Hallucinatory experience as aberrant event memory formation: Implications for the pathophysiology of schizophrenia

Neural and neuronal discoordination in schizophrenia: From ensembles through networks to symptoms

“…Second, the disorganization aspect of schizophrenia might constitute a dimension separate from positive symptoms . Third, the boundaries between symptom categories might not hold, as hallucinations, delusions, disorganization and some aspects of negative symptoms may in fact be secondary and stem from underlying cognitive dysfunctions . Fourth, many abnormalities are well documented in patients and their first‐degree relatives, but they are not included in the diagnosis of schizophrenia.…”

“…Schizophrenia is associated with alterations of oscillatory patterns in population activity in multiple brain areas, These oscillations provide “neural syntax” for meaningful processing of sequential neuronal ensemble activity and time windows for synaptic plasticity . Inappropriate timing of spiking activity manifested as altered oscillations may give rise to corrupted ensemble code, maladaptive synaptic plasticity and schizophrenia symptoms . In the hippocampus, input from CA3 is associated with the dominance of slow gamma (25‐55 Hz) over fast gamma (60‐100 Hz) oscillations and controls memory recollection .…”

Hippocampus as a wormhole: gateway to consciousness

“…Faw and Faw propose that CA3 and the dentate gyrus ‘serve complementary functions, relating the current episode to a previous one,’ and that it is CA1 where the ‘ongoing scene’ is built . The contrasting position is that conscious experience is a manifestation of the formation of event memory codes in CA3 . Attractor dynamics in the CA3 autoassociation network produces a unique pattern of neuronal activity at every theta cycle, a pattern that is recorded as an event memory (but not necessarily retained for more than seconds) and that can be conceived of as a complex symbol.…”

“…Importantly, it is not consciousness that shapes or guides behavior but the neural process that underpins consciousness (I did not suggest that ‘subjective reality shapes behaviour’). Consciousness is merely a complex symbol that references an event memory code and describes the pattern that has just emerged in the CA3 network …”

Mind‐body problem and hippocampus

“…Event memory (episodic memory) formation has been linked specifically to CA3 (rather than CA1), and it is the formation of these memories that we experience as consciousness. Hallucinations, dreaming, recollection of memories, and outcome imagery involve recombination of previously formed event memories, and these phenomena too have been linked specifically to CA3 . In dreaming, CA3 may be temporarily uncoupled from CA1, but this would not affect the autoassociation process in CA3, which is active in dreaming .…”