Poster Session 04 Program Schedule
02/15/2024
12:00 pm - 01:15 pm
Room: Shubert Complex (Posters 1-60)
Poster Session 04: Neuroimaging | Neurostimulation/Neuromodulation | Teleneuropsychology/Technology
Final Abstract #37
Exploring the role of the dorsolateral prefrontal cortex in emotional regulation and executive function: a High-Definition Transcranial Direct Current Stimulation (HD-tDCS) study
Loredana Frau, Liverpool John Moores University, Liverpool, United Kingdom
Valentina Cazzato, Liverpool John Moores University, Liverpool, United Kingdom
Davide Bruno, Liverpool John Moores University, Liverpool, United Kingdom
Category: Neurostimulation/Neuromodulation
Keyword 1: neurostimulation
Keyword 2: emotional processes
Keyword 3: executive functions
Objective:
High-definition transcranial Direct Current Stimulation (HD-tDCS) is a non-invasive brain stimulation technique that delivers a low-intensity direct current to modulate the activity of specific brain regions. Although HD-tDCS has been primarily investigated for its effects on cognitive functions, particularly executive functions, there is limited evidence suggesting that it may have effects on heart rate variability (HRV). HRV is an index of parasympathetic activation and is associated with emotional regulation, stress response, and neural plasticity.
According to the Neurovisceral Integration model (NIM; Thayer, 2009), high parasympathetic activity mediated by the vagus nerve is associated with heightened activation in the prefrontal cortex. As such, influencing HRV with HD-tDCS over the prefrontal cortex can yield significant implications for executive functioning.
This study aimed to examine the effects of HD-tDCS on autonomic nervous system activity, as measured by HRV, during cognitive tasks related to prefrontal activity.
Participants and Methods:
N=19 young adults (Mean age = 27 years old, SD = 5.33) and N=17 older adults (Mean age = 68 years old, SD = 5.04) took part in a single-blind and cross-over study. HD-tDCS was applied for 20 minutes at 2mA to the left dorsolateral prefrontal cortex (DLPFC). In two separate visits, all participants received either anodal (active) or sham stimulation (placebo). N-Back and Stroop tasks were used to assess working memory and inhibitory control, respectively. Participants completed tasks at two points: before and during- HD-tDCS. Frequency-domain HRV was computed for high frequency (HF; 0.15-0.4Hz) power, reflecting parasympathetic activity.
Results:
The results revealed a significant improvement in accuracy for the N-Back task and a decrease in response time for the Stroop task in the anodal condition compared to the sham condition. Moreover, when compared to baseline, HF-HRV was significantly higher during anodal HD-tDCS, but not during sham HD-tDCS. Consistent with the NIN model, there was a positive correlation between changes in HF-HRV during anodal HD-tDCS and N-Back accuracy, as well as a negative association with Stroop task response time, compared to baseline levels and sham HD-tDCS.
Conclusions:
Overall, this study demonstrates that anodal HD-tDCS stimulation over the left DLPFC resulted in increased HRV levels and executive performance. These findings in particular suggest that HD-tDCS has the potential to modulate autonomic nervous system activity related to working memory and inhibitory control capacity. Consequently, HD-tDCS may represent a promising tool for managing cognitive deficits and emotional disorders, such as stress-related disorders, in both clinical and healthy populations.
However, further research is necessary to better understand the relationships between brain stimulation and autonomic processes across different cognitive tasks and diverse age groups.
| 
