The Cerebellum in a Technology-Driven World

Introduction

The role of evolution and the process of adapting to the ever-changing or enhancing nature of the environment can have long-lasting effects on the behaviours and structures of human anatomical structures. There have been a few examples of how certain body parts or structures have been termed as ‘useless’ over the course of a few million years. It has been studied that there are some body parts which have no use in today’s day and age, however, were once very necessary for the functioning of our ancestors. The appendix, for example, had associations with the digestion of plants rich in cellulose, however, no real or definite function has been found to date. Another such example is the tailbone, these were known to help with mobility and balance, but through evolution, the tail shrank as human posture and way of walking (upright) emerged. Provided above are great examples of how the change in environment can elicit changes in the anatomy of a human for better adaptation. Similarly, this paper will explore the chance of the brain structure, cerebellum, becoming non-adaptive as we strive for a more technology-driven environment.

Cerebellum

The cerebellum is a Latin word, which means ‘little brain’. It is also called the ‘Rodney Dangerfield of the brain’ coined by Jeremy Schmahmann because the structure doesn’t seem to get the amount of importance it may deserve. (Hollomon, 2019). It is a hindbrain structure which is associated with motor movement, coordination, and balance. Although it occupies a very small area of the brain (approx. 10%), it consists of many neurons, which make up the nervous system. It is located at the back of the brain, behind the brainstem, below the temporal and occipital lobes. Just like the brain, the cerebellum is also divided into two hemispheres. In terms of age, the cerebellum is a rather older part of the brain, developed quite early compared to the other parts of the brain. (Guy-Evans, 2021).

The cerebellum’s main role is unconscious motor regulation. Associated functions of the cerebellum are as follows: coordination of voluntary movement (conscious), balance, posture, motor learning, sequence learning, reflex memory, mental function and in some 3 areas of emotional processing. According to the categorisation of functions of the cerebellum, it can be divided into three areas: Spinocerebellum (regulation of body movements); Vestibulocerebellum (balance and eye flexes); Cerebrocerebellum (the largest area responsible for planning movements and motor learning, controls muscle activation and eye movements). (Guy-Evans, 2021).

Life without Cerebellum: Cerebellar Agenesis

Although the cerebellum is known to have control over so many neurons needed in the functioning of the nervous system, it is possible and has been proven that humans can live without it. The phenomenon or condition in which the cerebellum never develops from birth is called ‘cerebellar agenesis’. These individuals don’t have a cerebellum, in place of that, there is just an empty space.

Individuals with cerebellar agenesis tend to show characteristics of clumsiness, show difficulties with walking, fine motor skills (writing, typing, opening doors etc), and issues with speech. They also exhibit shallow emotional, social and intellectual abilities. Hence, they may be seen to have difficulty in developing deep, complex and meaningful relationships with their spouses, friends or family. (Hollomon, 2019). Although all these symptoms and limitations are identified, it has also been found that individuals who were born with cerebellar agenesis seem to fair well when it comes to living and functioning without the cerebellum than individuals who may have damaged or lost their cerebellum sometime throughout their later life. This discrepancy could be explained through the concept that the brain is always adapting and rewiring and can be shaped to cater to the ever-changing environmental needs. It can be explained with the support of the concept that other brain areas or structures adapt and compensate for the absence of the cerebellum (in the case of cerebellar agenesis). In other words, the role of the cerebellum is transferred to other parts of the brain, so the individual can still continue to live normally. (Hollomon, 2019). However, if you were to just wake up without a cerebellum tomorrow, the same transference of role to other parts of the brain wouldn’t happen, this is because your brain isn’t or wouldn’t have developed in such a way to take over the extra roles and responsibilities which are lacking due to the absence of the cerebellum.

Cerebellar Agenesis: Research

Johnathan Keleher was born without a cerebellum, during early childhood, he was seen to miss the majority of the developmental milestones (sitting, walking and talking) that every child usually goes through. At the age of 5, a brain scan revealed the absence of the cerebellum. To date, although he does have a few symptoms which make him distinct from normal functioning, his brain has adapted to the lack of such a prominent brain structure. Although he has issues with his fine motor skills, speech, and reaction times, he has learnt to deal with these challenges. (Hollomon, 2019). Similarly, another study revealed that an individual, H.C. despite having no cerebellum had a manual labour job, and “his working life was not curtailed by his cerebellar agenesis.” (Boyd, 2010). This provided evidence for the fact that maybe the concept of ‘brain plasticity’ and the compensation done by other brain areas for the lack of the cerebellum is what occurs in individuals with cerebellar agenesis, their brain develops in a different way than normal individuals to aid with the lack of cerebellum. It also in turn gives rise to the consensus that individuals do have the possibility of living independently and maintaining jobs (mainly dependent on motor skills) without a cerebellum. (Boyd, 2010). Arrigoni et al., (2015) found that the cerebral cortex may be involved in compensating for some functions that otherwise the cerebellum is in charge of. It was also evident that, with time, the individual with cerebellar agenesis tended to learn the motor skills, once again providing evidence that the plasticity nature of the brain is what helps with the compensation of the absence of the cerebellum. (Arrigoni et al., 2015). Brain plasticity was seen in another case by Velioglu et al., (1998). Issues such as ataxia of limbs, gait and stance, and cerebellar oculomotor signs were seen to gradually improve as the individual’s brain developed. According to Dow and Moruzzi (1958) and Sener and Jinkins (1993), the acknowledgement or recognition of the absence of the cerebellum gives rise to the plasticity of the remaining brain structures, which aids in compensation of the lack of the cerebellum. (Velioglu et al., 1998).

Role of Cerebellum in a Technology-Driven World

Every day, the world is witnessing technological advancements, in terms of turning everything digital. Slowly, we are trying to mimic our once-human functions into digital functions. Examples such once we used to write, now we type, we used to walk as means of transport, and now we have various artificial means of transportation. Technological advancements have made, humans daily functioning a lot easier.

Robotic technology has given rise to the recognition that humans don’t need to put in much effort anymore. We have become so lazy and reliant on technology that it may have started to affect our anatomical structures. This can be supported by the concept of ‘atrophy’, the partial or complete wasting away of a part of the body. So, as our world or environment continues to advance towards technology and the use of robots to fulfil every human need or job increases, the use of our neck, hands, arms, muscles, and in turn any motor movement for that matter diminishes. Hence if motor movement is diminished, then the usage and size of our cerebellum would slowly shrink as well, as the main role of the cerebellum is motor movement, balance, posture etc. As it is, there have been cases of individuals being born without a cerebellum, and are managing to function and live a normal life. This could imply that slowly and gradually, the brain would develop in such a way that it would compensate the major necessary functions of the cerebellum (which we require in the current environment) to other parts of the brain and eventually eradicate the need for a cerebellum altogether.

On the other hand, if the need for movement is eradicated in the daily functioning of a human, then the concept of atrophy would begin in terms of the structure of the cerebellum. Hence, eventually, as the environment changes and becomes more technologically dependent, the structure of the cerebellum may become non-adaptive.

References

Arrigoni, F., Romaniello, R., Nordio, A., Gagliardi, C., & Borgatti, R. (2015). Learning to live without the cerebellum. NeuroReport, 26(14), 809-813. https://10.1097/WNR.0000000000000428

Boyd, C. A. R. (2010). Cerebellar agenesis revisited. Brain, 941-944. https://doi.org/10.1093/brain/awp265 Cerebellum: What it is, function & anatomy. (n.d.). Cleveland Clinic. https://my.clevelandclinic.org/health/body/23418- cerebellum#:~:text=Your%20cerebellum%20is%20a%20part,to%20coordinate%20y our%20muscle%20movements

Guy-Evans, O. (2021, April 12). Cerebellum: Functions, structure, and location. Study Guides for Psychology Students - Simply Psychology. https://www.simplypsychology.org/what-is-the-cerebellum.html

Hollomon, L. (2019, January 30). Life without your cerebellum. Medium. https://medium.com/know-your-body/life-without-your-cerebellum-b21e7b976aab

Velioglu, S. K., Kuzeyli, K., & Ozmenoglu, M. (1998). Cerebellar agenesis: a case report with clinical and MR imaging findings and a review of the literature.

European Journal of Neurology, 5(5), 503-506. Warlow, C. (2010). Life without a cerebellum. Brain. 649-654. https://doi.org/10.1093/brain/awq03