Evaluation of Reaction Time During Asynchronous Oddball Paradigm

Reaction time, defined as the time between the presentation of a stimulus and the response to that stimulus, is widely used for evaluating cognitive functions. Prolonged reaction time is associated with delayed neuronal activity. The type, complexity and length of the stimulus affect reaction time. This study aimed to investigate whether there were differences in reaction time in the auditory and visual oddball paradigms, which are frequently used in cognitive studies and to examine the effect of prolonged task duration on reaction time. The study was conducted on 19 male healthy university students aged between 18-23 years.  A dual-task with an oddball paradigm was applied to the participants. The paradigm consisted of 160 stimuli including 32 auditory targets, 32 visual targets and 96 standard stimuli. The participants were asked to press buttons as soon as they perceive the target stimuli. Reaction time of participants to each target was calculated automatically. The reaction time for both tasks compared statistically and it was observed that visual reaction time was significantly longer than auditory reaction time (p= 0,042). In addition, to examine the effect of task duration on reaction time, the first ten and last ten target stimuli were investigated in both tasks. It was observed that the reaction time was prolonged and errors increased towards the end of the task (p<0,01). As a result, this study demonstrated that auditory reaction time was shorter than visual reaction time, and revealed that the type and length of the stimulus should be considered in reaction time studies.