Search Results (29)

Objectives: Habitual exercise has been associated with a lower risk of emotional disorders and greater emotional stability. However, it remains unclear whether the beneficial effects of habitual aerobic exercise primarily emerge during the stage of emotion elicitation or during the subsequent regulation of negative emotions. The present study examined the association of habitual aerobic exercise with the intensity of negative emotion elicitation, the effectiveness of emotion regulation strategies, and patterns of prefrontal activation measured using functional near-infrared spectroscopy. Methods: Sixty-four participants were recruited, including individuals with habitual aerobic exercise (trained group, n = 32) and those without regular exercise habits (untrained group, n = 32). Participants completed an emotion regulation task consisting of four conditions: viewing neutral images, viewing negative images, cognitive reappraisal, and expressive suppression. The comparison between neutral and negative viewing conditions was used to assess emotional elicitation, whereas comparisons between the regulation conditions and passive viewing of negative images were used to assess emotion regulation effects. Results: Compared with the untrained group, the trained group showed a lower emotional elicitation effect, accompanied by lower right ventrolateral prefrontal cortex (rVLPFC) activation during picture viewing at a more liberal threshold. The two groups showed similar reductions in negative emotional experience during emotion regulation, whereas individuals with habitual exercise showed a trend toward lower right dorsolateral prefrontal cortex (rDLPFC) activation during expressive suppression. Conclusions: Habitual aerobic exercise is associated with greater emotional stability, characterized by reduced initial emotional reactivity during emotion elicitation. Habitual exercisers may also show more efficient neural processing, reflected in distinct prefrontal activation patterns during emotional processing and regulation, although these exploratory findings require confirmation in future research. Full article

Background and Objectives: Parkinson’s disease (PD) is a neurodegenerative disorder marked by bradykinesia, rigidity, and tremor. While deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) effectively alleviates motor symptoms, the potential of targeting the substantia nigra pars reticulata (SNr) is less understood. This study investigates the effects of mid-term DBS of the SNr on motor function and neuroplasticity in a 6-hydroxydopamine (6-OHDA) rat model of PD. Methods: Adult male Sprague-Dawley rats (280–300 g) were divided into healthy control (n = 10), PD (n = 9), sham-DBS (n = 7), and SNr-DBS (n = 7) groups. Bilateral striatal 6-OHDA lesions induced PD. High-frequency (130 Hz, 60 µs) SNr-DBS was delivered for 14 days. Locomotor activity (open-field), gait (footprint method), and motor coordination (rotarod) were assessed. Tyrosine hydroxylase (TH) expression in the SN and c-Fos and BDNF expression in the cerebellum, prefrontal cortex (PFC), and ventrolateral thalamus were analyzed histologically. Results: SNr-DBS significantly improved ambulation and horizontal activity compared to the PD group (p < 0.05). Gait analysis showed significant improvements in forelimb/hindlimb stride length and stance width, while rotarod performance indicated enhanced motor coordination (p < 0.05). Histology revealed increased TH expression in the SN and elevated c-Fos and BDNF levels in the cerebellum, PFC, and thalamus in the SNr-DBS group vs. PD rats (p < 0.05). Conclusions: Mid-term SNr-DBS produced significant functional gains in motor activity and coordination in a 6-OHDA PD model, together with molecular evidence of dopaminergic enhancement and neuroplastic activation. These translational findings suggest that targeting the SNr may offer a clinically relevant alternative for patients with PD, particularly for those who may not optimally respond to conventional STN or GPi stimulation. Full article

Emotional attunement, or emotional co-regulation in a relationship, can manifest as interpersonal neural synchrony, where partners exhibit similar anti-phase or phase-shifted brain activity. In adult romantic relationships, emotional attunement may differ according to relationship satisfaction. No study has examined how relationship satisfaction difference influences interpersonal neural synchrony. This exploratory pilot study on 17 couples (unmarried Chinese undergraduate couples in a Southeast Asian university) investigated whether relationship satisfaction difference influenced interpersonal neural synchrony during a shared emotive experience. Each couple wore an fNIRS cap to measure brain activity in their prefrontal cortex (PFC) while co-viewing seven videos intended to evoke positive, negative or neutral emotions. We found preliminary evidence that relationship satisfaction difference modulated interpersonal neural synchrony in the right ventral PFC regions, including the right ventromedial PFC (involved in the encoding of emotional values to stimuli and emotional regulation), right ventrolateral PFC (involved in voluntary emotional regulation) and the right orbitofrontal cortex (involved in processing of emotional experiences and regulation of emotions). This suggested that couples with mismatched relationship satisfaction displayed greater interpersonal neural synchrony, possibly due to mutual social cognitive processes when viewing emotive videos together. Further studies can replicate the findings with larger, diverse samples. Full article

Background: Borderline Personality Disorder (BPD) is a severe psychiatric condition characterized by pervasive emotional dysregulation, impulsivity, and unstable interpersonal relationships. Affecting over 1% of the general population, BPD carries significant morbidity, frequent hospitalizations, and an increased risk of suicide. Although specialized psychotherapeutic approaches have shown efficacy, their impact is often constrained by availability, lengthy treatment durations, moderate effect sizes, and high dropout rates. Pharmacological treatments for BPD remain inadequate and are usually accompanied by adverse side effects. Objective: This narrative review seeks to explore the potential of transcranial direct current stimulation (tDCS) as a safe, cost-effective, and accessible neuromodulation intervention aimed at alleviating core BPD symptoms—namely, emotional dysregulation and impulsivity—while also addressing common comorbidities and opportunities for integration with existing therapeutic modalities. Methods: We conducted a narrative literature synthesis in accordance with the SANRA (Scale for the Assessment of Narrative Review Articles) guidelines. A PubMed/MEDLINE search was performed using keywords related to transcranial direct current stimulation (tDCS) and BPD, identifying five published randomized controlled trials on the topic. To provide a broader perspective, we also included studies from related fields examining mechanisms of action, safety and tolerability, cost-effectiveness, stimulation parameters, and clinical outcomes relevant to BPD. Results: Conventional tDCS protocols—typically involving 1–2 mA currents for 20–30 min—have demonstrated an excellent safety profile, resulting in only minimal and transient side effects without any risk of overdose or misuse, which is a key advantage for populations at high risk of suicidality. With moderately priced devices and the feasibility of home-based administration, tDCS provides a substantially more affordable alternative to both long-term pharmacotherapy and intensive psychotherapy. Neurobiologically, tDCS modulates the excitability of the dorsolateral and ventrolateral prefrontal cortex and enhances fronto-limbic connectivity, thereby strengthening top-down regulatory control over emotion and behavior. Pilot randomized controlled trials report moderate effect sizes for improvements in emotional regulation, inhibitory control, and rejection sensitivity, along with ancillary gains in executive functioning and reductions in depressive and substance-use symptoms when stimulating the left dorsolateral prefrontal cortex. Conclusions: tDCS stimulation emerges as a safe and scalable adjunctive treatment for BPD, leveraging targeted neuromodulation to address core features and common comorbidities like depression. However, variability in current protocols and the scarcity of well-powered randomized trials underscore the pressing need for standardized methodologies, longer-term follow-up, and individualized stimulation strategies to establish enduring clinical benefits. Full article

Background: Borderline Personality Disorder (BPD) is a debilitating mental health condition characterized by emotional dysregulation and interpersonal dysfunction, with perceived social rejection exacerbating these issues. Emerging evidence suggests that a single session of transcranial direct current stimulation (tDCS) over the right ventrolateral prefrontal cortex (rVLPFC) may decrease the unique tendency of BPD patients to feel rejected even when socially included during a laboratory task. Objectives: This protocol outlines a double-blind, sham-controlled study evaluating the longitudinal effects of repeated anodal tDCS over the right ventrolateral prefrontal cortex (rVLPFC) on rejection-related emotions (RRE) during real-life social interactions in individuals with BPD. Methods: Sixty BPD patients will be randomized to receive real or sham tDCS across 10 daily sessions, coupled with an ecological momentary assessment (EMA) protocol capturing emotional and behavioral responses to real-life social interactions over four timepoints: baseline, during treatment, ten days post-treatment, and three months post-treatment. Primary outcomes include changes in RRE, with exploratory analyses examining feelings of social connection, aggressive tendencies, trust toward others, and interpersonal and affective dynamics. Multilevel modeling will assess temporal and group-level effects. Expected Results and Impact: This study aims to establish the efficacy of tDCS in reducing BPD patients’ negative emotional response in real-life social situations and to determine whether such effects are maintained in time. The findings could advance the clinical application of tDCS as an adjunctive intervention to alleviate social–emotional impairments in BPD, addressing gaps in current treatment approaches and guiding future research into the neural mechanisms of social emotion regulation. Full article

Negative emotions can shape human visual perception, which is mainly investigated using basic emotions such as fear. Whether guilt emotion, which is a negative moral emotion originating late in our evolutionary ancestry, has similar modulatory effects as basic emotions is largely unexplored. Here, we employed a dot estimation task to induce feelings of guilt and subsequently measured the Ebbinghaus illusion strength. The photos of victims’ faces were projected on the central circle of the Ebbinghaus configuration. The results showed that guilt significantly strengthened the illusion effect relative to control condition, which was observed only for female participants playing with same-gender partners and reversed to the opposite pattern with disruption of left ventrolateral prefrontal cortex. The findings suggest that guilt can sculpt early visual perception in a gender-specific and prefrontal-dependent manner, thus broaden our understanding of guilt emotion and have implications for relevant neuropsychiatric disorders. Full article

Background: Problematic social media (SM) use is a growing concern, particularly among adolescents who are drawn to these platforms for social interactions important to their age group. SM dependence is characterized by excessive, uncontrolled usage that impairs personal, social, and professional aspects. Despite the ongoing debate over recognizing SM addiction as a distinct diagnostic category, the impact of social feedback, particularly through the “like” button, on brain activity remains under scrutiny. Objective: This systematic review aims to study the neural correlates of online social feedback, focusing on the effects of the “like” feedback on brain activity using fMRI and EEG. Methods: The review followed the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA). Results: The review included 11 studies with 504 participants, identifying key brain structures such as the amygdala, ventromedial prefrontal cortex (vmPFC), and ventral striatum involved in reward processing. Positive feedback (“likes”) activates areas like the nucleus accumbens (NACC), vmPFC, and amygdala, with NACC correlating with increased SM use intensity. Negative feedback activates the ventrolateral prefrontal cortex (vlPFC) and left medial prefrontal cortex (mPFC). Behavioral data indicates that positive feedback influences subsequent social interactions. Conclusions: The review highlights disparities in the literature regarding the neural response to social feedback, emphasizing the need for further research to clarify the roles of sex, personality traits, and the person giving feedback. Overall, understanding the neurobiological underpinnings of SM engagement is essential for developing effective interventions to prevent or address the negative effects of excessive SM use. Full article

Background: Humans exhibit a remarkable ability to synchronize their actions with external auditory stimuli through a process called auditory–motor or rhythmic entrainment. Positive effects of rhythmic entrainment have been demonstrated in adults with neurological movement disorders, yet the neural substrates supporting the transformation of auditory input into timed rhythmic motor outputs are not fully understood. We aimed to systematically map and synthesize the research on the neural correlates of auditory–motor entrainment and synchronization. Methods: Following the PRISMA-ScR guidelines for scoping reviews, a systematic search was conducted across four databases (MEDLINE, Embase, PsycInfo, and Scopus) for articles published between 2013 and 2023. Results: From an initial return of 1430 records, 22 studies met the inclusion criteria and were synthesized based on the neuroimaging modality. There is converging evidence that auditory–motor synchronization engages bilateral cortical and subcortical networks, including the supplementary motor area, premotor cortex, ventrolateral prefrontal cortex, basal ganglia, and cerebellum. Specifically, the supplementary motor area and the basal ganglia are essential for beat-based timing and internally guided rhythmic movements, while the cerebellum plays an important role in tracking and processing complex rhythmic patterns and synchronizing to the external beat. Self-paced tapping is associated with additional activations in the prefrontal cortex and the basal ganglia, suggesting that tapping in the absence of auditory cues requires more neural resources. Lastly, existing studies indicate that movement rate and the type of music further modulate the EEG power in the alpha and beta frequency bands. Conclusions: These findings are discussed in the context of clinical implications and rhythm-based therapies. Full article

Transcranial direct current stimulation (tDCS) is acknowledged for its non-invasive modulation of neuronal activity in psychiatric disorders. However, its application in insomnia research yields varied outcomes depending on different tDCS types and patient conditions. Our primary objective is to elucidate its efficiency and uncover the underlying mechanisms in insomnia treatment. We hypothesized that anodal prefrontal cortex stimulation activates glutamatergic projections from the infralimbic cortex (IL) to the ventrolateral preoptic area (VLPO) to promote sleep. After administering 0.06 mA of electrical currents for 8 min, our results indicate significant non-rapid eye movement (NREM) enhancement in naïve mice within the initial 3 h post-stimulation, persisting up to 16–24 h. In the insomnia group, tDCS enhanced NREM sleep bout numbers during acute stress response and improved NREM and REM sleep duration in subsequent acute insomnia. Sleep quality, assessed through NREM delta powers, remains unaffected. Interference of the IL-VLPO pathway, utilizing designer receptors exclusively activated by designer drugs (DREADDs) with the cre-DIO system, partially blocked tDCS’s sleep improvement in stress-induced insomnia. This study elucidated that the activation of the IL-VLPO pathway mediates tDCS’s effect on stress-induced insomnia. These findings support the understanding of tDCS effects on sleep disturbances, providing valuable insights for future research and clinical applications in sleep therapy. Full article

Due to the current limitations of three-dimensional (3D) simulation graphics technology, mind wandering commonly occurs in virtual reality tasks, which has impeded it being applied more extensively. The right ventrolateral prefrontal cortex (rVLPFC) plays a vital role in executing continuous two-dimensional (2D) mental paradigms, and transcranial direct current stimulation (tDCS) over this cortical region has been shown to successfully modulate sustained 2D attention. Accordingly, we further explored the effects of electrical activation of the rVLPFC on 3D attentional tasks using anodal high-definition (HD)-tDCS. A 3D Go/No-go (GNG) task was developed to compare the after effects of real and sham brain stimulation. Specifically, GNG tasks were periodically interrupted to assess the subjective perception of attentional level, behavioral reactions were tracked and decomposed into an underlying decision cognition process, and electroencephalography data were recorded to calculate event-related potentials (ERPs) in rVLPFC. The p-values statistically indicated that HD-tDCS improved the subjective mentality, led to more cautious decisions, and enhanced neuronal discharging in rVLPFC. Additionally, the neurophysiological P300 ERP component and stimulation being active or sham could effectively predict several objective outcomes. These findings indicate that the comprehensive approach including brain stimulation, 3D mental paradigm, and cross-examined performance could significantly lengthen and robustly compare sustained 3D attention. Full article

Overactive bladder (OAB) is a global problem reducing the quality of life of patients and increasing the costs of any healthcare system. The etiology of OAB is understudied but likely involves supraspinal network alterations. Here, we characterized supraspinal resting-state functional connectivity in 12 OAB patients and 12 healthy controls (HC) who were younger than 60 years. Independent component analysis showed that OAB patients had a weaker presence of the salience (Cohen’s d = 0.9) and default mode network (Cohen’s d = 1.1) and weaker directed connectivity between the fronto-parietal network and salience network with a longer lag time compared to HC. A region of interest analysis demonstrated weaker connectivity in OAB compared to HC (Cohen’s d > 1.6 or < −1.6), particularly within the frontal and prefrontal cortices. In addition, weaker seed (insula, ventrolateral prefrontal cortex) to voxel (anterior cingulate cortex, frontal gyrus, superior parietal lobe, cerebellum) connectivity was found in OAB compared to HC (Cohen’s d > 1.9). The degree of deviation in supraspinal connectivity in OAB patients (relative to HC) appears to be an indicator of the severity of the lower urinary tract symptoms and an indication that such symptoms are directly related to functional supraspinal alterations. Thus, future OAB therapy options should also consider supraspinal targets, while neuroimaging techniques should be given more consideration in the quest for better phenotyping of OAB. Full article

(1) Cognitive impairments such as working memory (WM) deficits are amongst the most common dysfunctions characterizing bipolar disorder (BD) patients, severely contributing to functional impairment. We aimed to investigate WM performance and associated brain activation during the acute phase of BD and to observe changes in the same patients during remission. (2) Frontal brain activation was recorded using functional near-infrared spectroscopy (fNIRS) during n-back task conditions (one-back, two-back and three-back) in BD patients in their acute depressive (n = 32) and remitted (n = 15) phases as well as in healthy controls (n = 30). (3) Comparison of BD patients during their acute phase with controls showed a trend (p = 0.08) towards lower dorsolateral prefrontal cortex (dlPFC) activation. In the remitted phase, BD patients showed lower dlPFC and ventrolateral prefrontal cortex (vlPFC) activation (p = 0.02) compared to controls. No difference in dlPFC and vlPFC activation between BD patients’ phases was found. (4) Our results showed decreased working memory performance in BD patients during the working memory task in the acute phase of disease. Working memory performance improved in the remitted phase of the disease but was still particularly attenuated for the more demanding conditions. Full article

Antisocial behavior involves actions that disregard the basic rights of others and may represent a threat to the social system. The neural processes associated with being subject to antisocial behavior, including social victimization, are still unknown. In this study, we used a social interaction task during functional magnetic resonance imaging to investigate the neural bases of social victimization. Brain activation and functional connectivity (FC) were estimated and correlated with the Big 5 Questionnaire, Temperament Evaluation in Memphis, Pisa and San Diego (TEMPS-M), and a Questionnaire of Daily Frustration scores. During social victimization, the right occipital and temporal cortex showed increased activation. The temporal cortex also had reduced FC with homotopic areas. Compared to the prosocial interaction, social victimization showed hyperactivation of the dorsomedial and lateral prefrontal cortex, putamen, and thalamus and increased FC of the medial-frontal–striatal–thalamic areas with the ventrolateral prefrontal cortex, insula, dorsal cingulate, and postcentral gyrus. Lastly, neuroticism, irritable temperament, and frustration scores were correlated with the magnitude of neural responses to social victimization. Our findings suggest that social victimization engages a set of regions associated with salience, emotional processing, and regulation, and these responses can be modulated by temperamental and personality traits. Full article

Background: Transcutaneous auricular vagus nerve stimulation (taVNS) is effective for treating major depressive disorder (MDD). We aimed to explore the modulating effect of prolonged longitudinal taVNS on the striatal subregions’ functional connectivity (FC) in MDD patients. Methods: Sixteen MDD patients were enrolled and treated with taVNS for 8 weeks. Sixteen healthy control subjects (HCs) were recruited without intervention. The resting-state FC (rsFC) based on striatal subregion seed points and the Hamilton Depression Scale (HAMD) were evaluated in the MDD patients and HCs at baseline and after 8 weeks. A two-way ANCOVA test was performed on each rsFC metric to obtain the (group-by-time) interactions. Results: The rsFC values between the left ventral caudate (vCa) and right ventral prefrontal cortex (vPFC), and between the right nucleus accumbens (NAc) and right dorsal medial prefrontal cortex (dmPFC) and ventrolateral prefrontal cortex (vlPFC) are lower in the MDD patients compared to the HCs at baseline, and increase following taVNS; the rsFC values between the left vCa and right, superior occipital gyrus (SOG), and between the left dorsal caudate (dCa) and right cuneus are higher in MDD patients and decrease following taVNS. Conclusions: Prolonged longitudinal taVNS can modulate the striatum rsFC with the prefrontal cortex, occipital cortex, temporal cortex, and intra-striatum, and these changes partly underlie any symptomatic improvements. The results indicate that prolonged longitudinal taVNS may produce beneficial treatment effects by modulating the cortical striatum circuitry in patients with MDD. Full article

The present study examined the evolution of the behavioral performance, subjectively perceived difficulty, and hemodynamic activity of the prefrontal cortex as a function of cognitive load during two different cognitive tasks tapping executive functions. Additionally, it investigated the relationships between these behavioral, subjective, and neuroimaging data. Nineteen right-handed young adults (18–22 years) were scanned using continuous-wave functional near-infrared spectroscopy during the performance of n-back and random number generation tasks in three cognitive load conditions. Four emitter and four receptor optodes were fixed bilaterally over the ventrolateral and dorsolateral prefrontal cortices to record the hemodynamic changes. A self-reported scale measured the perceived difficulty. The findings of this study showed that an increasing cognitive load deteriorated the behavioral performance and increased the perceived difficulty. The hemodynamic activity increased parametrically for the three cognitive loads of the random number generation task and in a two-back and three-back compared to a one-back condition. In addition, the hemodynamic activity was specifically greater in the ventrolateral prefrontal cortex than in the dorsolateral prefrontal cortex for both cognitive tasks (random number generation and n-back tasks). Finally, the results highlighted some links between cerebral oxygenation and the behavioral performance, but not the subjectively perceived difficulty. Our results suggest that cognitive load affects the executive performance and perceived difficulty and that fNIRS can be used to specify the prefrontal cortex’s implications for executive tasks involving inhibition and working memory updating. Full article