Evaluación de las Anomalías Perceptuales en pacientes esquizofrénicos y sus familiares de primer grado

Abstract

According to the strategy for the genetic studies of Schizophrenia, there is the search of biological markers or quantitative phenotypes. These phenotypes could indicate the existence of alterations in probands's relatives, which are not sick, but share the genetic predisposition to the schizophrenia.The suppression of wave P50 as a sensory gating marker is among these well known indicators which is altered in sick people and in their first degree relatives. The dysfunction in gating and filtering sensory stimuli underlines the abnormalities of perception, striking increase in awareness of background and a perceived increase in the intensity of color and light.
Bunney et al . developed a scale in order to measure the perceptual anomalies as distinct from the hallucinations: "Structured Interview
for Assessing Perceptual Anomalies (SIAPA); where the symptoms of disturbance like hypersensitivity, flooding and selective attention to external stimuli are explored. This scale was applied to 31 schizophrenic patients, 57 first-degree relatives of schizophrenic people and 79 normal controls with no history psychiatric illness in their families in order to determine the prevalence of perceptual anomalies. To determine the possible association between perceptual anomalies and clinical symptoms the PANSS scale (Positive and Negative
Syndrome Scale) was assessed in patients and their relatives. A greater percent of auditive and visual disturbances was found in patients and first degree relatives respect to control group. Schizophrenic patients and their first-degree relatives groups showed no difference in the prevalence of auditory and visual anomalies . The presence of perceptual anomalies in patients and relatives could be used as biological markers for future genetic studies.