Neural processes linking joint hypermobility and anxiety: key roles for the amygdala and insular cortex 2025 Harrison, Eccles et al

[Andy]

Abstract

Background
Anxiety symptoms are elevated among people with joint hypermobility. The underlying neural mechanisms are attributed theoretically to effects of variant connective tissue on the precision of interoceptive representations contributing to emotions.

Aim
To investigate the neural correlates of anxiety and hypermobility using functional neuroimaging.

Method
We used functional magnetic resonance neuroimaging to quantify regional brain responses to emotional stimuli (facial expressions) in people with generalised anxiety disorder (GAD) (N = 30) and a non-anxious comparison group (N = 33). All participants were assessed for joint laxity and were classified (using Brighton Criteria) for the presence and absence of hypermobility syndrome (HMS: now considered hypermobility spectrum disorder).

Results
Participants with HMS showed attenuated neural reactivity to emotional faces in specific frontal (inferior frontal gyrus, pre-supplementary motor area), midline (anterior mid and posterior cingulate cortices) and parietal (precuneus and supramarginal gyrus) regions. Notably, interaction between HMS and anxiety was expressed in reactivity of the left amygdala (a region implicated in threat processing) and mid insula (primary interoceptive cortex) where activity was amplified in people with HMS with GAD. Severity of hypermobility in anxious, compared with non-anxious, individuals correlated with activity within the anterior insula (implicated as the neural substrate linking anxious feelings to physiological state). Amygdala-precuneus functional connectivity was stronger in participants with HMS, compared with non-HMS participants.

Conclusions
The predisposition to anxiety in people with variant connective tissue reflects dynamic interactions between neural centres processing threat (amygdala) and representing bodily state (insular and parietal cortices). Correspondingly, interventions to regulate amygdala reactivity while enhancing interoceptive precision may have therapeutic benefit for symptomatic hypermobile individuals.

Open access

 

[Hutan]

Anxiety symptoms are elevated among people with joint hypermobility. The underlying neural mechanisms are attributed theoretically to effects of variant connective tissue on the precision of interoceptive representations contributing to emotions.

That's pretty clear, isn't. These researchers are approaching the study with a clear preconception that 'those hypermobile people are an anxious lot'.

So, they recruited 30 people with Generalised Anxiety Disorder and 33 people without.

Sixty-three participants were recruited to the study. People volunteered to participate in response to an advertisement from Sussex Partnership NHS Trust either after inclusion in a linked study or via electronic bulletin boards. Members of the non-clinical comparison group were recruited via electronic bulletin boards. Of the 63 participants, 30 (47.6%) participants (age; mean ± s.e.m.) = 42.93 ± 2.24 yrs, 18 female, 12 male) met the threshold for generalised anxiety disorder (GAD), and 33 (52.4%) participants (age; mean ± s.e.m. = 37.42 ± 2.28 yrs, 16 female, 17 male) were healthy controls.

There were no statistically significant differences in age or gender between the two groups. Of the people with GAD, 18 (60%) were classified as having joint hypermobility syndrome, and 7 (21.2%) of the non-clinical comparison group met the diagnostic threshold for joint hypermobility syndrome. See Table 1 for participant demographic details and clinical features.

Table 1

Notice that they don't report the BAI (Beck Anxiety Inventory) score for the subsets of people with hypermobility and without hypermobility in the anxiety and healthy control groups. There's probably a reason for that - within each group, anxiety didn't differ between the hypermobile and non-hypermobile subgroups.

There was no significant difference in anxiety levels between those with HMS and those without, either in the anxious (mean ± s.e.m.: anxious group: HMS 23.28 ± 2.37 versus anxious group: non-HMS 22.42 ± 2.82; t(28) = −0.23, P = 0.818) or non-anxious group (non-anxious group: HMS 5.38 ± 0.74 versus non-anxious group: non-HMS 5.86 ± 1.92; t(31) = −0.27, P = 0.786).

Clearly not everyone with anxiety is hypermobile; not everyone who is hypermobile has anxiety.

 

[Jonathan Edwards]

I find it hard to follow but it seems the HMS people responded less to emotive faces except "notably" (cos it fits the theory) anxious HMS people responded more in one tiny bit of brain.

The whole thing seems to be an entry for the Ignobel Prize 2025.

 

[Hutan]

Notice also that Table 1 doesn't report the number of people in each subset by sex. We don't know if there are more women in the hypermobility groups than in the non-hypermobility groups. Probably there are.

But we do know that the sex ratios in the anxiety and the non-anxiety groups are not matched. And also that by the time they are slicing and dicing all the groups, the sample sizes are pretty small.

 

[Eleanor]

When I am queen of the universe, this kind of cherry-picking and suppression of results to fit preconceived ideas will result in the researcher(s) concerned being automatically disqualified from receiving any funding ever again. And possibly their institutions too. Tough love, it's the only way.

 

[Jonathan Edwards]

When I am queen of the universe, this kind of cherry-picking and suppression of results to fit preconceived ideas will result in the researcher(s) concerned being automatically disqualified from receiving any funding ever again. And possibly their institutions too. Tough love, it's the only way.

Why not be the red queen of the universe?

Off with their heads!

 

[Utsikt]

Off with their heads!

BREAKING NEWS!!
Prominent chronic fatigue anti-recovery activist wants to behead scientists that disagrees with him.

I expect a Pulitzer and police protection for my work here. Or at least some funding to research how online activity influences chronic fatigue patients’ willingness to behead scientists.