Structural brain alterations and predictors of clinical improvement in functional cognitive disorder after concussion, 2025, Westlin, Perez+

[SNT Gatchaman]

Structural brain alterations and predictors of clinical improvement in functional cognitive disorder after concussion

Spoiler: Authors

Westlin; Rioux; Lee; Panenka; Palombo; Todd; Silverberg; Perez

Functional cognitive disorder (FCD) is an under-studied yet likely prevalent subtype of functional neurological disorder (FND), with neural mechanisms that remain poorly understood. While studies of other FND subtypes have revealed structural and functional brain alterations across several large-scale brain networks, no study to date has investigated neural alterations in FCD.

Here, we examined structural grey matter brain differences as measured from magnetic resonance imaging in 37 adults with FCD after concussion compared to 25 post-concussion controls. We compared FreeSurfer-based cortical thickness and subcortical volumes between groups and investigated associations between structural measures and memory symptoms. A subset of participants with FCD (n = 24) participated in a randomized controlled trial of cognitive-behavioral therapy vs. cognitive rehabilitation, and relationships between baseline structural measures and treatment outcomes were evaluated. All primary analyses were adjusted for age, sex, estimated IQ, and loss of consciousness, and corrected for multiple comparisons.

No significant between-group differences in cortical thickness or subcortical volume were observed. However, across all participants, greater functional memory symptom severity was associated with larger right amygdala volume, which remained significant adjusting for depression scores, anxiety scores, and psychotropic medication use. Post-hoc analyses identified that this observation was driven by differences in lateral, basal, and paralaminar amygdalar nuclei. Additionally, greater improvement in memory symptoms following treatment was associated with increased pre-treatment cortical thickness in the right inferior frontal gyrus.

These findings provide initial insights into the structural neurobiology of FCD and its associations with symptom severity and clinical trajectories.

HIGHLIGHTS
• Initial study of structural MRI alterations in functional cognitive disorder

• Functional memory symptom severity correlated with right amygdala volume.

• Clinical improvement related to baseline right inferior frontal gyrus thickness.

Web | DOI | NeuroImage: Clinical | Open Access

 

[Sean]

So the 'functional' part is...?

 

[Utsikt]

3.4. Exploratory predictors of treatment outcomes​

In participants with FCD who underwent treatment (either CBT or cognitive rehabilitation), there was a significant positive relationship between improvement in FMDI scores and greater right inferior frontal gyrus (IFG)/pars triangularis cortical thickness pre-treatment (pcorrected = 0.02, see Fig. 3). This finding held when adjusting post-hoc for PHQ-9 (pcorrected = 0.002) and GAD-7 (pcorrected = 0.047) scores, but did not hold when adjusting for pre-treatment psychotropic medication use. There were no significant associations with absolute change scores for the MMQ-S.

This is the trial they talked about.

Unblinded and only subjective outcomes about how bothersome your symptoms are and things like that.

 

[V.R.T.]

So the 'functional' part is...?

Just more 'what doesn't kill you makes you stronger' nonsense.

Everyone with post concussion issues just has a functional issue you see. Ignore any evidence to the contrary. Because if viruses or head injuries caused serious disabling chronic symptoms we'd have to change the way we live. And that would cost money...

 

[rvallee]

So the 'functional' part is...?

Something about the mind being so powerful it can cause structural brain alterations. I'm sure they can milk a few years of relevance out of that.

Functional cognitive disorder (FCD), a cognitive subtype of functional neurological disorder (FND), is characterized by distressing and potentially disabling cognitive symptoms that occur in the absence of macroscopic structural neuropathology (e.g., focal brain lesions)

Or I guess they'll go with "it's microscopic, not macroscopic"? Or whatever. Here they just assert that CBT can reverse that. Funny how associations and correlations magically become a directional causality whenever convenient.

An improvement of functional memory symptoms following treatment (either cognitive behavioral therapy or cognitive rehabilitation), as measured by lower absolute change scores on the Functional Memory Disorder Inventory (FMDI), was associated with relative increases in pre-treatment cortical thickness of a right inferior frontal gyrus (IFG) region (pcorrected = 0.02) in patients with functional cognitive disorder (FCD)

Surely it can't be that a slow process of recovery in those areas leads to symptoms improvement. No, that would not be biopsychosocial, and since biopsychosocial is good, then it is good, and therefore useful in all circumstances. Or whatever is convenient in the moment.

Because if viruses or head injuries caused serious disabling chronic symptoms we'd have to change the way we live. And that would cost money.

Oh, ignoring that costs even more money to everyone, it's just that no one sees the bill.