Does non-invasive brain stimulation applied over the dorsolateral prefrontal cortex non-specifically influence mood and emotional processing in healthy individuals?

The ability to regulate the intake of unhealthy foods is critical in modern, calorie dense food environments. Frontal areas of the brain, such as the dorsolateral prefrontal cortex (DLPFC), are thought to play a central role in cognitive control and emotional regulation. Therefore, increasing activity in the DLPFC may enhance these functions which could improve the ability to reappraise and resist consuming highly palatable but unhealthy foods. One technique for modifying brain activity is transcranial direct current stimulation (tDCS), a non-invasive technique for modulating neuronal excitability that can influence performance on a range of cognitive tasks. We tested whether tDCS targeting the DLPFC would influence how people perceived highly palatable foods. In the present study, 98 participants were randomly assigned to receive a single session of active tDCS or sham stimulation. While receiving active or sham stimulation, participants viewed images of highly palatable foods and reported how pleasant it would be to eat each food (liking) and how strong their urge was to eat each food (wanting). We found that participants who received active versus sham tDCS stimulation perceived food as less pleasant, but there was no difference in how strong their urge was to eat the foods. Our findings suggest that modulating excitability in the DLPFC influences “liking” but not “wanting” of highly palatable foods. Non-invasive brain stimulation might be a useful technique for influencing the hedonic experience of eating and might have implications for changing food consumption.

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Locations for noninvasive brain stimulation in treating depressive disorders: A combination of meta-analysis and resting-state functional connectivity analysis

Australian & New Zealand Journal of Psychiatry ◽

10.1177/0004867420920372 ◽

2020 ◽

Vol 54 (6) ◽

pp. 582-590 ◽

Cited By ~ 3

Author(s):

Binlong Zhang ◽

Jiao Liu ◽

Tuya Bao ◽

Georgia Wilson ◽

Joel Park ◽

...

Keyword(s):

Prefrontal Cortex ◽

Functional Connectivity ◽

Brain Stimulation ◽

Dorsolateral Prefrontal Cortex ◽

Depressive Disorders ◽

Meta Analysis ◽

Resting State Functional Connectivity ◽

Noninvasive Brain Stimulation ◽

Brain Surface ◽

Dorsolateral Prefrontal

Objective: Many noninvasive brain stimulation techniques have been applied to treat depressive disorders. However, the target brain region in most noninvasive brain stimulation studies is the dorsolateral prefrontal cortex. Exploring new stimulation locations may improve the efficacy of noninvasive brain stimulation for depressive disorders. We aimed to explore potential noninvasive brain stimulation locations for depressive disorders through a meta-analysis and a functional connectivity approach. Methods: We conducted a meta-analysis of 395 functional magnetic resonance imaging studies to identify depressive disorder–associated brain regions as regions of interest. Then, we ran resting-state functional connectivity analysis with three different pipelines in 40 depression patients to find brain surface regions correlated with these regions of interest. The 10–20 system coordinates corresponding to these brain surface regions were considered as potential locations for noninvasive brain stimulation. Results: The 10–20 system coordinates corresponding to the bilateral dorsolateral prefrontal cortex, bilateral inferior frontal gyrus, medial prefrontal cortex, supplementary motor area, bilateral supramarginal gyrus, bilateral primary motor cortex, bilateral operculum, left angular gyrus and right middle temporal gyrus were identified as potential locations for noninvasive brain stimulation in depressive disorders. The coordinates were: posterior to F3, posterior to F4, superior to F3, posterior to F7, anterior to C4, P3, midpoint of F7–T3, posterior to F8, anterior to C3, midpoint of Fz–Cz, midpoint of Fz–Fp1, anterior to T4, midpoint of C3–P3, and anterior to C4. Conclusion: Our study identified several potential noninvasive brain stimulation locations for depressive disorders, which may serve as a basis for future clinical investigations.

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Transcranial direct current stimulation (tDCS) over vmPFC modulates interactions between reward and emotion in delay discounting

Scientific Reports ◽

10.1038/s41598-019-55157-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Aurélie L. Manuel ◽

Nicholas W. G. Murray ◽

Olivier Piguet

Keyword(s):

Prefrontal Cortex ◽

Delay Discounting ◽

Dorsolateral Prefrontal Cortex ◽

Positive Emotions ◽

Healthy Individuals ◽

Trade Offs ◽

Cathodal Tdcs ◽

Dorsolateral Prefrontal ◽

Stimulation Of

AbstractDelay discounting requires computing trade-offs between immediate-small rewards and later-larger rewards. Negative and positive emotions shift decisions towards more or less impulsive responses, respectively. Models have conceptualized this trade-off by describing an interplay between “emotional” and “rational” processes, with the former involved during immediate choices and relying on the ventromedial prefrontal cortex (vmPFC), and the latter involved in long-term choices and relying on the dorsolateral prefrontal cortex (dlPFC). Whether stimulation of the vmPFC modulates emotion-induced delay discounting remains unclear. We applied tDCS over the vmPFC in 20 healthy individuals during a delay discounting task following an emotional (positive, negative) or neutral induction. Our results showed that cathodal tDCS increased impulsivity after positive emotions in high impulsivity trials. For low impulsivity trials, anodal tDCS decreased impulsivity following neutral induction compared with emotional induction. Our findings demonstrate that the vmPFC integrates reward and emotion most prominently in situations of increased impulsivity, whereas when higher cognitive control is required the vmPFC appears to be less engaged, possibly due to recruitment of the dlPFC. Understanding how stimulation and emotion influence decision-making at the behavioural and neural levels holds promise to develop interventions to reduce impulsivity.

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