Abstract: Recent studies have shown that schizophrenia may be a disease affecting the states of consciousness. The present study is aimed at investigating metamemory, i.e., the knowledge about one's own memory capabilities, in patients with schizophrenia. The accuracy of the Confidence level (CL) in the correctness of the answers provided during a recall phase, and the predictability of the Feeling of Knowing (FOK) when recall fails were measured using a task consisting of general information questions and assessing semantic memory. Nineteen outpatients were paired with 19 control subjects with respect to age, sex, and education. Results showed that patients with schizophrenia exhibited an impaired semantic memory. CL ratings as well as CL and FOK accuracy were not significantly different in the schizophrenic and the control groups. However, FOK ratings were significantly reduced for the patient group, and discordant FOK judgments were also observed more frequently. Such results suggest that FOK judgments are impaired in patients with schizophrenia, which confirms that schizophrenia is an illness characterized by an impaired conscious awareness of one's own knowledge

Abstract: Based on recent insight into the thalamocortical system and its role in perception and conscious experience, a unified pathophysiological framework for hallucinations in neurological and psychiatric conditions is proposed, which integrates previously unrelated neurobiological and psychological findings. Gamma-frequency rhythms of discharge activity from thalamic and cortical neurons are facilitated by cholinergic arousal and resonate in networks of thalamocortical circuits, thereby transiently forming assemblies of coherent gamma oscillations under constraints of afferent sensory input and prefrontal attentional mechanisms. If perception is based on synchronisation of intrinsic gamma activity in the thalamocortical system, then sensory input to specific thalamic nuclei may merely play a constraining role. Hallucinations can be regarded as underconstrained perceptions that arise when the impact of sensory input on activation of thalamocortical circuits and synchronisation of thalamocortical gamma activity is reduced. In conditions that are accompanied by hallucinations, factors such as cortical hyperexcitability, cortical attentional mechanisms, hyperarousal, increased noise in specific thalamic nuclei, and random sensory input to specific thalamic nuclei may, to a varying degree, contribute to underconstrained activation of thalamocortical circuits. The reticular thalamic nucleus plays an important role in suppressing random activity of relay cells in specific thalamic nuclei, and its dysfunction may be implicated in the biological vulnerability to hallucinations in schizophrenia. Combined with general activation during cholinergic arousal, this leads to excessive disinhibition in specific thalamic nuclei, which may allow cortical attentional mechanisms to recruit thalamic relay cells into resonant assemblies of gamma oscillations, regardless of their actual sensory input, thereby producing an underconstrained perceptual experience. Key Words: Charles Bonnet syndrome; gamma oscillations; hallucinations; late paraphrenia; Lewy body dementia; perception; schizophrenia; thalamocortical system

Abstract: Empirical approaches on topics such as consciousness, self-awareness, or introspective perspective, need a conceptual framework so that the emerging, still unconnected findings can be integrated and put into perspective. We introduce a model of self-consciousness derived from phenomenology, philosophy, the cognitive, and neurosciences. We will then give an overview of research data on one particular aspect of our model, self-agency, trying to link findings from cognitive psychology and neuroscience. Finally, we will expand on pathological aspects of self-agency, and in particular on psychosis in schizophrenia. We show, that a deficient self-monitoring system underlies, in part, hallucinations and formal thought (language) disorder in schizophrenia. We argue, that self-consciousness is a valid construct and can be studied with the instruments of cognitive and neuroscience

Abstract: Schizophrenia, like other pathological conditions of mental life, has not been systematically included in the general study of consciousness. By focusing on aspects of chronic schizophrenia, we attempt to remedy this omission. Basic components of Husserl’s phenomenology (intentionality, synthesis, constitution, epoche, and unbuilding) are explicated and then employed in an account of chronic schizophrenia. In schizophrenic experience, basic constituents of reality are lost and the subject must try to explicitly re-constitute them. “Automatic mental life” is weakened such that much of the world that is normally taken-for-granted cannot continue to be so. The subject must actively re-lay the ontological foundations of reality