Dissociation and interoception in functional neurological disorder

Abstract

Introduction: We aimed to examine susceptibility to dissociation and the impact of dissociation on interoceptive processing in individuals with functional neurological disorder (FND). We hypothesised that dissociative states would be elevated and interoceptive accuracy and awareness impaired at baseline in people with FND, and that such differences would be exacerbated following acute dissociation. Methods: Nineteen adults with FND were compared to 20 healthy controls. A modified heartbeat tracking task measured interoceptive accuracy and awareness (confidence) before and after a validated dissociation induction procedure. An exteroceptive processing control task was included. Mann-Whitney tests and r-values (effect size) were computed for between-group comparisons. Results: The FND group displayed elevated dissociation at baseline (p = 0.001, r = 0.528) compared to controls which increased following dissociation-induction (p < 0.001, r = 0.663). Interoceptive accuracy did not differ between groups at baseline (p = 0.967, r = 0.009); however, the FND group had lower accuracy scores postinduction (p = 0.021, r = 0.379). A negative correlation (trend) between change scores for dissociation and interoceptive accuracy was noted (r s = −0.411, p = 0.057). Confidence ratings on interoceptive and exteroceptive processing tasks were lower in the FND group (p-values < 0.05 or <0.01, r-values 0.331-0.489). Conclusions: Individuals with FND experienced greater susceptibility to dissociation, metacognitive deficits and impaired interoceptive accuracy than controls after acute dissociation.

Individual differences in interoceptive accuracy and prediction error in motor functional neurological disorders: ADTIstudy

“…While the primary goal of this study was to investigate white matter-cardiac interoception relationships in patients with mFND, it is important to contextualize the behavioral findings. Previous studies provided evidence for cardiac interoceptive deficits in FND (Koreki et al, 2020;Ricciardi et al, 2014), while the present and two other studies did not find cardiac interoception deficits in mFND (Jungilligens et al, 2019;Pick, Rojas-Aguiluz, et al, 2020). There may be several explanations for these mixed findings.…”

“…Mismatches between subjective and objective symptom reports in FND‐movt patients have also been described (Pareés et al, 2012). Using a heartbeat detection task, interoceptive accuracy deficits have been reported in both FND‐seiz (Koreki et al, 2020) and FND‐movt (Ricciardi, Demartini, Crucianelli, Edwards, & Fotopoulou, 2014) cohorts, although a lack of group‐level differences has also been characterized in other studies (Jungilligens et al, 2019; Pick et al, 2020). In a study by Koreki and colleagues, discrepancies between interoceptive accuracy and self‐reported bodily awareness (an index of interoceptive trait prediction error [ITPE]) correlated with dissociation severity, underscoring the relevance of this measure (Koreki et al, 2020).…”

#3100 A service evaluation of the experiences of patients with functional neurological disorders within the NHS

“…Lehn et al (38) survey of healthcare practitioners linked these negative perceptions to a fundamental lack of knowledge or misunderstanding of what FND is. This is likely due to the precise aetiology of FND still remaining uncertain, although more recent research has begun to highlight the role of interacting psychological and physiological mechanisms (45,46).…”

Strange face illusions: A systematic review and quality analysis

“…Four studies focussed on associations between SFIs and empathy [14], spirituality [15] and dissociative experiences [16,17]. Five studies used the mirror-gazing task as a method to induce dissociation [18][19][20][21][22]. Abbreviations: MGT -Mirror Gazing Task; IGDT -Inter-personal Gazing Dyad Task…”

“…The MGT, Fig 3(A), involves a seated participant, positioned approximately 0.4m from a standard, frontal plane mirror positioned at eye-level. A light source is placed on the floor behind the participant, which contains a 20-watt incandescent bulb, resulting in a lux level of 0.8 lux (to 1 lux) at the face [1,4,5,[8][9][10][11][12][13][14][18][19][20][21][22]. A variation of the MGT was conducted using a split-mirror made up of two mirrors, measuring 0.2 m by 0.4 m, which were mounted sideby-side with a 4 mm gap between them [6].…”