Self-referential processing in our brain--a meta-analysis of imaging studies on the self

The neural basis of self-ambivalence: an ERP study

The primary objective of this study was to investigate the neural basis of self-ambivalence, a phenomenon firmly established by behavioral research but whose underlying brain mechanisms have been less explored. Employing EEG methods and a modified self-reference paradigm, we analyzed event-related potentials using a linear mixed model to determine whether self-ambivalence processing exhibits a distinct neural representation. The results indicated that self-ambivalence processing primarily affected the late components (N2, N450, and P3), with N450 activation in the midline brain regions showing a significant positive correlation with scores on the Dialectical Self Scale. This finding suggests that individuals with higher levels of self-ambivalence may engage in more extensive processing of self-ambivalent information. The current study confirms the importance of the cortical midline in self-ambivalence and provides the first evidence of a distinct EEG representation of self-ambivalence processing. These findings contribute to our understanding of the neural mechanisms underlying self-ambivalence and highlight the potential role of individual differences in shaping the neural processing of self-ambivalent information.

Beyond Dehumanized Gender Identity: Critical Reflection on Neuroscience, Power Relationship and Law

The gender movement comprising feminist and queer group movements addressed various issues of prejudices in the legal domain. This article discusses the question of power in the context of neuroscience, gender, and law. It elaborates on how the stereotypical view corresponding to the mythology and parasitic view prevalent in history was made as fact through discourse construction and scientific appropriations. Thus, identifying the simplistic psychology of one's agency, societal framing of the methods of socialization, and institutionalizing the common sense of inferiority about one's identity including the process of internalization along with the biological inferiority has maintained the gap in gender equality. The article further elaborates how gender and self-image have taken a turn with the voices of social change and critical engagement with the reified gender categories.

Psychophysiological indexes in the detection of deception: A systematic review

Robust evidence on deception detection highlights that humans perform at chance level, especially when a truth-default cognitive threshold is crossed by the deceiver. This systematic review examined whether identification of deceptive stimuli elicits specific physiological responses in the detectors of deception. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, five databases were searched for human studies that evaluate physiological reactivity to deceptive stimuli, along with behavioural responses. Eleven studies (thirteen experiments) were included in a qualitative synthesis. Results show that deception detection is associated with higher activity in the prefrontal cortex and temporal lobe, with a specific involvement of the temporoparietal junction, alongside the cerebellum and cingulate cortex. Specific changes in other physiological activities (i.e., heart rate, skin temperature, motor excitability) also seem to be differently associated with the detection of deception. This review suggests that detecting deception should be considered a complex decision-making process and indicates that specific physiological activity is present across different types of deceptive stimuli. Implications are promising for further developments in security and forensic sciences.

Investigating the properties of fMRI-based signature of recognizing one's own face

Multivariate pattern analysis has revolutionized the field of neuroimaging. Many hope it will help elucidate how mental states are encoded in brain activity, though others caution that such optimism may be premature. In this study, we sought to identify an fMRI-based signature of a relatively simple but basic feeling of recognizing one's own face (SFRS), and to examine its properties. The fMRI data were acquired while participants attempted to recognize themselves in images of morphed faces. A series of binary classifications ('self' vs. 'not self') showed that the localization of most prognostic areas is consistent with published results based on univariate analysis. SFRS response classified between 'self' and 'not self' with 100 % accuracy and could accurately predict the morphing stages of presented face images. Mediation analyses showed that SFRS response acted as a mediator between the proportions of self in images and the decision to accept a given image as self. The relative insensitivity of SFRS to spatial smoothing and comparable predictive performance of a small subset of randomly selected voxels allow us to conclude that the information necessary to distinguish between the two mental states must be derived from the whole brain, and that this information is spatially smooth.

Beyond the Positivity Bias: The Processing and Integration of Self-Relevant Feedback Is Driven by Its Alignment With Pre-Existing Self-Views

Our self-concept is constantly faced with self-relevant information. Prevailing research suggests that information's valence plays a central role in shaping our self-views. However, the need for stability within the self-concept structure and the inherent alignment of positive feedback with the pre-existing self-views of healthy individuals might mask valence and congruence effects. In this study (N = 30, undergraduates), we orthogonalized feedback valence and self-congruence effects to examine the behavioral and electrophysiological signatures of self-relevant feedback processing and self-concept updating. We found that participants had a preference for integrating self-congruent and dismissing self-incongruent feedback, regardless of its valence. Consistently, electroencephalography results revealed that feedback congruence, but not feedback valence, is rapidly detected during early processing stages. Our findings diverge from the accepted notion that self-concept updating is based on the selective incorporation of positive information. These findings offer novel insights into self-concept dynamics, with implications for the understanding of psychopathological conditions.

Repetitive negative thinking and suicidal ideation in internalizing psychopathologies: A replication study

Suicidal ideation (SI), a risk factor for suicide, is prevalent in internalizing psychopathologies, including depression and anxiety. Rumination and worry are well-studied repetitive negative thinking (RNT) constructs implicated in internalizing psychopathologies. These constructs have shared and distinct characteristics. However, the relationship between rumination and worry and their associations with SI are not fully understood in clinical samples. The present study used correlational and regression analysis to evaluate these relationships as a secondary data analysis in treatment-seeking participants with internalizing psychopathologies in two independent samples (Study 1:n = 143; Study 2:n = 133). Results showed about half of the participants endorsed SI (Study 1:n = 79; Study 2:n = 71). Correlations revealed a significant, positive relationship between rumination and worry. Regression results with SI as the dependent variable showed rumination significantly positively corresponded with SI in both studies. Post-hoc partial correlations controlling for symptom severity (depression, anxiety), worry, and age showed the rumination-SI relationship was maintained in both studies. Findings for worry and SI were inconsistent between studies. Findings indicate rumination, but not worry, could be a stable, unique contributor to SI in internalizing psychopathologies. It may be useful to incorporate RNT into suicide risk assessment for individuals with internalizing conditions.

Deciphering the neural responses to a naturalistic persuasive message

Effective health promotion may benefit from understanding how persuasion emerges. While earlier research has identified brain regions implicated in persuasion, these studies often relied on event-related analyses and frequently simplified persuasive communications. The present study investigates the neural basis of valuation change induced by a persuasive healthy eating call, employing naturalistic stimuli. Fifty healthy participants performed two blocks of a bidding task, in which they had to bid on sugar-containing, sugar-free, and nonedible products during functional MRI. In between the two blocks, they listened to a persuasive healthy eating call that influenced their bidding behavior. Intriguingly, participants who resisted persuasion exhibited increased synchronization of brain activity during listening in several regions, including default mode network structures. Additionally, intersubject functional connectivity among these brain regions was found to be weaker in persuaded individuals. These results emphasize the individualized nature of processing persuasive messages, challenging conventional interpretations of synchronized neural activity. Our findings support the emerging practice of tailoring persuasive messages in health promotion campaigns.

Increased Insular Functional Connectivity During Repetitive Negative Thinking in Major Depression and Healthy Volunteers

Background

Repetitive negative thinking (RNT) in major depressive disorder (MDD) involves persistent focus on negative self-related experiences. Resting-state fMRI shows that the functional connectivity (FC) between the insula and the superior temporal sulcus is critical to RNT intensity. This study examines how insular FC patterns differ between resting-state and RNT-induction in MDD and healthy participants (HC).

Methods

Forty-one individuals with MDD and twenty-eight HCs (total n=69) underwent resting-state and RNT-induction fMRI scans. Seed-to-whole brain analysis using insular subregions as seeds was performed.

Results

No diagnosis-by-run interaction effects were observed across insular subregions. MDD participants showed greater FC between bilateral anterior, middle, and posterior insular regions and the cerebellum (z = 4.31 to 6.15). During RNT-induction, both MDD and HC participants demonstrated increased FC between bilateral anterior and middle insula and key brain regions, including prefrontal cortices, parietal lobes, posterior cingulate cortex, and medial temporal gyrus, encompassing the STS (z = 4.47 to 8.31). Higher trait-RNT was associated with increased FC between the right dorsal anterior and middle insula and regions in the DMN and salience network in MDD participants (z = 4.31 to 6.15). Greater state-RNT scores were linked to increased FC in similar insular regions, the bilateral angular gyrus and right middle temporal gyrus (z = 4.47 to 8.31).

Conclusions

Hyperconnectivity in insula subregions during active rumination, especially involving the DMN and salience network, supports theories of heightened self-focused and negative emotional processing in depression. These findings emphasize the neural basis of RNT when actively elicited in MDD.

Meditation and interoception: a conceptual framework for the narrative and experiential self

The concept of the self is complex and there is no consensus on what the self is. However, there are emerging patterns in the literature that point to two different selves, the narrative and experiential self. The narrative self refers to a conceptual or representational knowledge of the self that extends across time and manifests in self-reflection and personality assessments. The experiential self refers to first-person perception, moment-to-moment awareness, embodiment, and a sense of agency. These two selves are reliably linked to two distinct neural circuits, the default mode network (DMN) and the insula and salience network (SN). One of the consistent themes in the meditative and mindfulness literature is a change in the perspective of the self. In this paper, I will review how meditation alters those neural circuits providing a plausible mechanism that can explain the changes in the self. I also propose a rudimentary conceptual framework to account for some of the mixed results found throughout meditation literature.

Disturbance at the self-other boundary in schizophrenia: Linking phenomenology to clinical neuroscience

In this selective review, we describe the current neuroscientific literature on disturbances of the self-other boundary in schizophrenia as they relate to structural and experiential aspects of the self. Within these two broad categories, the structural self includes body ownership and agency, and the experiential self includes self-reflection, source monitoring, and self-referential and autobiographical memory. Further, we consider how disturbances in these domains link to the phenomenology of schizophrenia. We identify faulty internal predictive coding as a potential mechanism of disturbance in body ownership and agency, which results in susceptibility to bias (over- or under-attributing outcomes to one's own actions or intentions). This is reflected in reduced activity in the temporoparietal junction (TPJ), a heteromodal association area implicated in several aspects of self-other processing, as well as reduced fronto-parietal functional connectivity. Deficits of the experiential self in schizophrenia may stem from a lack of salience of self-related information, whereby the mental representation of self is not as rich as in healthy controls and therefore does not result in the same level of privileged processing. As a result, memory for self-referential material and autobiographical memory processes is impaired, which hinders creation of a cohesive life narrative. Impairments of the experiential self implicate abnormal activation patterns along the cortical midline, including medial prefrontal cortex and posterior cingulate/precuneus, as well as TPJ. In fact, TPJ appears to be involved in all the reviewed aspects of the self-other disturbance. We conclude with suggestions for future work, including implications for interventions with critical timing considerations.

The temporal profile of self-prioritization

Personal relevance exerts a powerful influence on decisional processing, such that arbitrary stimuli associated with the self are classified more rapidly than identical material linked with other people. Notwithstanding numerous demonstrations of this facilitatory effect, it remains unclear whether self-prioritization is a temporally stable outcome of decision-making. Accordingly, using a shape-label matching task in combination with computational modeling, the current experiment investigated this matter. The results were informative. First, regardless of the target of comparison (i.e., friend or stranger), self-prioritization was a persistent product of decision-making across the testing session. Second, a variant of the standard drift diffusion model in which decisional boundaries collapsed gradually over the course of the task best fit the observed data. Third, whereas the efficiency of stimulus processing increased for other-related stimuli during the task, it decreased for self-related material. Collectively, these findings advance understanding of the temporal profile of self-prioritization.

The ownership memory self-reference effect shifts recognition criterion but not recognition sensitivity

Information referenced to the self is retrieved more accurately than information referenced to others, known as the memory self-reference effect. It is unclear, however, whether social context (identity of the other) or task factors alter decision-making processes. In a virtual object allocation task, female participants sorted objects into their own or another's (stranger or mother) basket based on a colour cue. Subsequently, they performed a recognition memory task in which they first indicated whether each object was old or new, and then whether it had been allocated to themselves or to the other. We obtained owner-specific hit rates and false-alarm rates and applied signal detection theory to derive separate recognition sensitivity (d') and recognition criterion parameters (c) for self- and other-owned objects. While there was no clear evidence of a recognition self-reference effect, or a change in sensitivity, participants adopted a more conservative recognition criterion for self- compared with other-owned objects, and particularly when the other-referent was the participant's mother compared with the stranger. Moreover, when discriminating whether the originally presented objects were self- or other-owned, participants were biased toward ascribing ownership to the 'other'. We speculate that these findings reflect ownership-based changes in decisional processing during the recognition memory self-reference paradigm.

Neuroimaging evidence of disturbed self-appraisal in posttraumatic stress disorder: A systematic review

BACKGROUND

The experience of self-hood in posttraumatic stress disorder (PTSD) is altered cognitively and somatically. Dysfunctional negative cognitions about the self are a central mechanism of PTSD symptomatology and treatment. However, while higher-order brain models of disturbances in self-appraisal (i.e., cognitive processes relating to evaluating the self) have been examined in other psychiatric disorders, it is unclear how normative brain function during self-appraisal is impaired in PTSD.

METHODS

This paper presents a PRISMA systematic review of functional neuroimaging studies (n = 5), to establish a neurobiological account of how self-appraisal processes are disturbed in PTSD. The review was prospectively registered with PROSPERO (CRD42023450509).

RESULTS

Self-appraisal in PTSD is linked to disrupted activity in core self-processing regions of the Default Mode Network (DMN); and regions involved in cognitive control and emotion regulation, salience and valuation.

LIMITATIONS

Because self-appraisal in PTSD is relatively under-studied, only a small number of studies could be included for review. Cross-study heterogeneity in analytic approaches and trauma-exposure history prohibited a quantitative meta-analysis.

CONCLUSIONS

This paper proposes a mechanistic account of how neural dysfunctions may manifest clinically in PTSD and inform targeted selection of appropriate treatment options. We present a research agenda for future work to advance the field.

Neural correlates of harm avoidance: a multimodal meta-analysis of brain structural and resting-state functional neuroimaging studies

Harm avoidance (HA) is a Cloninger personality trait that describes behavioural inhibition to avoid aversive stimuli. It serves as a predisposing factor that contributes to the development of mental disorders such as anxiety and major depressive disorder. Neuroimaging research has identified some brain anatomical and functional correlates of HA, but reported findings are inconsistent. We therefore conducted a multimodal meta-analysis of whole-brain structural and resting-state functional neuroimaging studies to identify the most stable neural substrate of HA. Included were a total of 10 structural voxel-based morphometry studies (11 datasets) and 13 functional positron emission tomography or single photon emission computed tomography studies (16 datasets) involving 3053 healthy participants without any psychiatric or neurological disorders evaluated for HA using the Three-Dimensional Personality Questionnaire (TPQ) or the Temperament and Character Inventory (TCI). The meta-analysis revealed brain volumetric correlates of HA in parietal and temporal cortices, and resting-state functional correlates in prefrontal, temporal and parietal gray matter. Volumetric and functional correlates co-occurred in the left superior frontal gyrus and left middle frontal gyrus, and were dissociated in the left rectus gyrus. Our meta-analysis is the first study to give a comprehensive picture of the structural and functional correlates of HA, a contribution that may help bridge the grievous gap between the neurobiology of HA and the pathogenesis, prevention and treatment of HA-related mental disorders.

Self-construal modulates default mode network connectivity in refugees with PTSD

BACKGROUND

While self-construal and posttraumatic stress disorder (PTSD) are independently associated with altered self-referential processes and underlying default mode network (DMN) functioning, no study has examined how self-construal affects DMN connectivity in PTSD.

METHODS

A final sample of 93 refugee participants (48 with DSM-5 PTSD or sub-syndromal PTSD and 45 matched trauma-exposed controls) completed a 5-minute resting state fMRI scan to enable the observation of connectivity in the DMN and other core networks. A self-construal index was calculated by substracting scores on the collectivistic and individualistic sub-scales of the Self Construal Scale.

RESULTS

Independent components analysis identified 9 active networks-of-interest, and functional network connectivity was determined. A significant interaction effect between PTSD and self-construal index was observed in the anterior ventromedial DMN, with spatial maps localizing this to the left ventromedial prefrontal cortex (vmPFC), extending to the ventral anterior cingulate cortex. This effect revealed that connectivity in the vMPFC showed greater reductions in those with PTSD with higher levels of collectivistic self-construal.

LIMITATIONS

This is an observational study and causality cannot be assumed. The specialized sample of refugees means that the findings may not generalize to other trauma-exposed populations.

CONCLUSIONS

Such a finding indicates that self-construal may shape the core neural architecture of PTSD, given that functional disruptions to the vmPFC underpin the core mechanisms of extinction learning, emotion dysregulation and self-referential processing in PTSD. Results have important implications for understanding the universality of neural disturbances in PTSD, and suggest that self-construal could be an important consideration in the assessment and treatment of post-traumatic stress reactions.

A multi-modal assessment of self-knowledge in adolescents with non-suicidal self-injury: a research domains criteria (RDoC) study

BACKGROUND

Adolescence is a critical period for brain development, consolidation of self-understanding, and onset of non-suicidal self-injury (NSSI). This study evaluated the RDoC (Research Domain Criteria) sub-construct of Self-Knowledge in relation to adolescent NSSI using multiple units of analysis.

METHODS

One hundred and sixty-four adolescents assigned female at birth (AFAB), ages 12-16 years with and without a history of NSSI entered a study involving clinical assessment and magnetic resonance imaging (MRI), including structural, resting-state functional MRI (fMRI), and fMRI during a self-evaluation task. For imaging analyses, we used an a priori defined Self Network (anterior cingulate, orbitofrontal, and posterior cingulate cortices; precuneus). We first examined interrelationships among multi-level Self variables. We then evaluated the individual relationships between NSSI severity and multi-level Self variables (self-report, behavior, multi-modal brain Self Network measures), then conducted model testing and multiple regression to test how Self variables (together) predicted NSSI severity.

RESULTS

Cross-correlations revealed key links between self-reported global self-worth and self-evaluation task behavior. Individually, greater NSSI severity correlated with lower global self-worth, more frequent and faster negative self-evaluations, lower anterior Self Network activation during self-evaluation, and lower anterior and posterior Self Network resting-state connectivity. Multiple regression analysis revealed the model including multi-level Self variables explained NSSI better than a covariate-only model; the strongest predictive variables included self-worth, self-evaluation task behavior, and resting-state connectivity.

CONCLUSIONS

Disruptions in Self-Knowledge across multiple levels of analysis relate to NSSI in adolescents. Findings suggest potential neurobiological treatment targets, potentially enhancing neuroplasticity in Self systems to facilitate greater flexibility (more frequently positive) of self-views in AFAB adolescents.

Longitudinal Analysis of Brain Function-Structure Dependencies in 22q11.2 Deletion Syndrome and Psychotic Symptoms

BACKGROUND

Compared with conventional unimodal analysis, understanding how brain function and structure relate to one another opens a new biologically relevant assessment of neural mechanisms. However, how function-structure dependencies (FSDs) evolve throughout typical and abnormal neurodevelopment remains elusive. The 22q11.2 deletion syndrome (22q11.2DS) offers an important opportunity to study the development of FSDs and their specific association with the pathophysiology of psychosis.

METHODS

Previously, we used graph signal processing to combine brain activity and structural connectivity measures in adults, quantifying FSD. Here, we combined FSD with longitudinal multivariate partial least squares correlation to evaluate FSD alterations across groups and among patients with and without mild to moderate positive psychotic symptoms. We assessed 391 longitudinally repeated resting-state functional and diffusion-weighted magnetic resonance images from 194 healthy control participants and 197 deletion carriers (ages 7-34 years, data collected over a span of 12 years).

RESULTS

Compared with control participants, patients with 22q11.2DS showed a persistent developmental offset from childhood, with regions of hyper- and hypocoupling across the brain. Additionally, a second deviating developmental pattern showed an exacerbation during adolescence, presenting hypocoupling in the frontal and cingulate cortices and hypercoupling in temporal regions for patients with 22q11.2DS. Interestingly, the observed aggravation during adolescence was strongly driven by the group with positive psychotic symptoms.

CONCLUSIONS

These results confirm a central role of altered FSD maturation in the emergence of psychotic symptoms in 22q11.2DS during adolescence. The FSD deviations precede the onset of psychotic episodes and thus offer a potential early indication for behavioral interventions in individuals at risk.

Same Same, But Different: Brain Areas Underlying the Learning from Repetitive Episodic Prediction Errors

Prediction errors (PEs) function as learning signals. It is yet unclear how varying compared to repetitive PEs affect episodic memory in brain and behavior. The current study investigated cerebral and behavioral effects of experiencing either multiple alternative versions ("varying") or one single alternative version ("repetitive") of a previously encoded episode. Participants encoded a set of episodes ("originals") by watching videos showing toy stories. During scanning, participants either experienced originals, one single, or multiple alternative versions of the previously encoded episodes. Participants' memory performance was tested through recall of original objects. Varying and repetitive PEs revealed typical brain responses to the detection of mismatching information including inferior frontal and posterior parietal regions, as well as hippocampus, which is further linked to memory reactivation, and the amygdala, known for modulating memory consolidation. Furthermore, experiencing varying and repetitive PEs triggered distinct brain areas as revealed by direct contrast. Among others, experiencing varying versions triggered activity in the caudate, a region that has been associated with PEs. In contrast, repetitive PEs activated brain areas that resembled more those for retrieval of originally encoded episodes. Thus, ACC and posterior cingulate cortex activation seemed to serve both reactivating old and integrating new but similar information in episodic memory. Consistent with neural findings, participants recalled original objects less accurately when only presented with the same, but not varying, PE during fMRI. The current findings suggest that repeated PEs interact more strongly with a recalled original episodic memory than varying PEs.

Neural correlates of individual differences in moral identity and its positive moral function

Moral identity is an important moral variable which has positive moral functions, such as contributing to prosocial behaviours, reducing antisocial behaviours, and resisting the risk factors of antisocial behaviours. However, little is known about the neural correlates of moral identity and the neural basis of the effect of moral identity on the risk factors of antisocial behaviours, including moral disengagement. In this study, we explored these issues in 142 college students by estimating the regional homogeneity (ReHo) through resting-state functional magnetic resonance imaging (fMRI). The whole-brain correlation analyses found that higher internalized moral identity was correlated with higher ReHo in the precuneus. Furthermore, the ReHo in the precuneus was negatively correlated with moral disengagement, suggesting positive moral functions of the neural mechanisms of moral identity. These findings deepen our understanding of individual differences in moral identity and provide inspiration for the education of moral identity and the intervention for moral disengagement from the perspective of the brain.

Neural rhythms of narcissism: Facets of narcissism are associated with different neural sources in resting-state EEG

Trait narcissism is characterized by significant heterogeneity across individuals. Despite advances in the conceptualization of narcissism, including the increasing recognition that narcissism is a multidimensional construct, the sources of this heterogeneity remain poorly understood. Here, we used a neural trait approach to help better understand "how," and shed light on "why," individuals vary in facets of trait narcissism. Participants (N = 58) first completed personality measures, including the Narcissistic Personality Inventory (NPI), and then in a second session sat passively while resting-state electroencephalography (rs-EEG) was recorded. We then regressed source-localized rs-EEG activity on the distinct facets of narcissism: Grandiose Exhibitionism (GE), Entitlement/Exploitativeness (EE), and Leadership/Authority (LA). Results revealed that each facet was associated with different (though sometimes overlapping) neural sources. Specifically, GE was associated with reduced activation in the dorsomedial prefrontal cortex (DMPFC). EE was associated with reduced activation in the DMPFC and right lateral PFC. LA was associated with increased activation in the left anterior temporal cortex. These findings support the idea that trait narcissism is a multidimensional construct undergirded by individual differences in neural regions related to social cognition (the DMPFC), self-regulation (right lateral PFC), and self-referential processing (left anterior temporal cortex).

Abnormal functional connectivity of the putamen in obsessive-compulsive disorder

The putamen has been proposed to play a critical role in the development of obsessive-compulsive disorder (OCD). The primary objective of this study was to examine the resting-state regional activity and functional connectivity patterns of the putamen in individuals diagnosed with OCD. To achieve this, we employed resting-state functional magnetic resonance imaging (rs-fMRI) to collect data from a sample of 45 OCD patients and 53 healthy control participants. We aimed to use the regional amplitude of low-frequency fluctuation (ALFF) analysis to generate the ROI masks of the putamen and then conduct the whole brain functional connectivity of the putamen in individuals with OCD. Compared to controls, the OCD group demonstrated decreased ALFF in bilateral putamen. The right putamen also displayed decreased FC with the left putamen extending to the inferior frontal gyrus (IFG), bilateral precuneus extending to calcarine, the right middle occipital cortex extending to the right middle temporal cortex, and the left middle occipital gyrus. The decreased connectivity between the right putamen and the left IFG was negatively correlated with Yale-Brown Obsessive Compulsive scale (Y-BOCS) Obsession Scores. This study aimed to reveal the putamen changes in resting-state activity and connectivity in OCD patients, highlighting the significance of aberrant ALFF/FC of the putamen is a key characteristic of OCD.

The Effects of Heart Rhythm Meditation on Vagal Tone and Well-being: A Mixed Methods Research Study

Many studies have examined the effects of meditation practice focused on the normal breath on vagal tone with mixed results. Heart Rhythm Meditation (HRM) is a unique meditation form that engages in the deep slow full breath, and puts the focus of attention on the heart. This form of breathing likely stimulates the vagus nerve with greater intensity. The purpose of this study was (a) to examine how the practice of HRM affects vagal activity as measured by heart rate variability (HRV); and (b) to examine how it affects participants' well-being. 74 participants signed consent agreeing to: (a) take a six-week course to learn the practice of HRM; (b) engage in a daily practice for 10 weeks; (c) have their heart rate variability read through ECG technology and to take two validated well-being instruments at the beginning and end of the 10 weeks; and (d) participate in a focus group interview examining their perceptions of how the practice affected their well-being. 48 participants completed the study. Quantitative findings show the effect of the practice of HRM approached significance for multiple measures of HRV and vagal tone. An increase in well-being scores for those who did the meditation more than 10-minutes per day did meet statistical significance. Qualitative data indicate: (a) the positive effects of HRM on stress and well-being; (b) the development of a more expanded sense of self; and (c) an increased awareness of the interconnection of the body-heart-emotions and HRM's role in emotion regulation.

Shared and distinctive brain networks underlying trait and state rumination

Although trait and state rumination play a central role in the exacerbation of negative affect, evidence suggests that they are weakly correlated and exert distinct influences on emotional reactivity to stressors. Whether trait and state rumination share a common or exhibit distinct neural substrate remains unclear. In this study, we utilized functional near-infrared spectroscopy (fNIRS) combined with connectome-based predictive modeling (CPM) to identify neural fingerprints associated with trait and state rumination. CPM identified distinctive functional connectivity (FC) profiles that contribute to the prediction of trait rumination, primarily involving FC within the default mode network (DMN) and the dorsal attention network (DAN) as well as FC between the DMN, control network (CN), DAN, and salience network (SN). Conversely, state rumination was predominantly associated with FC between the DMN and CN. Furthermore, the predictive features of trait rumination can be robustly generalized to predict state rumination, and vice versa. In conclusion, this study illuminates the importance of both DMN and non-DMN systems in the emergence and persistence of rumination. While trait rumination was associated with stronger and broader FC than state rumination, the generalizability of the predictive features underscores the presence of shared neural mechanisms between the two forms of rumination. These identified connectivity fingerprints may hold promise as targets for innovative therapeutic interventions aimed at mitigating rumination-related negative affect.

Neuroimaging of autobiographical memory in dementia with Lewy bodies: a story of insula

Although deficits in learning and retrieving new information are well characterized in dementia with Lewy bodies, autobiographical memory has never been explored in this disease. Yet, autobiographical memory impairments are a pervasive feature of dementia, well characterized in other neurodegenerative diseases. Moreover, autobiographical memory corresponds to an extension over time of the self, which we hypothesize is altered in dementia with Lewy bodies and impairment of which could be linked to the insular atrophy occurring from an early stage of the disease. In this study, we sought to characterize autobiographical memory impairments and explore their neural correlates in dementia with Lewy bodies, on the assumption that insular damage could impact the self, including its most elaborate components, such as autobiographical memory. Twenty patients with prodromal to mild dementia with Lewy bodies were selected to participate in this exploratory study along with 20 healthy control subjects. The Autobiographical Interview was used to assess autobiographical memory. Performances were compared between patients and control subjects, and an analysis across life periods and recall conditions was performed. 3D magnetic resonance images were acquired for all participants, and correlational analyses were performed in the patient group using voxel-based morphometry. The behavioural results of the Autobiographical Interview showed that autobiographical memory performances were significantly impaired in dementia with Lewy body patients compared to control subjects in a temporally ungraded manner, for both the free recall and the specific probe conditions (P < 0.0001), though with greater improvement after probing in the patient group. Furthermore, autobiographical memory impairments were correlated with grey matter volume within right insular cortex, temporoparietal junction, precuneus, putamen, left temporal cortex, bilateral parahippocampus and cerebellum, using a threshold of P = 0.005 uncorrected. The behavioural results confirm the existence of temporally ungraded autobiographical memory impairments in dementia with Lewy bodies, from the early stage of the disease. As we expected, neuroimaging analysis revealed a role for the insula and the precuneus in autobiographical memory retrieval, two regions associated with elementary aspects of the self, among other brain regions classically associated with autobiographical memory, such as medial temporal lobe and temporoparietal junction. Our findings provide important insights regarding the involvement of the insula in the self and suggest that insular damage could lead to a global collapse of the self, including its more elaborated components, such as autobiographical memory.

Self-compassion, self-referential caudate circuitry, and adolescent suicide ideation

Suicide is the second leading cause of death in youth, and depression is a strong proximal predictor of adolescent suicide. It is important to identify psychological factors that may protect against suicide ideation in depressed adolescents. Self-compassion may be such a factor. Converging evidence indicates the inverse association between self-compassion and suicide ideation, but the neural mechanisms underlying their link remain unknown. Because self-referential caudate activity is associated with both self-compassion and suicide ideation, its functional connectivity might explain their relationship. In this study, we examined the relationship between self-compassion and caudate functional connectivity during self-appraisals, a typical self-referential paradigm, and their associations with suicide ideation in both depressed and healthy youth. In the scanner, 79 depressed youth and 36 healthy controls evaluated, from various perspectives, whether phrases they heard were self-descriptive. Self-compassion and suicide ideation were rated with self-report and interview-based measures. We found that self-compassion was associated with stronger left caudate functional connectivity with bilateral posterior superior temporal sulcus/temporoparietal junction, the left middle temporal gyrus (MTG), and the left middle occipital gyrus during positive versus negative self-appraisals. Stronger left caudate connectivity with the left MTG explained the association between higher self-compassion and lower suicide ideation, even controlling for non-suicide ideation depression severity, anxiety severity, and non-suicidal self-injurious behavior. The findings suggest that the left caudate to MTG connectivity during positive versus negative self-referential processing could be a biomarker to be targeted by neural stimulation interventions for reducing suicide ideation in depressed youth, combined with self-compassion interventions.

Cross-regional coordination of activity in the human brain during autobiographical self-referential processing

For the human brain to operate, populations of neurons across anatomical structures must coordinate their activity within milliseconds. To date, our understanding of such interactions has remained limited. We recorded directly from the hippocampus (HPC), posteromedial cortex (PMC), ventromedial/orbital prefrontal cortex (OFC), and the anterior nuclei of the thalamus (ANT) during two experiments of autobiographical memory processing that are known from decades of neuroimaging work to coactivate these regions. In 31 patients implanted with intracranial electrodes, we found that the presentation of memory retrieval cues elicited a significant increase of low frequency (LF < 6 Hz) activity followed by cross-regional phase coherence of this LF activity before select populations of neurons within each of the four regions increased high-frequency (HF > 70 Hz) activity. The power of HF activity was modulated by memory content, and its onset followed a specific temporal order of ANT→HPC/PMC→OFC. Further, we probed cross-regional causal effective interactions with repeated electrical pulses and found that HPC stimulations cause the greatest increase in LF-phase coherence across all regions, whereas the stimulation of any region caused the greatest LF-phase coherence between that particular region and ANT. These observations support the role of the ANT in gating, and the HPC in synchronizing, the activity of cortical midline structures when humans retrieve self-relevant memories of their past. Our findings offer a fresh perspective, with high temporal fidelity, about the dynamic signaling and underlying causal connections among distant regions when the brain is actively involved in retrieving self-referential memories from the past.

Brain Networks, Neurotransmitters and Psychedelics: Towards a Neurochemistry of Self-Awareness

PURPOSE OF REVIEW

Self-awareness can be defined as the capacity of becoming the object of one's own awareness and, increasingly, it has been the target of scientific inquiry. Self-awareness has important clinical implications, and a better understanding of the neurochemical basis of self-awareness may help clarifying causes and developing interventions for different psychopathological conditions. The current article explores the relationship between neurochemistry and self-awareness, with special attention to the effects of psychedelics.

RECENT FINDINGS

The functioning of self-related networks, such as the default-mode network and the salience network, and how these are influenced by different neurotransmitters is discussed. The impact of psychedelics on self-awareness is reviewed in relation to specific processes, such as interoception, body ownership, agency, metacognition, emotional regulation and autobiographical memory, within a framework based on predictive coding. Improved outcomes in emotional regulation and autobiographical memory have been observed in association with the use of psychedelics, suggesting higher-order self-awareness changes, which can be modulated by relaxation of priors and improved coping mechanisms linked to cognitive flexibility. Alterations in bodily self-awareness are less consistent, being potentially impacted by doses employed, differences in acute/long-term effects and the presence of clinical conditions. Future studies investigating the effects of different molecules in rebalancing connectivity between resting-state networks may lead to novel therapeutic approaches and the refinement of existing treatments.

Naturalistic use of psychedelics does not modulate processing of self-related stimuli (but it might modulate attentional mechanisms): An event-related potentials study

Classic psychedelics are able to profoundly alter the state of consciousness and lead to acute experiences of ego dissolution - the blurring of the distinction between representations of self and the external world. However, whether repeated use of psychedelics is associated with more prolonged and permanent modifications to the concept of self remains to be investigated. Therefore, we conducted a preregistered, cross-sectional study in which experienced psychedelics users (15 or more lifetime experiences with psychedelics; N = 56) were compared to nonusers (N = 57) in terms of neural reactivity to a Self-name (i.e., each participant's own name) stimulus, which is known to robustly activate a representation of self. Two control stimuli were additionally used: an Other-name stimulus, as a passive control condition in which no reaction was required, and a Target-name stimulus, to which participants provided a manual response and which thus constituted an active control condition. Analysis of the amplitude of the P300 ERP component evoked by the Self- or Target-names revealed no difference between the psychedelics users and nonusers. However, psychedelic users exhibited increased P300 amplitude during perception of Other-names. In addition, in comparison to nonusers, psychedelics users exhibited a smaller increase in P300 amplitude when processing the task-relevant Target-names (in relation to both Self- and Other-names). Therefore, our data suggests that regular naturalistic use of psychedelics may not be related to long-term changes in the representation of self, but it might potentially affect the allocation of attentional resources to task-relevant stimuli.

Social-touch and self-touch differ in hemodynamic response in the prefrontal cortex - a fNIRS study conducted during the coronavirus pandemic

Being touched by others (social-touch) and touching oneself (self-touch) are common nonverbal behaviors in everyday interaction. The commonalities and differences between these two types of touching behavior are of particular interest for conditions when social-touch is substantially restricted such as during the corona pandemic. Neuropsychologically, pleasant social-touch is associated with increased activation in frontal brain regions such as frontopolar, dorsolateral prefrontal (dlPFC), and orbitofrontal cortices (OFC). However, for these regions a deactivation has also been reported. Likewise, for self-touch the findings are controversial. Therefore, the aim of this study is to shed light on the controversial findings and to elucidate the relation between self-touch and social-touch. From 2021 to 2022, in a quasi-naturalistic setting, in forty-six participants brain oxygenation and deoxygenation was examined during social-touch and self-touch in frontal cortices applying functional NearInfraRed Spectroscopy (fNIRS). Social-touch compared to self-touch led to a significantly higher brain deoxygenation in the frontopolar areas and in parts of the dlPFC and OFC. In contrast, brain oxygenation in the PFC was significantly increased during self-touch compared to social-touch. The cerebral activation and deactivation pattern in a quasi-naturalistic setting indicates that self-touch cannot achieve the hedonic effects of social-touch, but it can influence internally self-regulating processes.

The blushing brain: neural substrates of cheek temperature increase in response to self-observation

Darwin proposed that blushing-the reddening of the face owing to heightened self-awareness-is 'the most human of all expressions'. Yet, relatively little is known about the underlying mechanisms of blushing. Theories diverge on whether it is a rapid, spontaneous emotional response that does not involve reflection upon the self or whether it results from higher-order socio-cognitive processes. Investigating the neural substrates of blushing can shed light on the mental processes underlying blushing and the mechanisms involved in self-awareness. To reveal neural activity associated with blushing, 16-20 year-old participants (n = 40) watched pre-recorded videos of themselves (versus other people as a control condition) singing karaoke in a magnetic resonance imaging scanner. We measured participants' cheek temperature increase-an indicator of blushing-and their brain activity. The results showed that blushing is higher when watching oneself versus others sing. Those who blushed more while watching themselves sing had, on average, higher activation in the cerebellum (lobule V) and the left paracentral lobe and exhibited more time-locked processing of the videos in early visual cortices. These findings show that blushing is associated with the activation of brain areas involved in emotional arousal, suggesting that it may occur independently of higher-order socio-cognitive processes. Our results provide new avenues for future research on self-awareness in infants and non-human animals.

On the neural networks of self and other bias and their role in emergent social interactions

Extensive research has documented the brain networks that play an integral role in bias, or the alteration and filtration of information processing in a manner that fundamentally favors an individual. The roots of bias, whether self- or other-oriented, are a complex constellation of neural and psychological processes that start at the most fundamental levels of sensory processing. From the millisecond information is received in the brain it is filtered at various levels and through various brain networks in relation to extant intrinsic activity to provide individuals with a perception of reality that complements and satisfies the conscious perceptions they have for themselves and the cultures in which they were reared. The products of these interactions, in turn, are dynamically altered by the introduction of others, be they friends or strangers who are similar or different in socially meaningful ways. While much is known about the various ways that basic biases alter specific aspects of neural function to support various forms of bias, the breadth and scope of the phenomenon remains entirely unclear. The purpose of this review is to examine the brain networks that shape (i.e., bias) the self-concept and how interactions with similar (ingroup) compared to dissimilar (outgroup) others alter these network (and subsequent interpersonal) interactions in fundamental ways. Throughout, focus is placed on an emerging understanding of the brain as a complex system, which suggests that many of these network interactions likely occur on a non-linear scale that blurs the lines between network hierarchies.

Can irrelevant self-related information in working memory be actively suppressed?

To utilize the resource of working memory efficiently, the brain actively suppresses irrelevant information to focus cognitive resources on the task at hand. However, whether task-irrelevant self-related information can be suppressed is still an open question. This study explores the inhibitory effects of various types of identity-associated information (self, friend, stranger) with an irrelevant distracting paradigm, in which participants are required to memorize the color while ignoring the shape during a memory array. In the subsequent test array, participants are asked to judge whether the color of the test item is the same as the memorized one, while the ignored shape features could also change. The results are as follows. (1) Self-associated information survived the inhibitory effect no matter whether the interstimulus interval (ISI) was short or long. (2) Stranger-associated information remained inhibitory effect in a long ISI (3000 ms). The results indicate that self-associated information can bypass the executive system and remain active in working memory processing.

Identifying the Shared and Dissociable Neural Bases between Self-Worth and Moral Ambivalence

Self-ambivalence, a prevalent phenomenon in daily life, has been increasingly substantiated by research. It refers to conflicting self-views and evaluations, primarily concerning self-worth and morality. Previous behavioral research has distinguished self-worth and moral ambivalence, but it remains unclear whether they have separable neural bases. The present study addressed this question by examining resting-state brain activity (i.e., the fractional amplitude of low-frequency fluctuations, fALFF) and connectivity (i.e., resting-state functional connectivity, RSFC) in 112 college students. The results found that self-worth ambivalence was positively related to the fALFF in the orbitofrontal cortex (OFC) and left superior parietal lobule (SPL). The RSFC strength between the SPL and precuneus/posterior cingulate cortex (PCC) was positively related to self-worth ambivalence. Moral ambivalence was positively associated with the fALFF in the left SPL (extending into the temporoparietal junction) and right SPL. The RSFC strengths between the left SPL/TPJ and OFC, as well as the RSFC strengths between the right SPL as a seed and the bilateral middle and inferior temporal gyrus, were associated with moral ambivalence. Overall, the neural bases of self-worth and moral ambivalence are associated with the SPL and OFC, involved in attentional alertness and value representation, respectively. Additionally, the neural basis of moral ambivalence is associated with the TPJ, responsible for mentalizing.

Attenuated conflict self-referential information facilitating conflict resolution

Self-referential information can reduce the congruency effect by acting as a signal to enhance cognitive control. However, it cannot be denied that self-referential information can attract and hold attention. To investigate this issue, the study used a revised Stroop task and recorded behavioral and electrophysiological data from thirty-three participants. We combined event-related potential (ERP) and multivariate pattern analysis (MVPA) to examine the neural correlates of self-referential processing and conflict processing. In the behavioral results, self-referential information reduced the congruency effect. Specifically, self-reference stimuli elicited smaller N2 amplitude than non-self-reference stimuli, indicating that self-referential information was promptly identified and reduced top-down cognitive resource consumption. Self-referential information could be reliably decoded from ERP signals in the early-to-mid stage. Moreover, self-reference conditions exhibited earlier congruency decoding than non-self-reference conditions, facilitating conflict monitoring. In the late stage, under the incongruent condition, self-reference stimuli elicited smaller sustained potential amplitude than non-self-reference stimuli, indicating that cognitive control in the self-reference condition required fewer cognitive resources for conflict resolution. Together, these findings revealed that self-referential information was identified and facilitated conflict monitoring, leading to more effective conflict resolution.

Causal Roles of Ventral and Dorsal Neural Systems for Automatic and Control Self-Reference Processing: A Function Lesion Mapping Study

Background: Humans perceive and interpret the world through the lens of self-reference processes, typically facilitating enhanced performance for the task at hand. However, this research has predominantly emphasized the automatic facet of self-reference processing, overlooking how it interacts with control processes affecting everyday situations. Methods: We investigated this relationship between automatic and control self-reference processing in neuropsychological patients performing self-face perception tasks and the Birmingham frontal task measuring executive functions. Results: Principal component analysis across tasks revealed two components: one loaded on familiarity/orientation judgments reflecting automatic self-reference processing, and the other linked to the cross task and executive function indicating control processing requirements. Voxel-based morphometry and track-wise lesion-mapping analyses showed that impairments in automatic self-reference were associated with reduced grey matter in the ventromedial prefrontal cortex and right inferior temporal gyrus, and white matter damage in the right inferior fronto-occipital fasciculus. Deficits in executive control were linked to reduced grey matter in the bilateral inferior parietal lobule and left anterior insula, and white matter disconnections in the left superior longitudinal fasciculus and arcuate fasciculus. Conclusions: The causal evidence suggests that automatic and control facets of self-reference processes are subserved by distinct yet integrated ventral prefrontal-temporal and dorsal frontal-parietal networks, respectively.

Neurophysiological Oscillatory Mechanisms Underlying the Effect of Mirror Visual Feedback-Induced Illusion of Hand Movements on Nociception and Cortical Activation

Mirror Visual Feedback (MVF)-induced illusion of hand movements produces beneficial effects in patients with chronic pain. However, neurophysiological mechanisms underlying these effects are poorly known. In this preliminary study, we test the novel hypothesis that such an MVF-induced movement illusion may exert its effects by changing the activity in midline cortical areas associated with pain processing. Electrical stimuli with individually fixed intensity were applied to the left hand of healthy adults to produce painful and non-painful sensations during unilateral right-hand movements with such an MVF illusion and right and bilateral hand movements without MVF. During these events, electroencephalographic (EEG) activity was recorded from 64 scalp electrodes. Event-related desynchronization (ERD) of EEG alpha rhythms (8-12 Hz) indexed the neurophysiological oscillatory mechanisms inducing cortical activation. Compared to the painful sensations, the non-painful sensations were specifically characterized by (1) lower alpha ERD estimated in the cortical midline, angular gyrus, and lateral parietal regions during the experimental condition with MVF and (2) higher alpha ERD estimated in the lateral prefrontal and parietal regions during the control conditions without MVF. These preliminary results suggest that the MVF-induced movement illusion may affect nociception and neurophysiological oscillatory mechanisms, reducing the activation in cortical limbic and default mode regions.

Normativity vs. uniqueness: effects of social relationship strength on neural representations of others

Understanding others involves inferring traits and intentions, a process complicated by our reliance on stereotypes and generalized information when we lack personal information. Yet, as relationships are formed, we shift toward nuanced and individualized perceptions of others. This study addresses how relationship strength influences the creation of unique or normative representations of others in key regions known to be involved in social cognition. Employing a round-robin interpersonal perception paradigm (N = 111, 20 groups of five to six people), we used functional magnetic resonance imaging to examine whether the strength of social relationships modulated the degree to which multivoxel patterns of activity that represented a specific other were similar to a normative average of all others in the study. Behaviorally, stronger social relationships were associated with more normative trait endorsements. Neural findings reveal that closer relationships lead to more unique representations in the medial prefrontal cortex and anterior insula, areas associated with mentalizing and person perception. Conversely, more generalized representations emerge in posterior regions like the posterior cingulate cortex, indicating a complex interplay between individuated and generalized processing of social information in the brain. These findings suggest that cortical regions typically associated with social cognition may compute different kinds of information when representing the distinctiveness of others.

A Dynamic Multi-Scale Convolution Model for Face Recognition Using Event-Related Potentials

With the development of data mining technology, the analysis of event-related potential (ERP) data has evolved from statistical analysis of time-domain features to data-driven techniques based on supervised and unsupervised learning. However, there are still many challenges in understanding the relationship between ERP components and the representation of familiar and unfamiliar faces. To address this, this paper proposes a model based on Dynamic Multi-Scale Convolution for group recognition of familiar and unfamiliar faces. This approach uses generated weight masks for cross-subject familiar/unfamiliar face recognition using a multi-scale model. The model employs a variable-length filter generator to dynamically determine the optimal filter length for time-series samples, thereby capturing features at different time scales. Comparative experiments are conducted to evaluate the model's performance against SOTA models. The results demonstrate that our model achieves impressive outcomes, with a balanced accuracy rate of 93.20% and an F1 score of 88.54%, outperforming the methods used for comparison. The ERP data extracted from different time regions in the model can also provide data-driven technical support for research based on the representation of different ERP components.

The functional connectivity between right insula and anterior cingulate cortex underlying the association between future self-continuity and delay discounting

Delay discounting refers to the tendency of individuals to devalue future rewards as the delay in their receipt increases over time. Previous studies have indicated that future self-continuity correlates with delay discounting rates. However, the neural basis underlying the relationship between future self-continuity and delay discounting is not clear. To address this question, we used voxel-based morphometry and resting-state functional connectivity analyses to investigate the neural basis underlying the association between future self-continuity and delay discounting. Behavioral result showed that future self-continuity was positively associated with delay discounting. Voxel-based morphometry analysis result indicated that gray matter volume in the right dorsal anterior insula was positively correlated with future self-continuity. Resting-state functional connectivity analysis found that functional connectivity between the right dorsal anterior insula and anterior cingulate cortex was positively associated with future self-continuity. Mediation analysis showed that the right dorsal anterior insula-right anterior cingulate cortex functional connectivity partially mediated the relationship between future self-continuity and delay discounting. These results suggested that right dorsal anterior insula-right anterior cingulate cortex functional connectivity could be the neural basis underlying the association between future self-continuity and delay discounting. In summary, the study provided novel insights into how future self-continuity affected delay discounting and offers new explanations from a neural perspective.

Abnormal intrinsic functional hubs and connectivity in patients with post-stroke depression

OBJECTIVE

The present study aimed to investigate the specific alterations of brain networks in patients with post-stroke depression (PSD), and further assist in elucidating the brain mechanisms underlying the PSD which would provide supporting evidence for early diagnosis and interventions for the disease.

METHODS

Resting-state functional magnetic resonace imaging data were acquired from 82 nondepressed stroke patients (Stroke), 39 PSD patients, and 74 healthy controls (HC). Voxel-wise degree centrality (DC) conjoined with seed-based functional connectivity (FC) analyses were performed to investigate the PSD-related connectivity alterations. The relationship between these alterations and depression severity was further examined in PSD patients.

RESULTS

Relative to both Stroke and HC groups, (1) PSD showed increased centrality in regions within the default mode network (DMN), including contralesional angular gyrus (ANG), posterior cingulate cortex (PCC), and hippocampus (HIP). DC values in contralesional ANG positively correlated with the Patient Health Questionnaire-9 (PHQ-9) scores in PSD group. (2) PSD exhibited increased connectivity between these three seeds showing altered DC and regions within the DMN: bilateral medial prefrontal cortex and middle temporal gyrus and ipsilesional superior parietal gyrus, and regions outside the DMN: bilateral calcarine, ipsilesional inferior occipital gyrus and contralesional lingual gyrus, while decreased connectivity between contralesional ANG and contralesional supramarginal gyrus. Moreover, these FC alterations could predict PHQ-9 scores in PSD group.

INTERPRETATION

These findings highlight that PSD was related with increased functional connectivity strength in some areas within the DMN, which might be attribute to the specific alterations of connectivity between within DMN and outside DMN regions in PSD.

Global neural self-disturbance in schizophrenia: A systematic fMRI review

There is a general consensus that schizophrenia (SZ) is characterized by major changes in the sense of self. Phenomenological studies suggest that these changes in the sense of self stem from a basic disturbance, hence the term 'basic self-disturbance'. While imaging studies demonstrate changes in various regions during self-focused tasks, the exact neural correlates of such basic self-disturbances remain unclear. If the self-disturbance is indeed basic and thereby underlies all other symptoms, one would expect it to be related to more global rather than local changes in the brain. Testing this hypothesis, we conducted a systematic review of fMRI studies on self in SZ. Our main findings are 1. Abnormal activity related to the self can be observed in a variety of different regions ranging from higher-order transmodal to lower-order unimodal regions, 2. These findings hold true across different tasks including self-reflection, self-referentiality, and self-agency, and 3. The global neural abnormalities related to the self in SZ correspond to all layers of the self, predominantly the mental and exteroceptive self. Such global neural disturbance of self converges well with the basic self-disturbance as described in phenomenology.

Neural correlates of chocolate brand preference: A functional MRI study

BACKGROUND AND PURPOSE

Preferences can be developed for, or against, specific brands and services. Using two functional magnetic resonance imaging (fMRI) experiments, this study investigated two dissociable aspects of reward processing, craving and liking, in chocolate lovers. The goal was to further delineate the neural basis supporting branding effects using familiar chocolate (FC) and unfamiliar chocolate (UC) brand images.

METHODS

In the first experiment, subjects rated their subjective craving and liking on a scale of 1-5 (weak-strong) for each FC and UC image. In the second experiment, they performed a choice task between FC and UC images.

RESULTS

Both the craving and liking ratings were significantly greater for FC and were differentially correlated with choice behavior. Craving ratings predicted greater preference for UC, and liking ratings predicted greater preference for FC. A contrast of neural activity for UC versus FC choice trials revealed significantly greater activation for UC choices in the bilateral inferior frontal gyrus and right caudate head. Response times for the FC images were faster than UC images; fMRI activity in the ventromedial prefrontal cortex was significantly correlated with response times during FC trials, but not UC trials. These correlations were significantly different from each other at the group level.

CONCLUSIONS

The choices for branded chocolate products are driven by higher subjective reward ratings and lower neural processing demands.

Prefrontal cortex neurons encode ambient light intensity differentially across regions and layers

While light can affect emotional and cognitive processes of the medial prefrontal cortex (mPFC), no light-encoding was hitherto identified in this region. Here, extracellular recordings in awake mice revealed that over half of studied mPFC neurons showed photosensitivity, that was diminished by inhibition of intrinsically photosensitive retinal ganglion cells (ipRGCs), or of the upstream thalamic perihabenular nucleus (PHb). In 15% of mPFC photosensitive neurons, firing rate changed monotonically along light-intensity steps and gradients. These light-intensity-encoding neurons comprised four types, two enhancing and two suppressing their firing rate with increased light intensity. Similar types were identified in the PHb, where they exhibited shorter latency and increased sensitivity. Light suppressed prelimbic activity but boosted infralimbic activity, mirroring the regions' contrasting roles in fear-conditioning, drug-seeking, and anxiety. We posit that prefrontal photosensitivity represents a substrate of light-susceptible, mPFC-mediated functions, which could be ultimately studied as a therapeutical target in psychiatric and addiction disorders.

Resting-state networks and anosognosia in Alzheimer's disease

Background

Recent evidence suggests that anosognosia or unawareness of cognitive impairment in Alzheimer's Disease (AD) may be explained by a disconnection between brain regions involved in accessing and monitoring information regarding self and others. It has been demonstrated that AD patients with anosognosia have reduced connectivity within the default mode network (DMN) and that anosognosia in people with prodromal AD is positively associated with bilateral anterior cingulate cortex (ACC), suggesting a possible role of this region in mechanisms of awareness in the early phase of disease. We hypothesized that anosognosia in AD is associated with an imbalance between the activity of large-scale resting-state functional magnetic resonance imaging (fMRI) networks, in particular the DMN, the salience network (SN), and the frontoparietal network (FPN).

Methods

Sixty patients with MCI and AD dementia underwent fMRI and neuropsychological assessment including the Anosognosia Questionnaire Dementia (AQ-D), a measure of anosognosia based on a discrepancy score between patient's and carer's judgments. After having applied Independent Component Analysis (ICA) to resting fMRI data we performed: (i) correlations between the AQ-D score and functional connectivity in the DMN, SN, and FPN, and (ii) comparisons between aware and unaware patients of the DMN, SN, and FPN functional connectivity.

Results

We found that anosognosia was associated with (i) weak functional connectivity within the DMN, in posterior and middle cingulate cortex particularly, (ii) strong functional connectivity within the SN in ACC, and between the SN and basal ganglia, and (iii) a heterogenous effect concerning the functional connectivity of the FPN, with a weak connectivity between the FPN and PCC, and a strong connectivity between the FPN and ACC. The observed effects were controlled for differences in severity of cognitive impairment and age.

Conclusion

Anosognosia in the AD continuum is associated with a dysregulation of the functional connectivity of three large-scale networks, namely the DMN, SN, and FPN.

Forgetting ourselves in flow: an active inference account of flow states and how we experience ourselves within them

Flow has been described as a state of optimal performance, experienced universally across a broad range of domains: from art to athletics, gaming to writing. However, its phenomenal characteristics can, at first glance, be puzzling. Firstly, individuals in flow supposedly report a loss of self-awareness, even though they perform in a manner which seems to evince their agency and skill. Secondly, flow states are felt to be effortless, despite the prerequisite complexity of the tasks that engender them. In this paper, we unpick these features of flow, as well as others, through the active inference framework, which posits that action and perception are forms of active Bayesian inference directed at sustained self-organisation; i.e., the minimisation of variational free energy. We propose that the phenomenology of flow is rooted in the deployment of high precision weight over (i) the expected sensory consequences of action and (ii) beliefs about how action will sequentially unfold. This computational mechanism thus draws the embodied cognitive system to minimise the ensuing (i.e., expected) free energy through the exploitation of the pragmatic affordances at hand. Furthermore, given the challenging dynamics the flow-inducing situation presents, attention must be wholly focussed on the unfolding task whilst counterfactual planning is restricted, leading to the attested loss of the sense of self-as-object. This involves the inhibition of both the sense of self as a temporally extended object and higher-order, meta-cognitive forms of self-conceptualisation. Nevertheless, we stress that self-awareness is not entirely lost in flow. Rather, it is pre-reflective and bodily. Our approach to bodily-action-centred phenomenology can be applied to similar facets of seemingly agentive experience beyond canonical flow states, providing insights into the mechanisms of so-called selfless experiences, embodied expertise and wellbeing.

Behavioral dishonesty in multiscenes: Associations with trait honesty and neural patterns during (dis)honesty video-watching

Cross-situational inconsistency is common in the expression of honesty traits; yet, there is insufficient emphasis on behavioral dishonesty across multiple contexts. The current study aimed to investigate behavioral dishonesty in various contexts and reveal the associations between trait honesty, behavioral dishonesty, and neural patterns of observing others behave honestly or dishonestly in videos (abbr.: (dis)honesty video-watching). First, the results revealed limitations in using trait honesty to reflect variations in dishonest behaviors and predict behavioral dishonesty. The finding highlights the importance of considering neural patterns in understanding and predicting dishonest behaviors. Second, by comparing the predictive performance of seven types of data across three neural networks, the results showed that functional connectivity in the hypothesis-driven network during (dis)honesty video-watching provided the highest predictive power in predicting multitask behavioral dishonesty. Last, by applying the feature elimination method, the midline self-referential regions (medial prefrontal cortex, posterior cingulate cortex, and anterior cingulate cortex), anterior insula, and striatum were identified as the most informative brain regions in predicting behavioral dishonesty. In summary, the study offered insights into individual differences in deception and the intricate connections among trait honesty, behavioral dishonesty, and neural patterns during (dis)honesty video-watching.

Examining the influence of self-referential thinking on aberrant salience and jumping to conclusions bias in individuals with schizophrenia-spectrum disorders

BACKGROUND AND OBJECTIVES

Cognitive processes such as aberrant salience and the jumping to conclusions (JTC) bias are implicated in the development of delusions. Self-referential thinking is implicated in this process; however, it is unknown how it may interact with aberrant salience and JTC bias in individuals with schizophrenia-spectrum disorders (SSDs). This study examined associations of self-referential thinking with aberrant salience, JTC bias, and delusion severity, and whether self-referential stimuli led to an increase in aberrant salience and JTC bias in SSDs (n = 20) relative to psychiatrically healthy controls (n = 20).

METHODS

To assess aberrant salience and JTC bias, participants were asked to complete both self-referential and neutral versions of the Salience Attribution Test (SAT) and the Beads Task, as well as self-report measures of aberrant salience and JTC bias.

RESULTS

Self-referential task condition interacted with clinical group to predict JTC beads task scores, such that participants with SSDs exhibited greater levels of JTC bias than psychiatrically healthy controls during the neutral task condition, when controlling for levels of motivation, cognitive insight, and functioning. Self-referential thinking was significantly associated with aberrant salience, JTC bias, and delusion severity.

LIMITATIONS

This experiment examined trait-level relationships between variables, so does not provide information about state-level interrelationships and would benefit from replication using more dynamic methods such as ecological momentary assessment.

CONCLUSIONS

These findings highlight the interrelationships between self-referential thinking, JTC bias, aberrant salience, and delusion severity, in individuals with SSDs, and support the interactive role of self-referential thinking in predicting JTC bias.

ERP correlates of self-referential processing moderate the association between pubertal status and disordered eating in preadolescence

Preadolescence is a critical period for the onset of puberty and eating-related psychopathology. More advanced pubertal status is associated with elevated eating pathology. However, it was unclear whether this association was moderated by self-referential processing, an important, modifiable cognitive risk for various forms of psychopathology, including eating problems. Further, no study has examined the neural correlates of self-referential processing in relation to eating pathology. To address these gaps, we examined how the association between pubertal status and disordered eating was moderated by self-referential processing in a community sample of 115 nine-to-12-year-old preadolescents (66 girls; mean age/SD = 10.98/1.18 years; 87.5% White). Youths reported their pubertal status and disordered eating behaviors and completed an ERP version of the Self-Referent Encoding Task (SRET) to assess self-referential processing. A Principal Component Analysis of the ERP data identified an anterior late positive potential (LPP) in both the positive and negative SRET conditions. The LPP in the positive condition moderated the positive association between pubertal status and disordered eating behaviors, such that this association was significant for youths with a smaller LPP toward positive self-referential cues, but non-significant for those showing a larger LPP toward positive self-referential cues. These results suggest that a deeper processing of positive self-referential information, indicated by a potentiated LPP, may weaken the negative impact of pubertal status on disordered eating. Our findings also suggest that enhancing positive self-referential processing may be a useful tool in preventing the development of eating pathology in preadolescents, especially for those with more advanced pubertal status.

The neural representation of self, close, and famous others: An electrophysiological investigation on the social brain

It is well established that the Self has a unique representation in the social brain, as evident from the Self-Referential Effect (SRE). However, the timing and neural mechanisms underlying the representation of individuals with varying degrees of closeness and emotional relevance to the Self remain unclear. Twenty-two participants read 260 personality traits and decided whether they described themselves, a close friend, or an admired celebrity. A strong Self-Referential Effect (SRE) was found at behavioral, ERP, and neuroimaging levels. Three anterior ERP components were identified as sensitive to social information: a P200 (250-350 ms) responding to famous others' traits, a P600 (500-700 ms) responding to self-trait processing, and a late positivity (800-950 ms) responding to self-trait processing and close traits. Source reconstructions revealed partially overlapping but distinct neural sources for each individual. The right precuneus (bodily self) and inferior frontal areas (inner voice) were active only during self-processing, while the right medial prefrontal cortex (BA10) was consistently active across tasks, showing a robust SRE. These findings provide insights into the neural mechanisms underlying the representation of the Self in social contexts.