Modulating the difficulty of a visual oddball-like task and P3m amplitude.

ABSTRACT: It is often necessary to modulate the difficulty of an experimental task without changing physical stimulus characteristics that are known to modulate event-related potentials. Here, we developed a new, oddball-like visual discrimination task with varying levels of difficulty despite using almost identical visual stimuli. Gabor patches of one orientation served as frequent standard stimuli with 75% probability. Gabor patches with a slightly different orientation served as infrequent target stimuli (25% probability). Analyzing the behavioral outcomes revealed a successful modulation of task difficulty, i.e. the hard condition revealed decreased d' values and longer reaction times for standard stimuli. In addition, we recorded MEG and computed event-related fields in response to the stimuli.

SUBMITTER: Boetzel C 

PROVIDER: S-EPMC10794184 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature