The Association Between Amygdala Subfield-Related Functional Connectivity and Stigma Reduction 12 Months After Social Contacts: A Functional Neuroimaging Study in a Subgroup of a Randomized Controlled Trial

Multi-voxel neuro-reinforcement changes resting-state functional connectivity: A pilot study

Background

Multi-voxel neuro-reinforcement has been shown to selectively reduce amygdala reactivity in response to feared stimuli, but the precise mechanisms supporting these effects are still unknown. The current pilot study seeks to identify potential intermediaries of change using functional brain connectivity at rest.

Methods

Individuals (N = 11) diagnosed with at least two animal subtype specific phobias took part in a double-blind multi-voxel neuro-reinforcement clinical trial targeting one of two phobic animals, with the untargeted animal as placebo control. Changes in whole-brain resting state functional connectivity from pre-treatment to post-treatment were measured using group ICA. These changes were tested to see if they predicted the previously observed decreases in amygdala reactivity in response to images of target phobic animals.

Results

A common functional connectivity network overlapping with the visual network was identified in resting state data pre-treatment and post-treatment. Significant increases in functional connectivity in this network from pre-treatment to post-treatment were found in higher level visual and cognitive processing regions of the brain. Increases in functional connectivity in these regions also significantly predicted decreases in task-based amygdala reactivity to targeted phobic animals following multi-voxel neuro-reinforcement. Specifically, greater increases of functional connectivity pre-treatment to post-treatment were associated with greater decreases of amygdala reactivity to target phobic stimuli pre-treatment to post-treatment.

Conclusions

These findings provide preliminary evidence that multi-voxel neuro-reinforcement can induce persisting functional connectivity changes in the brain. Moreover, these changes in functional connectivity were not limited to the direct area of neuro-reinforcement, suggesting neuro-reinforcement may change how the targeted region interacts with other brain regions. Identification of these brain regions represent a first step towards explaining the underlying mechanisms of change in previous multi-voxel neuro-reinforcement studies. Future research should seek to replicate these effects in a larger sample size to further assess their role in the effects observed from multi-voxel neuro-reinforcement.

Felt Stigma and Its Underlying Contributors in Epilepsy Patients

Objective

To explore the correlated clinical and psychological factors of stigmatization and investigate the relationship between stigma and white matter abnormalities in epilepsy patients.

Methods

Stigmatization was obtained by a three-item stigma scale in 256 epilepsy patients with genetic or unknown etiology. Personality and quality of life (QOL) were assessed by Eysenck Personality Questionnaire (EPQ) and QOL-31 questionnaire respectively. One hundred and fourteen of them were performed Hamilton Depression Scale-17 (HAMD) and scanned with diffusion tensor imaging in 3T MRI. Fractional anisotropy (FA) values of frontotemporal contact fibers were calculated.

Results

There were about 39.8% patients felt stigma, with the highest score (Score 3) in 8.2% (21/256). Stigma scores were significantly negatively correlated with education (P < 0.01), age of onset (P < 0.05), extraversion score of EPQ (P < 0.01), total and all the subscale QOL scores (P < 0.001), and positively correlated with duration (P < 0.01), HAMD score (P < 0.001), neuroticism score of EPQ (P < 0.001). We found negative correlation between stigma scores and FA values of right superior longitudinal fasciculus and left cingulum (P < 0.05). Logistic regression results showed that FA value of left cingulum (P = 0.011; OR = 0.000), social function (P = 0.000; OR = 0.935) of QOL, and neuroticism score of EPQ (P = 0.033; OR = 1.123) independently correlated to felt stigma.

Conclusion

Felt stigma in epilepsy patients was found to be correlated with neuroticism, depression, and deficient social function of QOL, which might be predisposed by the impairment of the left cingulum. Our results provide preliminary evidence for the underlying neural circuits in stigmatization.