Structural Integrity of the Uncinate Fasciculus and Resting State Functional Connectivity of the Ventral Prefrontal Cortex in Late Life Depression

Objectives: To investigate changes in functional connectivity between the vermis and cerebral regions in the resting state among subjects with bipolar disorder (BD).Methods: Thirty participants with BD and 28 healthy controls (HC) underwent the resting state functional magnetic resonance imaging (fMRI). Resting-state functional connectivity (rsFC) of the anterior and posterior vermis was examined. For each participant, rsFC maps of the anterior and posterior vermis were computed and compared across the two groups.Results: rsFC between the whole vermis and ventral prefrontal cortex (VPFC) was significantly lower in the BD groups compared to the HC group, and rsFC between the anterior vermis and the middle cingulate cortex was likewise significantly decreased in the BD group.Limitations: 83.3% of the BD participants were taking medication at the time of the study. Our findings may in part be attributed to treatment differences because we did not examine the effects of medication on rsFC. Further, the mixed BD subtypes in our current study may have confounding effects influencing the results.Conclusions: These rsFC differences of vermis-VPFC between groups may contribute to the BD mood regulation.

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Altered resting-state functional connectivity in late-life depression: A cross-sectional study

Journal of Affective Disorders ◽

10.1016/j.jad.2015.09.011 ◽

2016 ◽

Vol 189 ◽

pp. 126-133 ◽

Cited By ~ 25

Author(s):

Harris A. Eyre ◽

Hongyu Yang ◽

Amber M. Leaver ◽

Kathleen Van Dyk ◽

Prabha Siddarth ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Late Life ◽

Cross Sectional Study ◽

Sectional Study ◽

Late Life Depression ◽

Resting State Functional Connectivity ◽

Cross Sectional

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Resting State Functional Connectivity and Outcomes of Psychotherapies for Late-life Depression

10.31234/osf.io/uncsz ◽

2020 ◽

Author(s):

Nili Solomonov ◽

Lindsay W. Victoria ◽

Katharine Dunlop ◽

Matteo Respino ◽

Matthew Hoptman ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Rating Scale ◽

Depression Scale ◽

Late Life ◽

Anterior Cingulate ◽

Middle Temporal Gyrus ◽

Late Life Depression ◽

Resting State Functional Connectivity ◽

Depressive Episodes

Background: Problem solving therapy (PST) and “Engage”, a reward-exposure” based therapy, are important treatment options for late-life depression, given modest efficacy of antidepressants in this disorder. Abnormal function of the reward and default mode networks has been observed during depressive episodes. This study examined whether resting state functional connectivity (rsFC) of reward and DMN circuitries is associated with treatment outcomes. Methods: Thirty-two older adults with major depression (mean age = 72.7) were randomized to 9-weeks of either PST or “Engage”. We assessed rsFC at baseline and Week 6. We placed seeds in three a priori regions of interest: subgenual cingulate (sgACC), dorsal anterior cingulate cortex (dACC), and nucleus accumbens (NAcc). Outcome measures included the Hamilton Depression Rating Scale (HAMD) and the Behavioral Activation for Depression Scale (BADS).Results: In both PST and “Engage”, higher rsFC between the sgACC and middle temporal gyrus at baseline was associated with greater improvement in depression severity (HAMD). Preliminary findings suggested that in “Engage” treated participants, lower rsFC between the dACC and DMPFC at baseline was associated with HAM-D improvement. Finally, in Engage only, increased rsFC from baseline to Week 6 between NAcc and Superior Parietal Cortex was associated with increased BADS scores.Conclusion: The results suggest that patients who present with higher rsFC between the sgACC and a structure within the DMN may benefit from behavioral psychotherapies for late life depression. ‘Engage’ may lead to increased rsFC within the reward system reflecting a reconditioning of the reward systems by reward exposure.

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Mechanisms of transcranial magnetic stimulation in the treatment of anorexia nervosa

BJPsych Open ◽

10.1192/bjo.2021.180 ◽

2021 ◽

Vol 7 (S1) ◽

pp. S49-S50

Author(s):

Lydia Shackshaft

Keyword(s):

Anorexia Nervosa ◽

Prefrontal Cortex ◽

Functional Connectivity ◽

Resting State ◽

High Frequency ◽

Magnetic Stimulation ◽

Dorsolateral Prefrontal Cortex ◽

Resting State Functional Connectivity ◽

Dorsolateral Prefrontal ◽

Neurophysiological Mechanisms

AimsSevere and Enduring Anorexia Nervosa (SE-AN) is a challenging condition to treat, with limited therapeutic options, high morbidity, and the highest mortality rates of any psychiatric illness. Repetitive Transcranial Magnetic Stimulation (rTMS) is an emerging treatment option, as evidence demonstrates promising efficacy in improving mood and reducing core Anorexia Nervosa symptoms, as well as safety and tolerability to patients. We aimed to investigate the neurophysiological mechanisms of rTMS use in SE-AN patients by assessing changes in resting state functional connectivity, in the first functional neuroimaging analysis investigating rTMS effects in Anorexia Nervosa patients.Method26 females with a current diagnosis of SE-AN received 20 sessions of sham or real high frequency rTMS (10 hertz) to the left dorsolateral prefrontal cortex in a randomised double-blind trial. Resting-state functional magnetic resonance imaging was performed before and after rTMS. Neural correlates of rTMS treatment were identified using a seed-based functional connectivity analysis with the left dorsolateral prefrontal cortex and bilateral amygdalae as regions of interest. Functional connectivity differences were analysed using t-contrasts in a mixed ANOVA (flexible factorial analysis) to assess interactions between treatment group (real rTMS vs sham) and time-point (pre or post TMS).ResultNo statistically significant changes in resting-state functional connectivity were observed post-rTMS compared to baseline in participants receiving active rTMS compared to sham. Increased functional connectivity between the left amygdala and left pre-supplementary motor area was observed to reach cluster-wise significance (PFWE < 0.05). However, after Bonferroni correction for multiple comparisons (3 seed regions), this did not reach the significance threshold PFWE <0.017.ConclusionThis study highlights the need for further investigation of neurophysiological mechanisms, including resting-state functional connectivity modulation, resulting from rTMS to the dorsolateral prefrontal cortex in SE-AN patients. This requires higher powered studies to account for heterogeneity in treatment response. We have provided some indication that high frequency rTMS may have therapeutic benefit in SE-AN by modification of functional connectivity between prefrontal and limbic brain regions, resulting in improved top-down cognitive control over emotional processing and ability to enact goal-directed behaviours, enabling secondary reductions in eating disorder behaviours.

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