attention Deficit Hyperactivity Disorder) can appear together because they present associated symptoms due to a common dysfunction in the brain.  Specifically in the basal ganglia. The basal ganglia is located in the middle of the brain roughly at eye level.  My interpretation of the paper is that depending on the type of dysfunction of the basal ganglia you get a mix of symptoms that are recognised as symptoms of ASD, OCD and ADHD.  The basal ganglia is not the sole brain area responsible for these symptoms but they appear frequently together as they share an underlying set of causes. For OCD in particular an inability to manage attention switching may lead to memory formation that is untrusted.  Untrusted memories are believed to be responsible for some of the OCD symptoms such as checking behaviours (e.g. door locks, oven and fridge doors).

The researchers suggest that drugs such as Ritalin could aid in OCD treatment if attention switching issues are further demonstrated to underpin some of the symptoms of OCD.


Journal article:

Anholt, G.E., Cath, D.C., Oppen, P.V., Eikelenboom, M.J., Smit, J.H., Megen, H.J., & Balkom, A.J. (2010). Autism and ADHD Symptoms in Patients with OCD: Are They Associated with Specific OC Symptom Dimensions or OC Symptom Severity? Journal of autism and developmental disorders.

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