Prediction bias for physical exertion in chronic fatigue: Evidence from an observational paradigm 2026 Kubis et al

[Andy]

Highlights​

• A new paradigm reveals central prediction bias for exertion in observed exercise tasks.
• Participants with chronic fatigue predicting higher exertion levels than controls during exercise observations.
• RPE bias in chronic fatigue links to fatigue and disability scores but not to characteristics of observed individuals.
• Control group RPE bias is tied to the observed individuals’ characteristics and not to the observer characteristics.
• Chronic fatigue relates to higher prediction bias for exertion for observed exercise tasks.

Abstract​

Many clinical conditions are associated with a high incidence of chronic fatigue. While some physiological causes for chronic fatigue are established, e.g., processes connected to inflammation, psychological factors may also contribute. The metacognitive theory of dyshomeostasis proposes that a mismatch between cognitive predictions and sensory evidence for actions undermines self-efficacy and perception of control, contributing to chronic fatigue.

We aimed to investigate alterations in prediction for physical exertion in participants with chronic fatigue using a new paradigm based on observation, therefore avoiding sensory feedback from the periphery. Participants watched randomised sets of videos with people exercising at different physical exertion levels. Participants had to predict the rate of physical exertion (RPE) of the individuals observed in the videos. Additionally, questionnaires for chronic fatigue, disability, mood, clinical history and body characteristics were assessed. 49 complete data sets from participants with chronic fatigue and 74 data sets from control subjects were analysed in this study.

Compared with the control group, participants with chronic fatigue predicted a significantly higher RPE for the observed exercising individuals across all exertion levels. Multiple linear regression models revealed that in the control group, the variance of the bias in the prediction of exertion was significantly explained by the characteristics of the individuals observed in the videos. However, in the chronic fatigue group, the variance of bias in the prediction of exertion was strongly explained by the characteristics of the observer, i.e. fatigue levels and disability. Outcomes revealed that participants with chronic fatigue predicted higher exertion levels during observations and that levels were strongly influenced by their clinical symptoms, suggesting a prediction bias for exertion being present even without performing physical tasks.

Open access

 

[Utsikt]

How is it possible to always interpret the data in the least plausible manner?

Of course people with chronic fatigue will think that physical exertion requires more effort than people without chronic fatigue - because that is what they experience themselves.

And if someone expects a task to be more strenuous than it actually is, that will create a positive surprise and should lower the fatigue they experience - if fatigue is a result of a deviation between the prediction and the reality. Fatigue should only kick in if the task is more strenuous than they expected.

The authors don’t even understand what their own model would predict, no pun intended.

 

[rvallee]

Compared with the control group, participants with chronic fatigue predicted a significantly higher RPE for the observed exercising individuals across all exertion levels.

Obviously, and perfectly expected if you know anything about it. This is why you don't judge a model based on what the model says. Every model is consistent with itself. What the hell is this high school level garbage study and why aren't there adults who stop this nonsense?

 

[bobbler]

Highlights​

• A new paradigm reveals central prediction bias for exertion in observed exercise tasks.
• Participants with chronic fatigue predicting higher exertion levels than controls during exercise observations.
• RPE bias in chronic fatigue links to fatigue and disability scores but not to characteristics of observed individuals.
• Control group RPE bias is tied to the observed individuals’ characteristics and not to the observer characteristics.
• Chronic fatigue relates to higher prediction bias for exertion for observed exercise tasks.

Abstract​

Many clinical conditions are associated with a high incidence of chronic fatigue. While some physiological causes for chronic fatigue are established, e.g., processes connected to inflammation, psychological factors may also contribute. The metacognitive theory of dyshomeostasis proposes that a mismatch between cognitive predictions and sensory evidence for actions undermines self-efficacy and perception of control, contributing to chronic fatigue.

We aimed to investigate alterations in prediction for physical exertion in participants with chronic fatigue using a new paradigm based on observation, therefore avoiding sensory feedback from the periphery. Participants watched randomised sets of videos with people exercising at different physical exertion levels. Participants had to predict the rate of physical exertion (RPE) of the individuals observed in the videos. Additionally, questionnaires for chronic fatigue, disability, mood, clinical history and body characteristics were assessed. 49 complete data sets from participants with chronic fatigue and 74 data sets from control subjects were analysed in this study.

Compared with the control group, participants with chronic fatigue predicted a significantly higher RPE for the observed exercising individuals across all exertion levels. Multiple linear regression models revealed that in the control group, the variance of the bias in the prediction of exertion was significantly explained by the characteristics of the individuals observed in the videos. However, in the chronic fatigue group, the variance of bias in the prediction of exertion was strongly explained by the characteristics of the observer, i.e. fatigue levels and disability. Outcomes revealed that participants with chronic fatigue predicted higher exertion levels during observations and that levels were strongly influenced by their clinical symptoms, suggesting a prediction bias for exertion being present even without performing physical tasks.

Open access

The irony

The issue for people with ‘whatever’ (noting also that this is about chronic fatigue whatever that is by their definition where the issue is the opposite to what these people assume with me/cfs as we do ‘the thing’ at the time potentially’ok’ vs the then not waking up 36hrs later or being able to move ) in what these people are actually testing in their ‘experiment’ is apparently ‘bias’ based on their own experience or body.

This is all about this author selling a manifesto suggesting that they are not disabled because they ‘don’t think disabled’ where those with chronic fatigue specifically they are selling bigoted but either more words to try and hide it ‘just expect it so think they feel more tired than they are’

Which is chalders/moss Morris bigoted throw made up nasty misogynistic personality slights that happen to be tropes about hysterical women at the disabled nonsense reworded.

But they can’t see that their own bias is as blinking obvious here. These are videos and what they’ve decided they can see as ‘attributes’ of the individuals in a video is as honed as someone who is actually ill and being bullied due to this type of incitement of society ? Or is it that they’ve asked each individual to write down what they see and then how have they worked that in ?

All that has happened is that unsurprisingly disabled people and ill people are more educated smart and intelligent to things those who’ve no experience or proper interest (that isn’t biased to being an antagonist to them but empathic interest and scientific curiosity) can see things that those who’ve no experience and don’t have to deal with the consequences but instead blindly cause them because they are ignorant in the literal sense of he word ‘don’t see’ and then called the more experienced ones wrong because it is different and ‘the controls must be right’

It’s lunacy

 

[bobbler]

How is it possible to always interpret the data in the least plausible manner?

Of course people with chronic fatigue will think that physical exertion requires more effort than people without chronic fatigue - because that is what they experience themselves.

And if someone expects a task to be more strenuous than it actually is, that will create a positive surprise and should lower the fatigue they experience - if fatigue is a result of a deviation between the prediction and the reality. Fatigue should only kick in if the task is more strenuous than they expected.

The authors don’t even understand what their own model would predict, no pun intended.

It’s an interesting one because an actual equivalent they need to use to calibrate even normal people’s reactions to actual things is for those who aren’t athletes to watch things like a full marathon, worlds strongest man lifting of something obviously extremely heavy etc

I’d suspect most would relate better to the latter in accuracy simply because of the size of the person and the size of the stone being lifted but also that it tends to show on their faces and bodies

Whereas if no one has run a 200m anywhere near 20s they have no clue what it requires from a body and whilst they might think marathon is a long way because ‘they only ever ran 5km and that was far’ it doesn’t get close to being in that person who is doing it in a world record times’ body.

So the whole thing is obscure and arrogant that the PIs thought they knew what ‘the correct’ factors were in the video and termed anything else wrong when it’s just as likely the other way around - I don’t even know if they knew the people in the video and those participants wanted to go into deep detail about their intimate niggles or mightnt even been aware of them or not been told the full context when asked that would have changed everything about what I’d have answered.