Cognitive abnormalities and schizophrenic symptoms

Towards integrating phenomenology and neurocognition: Possible neurocognitive correlates of basic self-disturbance in schizophrenia

“…A major theme in this work is the failed suppression of attention to familiar or irrelevant information/stimuli in the environment, leading to aberrant salience of objects and associations [82,83] -or, to reverse the terminology, excessive attention to information that is highly familiar or irrelevant. A number of neurocognitive models and experimental paradigms have produced findings consistent with this view, including the memoryprediction model of cortical function [48,84,85], the salience dysregulation model based on dopamine system abnormalities [55,57,82], mismatch negativity reduction [86], latent inhibition [54,87,88], and Corlett's model of ketamine as a pharmacological model of psychosis [89,90]. Also, Hemsley [58,59,91] and Sass [9] drew on findings regarding malfunction in the hippocampus-based "comparator" system in schizophrenia, proposing that this dysfunction may result in an automatic, hyperreflexive awareness that disrupts the tacit/focal structure essential to normal experience of basic selfhood.…”

“…Broadly speaking, they consist of: 1. source monitoring deficits and 2. aberrant salience (memory-attention disturbances). Recent work on these approaches harks back to the neurocognitive work of the psychologists Frith [52,53], Gray [54][55][56] and Hemsley [57][58][59][60], experimentalists whose views were considered in a phenomenological perspective, and in relationship to self-disturbance in particular, by Sass [9]. These two streams of research will be reviewed in turn before considering ways forward in integrative models, particularly regarding the role of early neurodevelopmental disturbances, primary versus secondary disturbances, and the state versus trait nature of such pathology.…”

“…The notion of "prediction errors" has played an important role in attempts to understand the mechanisms that may underlie source monitoring deficits [52,54,57,59,60,62,63]. These approaches propose that positive psychotic symptoms result from the predictions we make and the extent to which these predictions are fulfilled.…”

“…Keefe and colleagues [48,84,85] recently attempted to introduce an organising principle in studies of cognition in schizophrenia in the form of a "memoryprediction" model of cortical function, which has substantial affinities with the prediction errors models mentioned above, as well as with earlier models proposed by Hemsley [57,58,91] and Gray [55]. The "memoryprediction" model is based on the understanding that perceptual processes do not simply involve the reproduction of stimuli, but that they involve matching and integrating sensory input, which are often fragmented and partial, with "working models" of the world.…”

Aumento da dislogia do discurso em narrativa emocionalmente carregada na esquizofrenia

“…No entanto, esta tarefa se complica quando o paciente tem de utilizar um feedback contínuo entre dados externos que lhe estão sendo oferecidos e a reformulação da estratégia e do raciocínio em curso, quando então tem-se que operacionalizar conjuntamente: 1º -dados internos cognitivos, 2º -situações novas externas e 3º -o tratamento afetivo-cognitivo destes "inputs" externos (checar se já foram vividos ou não; se a situação se encaixa ou não com estratégias anteriores; se é uma situação neutra, prazerosa ou desagradável, -como exemplos) e aí o processo conjunto é rompido. Mais uma vez, uma dissinergia fronto-límbica (sobretudo fronto-hipocâmpica) 31 é evocada para se explicar global e articuladamente estes fatos.…”