Intentionality as a link between the neuropsychology and the symptoms of schizophrenia

The need for systematic ethnopsychology: The ontological status of mentalistic terminology

The conceptual foundations and ontology of cognitive neuroscience are rarely analysed in cross-cultural perspective, although they are manifestly the outcome of historical currents in specifically Western psychological science. How robust such concepts are, and how generalizable to other cultures, is thus quite problematic. Users of empirical techniques in imaging neuroscience are now actively exploring such topics as attention, volition, emotion and empathy, but with little awareness of how well or badly these concepts can be translated. This essay addresses issues of cultural bias and the potentially misleading use of extended metaphors in the typical deployment of mentalistic terminology, and suggests that there may be alternative conceptualizations, perhaps inspired by phenomenology, which would have less cultural baggage. Ultimately, the most scientifically useful ontology for interpreting and predicting human action may result from an integration of high quality ethnographic reports of mentalistic concepts and terminology found in other cultures. Social and cultural anthropologists are urged to prioritize the identification of such concepts during their fieldwork experience.

Ego disturbances in the sense of Kurt Schneider: historical and phenomenological aspects

The phenomena which were grouped together by Kurt Schneider to constitute the ego disturbances have always been of particular diagnostic relevance for schizophrenia. The manner in which these symptoms are described and distinguished from other psychopathological symptoms has generally been rather imprecise. The introduction of phenomenological methods into the field of psychiatry led to considerable improvements in symptom descriptions and to a clearer distinction between psychotic and nonpsychotic experience. Continued developments in phenomenology have further incorporated aspects of schizophrenic symptom development and in doing so have brought so-called transitional phenomena and the core schizophrenic syndrome into focus. The ego disturbances accordingly appear to stem from a particular form of depersonalization which is described as a modified sense of mineness and which can be distinguished from the neurotic experience of depersonalization.

[The psychopathology of ego disturbances: history and phenomenology]

The phenomena which Kurt Schneider grouped together to form the ego disturbances have always been of particular diagnostic relevance for schizophrenia. While little importance was historically attached to accurately describing and distinguishing psychopathological symptoms, Karl Jaspers' and Kurt Schneider's descriptive psychopathology aims to draw a sharp yet differentiated distinction between psychotic and non-psychotic disorders at the symptom level. New developments in phenomenology including aspects of symptom development are presented. The depersonalization experience is focused on as a transitional phenomenon which is distinguishes from neurotic depersonalization through a disturbed sense of mineness. The ego disturbances indicate that disturbed mineness can be seen as the common denominator of first-rank symptoms of schizophrenia.

The temporal structure of intentionality and its disturbance in schizophrenia

Working memory, attention and executive control functions are central areas of neuropsychological research in schizophrenia. These concepts implicitly refer to the basic temporal structure of mental life as an integration of past, present and future. From a phenomenological point of view, they may be paralleled to the structure of internal time consciousness as analyzed by Husserl, consisting of a retentional, presentational and protentional function. These synthetic functions, operating at the most basic layer of consciousness, are capable of integrating the sequence of single moments into an 'intentional arc', enabling us to direct ourselves towards objects and goals in a meaningful way. On this background, basic symptoms of schizophrenia such as formal thought disorder, loss of automatic performances and disturbances of self-awareness may be conceived as caused by a weakening and dissolution of the intentional arc. A failure of the continuous intertwining of succeeding moments, and especially of the protentional function, leads to a loss of the tacit or operative intentionality that carries the acts of perceiving, thinking and acting. The loss of tacit, implicit functions undermines the common-sensical understanding of reality and has to be compensated by the deliberate, hyperreflexive reconstruction of everyday performances. Phenomenological analyses may thus establish a link between experimental research on single mental dysfunctions on the one hand and the higher level of the patient's subjective experience on the other.