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The cerebellum, cognition and emotions

Introduction

 If it’s true that we often think of the cerebellum as a motor component of the central nervous system, a body of research is emerging as to showcase its non-motor roles. The cerebellum has been most recently shown to be of interest in the cases of ADHD, major depressive disorder, anxiety disorders and more.

This blog will delve into the contributions of the cerebellum in these three scenarios.

ADHD

There are three diagnostic criteria for ADHD:

  • Attention deficit;
  • Impulsiveness;
  • Hyperactivity.

If some believe that ADHD is a dysfunction of the frontal-sub cortical pathway, structural and functional neuro imaging studies show changes in the prefrontal cortex, cingulum, basal ganglia, corpus callosum, and cerebral total volume. It is important to note that it is via motor development that these areas are supposed to sync and grow in use.

To add to this, there are multiple studies that have reported cerebellar changes in ADHD.

Castellanos et al. scanned adolescents diagnosed with ADHD (age 15-18) as well as healthy controls, to measure changes over a decade of brain anatomy and volume.

They found volumetric abnormalities with reduced cerebrum and cerebellum size that increased with age.

Major depressive disorder (MDD)

To be diagnosed with MDD, one needs to experience at least one depressive episode that may involve both motor and cognitive symptoms.

Cognitive symptoms consist of difficulty concentrating or indecisiveness. They have been often linked to the prefrontal cortex and limbic system in MDD.

To add to this, in addition to these brain regions, patients with MDD have also shown various abnormalities in the cerebellum.

Yucel et al. found a significantly smaller vermis, an area responsible for the regulation of emotion and cognition, in MDD patients compared to healthy controls.

When one considers that the vermis is responsible for posture and locomotion, it could be interesting to study the effects of a postural intervention on MDD.

Anxiety disorders

Anxiety disorders are associated with excessive fear and anxiety. These disorders are often accompanied by autonomic reactions, such as muscle tension and elevated heart rate.

It has been reported that impairment of the cerebellum could be linked to a few disorders where anxiety is present, such as post traumatic stress disorder (PTSD), generalized anxiety disorder (GAD), and social anxiety disorder (SAD).

Conclusion

In conclusion, if one considers the possible effect that the cerebellum can have on someone’s health, maybe we should consider the relative importance of proprioception for performance, and that, on so many levels.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4419550/

 

Balance and ADHD

What has already been reported is that balance function is worse in ADHD children than in their normal peers. The studied reviewed here (https://www.ncbi.nlm.nih.gov/pubmed/28238393) was designed to asses the effects of balance exercises on the cognitive performance of children with both ADHD and vestibular impairment.

33 children suffering from severe vestibular impairment were randomly assigned to two groups that were matched for age. Some of the children concerned performed balance, gait and eye movement exercises. The other group of children did not. It was twice a week, for 12 weeks that the chosen children performed the selected exercises.

Specific cognitive tests such as choice reaction time (CRT) and spatial working memory (SWM) were utilized to test for cognitive abilities for both groups.

As far as the CRT test goes, the children who performed the exercises performed significantly better than the children that did not.

Generally speaking, this study illustrates that vestibular rehabilitation can improve cognition.

When looking at the brain pathways involved, it can make sense to think that when the body is lacking balance, it can be harder to recruit brain areas specialized in tasks that relate to cognition. In essence, the body’s number one concern is survival. To secure body stability is primary.