This paper discusses hemodynamics when subject repeats the attentional control task. Generally, repetition is related to learning effects and leads to his or her habituation. In that case, brain activity in prefrontal area decays, in comparison with the single task. However, if the task itself gives large load to working memory, reaction in brain may not change. Our team notes this point and evaluates the hemodynamics of the subject using near-infrared spectroscopy. We apply multivariable estimated models which show properties of each stage, given by hierarchical decomposition method.