Skip to main content
Figure 1 | BMC Neurology

Figure 1

From: Cluster analysis of behavioural and event-related potentials during a contingent negative variation paradigm in remitting-relapsing and benign forms of multiple sclerosis

Figure 1

Experimental paradigm. A modified version of the central-cue Posner's paradigm. 75% standard stimuli, 25% target trials. Five blocks with 200 trials each were presented. All stimuli last for 300 milliseconds (ms). The presentation of stimuli was random (left or the right side). Target and Standards were presented at 2.46 degrees to the left or the right of the central fixation point. Cues could point towards the position where the stimulus appears (valid trials, 80%) or the opposite side (invalid trials, 20%). The subject's task was to indicate the appearance of the target stimulus in the left or right visual field by pressing the left button or right button. Therefore, left valid, left invalid, right valid and right invalid trials appeared both for standard and target trials.

Back to article page

BMC Neurology

ISSN: 1471-2377

Contact us