Zinn, Zinn, Jason: Intrinsic Functional Hypoconnectivity in Core Neurocognitive Networks

[Woolie]

Why not read about brain networks yourself? You may also want to acquaint yourself of the process by which neuroscience operates.

You're new here, and we're pleased to have you join in. I just wanted to warn you that comments of the type above might give offence. It implies the person you're addressing doesn't know as much as you do and therefore isn't worthy to comment.

Everyone here has a right to comment, no matter how little they know about the area. If you're think they're wrong or ill-informed, then point out why. If you think they don't know s**t about the area, then why not provide a simple explanation of the key points yourself? That way, we share our knowledge and develop a collective understanding.

 

[Woolie]

while they sound impressively 'sciencey', it reminds me of many psychological concepts where they commit the nominal fallacy of naming something but not really explaining it.

There is a definition of sorts, but very few studies bother to explain it.

So to identify the default mode network, you start with a key spot, which is usually in the posterior cingulate (located towards the back of the brain just on the surface where the two hemispheres meet (there's one on each side). Then you plot changes in its activation levels over time, using fMRI, while the person is resting with eyes closed. Then you look for other structures whose changes seem to be "in synch" with the changes in your posterior cingulate "seed" area. That is, you look for correlations in activation across time. Those regions that correlate above a certain level (that you set beforehand) are considered part of the network.

It depends a bit on how where you set your correlation cut-off. But there've been a big bunch of studies now, and most agree the network includes posterior cingulate and surrounding cortcial areas (called retrosplenial cortex), the hippocampus and surrounding regions, the medial prefrontal cortex.

Then comes the messy part, where people start to make inferences about what this network is "doing" while you rest. Memory, visual imagery, thinking and evaluating self are all functions associated with various structures in this network. But they do a lot of other stuff too. This is where it gets all blurry.

In any case, the anatomy of the networks is fairly clear. The function of the networks is still, shall we say "a work in progress"

 

[adreno]

I may be wrong, but, as per @adreno I just wonder what these observations can tell us about the underlying pathophysiology?

I think this sort of research is more of interest to neuroscience than the ME field. It tells us something about how the brain operates under normal conditions vs disease states. As I said before, it doesn't really give any clues to why PWME are sick or what to do about it.

 

[adreno]

I want to add that there is a huge interest in clinical research to identify so-called 'endophenotypes' for diseases. The goal is to describe and understand disease at every level, from the genetic over structural and biochemical to behavioral. This is of course a huge undertaking, and may not even be possible (because of too much heterogeneity).

I do think it is important to understand ME at the functional brain level, although other types of research should probably take priority. At least we now have pretty clear evidence of cognitive dysfunction in ME. If perhaps these functional disturbances can be more closely tied to specific structures and biochemicals in the future, it might provide valuable insights.

 

[alex3619]

I think this sort of research is more of interest to neuroscience than the ME field. It tells us something about how the brain operates under normal conditions vs disease states. As I said before, it doesn't really give any clues to why PWME are sick or what to do about it.

I don't agree for two specific reasons. First, it has the potential to validate our brain fog and similar symptoms. This may mean in time we will not be dismissed so much. Second, it gives us potential markers that may assist in determine if particular treatments are working. All this is still years away though, its early days in this research.

As @Woolie pointed out, the big issue here is false positives. This still plagues a lot of genomic research. In a large data set there can be many associations purely by chance.

These kinds of pilot studies can pave the way for larger and better studies.

On the theme of these findings demonstrating something is wrong, that is all they do, aside from suggesting what symptoms might have a neurocognitive basis. They don't ever tell you why something is wrong, such as what is driving neurocognitive issues. In that I think you are right @adreno.

 

[adreno]

First, it has the potential to validate our brain fog and similar symptoms. This may mean in time we will not be dismissed so much.

It also has the potential to be misused by the BPS school to argue for CBT brain training.

Second, it gives us potential markers that may assist in determine if particular treatments are working.

This technology is way too expensive and cumbersome for routine clinical use.

 

[Marco]

I'm not the only one being somewhat sceptical :

Does the brain have a baseline? Why we should be resisting a rest

Here, we examine the assumptions that are generally made in accepting the importance of the “default mode”. We question the value, and indeed the interpretability, of the study of the resting state and suggest that observations made under resting conditions have no privileged status as a fundamental metric of brain functioning. In doing so, we challenge the utility of studies of the resting state in a number of important domains of research.

http://www.sciencedirect.com/science/article/pii/S1053811906009645

 

[alex3619]

This technology is way too expensive and cumbersome for routine clinical use.

Here its available in a private setting for $300 and it does not take long. Many of us spend that much or more on a single path test, or drug treatment.

 

[alex3619]

It also has the potential to be misused by the BPS school to argue for CBT brain training.

They would argue we should be eating yak fat if a study suggested it, or the psychobabble equivalent.

(Yak fat featured as a quack therapy in a TV comedy show in Australia a long time back.)

 

[adreno]

Here its available in a private setting for $300 and it does not take long.

I seriously question that. These kinds of fMRI analysis are extremely complex and time demanding.

Furthermore, findings from this study (and others) describe averages on the group level, and cannot be applied to individuals. Still too much heterogeneity on the individual level.

 

[searcher]

I seriously question that. These kinds of fMRI analysis are extremely complex and time demanding.

This isn't an fMRI though. It's a qEEG which is quite cheap and often used in private settings.

I agree that this could somehow be used by the BPS school since neurofeedback is often used to improve EEG coherence, I think most often in kids with reading disabilities/ADHD.

 

[jimells]

Why not read about brain networks yourself? You may also want to acquaint yourself of the process by which neuroscience operates. Didn't they say "pilot?"

I have no doubt the Zinns want to do real science. I saw their names on an important letter just yesterday (the latest letter to Lancet?). I'm not a scientist of any kind, so it's difficult for me to learn enough detail, what with cognitive problems and all.

I am always interested in how any new research ideas fits into the evolving political situation. The psycho research crowd is always looking for new non-psych concepts to try to graft their psychosomatic babble onto. Attempts to twist the central sensitization theory for pain into a muddled centralized psychosomatic theory for whatever-they-want-to-treat-with-CBT comes to mind.

When I see the same theory behind both ME research and Borderline Personality Disorder reseach, that looks like something to scrutinize very closely, just to try to understand what the heck is going on.

@siggycat welcome to the forum. Like @Woolie said, every paper and every idea gets close scrutiny. Source references are always welcome. Our unofficial motto could be

In Supreme Beings Some of Us Trust
All Others Bring Data

 

[adreno]

This isn't an fMRI though. It's a qEEG which is quite cheap and often used in private settings.

Right, forgot that. These networks are normally mapped via fMRI. However, I'm still not convinced you can apply this on the individual level. Just because you can show differences between groups on average doesn't mean that everyone with ME will fit into this pattern. Of course, you could treat entire groups and track changes over time.

 

[alex3619]

Furthermore, findings from this study (and others) describe averages on the group level, and cannot be applied to individuals. Still too much heterogeneity on the individual level.

This technology is often used for individual stroke patients to assess their specific damage as far as I am aware.

See for exxample: https://www.uq.edu.au/news/article/2012/08/global-study-shows-brain-damage-stroke-can-be-minimised

This discusses the use of qEEG in acute stroke. We really need that Stanford research on qEEG for ME and CFS before we can really begin evaluating its usefulness.

qEEG is used for neurofeedback, but I have not investigated its efficacy.

 

[Thomas]

I'm not the only one being somewhat sceptical :

Does the brain have a baseline? Why we should be resisting a rest

I'm glad this was brought up. I as a layperson always questioned the brain "at rest" hypothesis as it related to functional neurological testing I have done as part of my ME investigation (SPECT, EEG). In the case of the SPECT, my doctor made sure that I do the first one "at rest" and the second one post exertion. Now; I know what exertion means in ME for the most part, but what is rest? He just meant "not exhausted or exerted" when he said "at rest".

But true "at rest" if there is such a thing would be right when someone wakes up, like in measuring true resting heart rates. My at rest SPECT was performed after I drove 30 minutes, parked, and walked to the hospital section (I was much more functional in 2013 when this was done - but this hardly at rest even for a mild ME patient). Anyways, I'm sort of getting into a philisophical realm here so I'll stop, but I just don't think my abnormal rest SPECT results were all that rested.

 

[alex3619]

e just meant "not exhausted or exerted" when he said "at rest".

For many of us this is a rare event. Exhaustion is the norm.

 

[Woolie]

It also has the potential to be misused by the BPS school to argue for CBT brain training.

Yes, exactly the problem, @adreno!

Just cos it shows up on an EEG or MRI scan doesn't mean it can't be interpreted as psychological. In fact, most neuroimaging work on ME is interpreted in just such a way.

 

[Woolie]

Does the brain have a baseline? Why we should be resisting a rest

Wow, this has gotta be worth a prize for worst pun ever.

PS very interesting article, @Marco!

 

[Woolie]

The psycho research crowd is always looking for new non-psych concepts to try to graft their psychosomatic babble onto. Attempts to twist the central sensitization theory for pain into a muddled centralized psychosomatic theory for whatever-they-want-to-treat-with-CBT comes to mind.

Can I quote you on that first sentence, @jimells? Its a cracker!

 

[Woolie]

But true "at rest" if there is such a thing would be right when someone wakes up, like in measuring true resting heart rates.

Its kind of used as a shorthand for "not responding to an external stimulus or performing a specific task". So to contrast with, say event-related fMRI where you present something to the person (a face or whatever) and they have to respond in some way.

But I agree that there are lots of variables that can affect it, like the ones you mention. Plus alertness/arousal levels, fatigue, mood, pain, the list goes on....