Schizophrenia Research Trends

154A. Orosz, K. Cattapan-Ludewig, G. Gal and J. FeldonRESULTS OBTAINED BY THIS NEW LIRR PARADIGMLIrr in first-episode and acute schizophreniaTo date, there are two published reports (97;100) and an abstract (101) of studies thatapply the new LIrr paradigm ((97; 100):version of A.M.Young, (101): version of G.Gal) tohealthy controls as well as schizophrenia patients. All groups yielded robust LIrr in healthycontrol subjects. Concerning the patient groups, there were some differences between thestudies.Young and collaborators found disrupted LIrr in acute schizophrenia patients who weredrug-free or within 14 days of recommencement of antipsychotic treatment. As comparableresults were produced by LI experiments (20;60;73;81), they reasoned that very similarprocesses may underlie the phenomena of LI and LIrr (97). Furthermore, the found in theirfMRI study that the LIrr paradigm gives rise to activation in brain areas, e.g. the hippocampalformation, which has been shown to be activated also in LI experiments (97).In addition, Gal and coworkers (100) and the group of Orosz (101) tested nevermedicated first-episode acute schizophrenia patients in order to investigate if disrupted LIrr isalready present at the onset of the illness. Both research groups measured disrupted LIrrendorsing the paradigm to be a reliable tool to assess attentional dysfunctions in acuteschizophrenia.LIrr in Chronic SchizophreniaHowever, there were some conflicting outcomes concerning the performance of chronicschizophrenia patients. While Gal and colleagues (100) reported disrupted LIrr also inchronic schizophrenia patients, Young et al. (97) failed to show any learning of the CS-USassociation under either PE or NPE conditions. Young at al. have interpreted these findingsas the result of a general failure of associative learning as it was already reported by Martinset al. (83). However, various LI studies have shown that LI is reinstated in chronicschizophrenia (20;58;73). It has to be noted that the chronic schizophrenia patients involvedin the Gal et al. (100) study were tested during an acute phase, whereas the patients of Younget al. (97) were in a stable “steady” state. Thus, the LIrr disruption measured by Gal et al.might be due to the current acute phase. This might indicate that, as LI disruption (18), LIrrabolition might be seen as a state marker of acute schizophrenia. On the other hand, thefailure of the LIrr paradigm to detect possible slight modulations of associative learning inchronic schizophrenia could also be a limitation on the applicability of this new paradigmwhich is more useful in studies of acute schizophrenia (97).