Exploring the Contribution of Interoception Dissociation, Anxiety and Depression

This thesis explores the multifaceted role of **interoception** in psychological distress, focusing on dissociation, anxiety, and depression. Interoception, defined as the perception, interpretation, and regulation of internal bodily signals (such as heartbeats and visceral sensations), is central to emotional and cognitive functioning and self-awareness. Disruptions in this process (interoceptive dysfunction) are strongly implicated in various psychiatric conditions. Drawing on the **Interoceptive Predictive Processing (IPP) model** and the **Tripartite Model** (Interoceptive Accuracy [IAc], Sensibility [IS], and Awareness [IAw]), this research pursues two primary objectives: 1) to systematically examine the association between interoception and dissociation; and 2) to empirically investigate whether regular **sport practice** moderates the relationship between interoceptive sensibility and emotional distress (anxiety and depression). Study 1 was a systematic review that synthesized evidence regarding the link between interoception and dissociation. The review found that the association is nuanced and context-dependent, varying based on the interoceptive component measured and the type of dissociation assessed. While findings concerning IAc (objective performance) were inconsistent, IAc deficits were often associated with depersonalization when measured by robust tasks like the Heartbeat Discrimination Task (HDT) or Heartbeat Detection Task (HBD). In contrast, **IS impairments**, particularly diminished scores on the Multidimensional Assessment of Interoceptive Awareness (MAIA) subscales of *Trusting* and *Not-Distracting*, consistently predicted dissociation in clinical populations, including Functional Neurological Disorder (FND), Depersonalization-Derealization Disorder (DDD), and Post-Traumatic Stress Disorder (PTSD). Furthermore, functional seizure (FS) patients often exhibited high **Interoceptive Trait Prediction Error (ITPE)** (when perceived ability exceeded actual performance), which correlated with increased dissociative symptoms. Electrophysiological markers, such as reduced **Heartbeat-Evoked Potential (HEP) amplitude**, were observed in patients with DPD and Borderline Personality Disorder (BPD). Study 2 employed a cross-sectional, correlational design with 111 participants (university students and others) to examine the moderating role of sport practice on the relationship between IS (MAIA subscales) and emotional distress (Hospital Anxiety and Depression Scale [HADS] scores). Sport practitioners reported significantly lower anxiety and depression scores, and higher MAIA *Self-Regulation* scores, compared to non-practitioners. Crucially, moderation analyses revealed that **sport practice significantly attenuated the association between specific dimensions of IS and anxiety**. Among **non-practitioners**, higher IS scores on *Noticing* and *Emotional Awareness* were positively associated with elevated anxiety levels (e.g., *Noticing*: b = 1.59, *p* < .001). However, these associations were non-significant among **sport practitioners**. No significant moderation effects were found for depressive symptoms. Collectively, these findings reinforce an embodied view of mental health. They support the IPP framework, suggesting that dissociation may stem from a failure to minimize interoceptive prediction errors, leading to a fragmented self-perception. The results from Study 2 indicate that **regular sport engagement serves as a protective scaffold** for interoceptive learning, potentially promoting more accurate prediction calibration and reducing the maladaptive interpretation of bodily signals as threatening. This thesis concludes that interventions targeting IS, such as embodied practices and sport, hold promise for fostering interoceptive and emotional resilience.