Higher-order brain processes, rather than early processing, underlie sensory problems in ME/CFS: Evidence from ERPs, 2026, Kumar et al

forestglip

forestglip

Administrator
Staff member
Higher-order brain processes, rather than early processing, underlie sensory problems in ME/CFS: Evidence from ERPs

Sanjay Kumar, Alfred Veldhuis, Farzaneh Yazdani

Introduction
Patients with Myalgic Encephalomyelitis (ME)/Chronic Fatigue Syndrome (CFS) experience significant sensory problems that affect their personal, social and occupational life. However, there is no clear understanding of how the sensory problems manifest in ME/CFS. Neuroimaging studies have provided indirect evidence of the involvement of sensory brain areas in ME/CFS. This novel systematically examined the role of early sensory processing and late information processing brain systems in ME/CFS patients.

Methods
The participants consisted of 31 ME/CFS patients and 30 healthy matched controls. Measures of subjective experience of sensory problems as well as event-related brain potentials (ERPs) on an auditory paired click task and an auditory oddball task were collected.

Results
ME/CFS patients reported significantly higher sensory problems compared to the control group. On the ERP measures, the ME/CFS group was not significantly different on the P50 suppression index than the control group. However, the ME/CFS group showed a significantly reduced P300 potential compared with the control group.

Discussion
These findings suggest that the higher-order control-based brain mechanism contributes to the sensory problems experienced by ME/CFS patients. These findings could have profound implications for targeted interventions directed towards higher-order brain systems, rather than the sensory systems, to address challenges related to sensory processing problems in ME/CFS.

Web | Frontiers in Medicine | Abstract only ahead of publication

Edit: Now published: Web | DOI | PDF
 
Last edited:
Had a little walk with AI since I’ve never heard of this before, but apparently the P3a test and a P3b where P3a is driven by dopamine, bummer they didn’t stratify into this, sounds like they need to do a different buzzer test to get that stratification. I’ll have to read more about this. Having just heard about this I could be totally off base.

It makes me wonder if the eMSNs play a role in this part of the brain as a filter
 
Hmmm, is this possibly an effect of reduced activity:

“Compared to a control group, bed rest participants showed significantly decreased P300 and LPP amplitudes to pleasant and unpleasant stimuli, especially in centroparietal regions, after 30 days of bed rest”

(PDF) Electrocortical Evidence for Impaired Affective Picture Processing after Long-Term Immobilization
https://www.researchgate.net/public...ure_Processing_after_Long-Term_Immobilization
 
This is where the interpretation problem gapes open and threatens to make such studies unusable. But maybe cross comparison of a range of situations and cohorts would allow us to make sense of it. I think it addresses a crucial question, of direct relevance to people like James, wanting to know where in the brain the DecodeME gene variants might be tweaking the system and where to target those genes in experimental systems in the lab.
 
Several factors can influence the P300’s characteristics. Influencing factors are stress, anxiety, and attentional level [4,9,10]. Moreover, external factors such as body temperature, sleep quality, exercise levels, dietary intake, coffee, and drug use, can influence the P300 [5,11].

Furthermore, the amplitude of P300 can be affected by the specific properties of the oddball paradigm [5]. If the stimulus has been presented more often, participants can become more familiar with it, leading to a lower amplitude. Similarly, if an auditory stimulus is presented louder, it may be easier to distinguish the target from the background stimulus resulting in a lower amplitude, as there is less cognitive effort necessary.
Click to expand...
www.tmsi.artinis.com

TMSi — an Artinis company — What is the P300 in Event-Related Potentials (ERPs)?

This blog describes what the P300 is and how you can detect it. It includes a practical example of how a P300 response was measured using TMSi's SAGA, including the experimental protocol, a sample dataset, and all acquisition and processing codes. At the end of this blog, you will be able to downloa
www.tmsi.artinis.com www.tmsi.artinis.com

It might be doable to measure this at home, I can find websites for ambulatory EEGs. That would allow comparison between mild/moderate and severe.
 
"Higher-order brain functions are complex, sophisticated mental processes—such as reasoning, memory, and language—that go beyond basic sensory perception and motor control. These conscious and unconscious processes largely occur within the cerebral cortex, relying heavily on advanced, abstract information processing in the Cerebral Cortex and Higher Cognitive Functions."

Several studies have ME/CFS patients have found evidence of reduced cerebral blood flow
https://me-pedia.org/wiki/Brain#cite_note-Natelson,_2017-11
https://me-pedia.org/wiki/Brain#cite_note-Costa1995-12
https://me-pedia.org/wiki/Brain#cite_note-Barnden2011-13
https://me-pedia.org/wiki/Brain#cite_note-Biswal2011-14
https://me-pedia.org/wiki/Brain#cite_note-Yoshiuchi2006-15
https://me-pedia.org/wiki/Brain#cite_note-16
https://me-pedia.org/wiki/Brain#cite_note-17
https://me-pedia.org/wiki/Brain#cite_note-18

Brain-regional characteristics and neuroinflammation in ME/CFS patients from neuroimaging: A systematic review and meta-analysis

pubmed.ncbi.nlm.nih.gov

Brain-regional characteristics and neuroinflammation in ME/CFS patients from neuroimaging: A systematic review and meta-analysis - PubMed

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating condition characterized by an elusive etiology and pathophysiology. This study aims to evaluate the pathological role of neuroinflammation in ME/CFS by conducting an exhaustive analysis of 65 observational studies...
pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov
 
Last edited:
The OMF multimodal brain imaging study just released some preliminary data that seems to converge with earlier fMRI findings pointing toward the Default Mode Network as an area of interest. Seems ME brains might be stuck in the introspective rest cycle struggling to turn off the Default Mode Mode Network to switch to broad and more effective activation.

I’m wondering whether that fits the picture presented in this study but I’d guess so. Impaired activation means impaired stimuli response, right?

Not knowledgeable enough on this topic to be quite sure of that overlap but it seems logical.
 
There is an awful lot of processing between 50msec and 300msec. My experience from research into P300 and conscious recognition events is that nobody really knows what these signals correspond to. I think there is plenty of room in the 'unconscious' events of the basal ganglia for an effect on P300. And quite often it turns out that results like this are more about the way people respond in an artifactual test than any normal activity.
 
Violeta said:
Several studies have ME/CFS patients have found evidence of reduced cerebral blood flow
Click to expand...
It would be interesting if they looked at the difference between ME/CFS patients sitting upright versus laying down. When I am deep in PEM, even just sitting upright feels really difficult, and I’m sure that my cognitive abilities would be at least a little impaired. It doesn’t sound like they included orthostatic intolerance as part of their study though.
 
SugarSquared said:
It would be interesting if they looked at the difference between ME/CFS patients sitting upright versus laying down. When I am deep in PEM, even just sitting upright feels really difficult, and I’m sure that my cognitive abilities would be at least a little impaired. It doesn’t sound like they included orthostatic intolerance as part of their study though.
Click to expand...
That would be interesting. Maybe someone knows of a study done about that.

I have difficulty sitting upright when I am in deep PEM, too, or even just on a normal bad day, after being on my feet for an hour or two.

I also have difficulty making executive decisions, even about something as simple as cleaning up the kitchen counter or clearing off the kitchen table.
 
I think I experience something similar to what Violeta is describing. A recent example was I spilled some milk on the counter, and I was standing there for an embarrassingly long time just confused about what to do about it (tea towel seemed wrong, paper towel also seemed wrong, what do I normally do in this situation again?) I eventually used a fresh cloth out of the drawer, knowing this was wrong but not knowing what to do. (The correct answer, which I've done a thousand times, is using the sponge out of the sink, but I guess those neurons were taking the day off.)

I had ADHD before ME/CFS so my executive function/memory/common sense might just be the first thing to go when things aren't going well in my brain.
 
I believe these measures are likely to provide a framework for comparison with profiles found in other conditions.

“Most research on P50 relates to schizophrenia and related psychotic disorders. Many studies, though not all, report a reduction in P50 suppression” – Wikipedia entry on P50.

So, this is not the case here.
 
ScoutB said:
I think I experience something similar to what Violeta is describing. A recent example was I spilled some milk on the counter, and I was standing there for an embarrassingly long time just confused about what to do about it (tea towel seemed wrong, paper towel also seemed wrong, what do I normally do in this situation again?) I eventually used a fresh cloth out of the drawer, knowing this was wrong but not knowing what to do. (The correct answer, which I've done a thousand times, is using the sponge out of the sink, but I guess those neurons were taking the day off.)

I had ADHD before ME/CFS so my executive function/memory/common sense might just be the first thing to go when things aren't going well in my brain.
Click to expand...
Yes, that describes it. A feeling of being overwhelmed by something that at other times would be such a simple problem to resolve.

I sometimes find myself walking back and forth the 5 feet of counter space trying to figure out what to do.
 
You must log in or register to reply here.
Back
Top Bottom