Sometimes we miss the obvious. Sometimes scientific connections stare us in the face, and we don’t see them, and therefore they are left unexplored. Mercede Erfanian, a prominent misophonia researcher at the University College of London, recently directed my attention to the importance of the relationship between misokinesia, misophonia, and new findings regarding the involvement of movement in misophonia (Kumar et al., 2021). Author Mercede Erfanian and I share similar thoughts.
Misokinesia or hatred of movement, was first proposed by Schröder and his colleagues (Schröder et al., 2013). It is best defined as a high magnitude of sympathetic nervous system response with emotional and cognitive consequences. Responsivity results from an intolerance to certain visual stimuli and/or movements. Misokinesia often occurs with misophonia, a common prevalent neurophysiological disorder, best described as decreased tolerance to specific auditory triggers with certain psychoacoustic features such as repetitiveness (Swedo et al., 2021; Brout et al., 2018).
Studies indicate that the misokinesia triggers are predominantly attributed to misophonia triggers such as orofacial behaviors. However, movement-related stimuli such as feet jiggling and finger tapping (Rouw & Erfanian, 2017) do not necessarily have corresponding auditory features. Notably, however, many misophonia sufferers describe being able to hear sounds that go along with those movements. Therefore, the relationship between misokinesia and misophonia remains difficult to parse out.
Both misokinesia and misophonia share symptomatology such as sympathetic nervous system arousal with corresponding feelings ranging from irritation to anger and including a sense of being overwhelmed by outside stimuli. Similarly, with both conditions, the sufferer often experiences anxiety related to the presence of a trigger and the urge to flee from it. (Schröder et al., 2013; Rouw & Erfanian, 2017).
The recent brain-imaging study by Kumar and colleagues (Kumar et al., 2021) may provide insight into the neural basis of misokinesia, although the study was aimed at investigating misophonia. In this study, researchers found that the brains of misophonia sufferers were wired differently and consequently function differently.
Of particular interest is the premotor cortex of misophonic brains. This brain region is within the frontal lobe of the brain just anterior to the primary motor cortex. The study demonstrated that the primary motor cortex was hyper-connected to the auditory and the visual cortices, leading to hyper-communication between them relative to non-misophonia sufferers.
This means that when sufferers are exposed to misophonia auditory or auditory and visual triggers such as chewing, the premotor cortex also activates. This is the part of the brain that is responsible specifically for the orofacial movement of the mouth and nose, and this phenomenon does not occur in the brains of non-misophonic people.
Moreover, the premotor cortex is the biggest hub of mirror neurons (with the highest density) (Kilner & Lemon, 2013). Mirror neurons are motor neurons that fire both when we act and when we observe action performed by another. Hence, these neurons allow us to mirror the behavior of the others and function as though the observer was performing the action.
The automatic, perhaps unwanted activation of mirror neurons in the premotor cortex may result in negative experiences following the triggers. In other words, seeing auditory and visual triggers potentially causes the overactivation of mirror neurons and brings about unpleasant emotional and physiological symptoms.
Mercede Erfanian, one of the paper’s authors, stated that this work supports a neurological basis for these related disorders and may help explain why some people with misophonia say that they are compelled to mimic the sounds/movement as a coping strategy, a term coined by Kumar as “hyper-mirroring.”
The activation of the primary motor cortex in response both to auditory and visual triggers gives new meaning to both misophonia and misokinesia, as well as their relationship. These findings demonstrate the need for further research in this area, particularly that which will translate to treatment.
References
Brout, J.J.; Edelstein, M.; Erfanian, M.; Mannino, M.; Miller, L.J.; Rouw, R.; Kumar, S.; Rosenthal, M.Z. Investigating Misophonia: A Review of the Empirical Literature, Clinical Implications, and a Research Agenda. Front. Neurosci. 2018, 12, 36
Kumar, S., Dheerendra, P., Erfanian, M., Benzaquén, E., Sedley, W., Gander, P. E., Lad, M., Bamiou, D. E., & Griffiths, T. D. (2021). The Motor Basis for Misophonia. The Journal of neuroscience : the official journal of the Society for Neuroscience, 41(26), 5762–5770. https://doi.org/10.1523/JNEUROSCI.0261-21.2021
Rouw, R., and Erfanian, M. (2017). A large-scale study of misophonia. J. Clin. Psychol. doi: 10.1002/jclp.22500.
