Depression is often associated with Parkinson’s disease (PD), as is apathy. But there may be a subtle difference between the two. At the risk of oversimplifying, let’s define depression as a state of sadness and loss of interest, and apathy as an apparent lack of motivation. Put sadness and low motivation together and the result looks like someone who has stopped enjoying life. But linking the two together may be a mistake when PD is involved because what looks like a lack of motivation may be the result of motor hesitation and difficulty with set shifting (changing from one motor activity to another). I have seen this motor hesitation in my own life. I feel stuck; not because of a lack of desire but rather an inability to move. It requires a careful examination to recognize the difference.
In a previous column, I talked about scenario looping breakdowns in connection to freezing — a common PD motor symptom. Apathy with PD folks may be linked more to scenario looping breakdowns than to a mood disorder. With PD it speaks to the “unwillingness” to act. But with a breakdown in scenario looping, it may appear as the unwillingness to act when it is actually a form of freezing due to an organic neurological condition. Combine this with the “flat affect face” or facial masking that can come with PD and it can appear to the observer as apathy. A careful look may reveal that often it is not. It is a manifestation of scenario looping breakdowns.
Scenario looping is the brain’s ability to loop through scenarios, exchanging possible actions or responses, until the best course has been determined. This happens with use of language and with motor actions. In every case, the scenario has a starting point. If there is no external cue from the environment to get started, we call that spontaneous initiation; an example is engaging in speech with your partner. You wouldn’t always want to wait until your partner speaks first or provides an external cue. In a normal relationship, each person will often initiate speech spontaneously without external cueing. Patients who have damage to areas of the brain responsible for scenario looping will frequently have problems with spontaneous speech. Does this mean that they are apathetic?
Spontaneously starting a new motor sequence may be difficult for some PD patients. Another example: My partner wants me to put up a new curtain rod. This involves a series of motor tasks: getting the tools and step stool, removing the old curtain rod, and using small screws. These actions involve the use of fine motor skills which are always difficult for those with PD. The curtain rod has been leaning against the wall for a week. Is it apathy that prevents me from engaging in the task? Is it fear? It doesn’t feel that way. It feels like a physical resistance to move my body in the direction of that given sequence of motor actions. PD patients often have motor action hesitancy, and this may be misinterpreted as apathy. In a chapter of “Parkinson’s Disease: Diagnosis and Clinical Management,” Lisa M. Shulman and Mackenzie Carpenter say that great care needs to be taken when ascribing the symptom of apathy to a PD patient, and that more research is necessary.
I need to be taking that careful look, to be clear in my mind that this is motor hesitancy. Doing so will ensure that scenario looping breakdown does not become apathy in my mind, or in the minds of those who care for me. There is a risk of mentally interpreting the motor resistance as “he doesn’t care.” The distinction is very important, and I spend time in mental contemplation making the distinction clear. Muscle hesitancy and difficulty with initiating motor sequences is not apathy. Understanding the difference between apathy and scenario looping breakdown is an opportunity to reframe and enlighten. Taking the time to contemplate on the difference is time well spent.
Write a comment and tell me if you see a difference between apathy and muscle initiation in your own life. Do you have suggestions on how to use this distinction to improve your quality of life?
Note: Parkinson’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of Parkinson’s News Today or its parent company, BioNews Services, and are intended to spark discussion about issues pertaining to Parkinson’s disease.