The aim of this study was to determine the dependency of the P300 component on WM load in a sample of SZ subjects.

Trial time sequences for 0-, 1- and 2- back conditions. The symbol * shows the target number during each trial. We used three external flat electrodes to monitor eye movements (two above and below the left eye and one 3 cms. Recordings were sampled at 1000 Hz and band-pass filtered between 0.1 and 100 Hz using an on-line amplifier.

Trials with undesired eye movements and eye blink artifacts were eliminated from the analysis using a semi-automatic and manual block rejection procedure.

Working memory (WM) tasks usually elicit a P300 ERP component, whose amplitude decreases with increasing WM load.

So far, this effect has not been studied in schizophrenics (SZs), a group that is considered to have an aberrant brain connectivity and impairments in WM capacity.

Neuroinhibition is suggested as an overarching theoretical mechanism for P300, which is elicited when stimulus detection engages memory operations.

(2007) Updating P300: An Integrative Theory of P3a and P3b. has been cited by the following article: Applying Item Response Theory Methods to Improve the Measurement of Fatigue in a Clinical Trial of Rheumatoid Arthritis Patients Treated with Secukinumab* Mark Kosinski, Jakob B.previous to the appearance of a target stimulus to 800 ms. However, the baseline used for the ERP analysis was 200 ms. We included in our analysis only successful trials (defined as match stimuli).Individual segments were excluded if the absolute voltage of each channel was higher than 80 μV.All the subjects used the dominant hand to respond. References were placed at vertex by default, but were subsequently off-line re-referenced to averaged mastoids.Stimulus presentation was implemented using the STIM 1.0 software (Compumedics-Neuroscan N-back task timeline. Impedance values were kept at 5 KΩ for all electrodes.Trials were presented in 3 blocks; each block representing either the control (0- back) or WM conditions (1- and 2- back).