Friday, April 13, 2012

Depression - a disease of the mind and of the body

New View of Depression:

An Ailment of the

Entire Body


Scientists are increasingly finding that depression and other psychological disorders can be as much diseases of the body as of the mind.

Shirley Wang on Lunch Break discusses the impact of depression on aging and why people with a history of depression are also known to be at greater risk for cardiovascular disease, diabetes and other aging-related diseases.


People with long-term psychological stress, depression and post-traumatic stress disorder tend to develop earlier and more serious forms of physical illnesses that usually hit people in older age, such as stroke, dementia, heart disease and diabetes. Recent research points to what might be happening on the cellular level that could account for this.


Scientists are finding that the same changes to chromosomes that happen as people age can also be found in people experiencing major stress and depression.


The phenomenon, known as "accelerated aging," is beginning to reshape the field's understanding of stress and depression not merely as psychological conditions but as body-wide illnesses in which mood may be just the most obvious symptom.


"As we learn more…we will begin to think less of depression as a 'mental illness' or even a 'brain disease,' but as a systemic illness," says Owen Wolkowitz, a psychiatry professor at the University of California, San Francisco, who along with colleagues has conducted research in the field.


Gaining a better understanding of the mechanisms that link physical and mental conditions could someday prove helpful in diagnosing and treating psychological illnesses and improving cognition in people with memory problems, Dr. Wolkowitz says.

In an early look at accelerated aging, researchers at Duke University found about 20 years ago that brain scans of older people with depression showed much faster age-related loss of volume in the brain compared with people without depression. The reasons for the accelerated aging appeared to go beyond unhealthy behaviors, like smoking, diet and lack of exercise, researchers said.


Recent efforts to study what is behind accelerated aging on a cellular level have focused on telomeres, a protective covering at the ends of chromosomes that have been recognized as playing an important role in aging. Telomeres get shorter as people age, and shortened telomeres also are related to increased risk of disease and mortality.


In several studies conducted at UCSF, researchers have found shortened telomere length to be associated with depression, childhood trauma and other conditions. A study of 43 adults with chronic post-traumatic stress disorder, whose average age was about 30, and 47 healthy control subjects, found shorter telomere length in the PTSD group that equated to an estimated 4.5 years of accelerated aging, Dr. Wolkowitz says. The study was published last year in Biological Psychiatry.


In separate research, scientists in Sweden found similar results. In a study involving 91 patients with major depression and 451 healthy control subjects, researchers from Umeå University concluded that shortened telomere length was associated with depression and greater perceived life stress. The study was published in Biological Psychiatry in February.


Scientists say more work needs to be done to figure out exactly how severe a psychological experience must be to affect telomere length. Some research suggests that as few as two episodes of major depression may be sufficient to affect cell structure. Other studies indicate that the more bouts of depression a person experiences, the more impact there is on telomere length.


The "holy grail" of this area of work is to try to find the molecular mechanisms by which depression or stress take their toll on the body, says P. Murali Doraiswamy, head of the division of biological psychiatry at Duke University, who isn't involved in telomere work. Such information could help provide clues about how much of age-related disease is due to genetics versus life experience, and whether it can be reversed, he says.


Researchers also want to understand why not all stressed people develop shortened telomeres. Telomere length is thought to be affected by the body's production of certain stress hormones or inflammatory molecules, which are made in greater quantities when people are stressed or depressed. Meanwhile, an enzyme known as telomerase acts to protect against telomere shortening.


Some people appear to have innate biological protective factors, like higher antioxidant level and anti-inflammatory proteins, according to UCSF's Dr. Wolkowitz.


How individuals experience the stress, cope with it and view the world more generally also are thought to relate to telomere length. In 2009, the UCSF researchers found that a personality characteristic, pessimism, correlated with shorter telomeres and increased production of a chemical produced by the immune system related to stress.


In another study, UCSF researchers brought into the lab 50 women and exposed them to standard experimental tasks known to induce stress: giving a speech about their personal strengths and weaknesses and completing a difficult math problem out loud. Some of the women were caregivers for chronically ill children and therefore had presumably more stressful lives. But telomere length didn't seem to depend on whether a woman was one of the caregivers or not. Instead, the telomeres were shorter only in those women who reported greater levels of anxiety about having to perform the experimental tasks—seemingly the ones who tended to get more stressed about life's challenges. The research, led by UCSF postdoctoral fellow Aoife O'Donovan, was published online in March in the journal Brain, Behavior, and Immunity.


Researchers believe it takes months, or even years, for stress or depression to affect telomere length. However, the level of activity of the enzyme telomerase may be affected more quickly. In a pilot study involving 24 patients with prostate cancer, Dean Ornish, founder of the Preventive Medicine Research Institute, a nonprofit research group in Sausalito, Calif., demonstrated that telomerase activity in blood cells increased after three months of changes in the patients' lifestyle, including lowering of cholesterol and psychological distress. Although the study didn't measure telomere length, the researchers suggested that increased telomerase activity in the patients could be signaling greater telomere protection at the cellular level. The study, performed together with UCSF researchers, was published in the Lancet Oncology in 2008.


Heightened telomerase levels have been found in some depressed people who are given an antidepressant. These patients also show improvement in clinical measurements of their depression. Other depressed patients, however, who don't show clinical improvements after being given medication, also didn't experience an increase in levels of the enzyme. The findings are from a small study published in February in Molecular Psychiatry.


After finding that some psychological conditions appear to affect telomere length, researchers at UCSF are trying to find out whether information about what is going on in a patient's cells can be used to change the person's psychology. In an ongoing study, researchers are telling patients how their telomere length, which can be detected through a blood sample, compares with that of an average person of the same age. Researchers are then tracking whether the patients, armed with that information, are more motivated to adopt a healthier lifestyle.

Early Aging

People who have major bouts of depression have an increased risk at a younger age of developing conditions typically associated with getting older. This may be because depression makes cells age prematurely, new research suggests.

•Heart disease

•Atherosclerosis

•Hypertension

•Stroke

•Dementia

•Osteoporosis

•Type 2 diabetes

Source: Owen Wolkowitz, UCSF



Tuesday, March 13, 2012

Bewuste belewenisse _ Breingebeure of meer?

Uit Dr Wilhelm Jordaan se rubriek in Die Burger van 13 Maart 2012

"Nou die aand in die klas sê-vra ’n nagraadse student: “Al ons gepraat oor vryheid van keuse is praatjies vir die vaak, nè? Dis tog duidelik alles wat jy is, word oplaas deur jou brein bepaal.”

Die student beroep hom op onder andere ’n Duitse breinnavorser, Andreas Bartels, van ’n navorsingsinstituut in Tübingen. Dié reken die liefde, byvoorbeeld, is bloot ’n biologiese meganisme en dat ons binnekort seksuele aantrekkingskrag tussen mense chemies sal kan opwek en reguleer. Proewe met diere bevestig dié moontlikheid, sê Bartels. Wat Bartels beweer, is deel van ’n groeiende “neuro-kultuur” wat reken breinkennis kan nou reeds doeltreffend gebruik word om mense se belewenisse en gedrag te bepaal – volgens breinkarterings wat gegrond is op tegnieke soos MRI-, fMRI-, PET- en CAT-skanderings. Die vertrekpunt is dat jou denke, besluite, emosies en gedrag bloot die som van elektriese en chemiese gebeure in die brein is.

Daar is egter breinnavorsers en -kenners, soos die Amerikaner Richard Restak en die Brit Susan Greenfield, wat teen dié “neuro-kultuur” protesteer en tot versigtigheid maan.

Hulle sê ’n behoorlike neurowetenskap kan nie in die isolasie van laboratoriumproewe geskied nie. Weens die ingewikkelde samehang van liggaam (brein) en gees (bewussyn en belewenis) moet die sosiale, kulturele en sielkundige konteks waarbinne die breingebeure plaasvind, verreken word.

Dié samehang behels byvoorbeeld dat ons bewuste belewenisse – al word dit deur elektrochemiese aktiwiteit en oordragstowwe in die brein bemiddel – méér en ánders as breingebeure is; dat oomblikke van intense bewussyn op sigself die breingebeure wysig en selfs nuwe patrone kan skep. Dit sê ’n mens word mens in die volheid van jou belewenisse; en al word hulle elektrochemies “in stand gehou”, is die belewenisse terselfdertyd méér en ánders as breinaktiwiteit en -prosesse.

Lucille Day, ’n neurochemikus, bioloog én digter, beleef die “meer as” van liefhê as ’n “osmose” tussen man en vrou wat sy “sien gebeur” as sy deur ’n elektronmikroskoop kyk na die eenvoud van senuselle wat “ontmoet”. En dan, op die vlak van belewenis, is daar niks meer te verklaar nie. Al wat is, is die gebabbel van die liefde se vreemde tale. Daaruit kom ’n vers:

“flowing inward, they move/toward each other/and when they finally meet,/melding together, cell by cell,/there is no explanation:/they know who they are./I can almost hear them/yammering in strange tongues.”

Dié “méér en ánders” geld in beginsel ook elke ander kosbare menslike belewenis: ’n spirituele ervaring, ’n oomblik van verwondering, ’n poëtiese insig, die bekoring van ’n woordklank, musiek wat ’n katedraal vul, die gegiggel van kinders wat in bome speel, die aanskouing van skoonheid en ’n vredevolle sterwensoomblik... "

Tuesday, May 3, 2011

Behaviour neurologist explains how our brains feel emotion

Interview with behaviour neurologist, Antonio Damasio on how our brains feel emotion.

"An emotion consists of a very well orchestrated set of alterations in the body. Its purpose is to make life more survivable by taking care of a danger or taking advantage of an opportunity."

Question: What is happening in our brain when we feel an emotion?


Antonio Damasio: Feeling of an emotion is a process that is distinct from having the emotion in the first place. So it helps to understand what is an emotion, what is a feeling, we need to understand what is an emotion. And the emotion is the execution of a very complex program of actions. Some actions that are actually movements, like movement that you can do, change your face for example, in fear, or movements that are internal, that happen in your heart or in your gut, and movements that are actually not muscular movements, but rather, releases of molecules. Say, for example, in the endocrine system into the blood stream, but it’s movement and action in the broad sense of the term.


And an emotion consists of a very well orchestrated set of alterations in the body that has, as a general purpose, making life more survivable by taking care of a danger, of taking care of an opportunity, either/or, or something in between. And it’s something that is set in our genome and that we all have with a certain programmed nature that is modified by our experience so individually we have variations on the pattern. But in essence, your emotion of joy and mine are going to be extremely similar. We may express them physically slightly differently, and it’s of course graded depending on the circumstance, but the essence of the process is going to be the same, unless one of us is not quite well put together and is missing something, otherwise it’s going to be the same.


And it’s going to be the same across even other species. You know, there’s a, you know, we may smile and the dog may wag the tail, but in essence, we have a set program and those programs are similar across individuals in the species.


Then the feeling is actually a portrayal of what is going on in the organs when you are having an emotion. So it’s really the next thing that happens. If you have just an emotion, you would not necessarily feel it. To feel an emotion, you need to represent in the brain in structures that are actually different from the structures that lead to the emotion, what is going on in the organs when you’re having the emotion. So, you can define it very simply as the process of perceiving what is going on in the organs when you are in the throws of an emotion, and that is achieved by a collection of structures, some of which are in the brain stem, and some of which are in the cerebral cortex, namely the insular cortex, which I like to mention not because I think it’s the most important, it’s not. I actually don’t think it’s the number one structure controlling our feelings, but I like to mention because it’s something that people didn’t really know about and many years ago, which probably now are going close to 20 years ago, I thought that the insular would be an important platform for feelings, that’s where I started. And it was a hypothesis and it turns out that the hypothesis is perfectly correct. And 10 years ago, we had the first experiments that showed that it was indeed so, and since then, countless studies have shown that when you’re having feelings of an emotion or feelings of a variety of other things, the insular is active, but it doesn’t mean that it’s the only thing that is active and there are other structures that are very important as well.


Recorded July 2, 2010
Interviewed by David Hirschman


Friday, March 25, 2011

About the anti-anxiety benefits of yoga

Strike a Pose to Reduce Anxiety

By Jennifer Gibson, PharmD, practicing clinical pharmacist and freelance medical writer.

Source: BrainBlogger, a biomedical blog that covers topics from multidimensional biopsychosocial perspectives.

Yoga is a practice almost as old as time itself. It combines mental and physical elements that people today use to enhance spirituality, exercise, decrease stress, and increase well-being. While many practitioners of yoga seem almost mystical and more philosophical than the average bear, a new study proves that you need not be a yogi to achieve the anti-anxiety benefits of yoga.

Research published in the Journal of Alternative and Complementary Medicine reports that practicing yoga postures increased the levels of gamma-aminobutyric acid (GABA) in the brain. (GABA is a neurotransmitter in the central nervous system that is responsible for reduced anxiety, increased relaxation, and enhanced muscle tone.) In this study, healthy subjects with no significant physical or psychiatric illnesses or conditions participated in 60-minute yoga sessions 3 times weekly for 12 weeks. Alternatively, a comparison group participated in a metabolically matched walking program for the same length of time. Subjective mood and anxiety measurements were recorded, and magnetic resonance spectroscopy scans were completed at baseline and at 12 weeks.

Overall, yoga participants experienced greater improvement in mood and decrease in anxiety, compared to the walking group. More objectively, yoga participants showed increased levels of GABA in the brain. Positive correlations were observed between improved mood and decreased anxiety and GABA levels. This appears to be the first time that long-term behavioral interventions have produced increased GABA levels. (A similar pilot study showed that a single yoga session increased GABA levels.) Pharmacological agents are frequently used to increase GABA activity in order to reduce anxiety and improve mood. Yoga, in contrast to pharmacological agents, carries almost no risk of adverse consequences and costs very little, if anything, to practice.

In addition to decreasing anxiety, yoga and other mindfulness-based techniques improve stress, depression, overall well-being, neuroticism, eating habits, energy levels, and pain. Yoga has been prescribed for arthritis and other joint and muscle disorders, with strikingly positive benefits. Yoga also promotes immune function, weight loss, decreased heart rate and blood pressure, and muscle strength. Yoga has even been shown to decrease premature delivery when practiced by women during pregnancy. While other forms of exercise bring about the same benefits, yoga has shown more robust benefits than other activities.

With seemingly all the benefits and none of the risks, yoga should be explored as part of a treatment plan for individuals with mood and anxiety disorders. Or, for anyone wishing to improve well-being. So, grab a yoga mat and strike a pose. Namaste.

References

  • Field T (2011). Yoga clinical research review. Complementary therapies in clinical practice, 17 (1), 1-8 PMID: 21168106
  • Haaz S, & Bartlett SJ (2011). Yoga for arthritis: a scoping review. Rheumatic diseases clinics of North America, 37 (1), 33-46 PMID: 21220084
  • Smith BW, Shelley BM, Dalen J, Wiggins K, Tooley E, & Bernard J (2008). A pilot study comparing the effects of mindfulness-based and cognitive-behavioral stress reduction. Journal of alternative and complementary medicine (New York, N.Y.), 14 (3), 251-8 PMID: 18370583
  • Streeter CC, Jensen JE, Perlmutter RM, et al. Yoga Asana sessions increase brain GABA levels: a pilot study. J Altern Complement Med. May 2007;13(4):419-426. PMID: 17532734
  • Streeter CC, Whitfield TH, Owen L, Rein T, Karri SK, Yakhkind A, Perlmutter R, Prescot A, Renshaw PF, Ciraulo DA, & Jensen JE (2010). Effects of yoga versus walking on mood, anxiety, and brain GABA levels: a randomized controlled MRS study. Journal of alternative and complementary medicine (New York, N.Y.), 16(11), 1145-52 PMID: 20722471

Monday, March 21, 2011

Somatic markers - how the body affects the mind

Your somatic markers know when to hold ‘em

By Lorimer Moseley in Body In Mind:Research into the role of the brain and mind in chronic pain, 21 March 2011


There is a very large body of data that show that the body affects the mind. That is, bodily processes and responses to stimuli affect our thoughts about those stimuli and our behavioural responses to them. Some of the most intriguing research in this area has been done by Antonio Damasio – most famously the Iowa gambling project [1]. They have primarily investigated people who have damage to their emotional system – ventromedial prefrontal cortex - yet seem to function very well on language and intelligence tests. They do, however, act in a socially inappropriate manner and make stunning judgement errors. One of the earliest studies showed that while healthy volunteers began to choose advantageously before they worked out which strategy was in fact advantageous, patients with damage to their prefrontal lobe chose disadvantageously the whole time – even if they had worked out which strategy was in fact advantageous. The study also showed that normals would have a galvanic skin response, a sign of sympathetic activation, before they realised they were about to make a risky choice. Damasio’s group has done a bunch of studies that underpin their Somatic Marker Hypothesis – “Somatic markers are events or chemicals in your body, detection of which evokes particular feelings or emotions. A note here that, according to Damasio – check out his very readable book ‘The feeling of what happens’, emotions are brain representations of body states. That is, you see a scary looking man approaching you, your sympathetic nervous system is activated, this sends feedback to your brain and your brain registers this feedback and you feel frightened). So, the essence of the somatic marker hypothesis is that when a “negative somatic marker is linked to a particular future outcome it becomes an alarm bell and when a positive somatic marker is linked to a particular future outcome it becomes an incentive” [2].


So, people who have damage to the part of the brain that registers feedback from the somatic markers, don’t ‘read the signals’ from their internal environment. The somatic marker hypothesis argues that this is why they make errors of judgement and do socially inappropriate things – they can’t process the shift in the somatic markers. So, next time you join the poker game, remember what the somatic marker hypothesis says: it is your body that tells you when to hold ‘em, when to fold ‘em, when to walk away and when to run, not Kenny Rogers. So, clearly there is bottom-up influence on cognition – the embodied cognition people talk about this a great deal. We have shown (see here for BiM discussion on ‘Rubber Hand makes your real hand go colder‘ and visual distortion) a top-down effect of cognitive representations on the body [3, 4]. The next blog will raise the stakes even further, albeit rather speculatively…..

1. Bechara, A. (1997). Deciding Advantageously Before Knowing the Advantageous Strategy Science, 275 (5304), 1293-1295 DOI:10.1126/science.275.5304.1293

2. Damasio AR (1996). The somatic marker hypothesis and the possible functions of the prefrontal cortex. Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 351 (1346), 1413-20 PMID: 8941953

3. Moseley, G., Olthof, N., Venema, A., Don, S., Wijers, M., Gallace, A., & Spence, C. (2008). Psychologically induced cooling of a specific body part caused by the illusory ownership of an artificial counterpart Proceedings of the National Academy of Sciences, 105 (35), 13169-13173 DOI: 10.1073/pnas.0803768105

4. Moseley, G., Parsons, T., & Spence, C. (2008). Visual distortion of a limb modulates the pain and swelling evoked by movement Current Biology, 18 (22) DOI:10.1016/j.cub.2008.09.031

Tuesday, March 15, 2011

On chronic pain and body schema

Pain: The Science and Culture of Why We Hurt

by Marni Jackson

"Why do we still distinguish between mental pain and physical pain," she asks, "when pain is always an emotional experience? Why is pain so poorly understood, especially in a century of self-scrutiny? Hasn't anyone noticed the embarrassing fact that science is about to clone a human being but still can't cure the pain of a bad back?"

A new take on the Gate Control Theory, or, The benefits of rubbing your boo-boos

from the blog of Dave Walton, physiotherapist and Assistant Professor with the School of Physical Therapy at University of Western Ontario.

" ... (I)t is conceivable that the brain's sentry body-self neuromatrix maintains that heightened state of arousal and sensitivity in it's efforts to obtain knowledge about the state of the painful part. This might also be the mechanism behind Peter O'Sullivan's observations that some people with chronic low back pain exhibit behaviours that result in further pain (ie. it's painful to extend the lumbar spine, but some people habitually adopt this posture despite the pain). In that case, this theory would suggest that any stimuli coming from the area, even if unpleasant, can offer at least some form of relief to a neuromatrix seeking information, especially in those conditions that you can't see. Not saying this is good, just saying it makes sense in light of my pseudo-theory. Note that this theory would also support the notion that manual therapies probably have much of their effect through drawing attention to, and providing neurophysiological stimulus from, painful parts of the body. The focus on identifying very specific movement impairments (ie. restricted superior glides of the facet) becomes less of a priority than does identifying the amount of stimulus that can be applied to a body in pain that provides adequate stimuli without being perceived as threatening to the sensitized 'pain' system."

I can't find it! Distorted body image and tactile dysfunction in patients with chronic back pain

By G. Lorimer Moseley

ABSTRACT: The conscious sense of our body, or body image, is often taken for granted, but it is disrupted in many clinical states including complex regional pain syndrome and phantom limb pain. Is the same true for chronic back pain? Body image was assessed, via participant drawings, in six patients with chronic back pain and ten healthy controls. Tactile threshold and two-point discrimination threshold (TPD) were assessed in detail. All the patients, and none of the controls, showed disrupted body image of the back. Five patients were unable to clearly delineate the outline of their trunk and stated that they could not “find it”. TPD was greatly increased in the same zone as the absence or disruption of body image, but was otherwise similar to controls. The disturbance of body image and decrease in tactile acuity coincided with the normal distribution of pain, although there was no allodynia and there was no relationship between resting pain level and TPD. Tactile threshold was unremarkable for patients and controls. These preliminary data indicate that body image is disrupted, and tactile acuity is decreased, in the area of usual pain, in patients with chronic back pain. This finding raises the possibility that training body image or tactile acuity may help patients in chronic spinal pain, as it has been shown to do in patients with complex regional pain syndrome or phantom limb pain.


Friday, March 4, 2011

Ruled by the Body: How Physical Illness Affects the Brain

'Many common ailments and physical conditions can influence the brain, leaving you depressed, anxious or slow-witted.' says Erich Kasten,professor of medical psychology at the University of Lbeck in Germany in an article that appeared in Scientific American on March 3, 2011.

According to Kasten, doctors often forget to ask patients about psychological symptoms. Conversely, psychologists and psychiatrists may treat mental troubles in isolation without looking for a physical cause. But now some doctors and psychologists are reviving the decades-old discipline of somatopsychology, which centers on the effects of physical illness on the brain.

'In Western culture people have long treated body and mind as separate. This dichotomy, popularized by French philosopher René Descartes in the 17th century, is still reflected in medical practice, as the specialists who look after our bodies remain different from those who attend to our psyches. Of course, the division has blurred in recent decades. We now know, after all, that the mind is housed in a physical entity, the brain, which is part of the body. And most people are also aware that psychological problems can produce physical symptoms in the form of psychosomatics; for instance, mental stress can spawn headaches, an upset stomach or even heart problems.

'But fewer people appreciate that the influence also runs in the other direction—that changes in your body can profoundly perturb your mental state,' he says.

Full article available at Scientific American website