Human Prosocial Preferences Are Related to Slow-Wave Activity in Sleep.

Prosocial behavior is crucial for the smooth functioning of the society. Yet, individuals differ vastly in the propensity to behave prosocially. Here, we try to explain these individual differences under normal sleep conditions without any experimental modulation of sleep. Using a portable high-density EEG, we measured the sleep data in 54 healthy adults (28 females) during a normal night's sleep at the participants' homes. To capture prosocial preferences, participants played an incentivized public goods game in which they faced real monetary consequences. The whole-brain analyses showed that a higher relative slow-wave activity (SWA, an indicator of sleep depth) in a cluster of electrodes over the right temporoparietal junction (TPJ) was associated with increased prosocial preferences. Source localization and current source density analyses further support these findings. Recent sleep deprivation studies imply that sleeping enough makes us more prosocial; the present findings suggest that it is not only sleep duration, but particularly sufficient sleep depth in the TPJ that is positively related to prosociality. Because the TPJ plays a central role in social cognitive functions, we speculate that sleep depth in the TPJ, as reflected by relative SWA, might serve as a dispositional indicator of social cognition ability, which is reflected in prosocial preferences. These findings contribute to the emerging framework explaining the link between sleep and prosocial behavior by shedding light on the underlying mechanisms.

The neural mechanisms of identifiable victim effect in prosocial decision-making.

The phenomenon known as the "identifiable victim effect" describes how individuals tend to offer more assistance to victims they can identify with than to those who are vague or abstract. The neural underpinnings of this effect, however, remain elusive. Our study utilized functional magnetic resonance imaging to delve into how the "identifiable victim effect" influences prosocial decision-making, considering different types of helping costs, across two distinct tasks. Participants were instructed to decide whether to help a victim with personal information shown (i.e., the identifiable victim) and an unidentifiable one by costing their money (task 1) or physical effort (task 2). Behaviorally, we observed a pronounced preference in both tasks for aiding identifiable victims over anonymous ones, highlighting a robust "identifiable victim effect." On a neural level, this effect was associated with heightened activity in brain areas like the bilateral temporoparietal junction (TPJ) when participants confronted anonymous victims, potentially indicating a more intensive mentalizing process for less concrete victims. Additionally, we noted that the TPJ's influence on value judgment processes is mediated through its functional connectivity with the medial prefrontal cortex. These insights contribute significantly to our understanding of the psychological and neural dynamics underlying the identifiable victim effect.

The involvement of rTPJ in intention attribution during social decision making: A TMS study.

The mini-Ultimatum Game (mini-UG) is a bargaining game used to assess the reactions of a responder to unfair offers made by a proposer under different intentionality conditions. Previous studies employing this task showed the activation of responders' right temporoparietal junction (rTPJ), which could be related to its involvement in judgments of intentionality. To verify this hypothesis, in the present study we applied online transcranial magnetic stimulation (TMS) over the rTPJ in responders during the mini-UG, in which we manipulated intention attribution implicitly. A cover story was employed to induce participants to believe they were interacting with another agent. We expected that interfering with the rTPJ could affect the ability of responders to assume proposers' perspective, producing higher rates of rejections of unfair offers when offers are perceived as independent from responders' intentionality to inequality. Twenty-six healthy women voluntarily participated in the study. In the mini-UG, an unfair distribution of the proposer (8/2 offer) was pitted against one of three alternative offers: fair-alternative (5/5), no-alternative (8/2), hyperfair-alternative (2/8). During the task, a train of TMS pulses was delivered at proposers' offer presentation in blocks of active (rTPJ) or control (Vertex) stimulation according to an ABAB design. As expected, findings showed that rejection of the no-alternative offers was higher under TMS stimulation of the rTPJ compared with the control TMS. This effect was modulated by the degree of trustworthiness in the cover story. These data contribute defining the mechanisms and brain areas underpinning social decision making as assessed by bargaining tasks.

Neural correlates of empathy in mild cognitive impairment.

The occurrence of clinically significant changes in empathy is a matter of debate in Alzheimer's disease (AD). Altered empathic mechanisms observed in AD may be a consequence of cognitive impairment, more specifically of reduced mental flexibility and self-regulation. The present study explored possible changes in empathy for subjects in the prodromal phase of AD, namely mild cognitive impairment (MCI) due to AD, and of their neural substrates. Eighteen MCI patients and 20 healthy controls (HC) were included in the study. The Interpersonal Reactivity Index (IRI) questionnaire was administered to each participant. The IRI encompasses four factors: Perspective Taking; Fantasy; Empathic Concern; Personal Distress. MCI patients underwent a magnetic resonance imaging structural examination and were compared to 30 healthy controls (HC-MRI). A limited number of cortical and subcortical regions involved in social cognition was selected as regions of interest (ROIs). MCI individuals obtained lower scores than HC in the Perspective Taking and Fantasy subscales of the IRI, whereas they obtained higher scores on Empathic Concern. Regarding neuroimaging data, a significant correlation emerged between IRI scores and the neural measurements of different regions involved in empathy, especially covering the temporoparietal junction, which is a critical region engaged in both affective and cognitive dimensions of empathy. The results of the present study suggest that a subtle impairment in regulatory mechanisms of empathy may occur very early during the course of AD, possibly as a consequence of neuropathological changes occurring in brain regions involved in social cognition.

Altered temporoparietal junction activity during reflected self-evaluation in sub-clinical depression.

Negative self-schema is a core symptom of depression. According to social psychological theories, two types of self-evaluations play important roles in forming the negative self-view: direct self-evaluation (that is, evaluating the self directly through one's first-person perspective introspection) and reflected self-evaluation (which requires theory of mind (ToM) ability, and is evaluating the self through reflecting on a third person's perspective). Although many previous studies have investigated the processing of the direct self-evaluation in depression, few have extended research on the reflected self-evaluation. In the current study, functional magnetic resonance imaging scans were acquired in 26 dysphoric (individuals with elevated number of depressive symptoms) and 28 control participants during both direct and reflected self-evaluation tasks. Two regions of interest were defined within bilateral temporoparietal junctions (TPJs) because their significant role in ToM. Results showed that the dysphoric participants evaluated themselves more negatively than the control participants, regardless of whose perspective they were taking. More importantly, the enhanced TPJs' activations were observed in the control group during the reflected self-evaluation task versus the direct self-evaluation task, whereas no such difference was observed in the dysphoric participants. The results are interpreted in the framework of impaired ToM ability in sub-clinical depression.  General Scientific Summary (GSS) Negative self-schema is one of the core symptoms of depression. This study suggests that the negative self-schema reflects not only in direct self-evaluation (i.e. evaluating the self via one's own introspection) but also in reflected self-evaluation (i.e. evaluating the self via others' perspective). Importantly, altered TPJ activity was found during a reflected self-evaluation task among individuals with depressive symptoms. These changes in brain function might be associated with impaired ToM ability in sub-clinical depression.

Attention, awareness, and the right temporoparietal junction.

The attention schema theory posits a specific relationship between subjective awareness and attention, in which awareness is the control model that the brain uses to aid in the endogenous control of attention. In previous experiments, we developed a behavioral paradigm in human subjects to manipulate awareness and attention. The paradigm involved a visual cue that could be used to guide attention to a target stimulus. In task 1, subjects were aware of the cue, but not aware that it provided information about the target. The cue measurably drew exogenous attention to itself. In addition, implicitly, the subjects' endogenous attention mechanism used the cue to help shift attention to the target. In task 2, subjects were no longer aware of the cue. The cue still measurably drew exogenous attention to itself, yet without awareness of the cue, the subjects' endogenous control mechanism was no longer able to use the cue to control attention. Thus, the control of attention depended on awareness. Here, we tested the two tasks while scanning brain activity in human volunteers. We predicted that the right temporoparietal junction (TPJ) would be active in relation to the process in which awareness helps control attention. This prediction was confirmed. The right TPJ was active in relation to the effect of the cue on attention in task 1; it was not measurably active in task 2. The difference was significant. In our interpretation, the right TPJ is involved in an interaction in which awareness permits the control of attention.

Testosterone reduces generosity through cortical and subcortical mechanisms.

Recent evidence has linked testosterone, a major sex hormone, to selfishness in economic decision-making. Here, we aimed to investigate the neural mechanisms through which testosterone reduces generosity by combining functional MRI with pharmacological manipulation among healthy young males in a double-blind, placebo-controlled, between-subject design. After testosterone or placebo gel administration, participants performed a social discounting task in which they chose between selfish options (benefiting only the participant) and generous options (providing also some benefit to another person at a particular social distance). At the behavioral level, testosterone reduced generosity compared to the placebo. At the neural level (n = 60), the temporoparietal junction (TPJ) encoded the other-regarding value of the generous option during generous choices, and this effect was attenuated by testosterone, suggesting that testosterone reduced the consideration of other's welfare as underpinned by TPJ activity. Moreover, TPJ activity more strongly reflected individual differences in generosity in the placebo than the testosterone group. Furthermore, testosterone weakened the relation between the other-regarding value of generous decisions and connectivity between the TPJ and a region extending from the insula into the striatum. Together, these findings suggest that a network encompassing both cortical and subcortical components underpins the effects of testosterone on social preferences.

Live agent preference and social action monitoring in the macaque mid-superior temporal sulcus region.

Mentalizing, the ability to infer the mental states of others, is a cornerstone of adaptive social intelligence. While functional brain mapping of human mentalizing has progressed considerably, its evolutionary signature in nonhuman primates remains debated. The discovery that the middle part of the macaque superior temporal sulcus (mid-STS) region has a connectional fingerprint most similar to the human temporoparietal junction (TPJ)-a crucial node in the mentalizing network-raises the possibility that these cortical areas may also share basic functional properties associated with mentalizing. Here, we show that this is the case in aspects of a preference for live social interactions and in a theoretical framework of predictive coding. Macaque monkeys were trained to perform a turn-taking choice task with another real monkey partner sitting directly face-to-face or a filmed partner appearing in prerecorded videos. We found that about three-fourths of task-related mid-STS neurons exhibited agent-dependent activity, most responding selectively or preferentially to the partner's action. At the population level, activities of these partner-type neurons were significantly greater under live-partner compared to video-recorded-partner task conditions. Furthermore, a subset of the partner-type neurons responded proactively when predictions about the partner's action were violated. This prediction error coding was specific to the action domain; almost none of the neurons signaled error in the prediction of reward. The present findings highlight unique roles of the macaque mid-STS at the single-neuron level and further delineate its functional parallels with the human TPJ in social cognitive processes associated with mentalizing.

Decoding subject's own name in the primary auditory cortex.

Current studies have shown that perception of subject's own name (SON) involves multiple multimodal brain regions, while activities in unimodal sensory regions (i.e., primary auditory cortex) and their interaction with multimodal regions during the self-processing remain unclear. To answer this, we combined multivariate pattern analysis and dynamic causal modelling analysis to explore the regional activation pattern and inter-region effective connection during the perception of SON. We found that SON and other names could be decoded from the activation pattern in the primary auditory cortex. In addition, we found an excitatory effect of SON on connections from the anterior insula/inferior frontal gyrus to the primary auditory cortex, and to the temporoparietal junction. Our findings extended the current knowledge of self-processing by showing that primary auditory cortex could discriminate SON from other names. Furthermore, our findings highlighted the importance of influence of the insula on the primary auditory cortex during self-processing.

Threat-induced anxiety and selfishness in resource sharing: Behavioral and neural evidence.

In real life, it is not unusual that we face potential threats (i.e., physical stimuli and environments that may cause harm or danger) with other individuals together, yet it remains largely unknown how threat-induced anxious feelings influence prosocial behaviors such as resource sharing. In this study, we investigated this question by combining functional magnetic resonance imaging and a novel paradigm. Together with an anonymous partner, each participant faced the possibility of receiving a 10-s noise administration, which had a low or high probability to be a threat (i.e., the intensity of noise can induce a high level of unpleasantness). Each participant first reported her/his immediate feeling of anxiety about the current situation (being threatened by the unpleasant noise), then decided how to split a number of resources (which could relieve the noise) between her/him and the partner. Behavioral results revealed that the participants showed a selfish bias in the threat conditions than in the safe conditions, and that self-reported anxiety feeling significantly predicted this bias. Functional magnetic resonance imaging results revealed that: (1) the activation level of the anterior insula was correlated with self-reported anxiety and (2) the connectivity between the anterior insula and the temporoparietal junction was sensitive to the modulating effect of anxiety on the selfish bias. These findings indicate the neural correlates of the association between threat-induced anxiety and prosocial tendencies in social interactions.

Segregation of Neural Circuits Involved in Social Gaze and Non-Social Arrow Cues: Evidence from an Activation Likelihood Estimation Meta-Analysis.

Orienting attention by social gaze cues shares some characteristics with orienting attention by non-social arrow cues, but it is unclear whether they rely on similar neural mechanisms. The present ALE-meta-analysis assessed the pattern of brain activation reported in 40 single experiments (18 with arrows, 22 with gaze), with a total number of 806 participants. Our findings show that the network for orienting attention by social gaze and by non-social arrow cues is in part functionally segregated. Orienting by both types of cues relies on the activity of brain regions involved in endogenous attention (the superior frontal gyrus). Importantly, only orienting by gaze cues was also associated with the activity of brain regions involved in exogenous attention (medial frontal gyrus), processing gaze, and mental state attribution (superior temporal sulcus, temporoparietal junction).

Understanding the multidimensional cognitive deficits of logopenic variant primary progressive aphasia.

The logopenic variant of primary progressive aphasia is characterized by early deficits in language production and phonological short-term memory, attributed to left-lateralized temporoparietal, inferior parietal and posterior temporal neurodegeneration. Despite patients primarily complaining of language difficulties, emerging evidence points to performance deficits in non-linguistic domains. Temporoparietal cortex, and functional brain networks anchored to this region, are implicated as putative neural substrates of non-linguistic cognitive deficits in logopenic variant primary progressive aphasia, suggesting that degeneration of a shared set of brain regions may result in co-occurring linguistic and non-linguistic dysfunction early in the disease course. Here, we provide a Review aimed at broadening the understanding of logopenic variant primary progressive aphasia beyond the lens of an exclusive language disorder. By considering behavioural and neuroimaging research on non-linguistic dysfunction in logopenic variant primary progressive aphasia, we propose that a significant portion of multidimensional cognitive features can be explained by degeneration of temporal/inferior parietal cortices and connected regions. Drawing on insights from normative cognitive neuroscience, we propose that these regions underpin a combination of domain-general and domain-selective cognitive processes, whose disruption results in multifaceted cognitive deficits including aphasia. This account explains the common emergence of linguistic and non-linguistic cognitive difficulties in logopenic variant primary progressive aphasia, and predicts phenotypic diversification associated with progression of pathology in posterior neocortex.

Neuromodulation of the right temporoparietal junction alters amygdala functional connectivity to authority pressure.

Past historical events and experimental research have shown that complying with orders from an authority has a strong impact on harming/destructive behavior, but no one has ever looked into the potential intervention and its neural underpinning to reveal the toll of coercion. We used a paradigm of virtual obedience to authority, in which an experimenter ordered a volunteer to press a handheld button to initiate actions that carried different consequences, including harming or helping others. In this study, we scanned the brain with functional neuroimaging and applied transcranial direct current stimulation (tDCS) to modulate the activation of the right temporoparietal junction (rTPJ) in healthy volunteers in a single-blinded, sham-controlled, crossover trial with anodal, cathodal, and sham stimulation. We observed that cathodal stimulation, compared to anodal and sham stimulation, significantly reduced reaction times (RTs) to initiating harming actions. The effect of tDCS on the rTPJ, orbitofrontal cortex, and anterior cingulate cortex had opposite directions depending on coercive harming or helping actions. Cathodal tDCS-induced changes in the strength of the functional connectivity between the rTPJ and amygdala predicted the effect of cathodal tDCS on harming RTs. The findings provide evidence supporting the rTPJ having a role in coercion-induced changes in the sense of agency. Neuromodulation with tDCS might help in unveiling the power of authority and assisting in the emergence of prosocial behavior, thus shedding light on coping strategies against coercion beyond merely examining its effects.

Try to see it my way - Examining the relationship between visual perspective taking and theory of mind in frontotemporal dementia.

The behavioural variant of frontotemporal dementia (bvFTD) is characterised by pronounced alterations in social functioning, including the understanding of others' thoughts and feelings via theory of mind. The emergence of such impairments in other social disorders such as autism and schizophrenia is suggested to reflect an inability to imagine the other person's visual perspective of the world. To our knowledge, relationships between visual perspective taking and theory of mind have not previously been explored in bvFTD. Here, we sought to examine the capacity for visual perspective taking and theory of mind in bvFTD, and to establish their inter-relationships and underlying neural correlates. Fifteen bvFTD patients and 15 healthy Controls completed a comprehensive battery of perspective taking measures, comprising Level 1 ('what') and Level 2 ('how') visual perspective taking tasks, a cartoon task capturing theory of mind, and a questionnaire assessing subjective perspective taking in daily life. Compared with Controls, bvFTD patients displayed significant impairments across all perspective taking measures. These perspective taking impairments, however, were not correlated with one another in bvFTD. Region-of-interest voxel-based morphometry analyses suggested distinct neural correlates for visual perspective taking (inferior frontal gyrus) versus theory of mind (medial prefrontal cortex, precuneus), which appeared to partially overlap with those implicated in subjective perspective taking (inferior frontal gyrus, precuneus, temporoparietal junction). Despite pervasive impairments in all aspects of perspective taking in bvFTD, these did not appear to relate to one another at the behavioural or neural level in our study. Future large-scale studies manipulating discrete aspects of the tasks will help to clarify the neurocognitive mechanisms of, and relationships between, visual perspective taking and theory of mind in bvFTD, along with their real-world implications.

Insular Cortex Mediates Attentional Capture by Behaviorally Relevant Stimuli after Damage to the Right Temporoparietal Junction.

The right temporoparietal junction (rTPJ) and insula both play a key role for the processing of relevant stimuli. However, while both have been conceived as neural "switches" that detect salient events and redirect the focus of attention, it remains unclear how these brain regions interact to achieve this behavioral goal. Here, we tested human participants with focal left-hemispheric or right-hemispheric lesions in a spatial cuing task that requires participants to react to lateralized stimuli preceded by a distracter that shares or does not share a relevant feature with the target. Using machine learning to identify significant lesion-behavior relationships, we found that rTPJ damage produces distinctive, pathologically increased attentional capture, but only by relevant distracters. Functional connectivity analyses revealed that the degree of capture is positively associated with a functional connection between insula and rTPJ, together with functional isolation of the rTPJ from right dorsal prefrontal cortex (dPFC). These findings suggest a mechanistic model where the insula-rTPJ connection constitutes a crucial functional unit that breaks attentional focus upon detection of behaviorally relevant events, while the dPFC appears to attune this activity.

Developmental changes of the neural mechanisms underlying level 2 visual perspective-taking: A functional near-infrared spectroscopy study.

The ability to understand the way other people see the world differs from one's own viewpoint is referred to as ''visual perspective-taking'' (VPT). Previous studies have demonstrated the behavioral performance in level 2 VPT (VPT2), the ability to understand that two different observers can have unique visual experiences of the same scene or object depending on the observers' physical location, changes during childhood. However, the developmental aspects underlying the neural mechanisms of VPT2 remains unknown. We measured the hemodynamic responses to a VPT2 task using functional near-infrared spectroscopy, with mental rotation (MR) as a control task in 7- to 11-year-old and 11- to 16-year-old groups. In the VPT2 task, participants were required to mentally compute the perspective of a toy on the turntable from that of a doll placed in a different location from the observer. For the MR task, participants reported their perspectives after the toy was rotated. We found significantly higher oxy-hemoglobin changes during the VPT2 task than the MR task in the 7- to 11-year-old group but not in the 11- to 16-year-old group, in the right middle and superior temporal, angular gyrus and frontal regions. These findings highlight the important role of the right temporoparietal region in processing perspective, up to 11 years.

The Right Temporoparietal Junction Is Causally Associated with Embodied Perspective-taking.

A prominent theory claims that the right temporoparietal junction (rTPJ) is especially associated with embodied processes relevant to perspective-taking. In the present study, we use high-definition transcranial direct current stimulation to provide evidence that the rTPJ is causally associated with the embodied processes underpinning perspective-taking. Eighty-eight young human adults were stratified to receive either rTPJ or dorsomedial PFC anodal high-definition transcranial direct current stimulation in a sham-controlled, double-blind, repeated-measures design. Perspective-tracking (line-of-sight) and perspective-taking (embodied rotation) were assessed using a visuo-spatial perspective-taking task that required understanding what another person could see or how they see it, respectively. Embodied processing was manipulated by positioning the participant in a manner congruent or incongruent with the orientation of an avatar on the screen. As perspective-taking, but not perspective-tracking, is influenced by bodily position, this allows the investigation of the specific causal role for the rTPJ in embodied processing. Crucially, anodal stimulation to the rTPJ increased the effect of bodily position during perspective-taking, whereas no such effects were identified during perspective-tracking, thereby providing evidence for a causal role for the rTPJ in the embodied component of perspective-taking. Stimulation to the dorsomedial PFC had no effect on perspective-tracking or taking. Therefore, the present study provides support for theories postulating that the rTPJ is causally involved in embodied cognitive processing relevant to social functioning.SIGNIFICANCE STATEMENT The ability to understand another's perspective is a fundamental component of social functioning. Adopting another perspective is thought to involve both embodied and nonembodied processes. The present study used high-definition transcranial direct current stimulation (HD-tDCS) and provided causal evidence that the right temporoparietal junction is involved specifically in the embodied component of perspective-taking. Specifically, HD-tDCS to the right temporoparietal junction, but not another hub of the social brain (dorsomedial PFC), increased the effect of body position during perspective-taking, but not tracking. This is the first causal evidence that HD-tDCS can modulate social embodied processing in a site-specific and task-specific manner.

The Neural Mechanism of the Social Framing Effect: Evidence from fMRI and tDCS Studies.

As an important cognitive bias, the framing effect shows that our decision preferences are sensitive to the verbal description (i.e., frame) of options. This study focuses on the neural underpinnings of the social framing effect, which is based on decision-making regarding other people. A novel paradigm was used in which participants made a trade-off between economic benefits and the feelings of others. This decision was described as either a "harm" to, or "not helping," other persons in two conditions (Harm frame vs Help frame). Both human males and females were recruited. Participants behaved more prosocially for Harm frame compared with Help frame, resulting in a significant social framing effect. Using functional magnetic resonance imaging, Experiment 1 showed that the social framing effect was associated with stronger activation in the temporoparietal junction (TPJ), especially its right part. The functional connectivity between the right TPJ (rTPJ) and medial prefrontal cortex predicted the social framing effect on the group level. In Experiment 2, we used transcranial direct current stimulation to modulate the activity of the rTPJ and found that the social framing effect became more prominent under anodal (excitatory) stimulation, while the nonsocial framing effect elicited by the economic gain/loss gambling frame remained unaffected. The rTPJ results might be associated with moral conflicts modulated by the social consequences of an action or different levels of mentalizing with others under different frame conditions, but alternative interpretations are also worth noting. These findings could help elucidate the psychological mechanisms of the social framing effect.SIGNIFICANCE STATEMENT Previous studies have suggested that the framing effect is generated from an interaction between the amygdala and anterior cingulate cortex. This opinion, however, is based on findings from nonsocial framing tasks. Recent research has highlighted the importance of distinguishing between the social and nonsocial framing effects. The current study focuses on the social framing effect and finds out that the temporoparietal junction and its functional connectivity with the medial prefrontal cortex play a significant role. Additionally, modulating the activity of this region leads to changes in social (but not nonsocial) framing effect. Broadly speaking, these findings help understand the difference in neural mechanisms between social and nonsocial decision-making. Meanwhile, they might be illuminating to promote helping behavior in society.

Effects of non-invasive brain stimulation on visual perspective taking: A meta-analytic study.

Visual perspective taking (VPT) is a critical ability required by complex social interaction. Non-invasive brain stimulation (NIBS) has been increasingly used to examine the causal relationship between brain activity and VPT, yet with heterogeneous results. In the current study, we conducted two meta-analyses to examine the effects of NIBS of the right temporoparietal junction (rTPJ) or dorsomedial prefrontal cortex (dmPFC) on VPT, respectively. We performed a comprehensive literature search to identify qualified studies and computed the standardized effect size (ES) for each combination of VPT level (Level-1: visibility judgment; Level-2: mental rotation) and perspective (self and other). Thirteen studies (rTPJ: 12 studies, 23 ESs; dmPFC: 4 studies, 14 ESs) were included in the meta-analyses. Random-effects models were used to generate the overall effects. Subgroup analyses for distinct VPT conditions were also performed. We found that rTPJ stimulation significantly improved participants' visibility judgment from the allocentric perspective, whereas its effects on other VPT conditions are negligible. Stimulation of dmPFC appeared to influence Level-1 performance from the egocentric perspective, although this finding was only based on a small number of studies. Notably, contrary to some theoretical models, we did not find strong evidence that these regions are involved in Level-2 VPT with a higher requirement of mental rotation. These findings not only advance our understanding of the causal roles of the rTPJ and dmPFC in VPT, but also reveal that the efficacy of NIBS on VPT is relatively small. Additionally, researchers should also be cautious about the potential publication bias and selective reporting.

Prevent breaking bad: A proof of concept study of rebalancing the brain's rumination circuit with real-time fMRI functional connectivity neurofeedback.

Rumination, repetitively thinking about the causes, consequences, and one's negative affect, has been considered as an important factor of depression. The intrusion of ruminative thoughts is not easily controlled, and it may be useful to visualize one's neural activity related to rumination and to use that information to facilitate one's self-control. Real-time fMRI neurofeedback (rtfMRI-nf) enables one to see and regulate the fMRI signal from their own brain. This proof-of concept study utilized connectivity-based rtfMRI-nf (cnf) to normalize brain functional connectivity (FC) associated with rumination. Healthy participants were instructed to brake or decrease FC between the precuneus and the right temporoparietal junction (rTPJ), associated with high levels of rumination, while engaging in a self-referential task. The cnf group (n = 14) showed a linear decrease in the precuneus-rTPJ FC across neurofeedback training (trend [112] = -0.180, 95% confidence interval [CI] -0.330 to -0.031, while the sham group (n = 14) showed a linear increase in the target FC (trend [112] = 0.151, 95% CI 0.017 to 0.299). Although the cnf group showed a greater reduction in state-rumination compared to the sham group after neurofeedback training (p < .05), decoupled precuneus-rTPJ FC did not predict attenuated state-rumination. We did not find any significant aversive effects of rtfMRI-nf in all study participants. These results suggest that cnf has the capacity to influence FC among precuneus and rTPJ of a ruminative brain circuit. This approach can be applied to mood and anxiety patients to determine the clinical benefits of reduction in maladaptive rumination.