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... "

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

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.

The Green Fuse - Embodiment Resources

Dr Adrian Harris bedryf 'n interessante webwerf m.b.t. beliggaming of embodiment. The Green Fuse lys 'n klompie definisies van die konsep sowel as skakels en 'n uitgebreide bibliografie oor die onderwerp.

Sy eie navorsing handel oor beliggaming in eko-paganisme, 'n heedendaagse beweging wat hulle spiritualiteit uitleef deur omgewings aktivisme en rituele. Hy ondersoek ook beliggaming in religie en eko-teologie, filosofie en die natuurwetenskap.

Die moeite werd om te bekyk.

Dr Adrian Harris maintains a very interesting website that focuses on embodiment. The Green Fuse contains definitions of the concept as well as links and an extensive bibliography.

His own research looks at embodiment in eco-paganism, a contemporary movement in which pagans express their spirituality through environmental activism and rituals of resistance. He investigates embodiment in religion, ec0theologie, philosophy and science.

A site worth visiting.