Study of Instability of Emotional Processing in Schizophrenia and Non-Psychotic relatives. Possible New Utility of Single Trial fMRI

DRUCAROFF, LUCAS JAVIER; VILLARREAL, MIRTA; WAINSZTEIN, AGUSTINA; CASTRO, MARIANA NAIR; COSTANZO, ELSA; BRUSCO, LUIS IGNACIO; BUSATTO FILHO, GERALDO; NEMEROFF, CHARLES; GUINJOAN, SALVADOR

Buenos Aires

Conferencia; Schizophrenia International Research Society (SIRS) - South American Conference - 2014; 2014

Schizophrenia International Research Society (SIRS).

Instability of information processing at individual level in schizophrenia has been suggested in studies that used fMRI1 and response time variability2 during performance of cognitive tasks.Interestingly, this deficit was correlated to work ability in schizophrenia patients2.Also, patients with schizophrenia decided more inconsistently in stimulus preference tasks, for both affective and non-affetive stimuli3.Moreover, it?s been seen that generalization of a learned concept is altered in these patients4. Which could explain more unstable processing of information.Traditional fMRI assumes that a similar stimulus, when repeated, will activate the same areas in the brain at individual and group level.Single trial fMRI is a novel technique, which does not focus on locating the activation but in categorizing the stimuli acording to their pattern of bran response.Eleven (11) subjects with diagnosis of shizophrenia and nine (9) healthy controls underwent fMRI scans.Each session consisted in three 7-minute runs in which they were shown emotional stimuli (faces) of three different categories: happy, sad and neutral faces. Eight of each condition per run.They were not required to answer about the emotion expressed in the image. A control question (gender of the latest face) randomly appeared in the screen to prove participant?s were paying attention to the task.Single Trial fMRI analysis was developed, in our work, for emotional stimuli categorization.Accuracy of Single Trial fMRI was above chance for both, healthy controls and schizophrenia patients, in all three pairwise categorizations (Figure 2, One Sample t test Vs. Chance, all p