September 2015, reputable source:
"Neurobiological Models of
Self-Disorders in Early Schizophrenia
Self-disorders (SDs) (from the German Ichstörungen) are alterations of the first-person perspective, long associated with schizophrenia, particularly in early phases."
http://schizophreniabulletin.oxfordjournals.o..."
Disorders of the Self : New Therapeutic Horizons: The Masterson Approach"
https://books.google.ch/books?id=PytkjA3HNqQC..."Understanding the Self
[...]
...from Freud’s original understanding of ‘Das Ich' translated into English as Ego, to the modern views of ‘
self' and self object’."
https://www.conted.ox.ac.uk/C800-110The Phenomenological Mind
An Introduction to Philosophy of Mind and Cognitive Science
Shaun Gallagher and Dan Zahavi, first published 2008 by Routledge.
"Let us look at a more dramatic case of disturbed self-experience, namely schizophrenia. Although the most recent versions of the psychiatric diagnostic systems (DSM-IV and ICD-10) do not include a reference to the self, varieties of
self-disorders have always figured, at least implicitly, as an important component in the clinical picture of schizophrenia. As early as 1913, the concept of ‘Ichstörungen’ (disturbances of the self) was introduced by Jaspers."