Inspired by the mechanism of fixational eye movement and dynamics of vertebrate's cortex, we propose an active tremor operation (ATO) approach based on dual probes adaptive model (DPAM), and find a resonance phenomena between DPAM and ATO, which is enhanced and suppressed when DPAM and ATO are in-phase and anti-phase, respectively. Based on the observations, we propose a novelty directional selectivity adaptive motion detector. The experimental results show that the motion detector with directional selectivity can detect effectively the edge with specific motion direction, and adapt to the change of illumination and clutter background. The temporal statistic results of motion detection can obviously reflect the motion features of visual object action.