In our laboratory, we investigate the brain mechanisms involved in perception, cognition, and motor behavior using psychophysical methods and brain function measurement techniques, such as fMRI, EEG, and TMS. Currently, we are conducting basic research on “uncertainty,” “time,” “body,” “vehicles,” “virtual reality (VR),” and “sports,” while collaborating with industrial, medical, and educational fields. ▶Uncertainty Daily environments are highly diverse and variable, leading to uncertainty. We investigate the ways the human brain overcomes this uncertainty to achieve accurate perception, cognition, and motor behavior based on Bayesian models. Our results provide fundamental knowledge for developing techniques for sport skill training and human error prevention. ▶Time The concept of “time” encompasses diverse aspects of daily activities. Different brain regions operate on different timescales ranging from days to seconds. Our study focuses on short time intervals less than a few seconds, which are involved in daily sensorimotor behaviors, such as sports. Moreover, we investigate the retroactive effects of perception (postdiction) to explore the psychological and neural processes through which perception arises on our consciousness. ▶Body We interact with the external environment through bodily motor actions. Behind the apparent motor behavior, body perception changes flexibly. We investigate the neural mechanisms underlying the adaptability of body perception. Moreover, based on “tool-body” assimilation, we aim to apply the findings to sports, crafts, and prosthetic limbs. ▶Vehicles and VR Vehicle and VR sickness are considered transient neural malfunctions caused by conflict between sensory information based on previous experience and that of vehicles (i.e., extended bodies) or VR. We explore the predictive and adaptive mechanisms of human perception by developing techniques to reduce vehicle and VR sickness.