Effects Of Mental Arithmetic Task On Object Substitution Masking

In the “Object substitution masking”, mask and target are shown at the same timeafter a short period of time, mask continues to render for a period of time, whichcauses the visibility of the target reduced. Most of the previous researches study effectobtained from the number of target set, without investigate dual-task and target setsimultaneously. For this reason, we designed3experiments, examines effects ofobject substitution masking by the mental arithmetic tasks and a single target; effectsof object substitution masking by targets and mental arithmetic task; effects of objectsubstitution masking by different degree of difficulty of mental arithmetic task andtargets.In experiment1, we add a mental arithmetic task before the object recognitiontasks, in which target is single. The experimental results show that the rate of correctreports were ceiling effects, the addition of mental arithmetic task does not have asignificant impact on object substitution masking. In the experiment2, the target setof object recognition task is expand to eight and the target stimuli will be any of themrandomly,the time interval between mental arithmetic task and object recognition taskis divided into two levels (100ms,500ms).The experimental results show that both themental arithmetic task and the time interval have a significant effect of objectsubstitution masking. Object substitution masking effect is stronger in the case ofdual-tasks, the time of two task intervals is shorter, the stronger masking effect is. InExperiment3, the mental arithmetic task difficulty is divided into three levels,twotask time interval is500ms, the other conditions the same with the experiment2. Theresults show that the mental arithmetic task difficulty have a significant effect of theobject substitution masking, that is, the mental arithmetic task difficulty is greater,object substitution masking effect is stronger.