Self-other recognition impairments in individuals with schizophrenia: a new experimental paradigm using a double mirror

A comparison of clinical characteristics and course predictors in early- and childhood-onset schizophrenia

AIM

The aim of this study was to compare the clinical characteristics of childhood-onset schizophrenia (COS) and early-onset schizophrenia (EOS) during the first- episode psychosis and the stable period, to examine psychopharmacological treatment approaches, and to investigate potential predictive factors for prognosis.

METHODS

Demographic, clinical, and psychopharmacological therapy data for 31 patients diagnosed with COS and 66 with EOS were retrieved from the file records in this multicenter study. Symptom distribution and disease severity and course were evaluated twice, in the acute psychotic stage and in the latest stable phase, during follow-up using the positive and negative syndrome scale (PANSS) and clinical global impression (CGI) scales.

RESULTS

A statistically significant difference was observed between the groups' CGI improvement rates and median last stable stage PANSS positive, negative, and general psychopathology symptom scores (p = .005, p = .031, p = .005, and p = .012, respectively). Premorbid neurodevelopmental disorder and obsessive-compulsive disorder and comorbidities were more common in the COS group (p = .025 and p = .030, respectively), and treatment required greater multiple antipsychotic use in that group (p = .013). When the independent variables affecting the difference between pre- and post-treatment PANSS scores were examined using linear regression analysis, the model established was found to be statistically significant (F = 5.393; p = .001), and the group variable (p = .024), initial disease severity (p = .001), and socioeconomic level (p = .022; p = .007) emerged as predictive factors for the disease course.

CONCLUSION

Although early diagnosis and treatment is an important factor in improving prognosis in schizophrenia, more specific predictors for schizophrenia need to be identified. Additionally, preventive programs and pharmacological methods need to be developed in children with neurodevelopmental problems, particularly those from low socioeconomic status families.

Beyond peripersonal boundaries: insights from crossmodal interactions

We experience our self as a body located in space. However, how information about self-location is integrated into multisensory processes underlying the representation of the peripersonal space (PPS), is still unclear. Prior studies showed that the presence of visual information related to oneself modulates the multisensory processes underlying PPS. Here, we used the crossmodal congruency effect (CCE) to test whether this top-down modulation depends on the spatial location of the body-related visual information. Participants responded to tactile events on their bodies while trying to ignore a visual distractor presented on the mirror reflection of their body (Self) either in the peripersonal space (Near) or in the extrapersonal space (Far). We found larger CCE when visual events were presented on the mirror reflection in the peripersonal space, as compared to the extrapersonal space. These results suggest that top-down modulation of the multisensory bodily self is only possible within the PPS.

Self/other distinction in adolescents with autism spectrum disorder (ASD) assessed with a double mirror paradigm

BACKGROUND

Self/other distinction (SOD), which refers to the ability to distinguish one's own body, actions, and mental representations from those of others, is an essential skill for effective social interaction. A large body of clinical evidence suggests that disruptions in SOD may be key to social communication deficits in individuals with autism spectrum disorders (ASD). In particular, egocentric biases have been found in cognitive, affective, behavioural, and motor domains. However, research in this area is scarce and consists of recognition paradigms that have used only static images; these methods may be insufficient for assessing SOD, given the increasing role of embodiment in our understanding of the pathophysiology of ASD.

METHOD

A single-centre, prospective pilot study was carried out to investigate, for the first time, self-recognition and SOD in seven adolescents with ASD compared with matched, typically developing controls (TDCs) using the "Alter Ego"TM double mirror paradigm. The participants viewed a double mirror in which their own face was gradually morphed into the face of an unfamiliar other (self-to-other sequence) or vice versa (other-to-self sequence); participants were instructed to indicate at which point the morph looked more like their own face than the other's face. Two judgement criteria were used: 1) M1: the threshold at which subjects started to recognize their own face during the other-to-self morphing sequence; 2) M2: the threshold at which subjects started to recognize the other's face during the self-to-other morphing sequence.

RESULTS

Consistent with the predictions, the results showed that the participants with ASD exhibited earlier self-recognition in the other-to-self sequence and delayed other-recognition in the self-to-other sequence, suggesting an egocentric bias. SOD impairments were also marginally correlated with ASD severity, indicating earlier face recognition in more severely affected individuals. Furthermore, in contrast with that of TDCs, the critical threshold for switching between self and other varied with the direction of morphing in ASD participants. Finally, these differences in face recognition and SOD using mirrors, unlike previous research using static images, support the central place of bodily self-consciousness in SOD impairments.

CONCLUSIONS

Although additional research is needed to replicate the results of this preliminary study, it revealed the first behavioural evidence of altered SOD in ASD individuals on an embodied, semiecological face-recognition paradigm. Implications for understanding ASD are discussed from a developmental perspective, and new research and therapeutic perspectives are presented.

Looking within: Interoceptive sensibility in young adults with psychotic-like experiences

AIM

Interoception is the ability to sense internal bodily changes and research indicates that it may play a role in the development of mental illness. In recent years, preliminary evidence has shown that interoception is impaired in people with psychosis. Interoceptive sensibility, a meta-cognitive aspect of interoception, has never been studied across the psychosis continuum. The present study aimed at assessing interoceptive sensibility in youth with psychotic-like experiences.

METHOD

We invited a sample of young adults (N = 609; age 19-21 years) to complete an online survey that included a measure of interoceptive sensibility (the Multidimensional Assessment of Interoceptive Awareness-2) and the Community Assessment of Psychotic Experiences-Positive Scale -15 (CAPE-P15). Using the recommended cutoff for the CAPE-P15, the overall sample was divided into two groups (high/low risk for psychosis).

RESULTS

Significant group differences were observed in several dimensions of interoceptive sensibility. A logistic regression analysis indicated that scores in the subscales of Not-Distracting, Not-Worrying, Attention-Regulation, Emotional Awareness, Body Listening, and Trusting significantly predicted increased risk for psychosis.

CONCLUSION

Abnormal interoceptive sensibility may be a vulnerability marker for psychosis. These results, however, await further validation from additional comprehensive, longitudinal studies. Enhanced interoceptive sensibility has been reported following contemplative training, thus creating opportunities for future interventions to delay or prevent psychotic illness.

Neural Correlates of Self-other Distinction in Patients with Schizophrenia Spectrum Disorders: The Roles of Agency and Hand Identity

Schizophrenia spectrum disorders (SSD) are characterized by disturbed self-other distinction. While previous studies associate abnormalities in the sense of agency (ie, the feeling that an action and the resulting sensory consequences are produced by oneself) with disturbed processing in the angular gyrus, passive movement conditions to isolate contributions of motor predictions are lacking. Furthermore, the role of body identity (ie, visual features determining whether a seen body part belongs to oneself) in self-other distinction is unclear. In the current study, fMRI was used to assess the roles of agency and hand identity in self-other distinction. Patients with SSD and healthy controls (HC) performed active and passive hand movements (agency manipulation) while seeing their own or someone else's hand moving in accordance with their action (hand identity manipulation). Variable delays (0-417 ms) between movement and feedback had to be detected. Our results showed overall lower delay detection performances during active than passive conditions; however, these differences were reduced in patients when the own hand was displayed. On a neural level, we found that in HC, activation in the right angular gyrus was modulated by agency and hand identity. In contrast, agency and hand identity revealed no overlapping activation in patients, due to reduced effects of agency. Importantly, HC and SSD patients shared similar effects of hand identity in the angular gyrus. Our results suggest that disturbances of self-other distinction in SSD are particularly driven by agency, while self-other distinction based on hand identity might be spared.

Exploring Self-Consciousness From Self- and Other-Image Recognition in the Mirror: Concepts and Evaluation

A historical review of the concepts of self-consciousness is presented, highlighting the important role of the body (particularly, body perception but also body action), and the social other in the construction of self-consciousness. More precisely, body perception, especially intermodal sensory perception including kinesthetic perception, is involved in the construction of a sense of self allowing self-other differentiation. Furthermore, the social other, through very early social and emotional interactions, provides meaning to the infant's perception and contributes to the development of his/her symbolization capacities. This is a necessary condition for body image representation and awareness of a permanent self in a time-space continuum (invariant over time and space). Self-image recognition impairments in the mirror are also discussed regarding a comprehensive developmental theory of self-consciousness. Then, a neuropsychological and neurophysiological approach to self-consciousness reviews the role of complex brain activation/integration pathways and the mirror neuron system in self-consciousness. Finally, this article offers new perspectives on self-consciousness evaluation using a double mirror paradigm to study self- and other- image and body recognition.

Uncanny Mirroring: A Developmental Perspective on the Neurocognitive Origins of Self-Disorders in Schizophrenia

Varieties of anomalous subjective experiences, i.e. "basic self-disorders" (SDs), have been empirically demonstrated as core clinical features of schizophrenia spectrum disorders, predating full-blown psychotic symptoms. However, the clinical stage in which SDs emerge and their putative neurocognitive origins remain unsolved issues. Focusing on a prototypical anomalous mirror experience (i.e., a stable, trait-like subjective feeling of nonexisting while looking at oneself in the mirror) reported by an 11-year-old boy at familial high risk for schizophrenia and diagnosed as attenuated psychosis syndrome, we outline some possible developmental pathways leading to SDs. Such pathways are hypothesized in accordance with the documented early impairments in perceptual integration across distinct modalities in children at risk for schizophrenia spectrum disorders and to the specific features of mirror experience as provided by phenomenological and developmental psychology perspectives. We conclude that SDs could presumably have an early developmental origin, although children become progressively more aware of them. Although further hypothesis testing in clinical samples and longitudinal empirical investigation of at-risk children is badly needed, we propose that age-appropriate, phenomenologically oriented assessment of SDs could be useful for the early identification of psychotic risk.