Creating a foundation for connecting with and interpreting patient environments that lead to postural instability and …
Neuroplasticity refers to the brain’s ability to modify, change and adapt both structure and function throughout life and in response to experience such as postural instability. Neuroadaptation to experiences relies on the brain knowing the status of the body, both the physical as well as physiological state of the body. The brain is “fed” the status of the body via afferent sensory input from the external (exteroceptive) and internal (interoceptive) environment.
Perceiving the inner and outer body
The five external senses are comprised of the visual, auditory, olfactory, gustatory and tactile senses. Interoception is the perception of the internal state of the body and comes from several systems such as vestibular, proprioceptive, visceral, hormonal, humoral, immune, cardio-respiratory and the microbiome.
Interoceptive mechanisms ensure physiological health through the cerebral coordination of homeostatic reflexes and allostatic responses that include motivational behaviors and associated affective and emotional feelings. If afferent sensory input is inadequate or not interpreted properly by the brain, the result will be maladaptive in nature. Consequently, the physical, mental and emotional status of an individual will be compromised.
Postural instability and learning, attention and behavior issues
Sensory processing is the ability to take in, organize and integrate sensory information from our external and internal environment and respond in a meaningful and appropriate manner.
Perception, processing and integration of sensory input in the central nervous system (CNS) is the basis of all learning: academic learning, social learning, emotional learning and the development and control of motor skills. Poor processing of sensory information is associated with a variety of learning, attention and behavioral disorders as well as various psychiatric disorders.
Poor processing of sensory input, primarily visual, vestibular and proprioceptive, is the fundamental root cause associated with postural instability. A number of disorders have been associated with postural instability, including:
- Attention Deficit Hyperactivity Disorder (ADHD);
- Autism Spectrum Disorder (ASD);
- Tourette Syndrome;
- Developmental Coordination Disorder (DCD); and
- Bipolar Disorder.
Studying disorders and posture
In a very interesting study looking at bipolar disorder and postural control, the lead author, Amanda R. Bolbecker, raises the question of whether therapies that improve motor symptoms may also help mood disorders.
The study begins with the understanding that 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 is a measure of the degree of multiple adjustments people make in an attempt to stand still and is considered a sensitive gauge of motor control that likely is affected by these abnormalities.
- Lee Hong, co-author of the study, states, “We make small adjustments at our hips and ankles based on what our eyes, muscles, ligaments, tendons and semi-circular canals tells us. The better these sensory sources are integrated, the less someone sways.”
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.1 There have been many studies looking at postural control and ADHD. One study found that boys with ADHD had poorer static postural control ability and impaired function of processing visual and vestibular information compared with the normal control. Boys with ADHD-Type 1 showed particularly severe defect of static postural control and vestibular function integrating conflict information compared to normal boys. These deficits may be an important contributor to the clinical presentation of ADHD children and their cognitive deficits. Assessment and training of postural control function would be suggested during the diagnosis and treatment of ADHD children.2
Several studies highlight the fact that dyslexic children show poorer postural performances compared to non-dyslexic children, suggesting that poor postural performance observed in dyslexic children could be due to a poorer use of sensory inputs and a lack of cerebellar integration.3 One study included 50 boys with developmental dyslexia and 42 control boys. Analysis of classical parameters quantifying the center of pressure (CP) displacements along antero-posterior and lateral axes showed a significant difference between the two groups. Dyslexic children showed on average greater instability, with greater length, variability and mean power frequency of CP displacements with or without vision. These results demonstrated that postural parameters may discriminate between children with dyslexia and age-equivalent controls.4
In a study looking at postural stability and Tourette syndrome (TS), results suggested that children with TS had greater difficulty maintaining postural stability, especially when vestibular information was challenged. The results of this study provide supporting evidence for possible deficits in impaired access to vestibular information and sensorimotor integration of postural control in children with TS.5
The above disorders are just a few of many that have been associated with postural instability. As suggested in those with bipolar disorder, one must be mindful of brain circuits and functional connectivity associated with these disorders and how they overlap with postural control. The brain relies on proper afferent sensory input from the body in order to “feed” the CNS with the necessary input for proper function.
Creating a strong foundation with custom orthotics
Proprioceptive input from the feet and ankles trigger balance and gait movements which will affect vestibular and proprioceptive input to the CNS. Studies using orthotics and their effects on postural control have led to several theories about how they achieve improvements in balance.
The proposed balance-improving mechanisms include:
- Improved joint alignment of the rear foot/ankle complex;
- Reduced strain on the ligaments and tendons around the ankle;
- Shifting of ground reaction forces (CoP) to a more optimal position; and
- Enhanced sensory feedback from the plantar surface of the foot.6
By changing joint position and reducing strain on ligaments, custom orthotics that support all three arches of the foot are able to improve joint proprioception and affect overall posture and postural stability. This subsequently “feeds” the brain necessary sensory information needed for optimal learning, attention and behavior.
MONIKA A. BUERGER, BA, DC, a 1991 graduate of Life Chiropractic College West, is the owner of Eagle Canyon Wellness & Sensory Development Center in Ammon, Idaho. She is a teacher, international lecturer, author and the founder of Intersect4Life Educational Seminars and developing MINDS certification program in childhood and adolescent neurodevelopment. For additional information, visit intersect4life.com and devmindsu.com.