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... "

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

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

The brain isn’t going to take it lying down

The brain isn’t going to take it lying down in Mind Hacks

The brain may manage anger differently depending on whether we’re lying down or sitting up, according to a study published in Psychological Science that may also have worrying implications for how we are trying to understand brain function.

Anger experiments that have measured electrical signals from the brain (using EEG) or that have altered neural activity with magnetic pulses (using TMS) have found that the left frontal lobe is more active than the right, but studies using fMRI functional brain scans have found no differences.

Psychologists Eddie Harmon-Jones and Carly Peterson wondered whether the brain might be working differently in EEG and TMS experiments because the participant is usually sitting upright, while in fMRI, the person is usually lying flat on their back.

If this seems like a trivial distinction as far as emotion is concerned, it actually has some sound theory behind it. A field of study called 'embodied cognition' has found lots of curious interactions between how the mind and brain manage our responses depending on the possibilities for action.

For example, we perceive distances as shorter when we have a tool in our hand and intend to use it, and wearing a heavy backpack causes hills to appear steeper.

Anger is a prime example where we feel motivated to ‘do something’. In the sitting position we’re much more ready to approach whatever’s annoying us than when we’re flat on our backs, and the researchers wondered whether these body positions were interacting with our motivations to change the brain’s response.

So Harmon-Jones and Peterson asked 46 participants to write a short essay before wiring them up to an EEG that measured the electrical activity across the brain.

The participants then put on headphones and listened as someone else read their essay and rated the author on personal characteristics, such as intelligence and competence. Some participants listened while lying down, others while in the sitting position.

What they didn’t know was that the ‘raters’ were actually pre-recorded audio, and while some heard a benign commentary on their work, other participants heard the other ‘person’ slagging-off them off and harshly rating the participant and their personality.

In line with the ‘ready to respond’ theory, when the participants were angry and sitting up, the left frontal lobe was much more active than the right – but when angry and lying down, there was no difference.

First off, the findings provide evidence that body position interacts with how the brain processes emotion, perhaps depending on which actions are immediately possible.

But more importantly, the experiment might also indicate that different neuroscience techniques may be throwing up varying results because of the differing body positions needed to take the tests.

Although this is only an initial study, it could be a major spanner in the works for cognitive science which often assumes that clumping together evidence from a whole range of techniques gives a better idea of what’s going on.