Interoception in preschoolers: New insights into its assessment and relations to emotion regulation and stress

in Biological Psychology (2021), 165(1), 108166

Interoception may play an important role for emotion regulation and stress, thereby affecting mental health in children and adults. Yet, little is known on interoception in preschool children. Therefore ... [more ▼]

Interoception may play an important role for emotion regulation and stress, thereby affecting mental health in children and adults. Yet, little is known on interoception in preschool children. Therefore, we investigated interoceptive accuracy using the adapted Jumping Jack Paradigm (JJP) and its relationship with emotion regulation and stress. In Study I, 40 preschoolers completed the JJP and an emotion regulation task, demonstrating a positive relationship between interoceptive accuracy and emotion regulation at trend level (R² = 0.231, p = .023; β = .278, p = .073). In Study II, 31 preschoolers completed the adapted JJP before and after an acute laboratory stress test. Higher total cortisol output following acute stress induction were associated with reduced interoceptive accuracy (r = -0.670, p = .017). Extending earlier findings in adults and school-children, the relationship of interoceptive accuracy with emotion regulation and stress highlights the importance to investigate interoception in early childhood. [less ▲]

Distinctive body perception mechanisms in high versus low symptom reporters: a neurophysiological model for medically-unexplained symptoms

in Journal of Psychosomatic Research (2020), 137(1), 110223

OBJECTIVE: The neurophysiological processes involved in the generation of medicallyunexplained symptoms (MUS) remain unclear. This study tested three assumptions of the perception-filter model ... [more ▼]

OBJECTIVE: The neurophysiological processes involved in the generation of medicallyunexplained symptoms (MUS) remain unclear. This study tested three assumptions of the perception-filter model contributing to MUS: (I.) increased bodily signal strength (II.) decreased filter function, (III.) increased perception. METHODS: In this cross-sectional, observational study, trait MUS was assessed by a webbased survey (N=486). The upper and lower decile were identified as extreme groups of high (HSR; n=29; 26 women; Mage=26.0 years) and low symptom reporters (LSR; n=29; 21 women; Mage=28.4 years). Mean heart rate (HR) and heart rate variability (HRV), and cortisol awakening response (CAR) were assessed as indicators of bodily signal strength (I.). Heartbeat-evoked potentials (HEPs) were assessed during rest and a heartbeat perception task. HEPs reflect attentional resources allocated towards heartbeats and served as index of filter function (II.). Interoceptive accuracy (IAc) in heartbeat perception was assessed as an indicator of perception (III.). RESULTS: HSR showed higher HR and lower HRV (RMSSD) than LSR (I.), but no differences in CAR. HSR exhibited a stronger increase of HEPs when attention was focused on heartbeats than LSR (II.); there were no group differences in IAc (III.). CONCLUSIONS: The perception-filter model was partially confirmed in that HSR showed altered bodily signals suggesting higher sympathetic activity (I.); higher HEP increases indicated increased filter function for bodily signals (II.). As more attentional resources are mobilized to process heartbeats, but perception accuracy remains unchanged (III.), this overflow could be responsible for detecting minor bodily changes associated with MUS. [less ▲]

Health benefits of walking in nature: a randomized controlled study under conditions of real-life stress.

in Environment and Behavior (2020), 52(3), 248-274

We investigated the effects of recreational exposure to the natural environment on mood and psychophysiological responses to stress. We hypothesized that walking in nature has restorative effects over and ... [more ▼]

We investigated the effects of recreational exposure to the natural environment on mood and psychophysiological responses to stress. We hypothesized that walking in nature has restorative effects over and above the effects of exposure to nature scenes (viewing-nature-on-TV) or physical exercise alone (walking-on-a-treadmill-in-a-gym) and that these effects are greater when participants were expected to be more stressed. Healthy university students (N=90) were randomly allocated to 1 of 3 conditions and tested during an exam-free period and again during their exam time. Mood and psychophysiological responses were assessed before and after the interventions, and again after a laboratory stressor. All interventions had restorative effects on cortisol levels (p < .001), yet walking in nature resulted in lower cortisol levels than did nature viewing (p < .05) during the exam period. Walking in nature improved mood more than watching nature scenes (p < .001) or physical exercise alone (p < .05). [less ▲]

Interoception, stress and physical symptoms in stress-associated diseases

in European Journal of Health Psychology (2020), 27(1), 132-153

The brain and peripheral bodily organs continuously exchange information. Exemplary, interoception refers to the processing and perception of ascending information from the body to the brain. Stress ... [more ▼]

The brain and peripheral bodily organs continuously exchange information. Exemplary, interoception refers to the processing and perception of ascending information from the body to the brain. Stress responses involve a neurobehavioral cascade, which includes the activation of peripheral organs via neural and endocrine pathways and can thus be seen as an example for descending information on the brain-body axis. Hence, the interaction of interoception and stress represents bi-directional communication on the brain-body axis. The main hypothesis underlying this review is that the dysregulation of brain-body communication represents an important mechanism for the generation of physical symptoms in stress-related disorders. The aims of this review are, therefore, (1.) to summarize current knowledge on acute stress effects on different stages of interoceptive signal processing, (2.) to discuss possible patterns of abnormal brainbody communication (i.e., alterations in interoception and physiological stress axes activation) in mental disorders and chronic physical conditions, and (3.) to consider possible approaches to modify interoception. Due to the regulatory feedback loops underlying brain-body communication, the modification of interoceptive processes (ascending signals) may, in turn, affect physiological stress axes activity (descending signals), and, ultimately, also physical symptoms. [less ▲]

Heart and brain: cortical representation of cardiac signals is disturbed in borderline personality disorder, but unaffected by oxytocin administration

in Journal of Affective Disorders (2020), 264(1), 24-28

Background: Emotional dysregulation, a core feature of borderline personality disorder (BPD) has recently been linked to deficits in the cortical representation of bodily signals. Oxytocin modulates the ... [more ▼]

Background: Emotional dysregulation, a core feature of borderline personality disorder (BPD) has recently been linked to deficits in the cortical representation of bodily signals. Oxytocin modulates the salience of external social cues. However, its role in interoception is still not fully understood. The aim of the current study was to replicate reduced heartbeatevoked potentials (HEPs) as a marker for the cortical representation of cardiac signals in BPD and to explore potential effects of oxytocin on HEP amplitude. Methods: Fifty-three medication-free women with a DSM-IV diagnosis of BPD and sixty healthy female controls (HCs) participated in the study. In a randomized, double-blind placebo-controlled trial, participants self-administered either 24 I.U. of oxytocin or placebo and took part in a 5-minute resting-state electrocardiogram (ECG) with parallel electroencephalogram (EEG) measurement. In addition, emotional dysregulation and BPD symptomatology were assessed with self-report questionnaires. Results: Patients with BPD had significantly lower mean HEP amplitudes than HCs. Furthermore, HEP amplitudes were negatively correlated with emotional dysregulation in the whole sample. However, oxytocin had no significant effect on HEP amplitude. Limitations: Only female participants were investigated and no clinicial controls were included. Conclusions: This is the first replication from an independent sample showing a reduced cortical representation of cardiac signals in BPD patients. This, together with other bodyrelated symptoms, suggests deficits in the processing of bodily signals, which seem to be associated with emotional dysregulation. Whether oxytocin influences HEP during emotion regulation tasks needs to be investigated in future studies. [less ▲]

Comment on "Zamariola et al., (2018), Interoceptive Accuracy Scores are Problematic: Evidence from Simple Bivariate Correlations"-The Empirical Data Base, the Conceptual Reasoning and the Analysis behind this Statement are Misconceived and do not Support the Authors' Conclusions.

in Biological Psychology (2020), 152(1), 107870

A recent paper by Zamariola and colleagues is widely cited as an authority on the invalidity of the Heartbeat Counting Task as a measure of interoceptive accuracy. Given the widespread interest in this ... [more ▼]

A recent paper by Zamariola and colleagues is widely cited as an authority on the invalidity of the Heartbeat Counting Task as a measure of interoceptive accuracy. Given the widespread interest in this field, it is essential that papers about methods are conceptually sound. However, only one of the authors' four criticisms appears substantiated - that people count too few heartbeats. Their arguments about "simple bivariate correlations" and their finding that interoceptive accuracy and heart rate correlate, depend on 'spurious correlations' arising from the overlooked point that interoceptive accuracy is a ratio. Moreover, scrutiny of the authors' data shows that their fourth criticism (that interoceptive accuracy is lower on longer trials) is confounded by differences in mean heart rate between trials. We present data from our own labs to refute it. We draw the authors' and editors' attention to these issues and trust that they will reconsider these erroneous conclusions. [less ▲]

Biased perception of physiological arousal in child social anxiety disorder before and after cognitive behavioral treatment

in Clinical Psychology in Europe (2020), 2(2), 2691

Background: A biased perception of physiological hyperreactivity to social-evaluative situations is crucial for the maintenance of social anxiety disorder (SAD). Alterations in interoceptive accuracy (IAc ... [more ▼]

Background: A biased perception of physiological hyperreactivity to social-evaluative situations is crucial for the maintenance of social anxiety disorder (SAD). Alterations in interoceptive accuracy (IAc) when confronted with social stressors may play a role for SAD in children. We expected a biased perception of hyperarousal in children with SAD before treatment and, consequently, a reduced bias after successful cognitive behavioral therapy (CBT). Method: In two centers, 64 children with the diagnosis of SAD and 55 healthy control (HC) children (both 9 to 13 years) participated in the Trier Social Stress Test for Children (TSST-C), which was repeated after children with SAD were assigned to either a 12-week group CBT (n = 31) or a waitlist condition (n = 33). Perception of and worry about physiological arousal and autonomic variables (heart rate, skin conductance) were assessed. After each TSST-C, all children further completed a heartbeat perception task to assess IAc. Results: Before treatment, children with SAD reported both a stronger perception of and more worry about their heart rate and skin conductance than HC children, while the objective reactivity of heart rate did not differ. Additionally, children with SAD reported heightened perception of and increased worry about trembling throughout the TSST-C compared to HC children, but reported increased worry about blushing only after the stress phase of the TSST-C compared to HC children. Children with and without SAD did not differ in IAc. Contrary to our hypothesis, after treatment, children in the CBT group reported heightened perception of physiological arousal and increased worry on some parameters after the baseline phase of the TSST-C, whereas actual IAc remained unaffected. IAc before and after treatment were significantly related. Conclusions: Increased self-reported perception of physiological arousal may play a role in childhood SAD and could be an important target in CBT. However, further studies should examine if this is an epiphenomenon, a temporarily occurring and necessary condition for change, or indeed an unwanted adverse intervention effect. [less ▲]

Childhood trauma affects stress-related interoceptive accuracy

in Frontiers in Psychiatry (2019), 10(1), 750

Early life adversity (ELA) may cause permanent disturbances in brain-body signaling. These disturbances are thought to contribute to physical symptoms and emotional dysregulation in adulthood. The current ... [more ▼]

Early life adversity (ELA) may cause permanent disturbances in brain-body signaling. These disturbances are thought to contribute to physical symptoms and emotional dysregulation in adulthood. The current study investigated the effects of childhood trauma on young adults’ interoceptive accuracy as an indicator of brain-body communication that may be dysregulated by ELA. Sixty-six participants completed an online-questionnaire followed by a laboratory session including the socially-evaluated cold pressor stress test during which ECG, salivary cortisol and interoceptive accuracy were assessed. Childhood trauma was negatively related to interoceptive accuracy (IAc) after the stressor. This stress-effect could not be observed for heart rate and cortisol, which were unrelated to IAc. Participants reporting higher baseline unpleasantness exhibited lower IAc after the stressor, while increases in unpleasantness due to the stressor were associated with higher IAc. Unpleasantness at baseline mediated the effect of childhood trauma on IAc after the stressor. [less ▲]

Respiratory modulation of intensity ratings and psychomotor response times to acoustic startle stimuli

in Neuroscience Letters (2019), 711(1), 134388

Respiratory interoception may play an important role in the perception of respiratory symptoms in pulmonary diseases. As the respiratory cycle affects startle eye blink responses, startle modulation may ... [more ▼]

Respiratory interoception may play an important role in the perception of respiratory symptoms in pulmonary diseases. As the respiratory cycle affects startle eye blink responses, startle modulation may be used to assess visceral-afferent signals from the respiratory system. To ascertain the potential impact of brainstem-relayed signals on cortical processes, we investigated whether this pre-attentive respiratory modulation of startle (RMS) effect is also reflected in the modulation of higher cognitive, evaluative processing of the startle stimulus. Twenty-nine healthy volunteers received 80 acoustic startle stimuli (100 or 105 dB(A); 50 ms), which were presented at end and mid inspiration and expiration, while performing a paced breathing task (0.25 Hz). Participants first responded to the startle probes by 'as fast as possible' button pushes and then rated the perceived intensity of the stimuli. Psychomotor response time was divided into 'reaction time' (RT; from stimulus onset to home button release; represents stimulus evaluation) and 'movement time' time (MT; from home button release to target button press). Intensity judgements were higher and RTs accelerated during mid expiration. No effect of respiratory cycle phase was found on eye blink responses and MTs. We conclude that respiratory cycle phase affects higher cognitive, attentional processing of startle stimuli. [less ▲]

Enhanced Cortical Processing of Cardio-Afferent Signals in Anorexia Nervosa

in Clinical Neurophysiology (2019), 130(9), 1620-1627

Objective: To assess cardiac interoception in anorexia nervosa (AN) using a multidimensional approach. Methods: We assessed the physiological dimensions of cardioception, i.e. the peripheral signal itself ... [more ▼]

Objective: To assess cardiac interoception in anorexia nervosa (AN) using a multidimensional approach. Methods: We assessed the physiological dimensions of cardioception, i.e. the peripheral signal itself (heart rate, HR, and heart rate variability, HRV) and its cortical representation (heartbeat evoked potentials, HEPs), and the psychological dimensions of interoceptive accuracy (heartbeat perception) and interoceptive sensibility (confidence ratings). Electroencephalogram (EEG) and electrocardiogram (ECG) were recorded concurrently during rest and while performing a heartbeat perception task in a sample of 19 female in-patients with AN (DSM-5) and 19 healthy control women (HC). Results: HEPs, defined as mean EEG amplitude in a time window of 455-595 ms after the Rpeak of the ECG, were significantly larger in the AN than in the HC group across conditions (p = .002, d = 1.06). There was a trend toward better heartbeat perception in AN, but no group differences in HR, HRV, and confidence ratings. Conclusions: Individuals with AN showed an interoceptive profile of heightened cortical processing, a trend toward heightened interoceptive accuracy, and unaltered cardiac autonomic activation and interoceptive sensibility. Significance: In terms of neurobiological models of AN, enhanced cortical representations of interoceptive signals might reflect a mechanism, which promotes fasting by alleviating negative body states. [less ▲]