Functional neuroanatomy of interoceptive processing in children and adolescents: a pilot study

Heartbeat-related spectral perturbation of electroencephalogram reflects dynamic interoceptive attention states in the trial-by-trial classification analysis

Attending to heartbeats for interoceptive awareness initiates distinct electrophysiological responses synchronized with the R-peaks of an electrocardiogram (ECG), such as the heartbeat-evoked potential (HEP). Beyond HEP, this study proposes heartbeat-related spectral perturbation (HRSP), a time-frequency map of the R-peak locked electroencephalogram (EEG), and explores its characteristics in identifying interoceptive attention states using a classification approach. HRSPs of EEG brain components specified by independent component analysis (ICA) were used for the offline and online classification of interoceptive states. A convolutional neural network (CNN) designed specifically for HRSP was applied to publicly available data from a binary-state experiment (attending to self-heartbeats and white noise) and data from our four-state classification experiment (attending to self-heartbeats, white noise, time passage, and toe) with diverse input feature conditions of HRSP. From the dynamic state perspective, we evaluated the primary frequency bands of HRSP and the minimal number of averaging epochs required to reflect changing interoceptive attention states without compromising accuracy. We also assessed the utility of group ICA and models for classifying HRSP in new participants. The CNN for trial-by-trial HRSP with actual R-peaks demonstrated significantly higher classification accuracy than HRSP with sham, i.e., randomly positioned, R-peaks. Gradient-weighted class activation mapping highlighted the prominent role of theta and alpha bands between 200-600 ms post-R-peak-features absent in classifications using sham HRSPs. Online classification benefits from employing a group ICA and classification model, ensuring reliable accuracy without individual EEG precollection. These results suggest HRSP's potential to reflect interoceptive attention states, proposing transformative implications for clinical applications.

Should Adolescents Listen to Their Hearts? A Closer Look at the Associations Between Interoception, Emotional Awareness and Emotion Regulation in Adolescents

The aim of the current study was to replicate findings from prior work among adults showing that individuals with better interoceptive skills have more emotional awareness, and show better emotion regulation abilities, in a sample of adolescents and by relying on instructions that reduce the contamination of known confound variables. A total of 102 Belgian adolescents (Mage = 14.10 years, SDage = .63; 50 males) completed self-report questionnaires of emotional processes (FEEL-KJ and DERS) and the modified heartbeat counting task. From this task, interoceptive accuracy, interoceptive sensibility (confidence ratings), and interoceptive awareness scores (within-person correlations) were derived per participant. Results revealed no associations between the three dimensions of interoception and adolescents' levels of emotional awareness, adaptive, and maladaptive emotion regulation. The lack of associations which contrast some prior work with adults may be due to developmental differences. However, these might also support the low validity of the heartbeat counting task, or could be attributed to the measurement of the emotion measures (i.e., self-report). Future studies should, nevertheless, also test whether these non-significant results can be explained by the developmental differences in adolescents. Longitudinal research is needed to capture interoceptive changes during adolescence, as well as to replicate the current findings using rigorous multimethod approaches that increase the validity of interoception measurement.

Interoceptive brain network mechanisms of mindfulness-based training in healthy adolescents

Introduction

This study evaluated changes in the white matter of the brain and psychological health variables, resulting from a neuroscience-based mindfulness intervention, the Training for Awareness, Resilience, and Action (TARA), in a population of healthy adolescents.

Methods

A total of 100 healthy adolescents (57 female, age ranges 14-18 years) were randomized into the 12-week TARA intervention or a waitlist-control group. All participants were imaged with diffusion MRI to quantify white matter connectivity between brain regions. Imaging occurred at baseline/randomization and after 12 weeks of baseline (pre- and post-intervention in the TARA group). We hypothesized that structural connectivity in the striatum and interoceptive networks would increase following the TARA intervention, and that, this increased connectivity would relate to psychological health metrics from the Strengths and Difficulties Questionnaire (SDQ) and the Insomnia Severity Index (ISI). The TARA intervention and all assessments, except for the MRIs, were fully remotely delivered using secure telehealth platforms and online electronic data capture systems.

Results

The TARA intervention showed high consistency, tolerability, safety, recruitment, fidelity, adherence, and retention. After 12 weeks, the TARA group, but not controls, also demonstrated significantly improved sleep quality (p = 0.02), and changes in the right putamen node strength were related to this improved sleep quality (r = -0.42, p = 0.006). Similarly, the TARA group, but not controls, had significantly increased right insula node strength related to improved emotional well-being (r = -0.31, p = 0.04). Finally, we used the network-based statistics to identify a white matter interoception network that strengthened following TARA (p = 0.009).

Discussion

These results suggest that the TARA mindfulness-based intervention in healthy adolescents is feasible and safe, and it may act to increase structural connectivity strength in interoceptive brain regions. Furthermore, these white matter changes are associated with improved adolescent sleep quality and emotional well-being. Our results suggest that TARA could be a promising fully remotely delivered intervention for improving psychological well-being in adolescents. As our findings suggest that TARA affects brain regions in healthy adolescents, which are also known to be altered during depression in adolescents, future studies will examine the effects of TARA on depressed adolescents.

Clinical trial registration

https://clinicaltrials.gov/study/NCT04254796.

Intuitive Eating Scale-2-EA: Psychometric properties and factor structure of the adapted IES-2 for early adolescents

PURPOSE

Intuitive Eating (IE) is an approach to eating characterised by attunement to intrinsic cues, and using those cues to guide behaviours related to food and eating. Tylka and Kroon Van Diest's (2008) Intuitive Eating Scale (IES-2) is well-validated in adults, but not yet among early adolescents. The current study was designed to adapt and validate a version suited for use in early adolescence (IES-2-EA).

METHODS

Data collected from two independent samples of adolescents aged 11 to 13 (N = 471) were structurally examined using exploratory factor analysis (EFA), with a subsequent confirmatory factor analysis (CFA) to confirm hypothesised model fit. Relationships between scores on the IES-2-EA and validated measures of actual-ideal body size discrepancy, body appreciation, interoceptive awareness, and psychological distress were also examined.

RESULTS

The adapted 17-item IES-2-EA had a three-factor structure with several key differences from the original version developed for adults. Moderate-to-strong correlations were found between scores on the IES-2-EA, body appreciation, interoceptive awareness, actual-ideal body size discrepancy, and psychological distress in the first sample of adolescents (n = 245). Secondary CFA showed good model fit in the second sample of adolescents (n = 226).

CONCLUSION

The IES-2-EA is well-suited to measure intuitive eating behaviour among early adolescents. The 17 items reflect a three-component structure similar to that seen in adults completing the IES-2. These early data suggest the adapted IES-2-EA has evidence of reliability and validity; it may be an effective measure for research and clinical use.

A pediatric near-infrared spectroscopy brain-computer interface based on the detection of emotional valence

Brain-computer interfaces (BCIs) are being investigated as an access pathway to communication for individuals with physical disabilities, as the technology obviates the need for voluntary motor control. However, to date, minimal research has investigated the use of BCIs for children. Traditional BCI communication paradigms may be suboptimal given that children with physical disabilities may face delays in cognitive development and acquisition of literacy skills. Instead, in this study we explored emotional state as an alternative access pathway to communication. We developed a pediatric BCI to identify positive and negative emotional states from changes in hemodynamic activity of the prefrontal cortex (PFC). To train and test the BCI, 10 neurotypical children aged 8–14 underwent a series of emotion-induction trials over four experimental sessions (one offline, three online) while their brain activity was measured with functional near-infrared spectroscopy (fNIRS). Visual neurofeedback was used to assist participants in regulating their emotional states and modulating their hemodynamic activity in response to the affective stimuli. Child-specific linear discriminant classifiers were trained on cumulatively available data from previous sessions and adaptively updated throughout each session. Average online valence classification exceeded chance across participants by the last two online sessions (with 7 and 8 of the 10 participants performing better than chance, respectively, in Sessions 3 and 4). There was a small significant positive correlation with online BCI performance and age, suggesting older participants were more successful at regulating their emotional state and/or brain activity. Variability was seen across participants in regards to BCI performance, hemodynamic response, and discriminatory features and channels. Retrospective offline analyses yielded accuracies comparable to those reported in adult affective BCI studies using fNIRS. Affective fNIRS-BCIs appear to be feasible for school-aged children, but to further gauge the practical potential of this type of BCI, replication with more training sessions, larger sample sizes, and end-users with disabilities is necessary.

Action Understanding Promoted by Interoception in Children: A Developmental Model

Action understanding of children develops from simple associative learning to mentalizing. With the rise of embodied cognition, the role of interoception in action observation and action understanding has received more attention. From a developmental perspective, this study proposes a novel developmental model that explores how interoception promotes action understanding of children across ages. In early infancy, most actions observed in infants come from interactions with their caregivers. Babies learn about action effects through automatic interoceptive processing and interoceptive feedback. Interoception in early infancy is not fully developed, such as the not fully developed gastrointestinal tract and intestinal nervous system. Therefore, in early infancy, action understanding is based on low-level and original interoceptive information. At this stage, after observing the actions of others, infants can create mental representations or even imitate actions without external visual feedback, which requires interoception to provide internal reference information. By early childhood, children begin to infer action intentions of other people by integrating various types of information to reach the mentalizing level. Interoception processing requires the integration of multiple internal signals, which promotes the information integration ability of children. Interoception also provides inner information for reasoning about action intention. This review also discussed the neural mechanisms of interoception and possible ways by which it could promote action understanding of children. In early infancy, the central autonomic neural network (CAN) automatically processes and responds to the actions of caregivers on infants, providing interoceptive information for action understanding of infants. In infancy, the growth of the somatomotor system provides important internal reference information for observing and imitating the actions of infants. In early childhood, the development of interoception of children facilitates the integration of internal and external information, which promotes the mentalization of action understanding of children. According to the proposed developmental model of action understanding of children promoted by interoception, there are multilevel and stage-dependent characteristics that impact the role of interoception in action understanding of children.

Atypical interoception as a common risk factor for psychopathology: A review

The inadequacy of a categorial approach to mental health diagnosis is now well-recognised, with many authors, diagnostic manuals and funding bodies advocating a dimensional, trans-diagnostic approach to mental health research. Variance in interoception, the ability to perceive one's internal bodily state, is reported across diagnostic boundaries, and is associated with atypical functioning across symptom categories. Drawing on behavioural and neuroscientific evidence, we outline current research on the contribution of interoception to numerous cognitive and affective abilities (in both typical and clinical populations), and describe the interoceptive atypicalities seen in a range of psychiatric conditions. We discuss the role that interoception may play in the development and maintenance of psychopathology, as well as the ways in which interoception may differ across clinical presentations. A number of important areas for further research on the role of interoception in psychopathology are highlighted.

An Embodied Cognition Perspective on the Role of Interoception in the Development of the Minimal Self

Interoception is an often neglected but crucial aspect of the human minimal self. In this perspective, we extend the embodiment account of interoceptive inference to explain the development of the minimal self in humans. To do so, we first provide a comparative overview of the central accounts addressing the link between interoception and the minimal self. Grounding our arguments on the embodiment framework, we propose a bidirectional relationship between motor and interoceptive states, which jointly contribute to the development of the minimal self. We present empirical findings on interoception in development and discuss the role of interoception in the development of the minimal self. Moreover, we make theoretical predictions that can be tested in future experiments. Our goal is to provide a comprehensive view on the mechanisms underlying the minimal self by explaining the role of interoception in the development of the minimal self.

Exploring the Multidimensional Assessment of Interoceptive Awareness in youth aged 7-17 years

OBJECTIVE

This study aimed to adapt the Multidimensional Assessment of Interoceptive Awareness (MAIA) questionnaire for younger respondents.

METHOD

The language of the MAIA was revised and children aged 7-10 years (n = 212) and adolescents aged 11-17 years (n = 217) completed the questionnaire.

RESULTS

The original eight-factor model was tested for fit using confirmatory factor analysis. The model had an acceptable fit in the total sample and younger subsample and overall fit in the older subsample was adequate following modification. Internal consistency was good, except for the Noticing, Not-Distracting and Not-Worrying scales. Results also demonstrated a negative linear relationship between the trusting scale and age, suggesting that youths may lose trust in their body as they age.

CONCLUSION

The adapted MAIA can be used with a younger population and, depending on the research question, individual MAIA scales may be selected. The survey is available at https://osher.ucsf.edu/maia.

A multidimensional and multi-feature framework for cardiac interoception

Interoception (the sensing of inner-body signals) is a multi-faceted construct with major relevance for basic and clinical neuroscience research. However, the neurocognitive signatures of this domain (cutting across behavioral, electrophysiological, and fMRI connectivity levels) are rarely reported in convergent or systematic fashion. Additionally, various controversies in the field might reflect the caveats of standard interoceptive accuracy (IA) indexes, mainly based on heartbeat detection (HBD) tasks. Here we profit from a novel IA index (md) to provide a convergent multidimensional and multi-feature approach to cardiac interoception. We found that outcomes from our IA-md index are associated with -and predicted by- canonical markers of interoception, including the hd-EEG-derived heart-evoked potential (HEP), fMRI functional connectivity within interoceptive hubs (insular, somatosensory, and frontal networks), and socio-emotional skills. Importantly, these associations proved more robust than those involving current IA indexes. Furthermore, this pattern of results persisted when taking into consideration confounding variables (gender, age, years of education, and executive functioning). This work has relevant theoretical and clinical implications concerning the characterization of cardiac interoception and its assessment in heterogeneous samples, such as those composed of neuropsychiatric patients.