Visual backward-masking performance in a longitudinal study of early onset schizophrenia

The aim of the present study was to examine the effect of visual backward-masking (VBM) in patients with early onset schizophrenia (EOS, n=28) compared to healthy controls (n=80) at baseline and at one- and two-year follow-ups. Seventeen patients and 40 controls performed a VBM task at all three sessions, which included five different interstimuli intervals (ISI) at 16.5, 33.5, 49.5, 116 and 166 ms, and an additional no-masking control task. Patients with EOS revealed no impairment of VBM performance at baseline and at the two follow-ups compared to healthy controls at one- and two-year follow-ups. However, the patients demonstrated a deficit of simple early visual processing. Both groups showed effects of development over a period of 24 months for the shortest ISIs.