I feel, therefore I am
Professor of Clinical Neurosciences and Chair in Physiotherapy Lorimer Moseley provides a fresh take on the link between mind and body.
Meth use and long-term effects on the brain
Sansom Institute researchers are investigating whether chronic methamphetamine use can increase the risk of later developing movement disorders such as Parkinson's Disease.
Five minutes with ...
Dr Antonina Mikocka-Walus
Can cognitive behavioural therapy and hypnosis help people with bowel disorders? Health Horizons chats with Dr Antonina Mikocka-Walus.
Exercise for pleasure - and benefit
Self-regulation of exercise intensity may be a more efficient way to get fit and lose weight than the drill sergeant/boot camp approach. Associate Professor Gaynor Parfitt tells us why.
I feel, therefore I am
by Professor Lorimer Moseley
The mind-body link has fascinated scientists and philosophers for centuries. The link is strong: we now know that visceral cues help us to make decisions - a kind of embodied cognition - and that stress is bad for our health.
The practical take-home messages? Play poker with people with visceral dysfunction because the chances are that they will misread their own bodily cues and you will clean up, and squeeze a yoga session in Saturday mornings to drop your stress levels a bit.
However, a new complexity to the mind-body link has emerged; one that raises the stakes to a new level and suggests that it is not quite as simple as stress management. One way to reflect on the new developments is to compare it to the long-held folk tale that although dogs may look like their owners, eventually, owners begin to look like their dogs.
Let me explain. It is a long-held truth that how our body feels is a reflection of how our body actually is. It is intuitively sensible and is a fundamental of sensory physiology. We feel like we are. Recent evidence suggests, however, that the opposite may also be true - how we feel seems to influence how we actually are. That is, feeling like something is swollen may actually make it a little swollen. The potential implications for this discovery are substantial because how we feel is not simply dependent on sensory input, but is modulated by environmental, contextual and societal factors. But hang on, I am jumping the gun. Let's go back to the start.
We have known for some time that there are a range of clinical conditions that are characterised by disruptions of bodily awareness - the sense of body ownership or the feeling that a body part is distorted or swollen when it is not. There are some conditions in which these distortions are very common - for example some chronic pain disorders involve the feeling that the body part is bigger than it really is; schizophrenia is associated with the feeling that one's body no longer belongs to them and they are separate from it. Intriguingly, many of these conditions, which fall under neurological or psychiatric banners, are also characterised by pain, disrupted thermal regulation or excessive inflammation.
It has been presumed that the disruption of how the body feels and how the body is regulated is probably unrelated; or that the body feels odd because it is not regulated properly. Now we think the opposite might also be true - the body might not be regulated properly because it feels odd.
One investigation into this issue used a well-established cognitive illusion called the rubber hand illusion. It is an easy illusion to induce - one synchronously strokes a rubber hand that the participant can see in front of them, and the participant's real hand, which they cannot see. The brain's predilection of congruent input from across senses leads it to conclude that the stroking one can feel is the same stroking as that which one can see. Like magic, the participant concludes that they can feel the stroking on the rubber hand. A range of studies show that the rubber hand becomes embodied.
Comparatively little attention has been given to what happens to the real hand, the one that sits behind the screen and is, in a way, replaced by the rubber one. It has become clear, however, that there are very real consequences for that hand - it becomes cooler by up to 0.5 degrees, a temperature drop almost certainly involving a limb-specific reduction in blood flow and mimicking the limb-specific reduction in blood flow seen in some of those conditions mentioned above.
The rubber hand illusion has also been used recently to show that the real hand becomes more sensitive to histamine. That is, when healthy volunteers get the illusion and their arms are pricked and histamine is applied, then the area of redness and raised skin that occurs is larger in the arm that has been 'replaced' by the rubber one than it is in the control arm, or in control conditions.
These effects involve manipulating the feeling we have that we own our body. Other work has manipulated the feeling we have that our limb is a certain size. By giving people with painful arms a set of binoculars and getting them to watch the arm as they move it, when it looked bigger than it really is, the increase in pain and swelling that was evoked by movement was greater than when it looked the right size. That is, the movement was identical, but the feeling that the limb was swollen was enough to make it a little more swollen.
These findings are remarkable insofar as they demonstrate that how our body feels to us seems to influence how our body actually is. Consider this then: how our body feels to us is thought by many to be influenced by societal and social factors - one might predict that we feel fatter if we are surrounded by thin people.
Or questions that are closer to my own interests - we know that how our body feels is influenced by the condition we perceive it to be in - is it possible that erroneous beliefs about the condition of our body actually impair its regulation, at a tissue level? On the flip side, might we be able to modify beliefs about the condition of the body to improve blood supply or immune function? Is there a future in modifying the sense of ownership over a body part as a way to increase the brain's rejection of it?
Clearly these are highly speculative questions, but they are not completely outrageous. That neuroscientists are beginning to engage with this possibility is reflected by the recent proposal that attempts to integrate the growing body of experimental and clinical data in this area into a putative model. The model postulates a kind of cortical body matrix - a network of brain circuits that is responsible not only for the physiological regulation of our body, but also for the way it feels, the sense we have that we own it, and for surveillance of our body and the space that surrounds it.
The neurology of this cortical body matrix will be very hard to untangle, but there are clearly strong connections between the individual brain areas to which these individual functions have been attributed. For example, the insula cortex, a brain area that is critical for regulating blood flow, receives direct projections from brain cells in the posterior parietal cortex that are critical for mapping the anatomical location of a sensory stimulus and integrating it with a space-based coordinate system, as well as brain cells in the prefrontal cortex that are critical for giving us the sense of ownership over a body part.
We are obviously at the beginning of this line of enquiry, but there seems no doubt that Descartes was right - we are indeed so firmly held within our body that we are in fact one with it. One might suggest that we now need to move beyond the general notion that stress affects our health and embrace a much more complex interaction between mind and body. It may well be that you are what you think you are.
Meth use and long-term effects on the brain
It is well documented that methamphetamine use can lead to psychosis, brain damage, violent behaviour and crime, but researchers at the Sansom Institute are now investigating whether chronic use can also increase the risk of later developing movement disorders, such as Parkinson's Disease.
Australia has among the highest rates of methamphetamine use in the world, and the long-term implications for our health system are not fully understood, but likely to be significant. Not to mention the social impact of the drug and the high rate of illegal behaviour among chronic users.
Led by Professor Jason White, Dr Chris Della Vedova and Associate Professor John Hayball, all of the School of Pharmacy and Medical Sciences, the research is particularly interested in whether immune system changes lead to damage to the substantia nigra that are associated with methamphetamine use.
The research focuses on the substantia nigra as it is the area of the brain that is important for voluntary movement, and, importantly for a study such as this, its morphology can be observed in conscious people with non-invasive ultrasound.
Funded internally under the Research Development Grant Scheme, the researchers are focusing on three groups of subjects - chronic methamphetamine users, a cannabis users control group, and a non-drug users control group. As Dr Della Vedova explains, the second group is needed because many methamphetamine users also use cannabis. This control group will ensure that any changes to the substantia nigra are not due to cannabis use.
With the assistance of Dr Gabrielle Todd, senior research fellow with expertise in neuroscience, the researchers have begun to study ultrasounds from some of the participants and are already seeing some differences in the methamphetamine users' group.
Dr Della Vedova says it appears likely that methamphetamine use had a high correlation with inflammation in the substantia nigra.
He says the research has the potential to lead to a clearer understanding of the long-term effects of methamphetamine abuse and might lead to improved treatment and/or prevention strategies.
"Meth is a nasty substance and the body responds to it in the same way as it responds to other nasty substances - that is an inflammatory response. Our hypothesis is that this inflammation causes the changes to the substantia nigra."
He suggests this might indicate that anti-inflammatory drugs could help treat methamphetamine addiction, and reduce the chances of relapsing.
"If you have an addiction to heroin, there's methadone, and for alcohol addiction, there's acamprosate or disulfuram, but if you're addicted to meth, there is no replacement drug. The relapse rates are high and this research can potentially help find better pharmacological options for treatment."
People use methamphetamines for a variety of reasons. As a stimulant, it is used as an appetite suppressant, or to stay alert for study, work or social reasons. It's often the drug of choice among women trying to lose weight, students at exam time, and, as has been well-reported, long-distance truck drivers.
"Chronic users often start for an innocuous reason," Dr Della Vedova said, "but it is quite addictive, so they can't stop."
Previous longitudinal studies suggest that methamphetamine users are more likely to suffer from movement disorders later in life, but this is the first time the research has attempted to pinpoint the mechanism behind it all.
Five minutes with ...
Dr Antonina Mikocka-Walus
A registered psychologist with an interest in psycho-gastroenterology, Dr Antonina Mikocka-Walus has produced a fascinating body of work highlighting the brain-gut connection.
You are examining how psychological interventions such as cognitive behavioural therapy (CBT) and hypnosis may be used to manage chronic conditions of the gastrointestinal tract. How did this interest come about and what do you hope the research will achieve?
This research interest came from my family history of these conditions. I have experienced and observed how people around me (including myself) have struggled with these conditions and wanted to do something to help my family but also other suffers worldwide.
Since I am a psychologist, initially, I wanted to simply understand in what way a chronic disease such as inflammatory bowel disease (IBD) impacts on mental health and quality of life. My doctoral research demonstrated a significant emotional impact of the physical disease on everyday life and I have started designing psychological interventions to help patients cope with the disease.
Interestingly, in the last couple of years studies started to show that by helping patients deal with the emotional side of the disease we can actually also better manage symptoms or even delay disease progression. I am hoping to demonstrate this in my current randomised controlled trial using cognitive-behavioural therapy to manage IBD symptoms. In this study, for a period of 18 months, I observe changes in inflammation and disease activity under the influence of a 10-week psychotherapy program.
The trial is still in progress but the trends towards reduced disease activity and improvement in mental health are already clearly noticeable. This is the largest trial of its kind world-wide and I am hoping what I show will change the practice in gastroenterology towards incorporating psychological support in the standard care.
What do we know about the brain-gut connection?
By talking to patients who have gastrointestinal conditions it becomes quite apparent that stress triggers symptoms. In fact, one does not have to have a chronic gastrointestinal diagnosis to know that our stomachs are quite sensitive to changes in our emotional wellbeing. Many people report frequent visits to the toilet before exams or overseas trips. Some people report nausea and stomach tightness and some may even vomit when faced with a stressful situation. Over the past 20-30 years more and more studies have been documenting this co-morbidity.
My contribution focuses on the relationship between mental health status and physical symptoms in inflammatory bowel disease. In the early to mid 20th century researchers thought of it as a psychosomatic condition but this concept was later rejected when it became clear that stress does not lead to IBD. So for the last 50 years of the 20th century IBD was considered to be a purely biomedical condition.
IBD is an autoimmune disease. We are still not sure what causes it but genetic and environmental factors are most commonly implicated. Only in the last 10 years observational studies started to examine the role of stress and depression and their impact on IBD and showed that even though mental health problems do not lead to IBD, they have an impact on the disease course. Thus, patients who relapse often have more stressful events in their life. IBD patients who are depressed are more likely to have an IBD relapse than those with good mental health.
My personal theory is that it is not stress itself causing the worsening of the disease but the inability to cope with it in an adaptive way. I have met many patients who have had very difficult lives and yet their disease was very well controlled. The difference is in the way they cope with stressful situations. Cognitive-behavioural therapy teaches people how to do it well and that’s why I hope the trial I am conducting will show that one can delay disease progression by improving their coping with stress.
Tell us about your PhD research, which explored the relationship between mental health status and clinical outcomes in patients with inflammatory bowel disease, irritable bowel syndrome and chronic hepatitis C
The research showed that individuals suffering from these conditions have much poorer quality of life and higher rates of depression and anxiety than the general population. Because of the high prevalence of these co-morbidities, and particularly anxiety, it was recommended that these patients should be treated by interdisciplinary teams rather than gastroenterologists alone.
The thesis also showed that there is a lack of evidence-based psychotherapies for these patients and that’s why my post-doctoral work has been on developing such therapies. Another aspect of this thesis was exploring the role of antidepressants in IBD and the thesis showed encouraging results indicating that antidepressants (in a similar way to psychotherapy) may have a potential to reduce disease activity in IBD, however, more research was recommended to confirm these observations. I conducted a retrospective study on the use of antidepressants in IBD and also interviewed patients about this proposed line of therapy with encouraging results.
What direction will your work take next?
My future plans are two-fold: I want to look into other options - such as antidepressants and hypnotherapy - that may help chronic sufferers; and with respect to psychotherapy, I also want to investigate smarter options for reaching people such as booklets and online tools.
I would like to find out if some antidepressants have anti-inflammatory properties that are comparable to those of the current anti-inflammatory treatment and thus possibly offer new treatment options for IBD sufferers.
And there is already research that shows that stress, depression and mental health have an impact on the relapse of IBD, so hopefully, if sufferers can become immune to stress, then the progression of the disease may be able to be stopped or delayed. This may be done either through psychotherapy or with the use of antidepressants.
And then the next step is to research whether hypnotherapy could help treat these disorders. I haven't started designing that research yet, but it is in my mind and small studies from other groups worldwide show that hypnotherapy may reduce inflammation in the bowel and may improve disease course, but these are mostly not well controlled studies and more research is needed.
I have started testing online therapies and am working on developing some short CBT tools such as booklets. One of the problems of standard face-to-face therapy is that people don't continue for the required period of 10-12 weeks - they have busy lives, work commitments or young families and can't always get to weekly sessions. So we need to find other novel ways of reaching them so that CBT is widely available to anyone who is interested in it.
You have had an interesting journey to becoming a psycho-gastroenterology researcher, including stints as a journalist and translator in your native Poland. How did this experience complement your work as a researcher?
They both equipped me with useful skills I use every day. Journalism taught me how to do research, critique it and write succinctly. My language skills are useful while reading research papers in foreign languages but also establishing collaborations with international partners. I think reading and speaking in a few languages makes research work much easier and opens up possibilities for conducting international studies. Also I really enjoy learning languages and am currently spending a lot of my free time studying French and German. This proved handy during my latest research trip to several centres worldwide with similar interests to mine.
Exercise for pleasure - and benefit
To the layperson, it seems fairly obvious that people are more likely to stick to an exercise program that is pleasurable, but researchers at the Sansom Institute are going a step further - they hope to prove that self-regulated exercise has a better long-term effect on health than an exercise program prescribed to achieve a specific work rate.
Associate Professor in Exercise and Sports Psychology, Gaynor Parfitt, is leading a team examining how affect-regulated exercise regimes provide an alternative and viable approach for exercise prescription. Put simply, affect-regulated exercise programs use a scale from -5 (very bad) to +5 (very good). So, if a person is told to exercise to feel 'good' (+3 on the scale) they will exercise at a lower intensity than if they are told to exercise to feel 'fairly good' (+1 on the scale).
Research so far with sedentary and active participants has shown that when allowed to regulate their own intensity, participants will often work at the same level typically prescribed in an exercise program - but feel more pleasure and therefore be less likely to drop out of the program.
"Individuals will choose to do, and repeat things that they enjoy. Given choice, you wouldn't go back to the same restaurant, if you didn't enjoy the meal! It's the same with exercise," Associate Professor Parfitt said.
Affect-related exercise programs can be particularly useful for people who are currently sedentary, but want to change their behaviour, or for those recovering from an accident or after a heart attack or stroke.
Associate Professor Parfitt said that it is important to maintain a feeling of pleasure when exercising, and when it stops being pleasurable, rehab patients need to rest or reduce the intensity.
"The brain wants to maintain a balance, so if you over-exert physically, the brain will tell you. If you are in control, you make these adjustments - like changing the speed or incline of a treadmill. It may not even be a conscious decision."
She compared rehab exercise programs with taking medicine, or crash diets, in that many patients stop once the prescribed period ends (or they lose the required weight). But with self-regulation, they are more likely to stick to the regime in the longer term. This is the focus of current studies, which are going to track participants after an eight week program.
She also stressed it was not about going to the gym, or being an elite athlete. For rehab patients, or the sedentary, regular activity: a brisk walk to the letterbox, or around the block, can have a positive effect on health, and can lead to long-term behavioural change.
"It's about people feeling able to do the exercise - and knowing that they can choose to stop. If you get the psychology right, the physical stuff will take care of itself."
The American College of Sports Medicine's position on prescribed exercise was that it had to be "effective and safe". The recently update position statement has just acknowledged the work of Associate Professor Parfitt and colleagues to recognise the potential role that pleasure and enjoyment may play in exercise adherence.
This update indicates the need for additional evidence before affect-regulated exercise can be recommended as a primary method for exercise prescription. Associate Professor Parfitt hopes that her research will provide this evidence.