A neural model of the loss of self in schizophrenia

Abstract

Numerous researchers have pointed out over the last decades that there is a loss of the sense of the inner self in schizophrenia. In particular, the illuminating article of Sass et al. gives an underpinning explanation of the disease along these lines in each of its 3 manifestations, with positive, negative, or disordered symptoms. The crucial component of the analysis of these researchers is that of various disturbances in ipseity (the ongoing sense of "being there" accompanying all conscious experience) that can occur for a sufferer, giving a framework with which to understand the disease. Such analyses of schizophrenia in terms of distortions of the self go back much earlier. However, the more recent work has become more precise and embracing in terms of seeing most forms of schizophrenia as arising from such distortions. It also provides new ways of looking at and diagnosing the disease. In this article we propose to move the whole analysis closer into the brain itself by means of the CODAM neural network model of consciousness (where CODAM is an acronym for the "COrollary Discharge of Attention Movement" model of consciousness creation, to be described later). This allows both a mechanism to be formulated as to the basic brain-based cause of schizophrenia (with varieties of this cause correlated with the 3 main forms of it) as well as open up possible lines of research to be followed to help ameliorate the attention defects exposed in this approach.

Figures

Fig. 1.

The Ballistic Control Model of Attention. PFC, prefrontal cortex; SPL, superior parietal lobe; TPJ, tempero-parietal junction; VCX, visual cortex.

Fig. 2.

The Extended Ballistic Attention Control model, with activity on the extra working memory buffer (beyond the modules in figure 1) allowing for further use of the representation of the attended stimulus, for reasoning, thinking, and so on, by the subject. WM, working memory.

Fig. 3.

The CODAM (COrollary Discharge of Attention Movement) Model.

Fig. 4.

The Full CODAM Model of the Control of Attention. The action of the various modules of this figure and the relation to those in figure 3, are explained in the text., CODAM, COrollary Discharge of Attention Movement; IMC, inverse model controller.