Towards a Neurophenomenological Understanding of Self-Disorder in Schizophrenia Spectrum Disorders: A Systematic Review and Synthesis of Anatomical, Physiological, and Neurocognitive Findings

Global neural self-disturbance in schizophrenia: A systematic fMRI review

There is a general consensus that schizophrenia (SZ) is characterized by major changes in the sense of self. Phenomenological studies suggest that these changes in the sense of self stem from a basic disturbance, hence the term 'basic self-disturbance'. While imaging studies demonstrate changes in various regions during self-focused tasks, the exact neural correlates of such basic self-disturbances remain unclear. If the self-disturbance is indeed basic and thereby underlies all other symptoms, one would expect it to be related to more global rather than local changes in the brain. Testing this hypothesis, we conducted a systematic review of fMRI studies on self in SZ. Our main findings are 1. Abnormal activity related to the self can be observed in a variety of different regions ranging from higher-order transmodal to lower-order unimodal regions, 2. These findings hold true across different tasks including self-reflection, self-referentiality, and self-agency, and 3. The global neural abnormalities related to the self in SZ correspond to all layers of the self, predominantly the mental and exteroceptive self. Such global neural disturbance of self converges well with the basic self-disturbance as described in phenomenology.

Anomalies of imagination and development of psychosis: A phenomenological account

In 20th century psychiatry, various disturbances of imagination were discussed in the context of schizophrenia. Today, these notions have almost completely vanished from mainstream psychopathology. However, recent work has suggested that specific phenomena within this area have a relevance for differential diagnosis and early detection of psychosis. This paper first provides an overview of 20th century psychopathological literature, as well as more recent neurocognitive studies, addressing disturbances of imagination and their role for symptom formation in schizophrenia. It then discusses recent empirical investigations of subjective anomalies of imagination in schizophrenia-spectrum disorders and suggests a clinical-phenomenological account of their role in the development of psychotic symptoms. Empirically and conceptually, these subjective anomalies are linked with disturbances of basic self. Patients' descriptions of the development of their anomalous experiences and symptoms indicate that increased spatial (object-like) articulation and instability of the first-personal manifestation of imaginative experience can be involved in the emergence of delusions and hallucinatory phenomena. Finally, a potential link between subjective anomalies of imagination and the neurocognitive construct of source monitoring deficits is discussed.