Although motor deficits often accompany a mood or psychiatric disorder, most researchers have not targeted motor areas as a method to improve mental health. In a new study, researchers at Indiana University suggests that postural control problems may be a core feature of bipolar disorder, not just a random symptom.
The investigators believe attention to the postural problems can provide insights both into areas of the brain affected by the psychiatric disorder and new potential targets for treatment.
Bipolar disorder is a severe psychiatric disorder characterized by extreme, debilitating mood swings and unusual shifts in a person’s energy and ability to function.
Balance, postural control and other motor control issues are frequently experienced by people with mood and psychiatric disorders such as bipolar disorder and schizophrenia, and neurological disorders such as Huntington’s and Parkinson’s disease.
In this study, published in the journal PLoS ONE, researchers surmised that problems with postural control — maintaining balance while holding oneself upright — are a core component of bipolar disorder.
As such, the researchers believe it is possible that the motor abnormalities could appear before other symptoms, signaling an increased risk for the disorder. According, researchers wanted to know if therapies that improve motor symptoms may also help mood disorders.
“For a number of psychological disorders, many different psychiatric treatments and therapies have been tried, with marginal effects over the long term. Researchers are really starting to look at new targets,” said Amanda Bolbecker, Ph.D., lead author of the study.
“Our study suggests that brain areas traditionally believed to be responsible for motor behavior might represent therapeutic targets for bipolar disorder.”
The link between motor and mental is not as distant as some would believe. For example, try as we might, humans cannot stand perfectly still.
“Instead, we make small adjustments at our hips and ankles based on what our eyes, muscles, ligaments, tendons, and semi-circular canals tells us,” said S. Lee Hong, Ph.D., a study co-author. “The better these sensory sources are integrated, the less someone sways.”
Areas of the brain that are critical for motor control, mainly the cerebellum, basal ganglia and brain stem, also aid in mood regulation and are areas where abnormalities often are found in people with bipolar disorder.
Postural sway — a measure of the endless adjustments people make in an attempt to stand still — is considered a sensitive gauge of motor control that likely is affected by these abnormalities.
In the study, participants who had bipolar disorder displayed more postural sway, particularly when their eyes were closed, than study participants who had no psychological disorders. The troubles, which involved the study participants’ proprioception, or ability to process non-visual sensory information related to balance, were not affected by their mood or the severity of their disorder.
“It appears that people with bipolar disorder process sensory information differently and this is seen in their inability to adapt their movement patterns to different conditions, such as eyes open vs. eyes closed or feet together vs. feet apart,” said Hong, whose research focuses on how humans control motion. “The different conditions will cause people to use the information their senses provide differently, in order to allow them to maintain their balance.”
Additional research is called for as investigations involving motor control, mood and psychiatric disorders are complicated by the fact that the primary treatment for these disorders is medication, which can have severe side effects including motor control problems.
Source: Indiana University