"The single biggest predictor of rate of Parkinson's progression is if you answer true to 'are you lonely'?"
This finding by Dr Laurie Mischley, who monitors the progress of symptoms of more than 1500 people with Parkinson's Disease,
is perhaps one the most tragic aspects of the disease in our modern society, in which we people with PD may find ourselves heading toward this outcome by default. Indeed, I have lost count of the number of people with PD who have said something to me along the lines of "my friends and family have abandoned me/don't visit/lost touch". The negative feedback loops between loneliness and disease progression can be one of the most vicious circles of PD. I speak from personal experience also, because at my lowest point, I too had become very isolated, virtually alone in the house and barely going out.
This issue runs much deeper than simply being due to people in pain naturally pushing others away and wanting be alone, or otherwise healthy people naturally feeling uncomfortable or awkward around someone who is chronically ill. To understand the deeper root causes of estrangement and isolation in Parkinson's Disease, we need to first understand some background about the biological evolution and neuroanatomy of the human nervous system.
The following is adapted from
The Pocket Guide to the Polyvagal Theory: THE TRANSFORMATIVE POWER OF FEELING SAFE.
For a collection of peer reviewed technical science articles on this by Dr Stephen Porges and co-workers, see also
The Polyvagal Theory: NEUROPHYSIOLOGICAL FOUNDATIONS OF EMOTIONS, ATTACHMENT, COMMUNICATION, AND SELF-REGULATION.
The vagus is a cranial nerve that emerges from the brainstem.
We have twelve cranial nerves, and some of them control the muscles of the face.
Cranial nerves are not equivalent to the nerves emerging from the spine that control the skeletal muscles of the limbs.
Facial expressiveness, the middle ear, the neck and the voice are regulated by cranial nerves emerging from the brain, distinct from the spinal cord regulation of the limbs and torso.
The vagus nerve, however, is involved not only with the regulation of facial muscles, but also the cardiac and pulmonary muscles - heart and lungs.
The vagus nerve therefore is a two-way communication channel connecting the face to the organs, and the body to the brain.
It allows brain function to affect the visceral organs and vice versa.
It links the regulation of the heart to that of the facial muscles.
Enables our inner physiological state to be written our faces and to be heard in our voice.
Enables changes in our facial expression or tone of voice to affect heart/breathing rate.
Many health problems are known to include both poor regulation of the heart and dampening of facial expressiveness, vocal range, auditory hypersensitivities, and stiff neck.
These health problems are connected with loss of ability of the vagus to regulate the muscles which it supplies.
This heart-face integrated system comprises a evolutionary purposeful "social engagement" system, allowing humans (and other mammals) to work together in social groupings.
This social engagement is downregulated/inhibited in those conditions which include expressionless faces, auditory and language, and neck/shoulder problems as symptoms.
A damped social engagement system is bilaterally associated with increased fight-flight or freezing behaviors.
When this system is damped early in life, it can lead to significant developmental problems.
The above is tremendously important for people affected by Parkinson's Disease to understand in terms of their own health, since PD is a condition so highly associated with a blank or expressionless face, weakened vocal abilities both in terms of volume and emotional content, lack of ability to move head, and issues with listening. Indeed, these are all classic symptoms of PD, which get worse as the disease progresses.
However, even more important is in understanding the resulting impacts of these features of the disease on other people and hence on social interactivity, due to the profound implications for social isolation, Again, the following is adapted from Dr Stephen Porges' works on the polyvagal nervous system.
Neuroception is a process by which our nervous system evaluates risk without requiring conscious awareness nor cognitive evaluation.
Automatic programs involving parts of the brain which are constantly checking for cues of safety, danger or threat.
These processes can then shift our internal physiological or emotional states according to the real time outcomes of their evaluation.
Although we may not even be aware of specific cues which cause a particular change in state, we may be aware of the resulting shifts in internal state, e.g. changing heart rate, gut feelings or sensations, an intuition.
Our evolutionary survival actually depends more on these visceral instincts which reside in the structures of our nervous system, than on our cognitive or conscious self-awareness
The evaluations however are highly individual, and that which some people's system detects as safe and comfortable, others detect as risky and frightening.
People with faulty neuroception detect threat/danger when there is none or feel safe when danger is actually present.
This component in our nervous system, which is meant to be self-protective, also allows us to evaluate the states and feelings of other people.
Through neuroception, our bodily functions act like a lie detector, which is not always correct.
We are highly tuned to the physiology and intentions of others through their facial expression, vocal tones and volume, gestures and posture, and how these, in turn unconsciously make us feel.
When neuroception detects safety in another person, it can also trigger internal physiological changes, such as hormonal ones, which translate to trust, social interaction and relationship building.
Different physiological or emotional states can therefore be identified with optimal social behaviour or efficient, adaptable defensive states, or dysfunctions of these.
From this perspective many health issues and dis-eases can actually be understood as problems with neuroception and atypical behaviours from nervous system [dys]regulation resulting in difficulties turning off defensive strategies ["stress"] or disabling spontaneous, normal social interactions to occur.
Challenges current social and healthcare models, such as schools, hospitals, institutions, as these may be inadvertently set up to trigger unconscious feelings of danger and threat especially in sensitive, traumatized or unwell people, e.g. low frequency background noises, types of lighting, demeanours, attitudes and atmospheres.
However, also points to new strategies based on "neural exercises" which regulate faulty neuroception, such as the "Integrated Listening System", or the neuroplastic techniques covered in Dr Norman Doidge's book "The Brain's Way of Healing".
We currently do not account at all for how these social engagement and neuroception aspects of our neuroanatomy affect the real life experiences of people with Parkinson's Disease. This is unfortunate, since to re-iterate, the social engagement functions are significantly downregulated in people with PD through atrophy/inhibition of the cranial nerves (both sensory and motor): facial expression, volume and emotion in voice, light in the eyes, natural movements of the head, ability to listen, all become dulled/inhibited/absent as the disease progresses. The important point to stress is this lack of social information and of the normal social signals emanating from people with PD will trigger unconscious and automatic responses in other humans. Indeed, the facial and vocal "masking" in people with PD will tend to set off the neuroception in others, creating sensations of unsafety in their nervous system, simply because the person with PD isn't giving out the "normal" social or externalized cues that their biology expects. This results in a "threat" type response in other people via the hardwired nature of the evolutionary biology of their neuroanatomy. It is extremely important to stress this is not about other people doing anything wrong or being to blame or even conscious of this, it is about unconscious automatic response hard wired into the human nervous system, for extremely good evolutionary reasons for our own survival.
Conversely, inhibition of the social engagement nervous system, due to atrophy of cranial nerve function, means people with PD also often can't read the social engagement cues of others correctly. This, in turn, may result in inappropriate interruption of normal social interactions or the misreading of the physiological or emotional states of other people. Again, it is to be stressed that this is not done on purpose, and is without attached blame, usually occurring without the person with PD even being conscious of it. This unconscious breakdown in normal social graces and responses can also lead to estrangement and further social isolation. Porges even has a term for this: "biological rudeness", which he defines as
"a cascade which starts with a lack of reciprocity to a spontaneous social engagement that triggers an automatic state of defence and ends with an emotional response of being offended that may lead to an aggressive reaction."
A very clear demonstration of this reflexive aspect of the human nervous system is given by the famous "Still Face" experiment with infants.
It is my hope that through having increased awareness of our own biological reactions, we can all begin to understand the challenges that people with conditions like Parkinson's Disease face in social interactions every day. Again, people with PD may have combinations of all these features present a lot of the time, including unreadable faces, reduced voice content, and lack of animation. In pointing people to their own inherent visceral reactions to these types of symptoms, I hope we, as a society, can acquire an increased understanding and, more importantly, increased compassion, towards people with Parkinson's Disease as they attempt to manoeuvre through a very difficult terrain of social interactions, which is currently strongly stacked against them.
For more information on these topics, see: