By Chris Crockford (Editor)
As a researcher in psychology, my days are often spent meeting strangers who have agreed to take part in my research. Mostly it’s an enjoyable experience, and you can meet the most unusual and eccentric individuals. And yet, despite the uniqueness of each encounter, it always begins and ends the same way:
A greeting, a handshake, and a wave.
We all take these simple gestures for granted; these gestures that demonstrate the social nature of human beings; these gestures that communicate cultural values, empathy, and so much more. But more and more often, that which I take for granted is brought firmly into my consciousness when my own physical ability is juxtaposed with a person with motor neuron disease (MND).
The focus of my research is MND, a debilitating and fatal condition. Initially, a person with MND might notice some difficulty working keys, or tripping over because their foot keeps catching on things. But quickly, this small nuisance can spread until the person is unable to walk, unable to speak, and unable to breath. I have met patients, who, within a year of diagnosis, are unable to greet, unable to shake hands, and unable to wave. They have lost the ability to communicate, that so human a gesture.
I think it’s fair to say that MND is awful, but that’s not all. Often when people think of MND, they only think of, or are aware of, the physical symptoms. I don’t blame them; we’re still discovering the complexities of the condition. But what if I were to tell you that around 50% of people with MND will experience cognitive and behavioural difficulties, potentially before any physical symptoms [1]? What if I were to tell you that MND and dementia were opposite ends of the same spectrum, with some people developing both conditions simultaneously [2]?
So we have a situation in which people who develop a debilitating physical disease, have a coin-flip chance of also having difficulties with thinking, even possibly full-blown dementia. The nature of the difficulties experienced by people with MND is varied. Attempts have been made to profile and understand these changes better (my research included), but it’s difficult. It’s difficult when it’s rare, and it’s difficult when, on average, the lifespan of a person with MND is 3 years from symptom onset [3].
Most commonly, people with MND might experience problems with language and executive functioning. Executive functioning is an extremely broad area, but includes higher order cognitive abilities such as planning, problem solving, and social cognition. A person might struggle to listen to a string of numbers and recall them in reverse order; or perhaps a person might struggle to process information regarding social situations, such as the ability to judge another person’s preference through eye gaze (you may be familiar with Theory of Mind, something often lacking in autism) [4]. Difficulties with language have been demonstrated in tasks that require individuals to name an object, or verbal fluency tasks, where participants are asked to say as many words as possible beginning with a certain letter in a given time [5]. However, arguably one of the most striking things that have been noted in MND is a selective loss of verbs [1]. While nouns like ‘hand’ and ‘foot’ are spared, verbs such as ‘grasp’ and ‘kick’ may be lost.
A greeting, a handshake, and a wave.
Verbs imply action. They imply movement. They imply the very thing that sufferers of MND have lost. But in addition to being unable to perform certain actions, they may have also lost the words to describe these actions. Some research has even suggested that sufferers lose the abstract ability to process the representation of actions, such as pictures of actions [6].
A greeting, a handshake, and a wave.
This is strange. We tend to dissociate words from movements (obviously except the movement of our mouths in producing those words). We have a word in our mind that seems to have little to do with our physical body - more so, many consider language and movement to be distinct areas of the brain. But what if they’re intrinsically linked? What if our mind develops as a direct reaction to our physical body? Perhaps this is the opposite of how you thought the brain worked. Rather than our mind developing to control our body, perhaps our body develops to control our mind.
The common belief is that certain brain areas control certain functions and abilities; our hippocampus is important in memory and the corpus callosum allows our hemispheres to communicate with each other. What MND suggests is that perhaps this view of the brain is outdated. Language doesn’t exist in some circumscribed brain region; so is this true of all functions? We are currently in a transitionary period where the focus is now less on where certain functions lie in the brain, and more on the networks that connect. Much like people, areas of the brain don’t exist in isolation. They need to communicate.
A greeting, a handshake, and a wave.
Embodied cognition is the idea that the way in which our mind works is determined by the physical structure of our body – our interaction with our environment [1]. People with MND often do live in isolation. Not only have sufferers lost the ability to perform certain actions, they may lose the ability to say what those actions are, or even think about them. Little gestures that we take for granted can be so much more. They represent a fundamental aspect of being human. They represent how our physical bodies function with our mind and our environment. And they represent what is lost for people with MND. A greeting, a handshake, and a wave become…
A …, a …, and a ….
[1] Bak, T. H., & Chandran, S. (2012). What wires together dies together: Verbs, actions and neurodegeneration in motor neuron disease. Cortex, 48, 936-944.
[2] Giordana, M. T., Ferrero, P., Grifoni, S., Pellerino, A., Naldi, A., & Montuschi, A. (2011). Dementia and cognitive impairment in amyotrophic lateral sclerosis: A review. Neurological Sciences, 32, 9-16.
[3] Elamin, M., Phukan, J., Bede, P., Jordan, N., Byrne, S., Pender, N., & Hardiman, O. (2011). Executive dysfunction is a negative prognostic indicator in patients with ALS without dementia. Neurology, 76, 1263-1269.
[4] Abrahams, S., Newton, J., Niven, E., Foley, J., & Bak, T. H. (2013). Screening for cognition and behaviour changes in ALS. Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, 15, 9-14.
[5] Taylor, L. J., Brown, R. G., Tsermentseli, S., Al-Chalabi, A., Shaw, C. E., Ellis, C. M., . . . & Goldstein, L. H. (2012). Is language impairment more common than executive dysfunction in amyotrophic lateral sclerosis? The journal of Neurology, Neurosurgery & Psychiatry, 84, 494- 498.
[6] Bak, T. H., & Hodges, J. R. (2004). The effect of motor neuron disease on language: Further evidence. Brain and Language, 89(2), 354-361.