# Predictive-coding and the dissociated brain



## Dr B (Apr 23, 2014)

Hi All. 

OK, this is a complicated one but I'm going to have a go and I hope this is useful / helpful to a number of you. Apologies if you've discussed this before.

There is an emerging theory in the field of neuroscience called 'predictive-coding' and some people (including myself) think it has merit in going someway to explaining a variety of disorders of consciousness. It has also been theoretically applied to experiences in DP/DR. I will try and give a rudimentary commentary here on what its all about - though please note, to understand it more fully will require some further reading.

The brain is like a scientist, generating predictions and comparing those predictions to incoming data from the body and the outside world. Most predictions, most of the time, are confirmed and we have a stable sense of the self. So far, so good. Predictive-coding is a scientific model of multi-sensory processing in the brain. Here, when things are working correctly, all the senses get glued together (as predictions match data and get confirmed) and hopefully provide a coherent sense of self over time. However, this process can breakdown at times and things can go wrong resulting in a variety of disordered conscious experiences - including those reported in DP/DR.

There is something known as 'prediction-error' which kind of pertains to the sensory discrepancy between different sensory sources (and between prediction and confirmation). There will always be some minor error in the system (which is ignored by the brain), but it's important that the brain keeps this to a minimum and can constantly provide sound interpretations / confirmations hundreds of times a second from the multitude on sensory processing constantly taking place.

Here is an example to help illustrate. We are making eye-movements all of the time. The image on the retina is constantly changing, jumping around and highly unstable. However, the world we typically perceive is very stable and not jumping around. How is this done? The argument is that the muscles moving the eyes send a message to other parts of the brain processing the image to overwrite the instability in the image by saying "don't worry, the world is not jumping about, I'm moving the eye and thus it's the eye that is changing the image". This is then used to provide a correction and stable representation of the world out there. So the brain is using predictive information (eye-movements) and feedback from lots of systems to come up with a useful interpretation by supressing and overwriting discrepancy in some systems. You can test this for yourself (though please don't) by moving your eyeball by external means. Here there is no message from the eye muscles, and so the image jumps around a lot and is not over-written by internal predictions. Scientists have done this decades ago with special equipment for moving the eye by external means. That's an example with eye-movements - but the principle, so it is argued, might apply to all bodily signals.

The idea now is that predictive-coding might be able to explain many of the experiences reported in psychosis, schizophrenia and disorders like DP/DR (in different ways as these are very different conditions). Put crudely, if the prediction error is too large, then multi-sensory signals do not get integrated correctly, and do not get 'corrected' and one can feel dissociated from one's body / self-consciousness. The brain has to alter things in order to match the prediction and outcomes - and this results in an altered state. It is vastly more complicated than this, but this is the essence of the approach. I'll add a couple more bullet points to think about.

1 - Emotion and emotional parts of the brain (anterior insular cortex / amygdala) are now seen as crucial for the predictive process.

2- There are concepts known as 'interoception' and 'exteroception' which refer to internal (body) and external sources of information. Inertoception is also thought to be a central emotion process. So emotion is seen by some researchers as being crucial to the predictive process.

3 - Predictive-coding can lead to under-embodiment (DPD) or over embodiment (out-of-body) - these are not the same thing but one model might be able to explain both.

4 - Predictive coding can explain, to some extent, a host of symptoms from DPD by positing an emotional suppression due to under-embodiment. These include; dissociation, feeling disconnected from the body / world, being in a dream, feeling cut off, perceptions lacking emotional colour, a lack of agency over movements and actions, a feeling of no intentions, lack of coordination, brain fog, etc&#8230;

If you're interested in any of the above Google the following search terms:

Predictive coding and dissociation

Interoceptive awareness

Interceptive awareness and consciousness

The predictive brain

Interoceptive awareness

Dont worry if all this sounds complicated - it is. I'll try and pop back and address any questions, but please do carry out some further broader reading.


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## TDX (Jul 12, 2014)

So, if for example only one part of the brain in this network is not working properly it can impair this whole process and so cause the whole syndrome?

It's also interesting that this model claims that under-embodiment is the crucial part. This might also be in line with the model of Sierra and Berrios that claims that prefrontal inhibition of insula and amygdala cause DPD, probably by disrupting this process.


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## Dr B (Apr 23, 2014)

It could cause a type of phenomenology (say feeling disconnectioned from ones own thoughts) and, depnding on where in the system, and its extent, yes it could be extended to a condition or disorder. The issues could be focal and localised - causing mild and temporary instances, or widespread and large, causing more severe symptoms.


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## Dr B (Apr 23, 2014)

Here are some references. Please note, this is by no means an extensive list. I hope its useful. Apologies in advance for formatting jumping all over the place. Its cut n pasted from a paper of mine.

Apps, M. A. J., & Tsakiris, M. (2014). The free-energy self: A predictive coding account of self-rec- ognition. Neuroscience and Biobehavioral Reviews, 41, 85-97. doi:10.1016/j.neubiorev.2013.01. 029

Bechara, A., & Naqvi, N. (2004). Listening to your heart: Interoceptive awareness as a gateway to feeling. Nature Neuroscience, 7(2), 102-103. doi:10.1038/nn0204-102

Blanke, O. (2012). Multisensory brain mechanisms of bodily self-consciousness. Nature Reviews Neuroscience, 13, 556-571. doi:10.1038/nrn3292

Braithwaite, J.J., James, K., Dewe, H., Medford, N., Takahashi, C., & Kessler, K (2013). Fractionating the unitary notion of dissociation: Disembodied but not embodied dissociative experiences are associated with exocentric perspective-taking. Frontiers in Neuroscience. 7:719. [URL=doi:10.3389/fnhum.2013.00719]doi:10.3389/fnhum.2013.00719.[/URL]

Braithwaite, J. J., Watson, D. G., & Dewe, H. (2015; submitted). Predisposition to Out-of-body

Experiences (OBEs) is associated with aberrant emotional responses to body-threats:

Psychophysiological support for interoceptive predictive coding accounts of the disembodied

self. Manuscript submitted for publication.

Clark, A. (2013). Whatever next? Predictive brains, situated agents, and the future of cognitive

science. Behavioral and Brain Sciences, 36(3), 181-204. doi:10.1017/S0140525X12000477 Corlett, P. R., Frith, C. D., & Fletcher, P. C. (2009). From drugs to deprivation: A Bayesian frame-

work for understanding models of psychosis. Psychopharmacology, 206(4), 515-530. doi:10.1007/ s00213-009-1561-0

Corlett, P. R., Honey, G. D., & Fletcher, P. C. (2007). From prediction error to psychosis: Ketamine as a pharmacological model of delusions. Journal of Psychopharmacology, 21(3), 238-252. doi:10. 1177/0269881107077716

Corlett, P. R., Taylor, J. R., Wang, X. J., Fletcher, P. C., & Krystal, J. H. (2010). Toward a

neurobiol- ogy of delusions. Progress in Neurobiology, 92(3), 345-369.

doi:10.1016/j.pneurobio.2010.06.007 Critchley, H. D., Wiens, S., Rotshtein, P., Ohman, A., &

Dewe, H., Watson, D.G., Braithwaite, J.J (in press / 2016) Uncomfortably numb: new evidence for

suppressed emotional reactivity in response to body-threats in those predisposed to sub-clinical

dissociative experiences. Cognitive Neuropsychiatry, DOI:10.1080/13546805.2016.1212703.

Dolan, R. J. (2004). Neural systems supporting interoceptive awareness. Nature Neuroscience,

7(2), 189-195. doi:10.1038/nn1176

Damasio, A. (2003). Feelings of emotion and the self. Annals of the New York Academy of

Sciences, 1001, 253-261. doi:10.1196/annals.1279.014

Friston, K. (2005). A theory of cortical responses. Philosophical Transactions of the Royal Society B: Biological Sciences, 360, 815-836. doi:10.1098/rstb.2005.1622

Friston, K. (2010). The free-energy principle: A uniﬁed brain theory? Nature Reviews

Neuroscience, 11(2), 127-138. doi:10.1038/nrn2787

Herbert, B. M., Herbert, C., & Pollatos, O. (2011). On the relationship between interoceptive aware- ness and alexithymia: Is interoceptive awareness related to emotional awareness? Journal of Personality, 79(5), 1149-1175. doi:10.1111/j.1467-6494.2011.00717.x

Medford, N. (2012). Emotion and the unreal self: Depersonalization disorder and de-affectualiza- tion. Emotion Review, 4(2), 139-144. doi:10.1177/1754073911430135

Medford, N., & Critchley, H. D. (2010). Conjoint activity of anterior insular and anterior cingulate cortex: Awareness and response. Brain Structure and Function, 1-15. doi:10.1007/s00429-010- 0265-x

Seth, A. K. (2009). Explanatory correlates of consciousness: Theoretical and computational chal- lenges. Cognitive Computation, 1, 50-63. doi:10.1007/s12559-009-9007-x

Seth, A. K. (2013). Interoceptive inference, emotion, and the embodied self. Trends in Cognitive Sciences, 17(11), 565-573. doi:10.1016/j.tics.2013.09.007

Seth, A. K., Suzuki, K., & Critchley, H. D. (2012). An interoceptive predictive coding model of con- scious presence. Frontiers in Psychology, 2, 1-16. doi:10.3389/fpsyg.2011.00395

Tsakiris, M., Tajadura-Jiménez, A., & Costantini, M. (2011). Just a heartbeat away from one's body:

Interoceptive sensitivity predicts malleability of body-representations. Proceedings of the Royal Society B: Biological Sciences, 278, 2470-2476. doi:10.1098/rspb.2010.2547

Uddin, L. Q. (2014). Salience processing and insular cortical function and dysfunction. Nature Reviews Neuroscience, 16(1), 55-61. doi:10.1038/nrn3857


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## thy (Oct 7, 2015)

So what's the cure?


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## thy (Oct 7, 2015)

TDX said:


> Sierra and Berrios that claims that prefrontal inhibition of insula and amygdala cause DPD, probably by disrupting this process.


Is the any way of modulating prefrontal inhibition?


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## TDX (Jul 12, 2014)

> So what's the cure?


As I remember how models of depression and OCD are explained to the public, it does not matter which parts of the brain are working wrong, but more which networks are dysfunctional. It may be possible to make these networks functional again, by modulating specific brain areas for example the TPJ. For some people medication might do this depending on what is going wrong. If the placebo effect is negligible (and there is some evidence that this might be the case in DPD), and there are many possible ways how the networks can become dysfunctional, this could explain why many people with DPD respond to different medications. Unfortunately it might not always be possible to improve the situation with medication.

In treatment resistant depression and OCD they are trying to solve the problem by creating in certain parts of the brain a functional lesion with deep brain stimulation to alter network activity. While it's very important to research other possible pharmacological treatments, I think deep brain stimulation is the way to go for treatment-resistant DPD. Other neuromodulation treatments like TMS might be good, too.



> Is the any way of modulating prefrontal inhibition?


I don't know. It might be depend on which neurotransmitters are used for this, but it might be not so simple.


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## Dr B (Apr 23, 2014)

thy said:


> So what's the cure?


I'm afraid there isnt one and indeed, I'm not aware of any cure for any of the major disorders and conditions (Sz, Psychosis, DPD, and so on). However, there are possible treatments that may help alleviate symptoms and improve life quality. Focused rTMS and possible combinations with tDCS might prove fruitful in the future - though lots of work would need to be done on identifying a potent stimulation protocol. There may even be advantages from using specific drugs in combination with stimulation but its very early days.


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## Pondererer (May 18, 2016)

The prediction error makes a lot of sense to me. Would it be fair to assume one can train yourself back to an accurate / more effective predictive coding? Maybe by doing exercises like sensory walk, meditaion etc?


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## Dr B (Apr 23, 2014)

TDX said:


> It's also interesting that this model claims that under-embodiment is the crucial part. This might also be in line with the model of Sierra and Berrios that claims that prefrontal inhibition of insula and amygdala cause DPD, probably by disrupting this process.


There is a brand new paper out by Dewe, Watson, & Braithwaite that makes just that argument!!! Its in the list above.


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## Dr B (Apr 23, 2014)

Pondererer said:


> The prediction error makes a lot of sense to me. Would it be fair to assume one can train yourself back to an accurate / more effective predictive coding? Maybe by doing exercises like sensory walk, meditaion etc?


A truly excellent question and I think its certainly worth a punt - so it may help to strengthen those synapses between intention and action. Its certainly worth a try and makes a good deal of sense on paper. I'm not aware of any studies having done this but its something I've been thinking about for a while

If a flotation tank can make people feel dissociated, then maybe lots of movement excercises can have the opposite effect. Spot on!


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## TDX (Jul 12, 2014)

> I'm not aware of any studies having done this but its something I've been thinking about for a while


Concerning meditation Michal stated that mindfulness meditation (means "mindfulness of breathing") can improve or even take DPD into remission for "a very short time". But there are no clinical trials and in my opinion Michal is a jerk, so his opinion should be treated with caution.



> There is a brand new paper out by Dewe, Watson, & Braithwaite that makes just that argument!!! Its in the list above.


The problem is that it might be beyond the border of my knowledge. By now I am "practising medicine" almost completely based on statistics, but with only a very superficial understanding what might be going on. This is enough to understand the most important things of many DPD papers, but no deep understanding on how things might be working. I thought about reading books about psychology, neuroscience, psychiatry, psychopharmacology and the likes, but I lack motivation and I also do not know where to start.


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## Dr B (Apr 23, 2014)

It can be daunting I know. All I'd say is start with the basics and work from that solid foundation. Learn the principles of neuroanatomy, of structure and function. Then start to specialise in (i reckon based on your posts) neuroscience - in fact, cognitive neuroscience and neuropsychiatry and slowly build. It wont happen over night.

In term of the Dewe paper - whats nice is that the emotional suppression observed was only seen for emotional responses to a perceived threat to the body - there were no correlations in relation to just the background chatter of emotional responding. This is consistent with the notion of a 'threshold' (Sierra and colleagues) and is discussed in terms of predictive-coding. It could be that the threashold is more easily crossed, or is too low in DPD thus resulting in a 'trigger' when it should not. Early days, but nice empirical support for the general contention and unites lots of nice ideas.


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## TDX (Jul 12, 2014)

> It can be daunting I know. All I'd say is start with the basics and work from that solid foundation. Learn the principles of neuroanatomy, of structure and function. Then start to specialise in (i reckon based on your posts) neuroscience - in fact, cognitive neuroscience and neuropsychiatry and slowly build. It wont happen over night.


Indeed it sounds like a lot of work. But I googled a bit and there seem to be Master programs in Germany for neuroscience. I looked at their requirements and they require a degree in "a natural science subject, a biomedical subject, psychology, maths or computer science". That's suprising for me, because I always thought you need a biology or even medical degree. Even a degree in maths (which I have) and in Computer Science (which I nearly had, only the final thesis had to be done) seems to qualify. So the work load for self study would theoretically be equivalent to a 2 year degree. That's much less than I expected, but maybe too high in my situation.


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## thedude47111 (Jul 18, 2016)

Pondererer said:


> The prediction error makes a lot of sense to me. Would it be fair to assume one can train yourself back to an accurate / more effective predictive coding? Maybe by doing exercises like sensory walk, meditaion etc?


Can you explain what a sensory walk is?


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## Pondererer (May 18, 2016)

thedude47111 said:


> Can you explain what a sensory walk is?


Well i prefer it being a comfortable jog with music on the ears. It's basically a walk/jog where you engage all of your senses. Really take a moment to notice the smells, temperature, sounds, all the colours in nature and cars or whatever. Also, using your brain to notice the distance between everything, and acknowlegde shapes / objects. Like i will have a narrative in my head sort of confirming: yes, that is a stop sign, it's about 2meter away from me, with that shape blablabla. Being well aware of your surroundings has a calming effect on the mind.


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## Billy D.P. (Apr 12, 2016)

About three months ago when I had the one-year anniversary of DP and was really thinking hard about a lot of this stuff I remember saying to myself, "This is a disease of the conscious. Whatever area of the brain controls conciseness likely controls DP." Of course I have no idea whether this is true or not and I'm certainly no neuroscientist, but I do firmly believe DP is a malfunctioning of the conscious, the part of the brain that tells you that you are you, that your hand is indeed your hand, that you are a certain age, etc. I believe this is the insula from just basic research but I could be wrong. Either way, this is interesting...


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## Dr B (Apr 23, 2014)

Those who work in the research field of predictive-coding and interoceptive awareness prefer the term "Presence" - which pertains to being in the here and now, and being 'present' in the experience you're having. Consciousness and presence are not the same, more that a sense of presence is something consciousness has. 

It is the sense of presence which is disordered in DP and other forms of dissociation.


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## Dr B (Apr 23, 2014)

With respect, it was NV, no one else who waded in with the term 'bollocks' and then vomited everywhere. All I did was mop up his mess, and I was the one who requested the thread locked as it was going no where, which was a shame considering the conversations I was having with a lot of readers who were very interested.


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## TDX (Jul 12, 2014)

Maybe we should just continue in this thread. For example I asked:

"In the uncomfortably numb paper it says that the subjective experience of emotion results from the recognition of internal bodily states in response to external objects or emotional stimuli and that the intensitiy is dependent on the sensitiviy of internal bodily response.

This is interesting, because it would predict if the sensitivity of bodily responses rises, than so would emotional experience. Maybe bodyscan meditation can increase the sensitivity? Or maybe I should repeat my chain ride experiment at the next carnival and focus on body states?

But could this even work for me? The problem is that the perception of my body is completely normal and there are no feelings of unreality."

Today, I think I overlooked something. The fact that the subjective experience of emotion results from the recognition of internal body states does not preclude that the process could be impaired *after* the recognition of the body state did it's job. Maybe it is a necessary condition, but not a sufficient one. I assume that the experience of emotion is a more complicated process that could be impaired in many possible ways.


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## Dr B (Apr 23, 2014)

ASM said:


> True, he did start it, but you proceeded to argue with him thus continuing it. It takes two to tango, & you've both been warned by the staff to stop!
> 
> At least he was humble enough to make a public peace offering: http://www.dpselfhelp.com/forum/index.php?/topic/55061-predictive-coding-and-the-dissociated-brain-the-debate/?p=378304
> 
> Question is; are you humble enough to accept it?


With respect, it does not take two to tango in this context. I was providing reasoned argument, from an evidence based position, furnished with citations. He was vomitting nonsense, repeatedly factually incorrect, and making sweeping statements. Thus, not a tango as we were not doing the same thing. I hope that's clear to all staff.


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## Dr B (Apr 23, 2014)

TDX said:


> Maybe we should just continue in this thread. For example I asked:
> 
> "In the uncomfortably numb paper it says that the subjective experience of emotion results from the recognition of internal bodily states in response to external objects or emotional stimuli and that the intensitiy is dependent on the sensitiviy of internal bodily response.
> 
> ...


Hi TDX sincere apologies for missing your excellent post and questions. You kind of answer your own question yourself. In the context of DP, predictive coding provides a framework for a number of the experiences like emotional numbing and dissociation. Its not a complete explanation of everything going on, but the central disorders in consciousness. There are papers on 'interoceptive awareness' and 'interoceptive sensitivity' - as they are not the same. Trouble is that debate is a bit muddy at the moment.

Sub-clinicals with DP might not be having an attack, but may well still display a latent bias in processing, thus the conscious and subconscious are doing different things.


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## Dr B (Apr 23, 2014)

It is. But I've not continuued arguing with him here. Yes, I was 'arguing' with him elsewhere, but in the scientific sense (providing a reasoned position to support a conclusion). I find it odd I have to explain this. Again you're trying to tarr us both - when you shouldn't and its not about taking sides. You should not faciliate trolling and that's something admin here will need to think about over time as I'm sure they will.

We wont agree on this - but the matter is over as far as i'm concerned.

Why not set up a section called "Scientific debates" and have clear instructions about the area (i.e., its not for trolling)


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