The hysteresis in the perception has been observed in many perceptual experiments, but little is known about the underlying dynamical mechanism. We simulate a visual discrimination task, as an example of hysteresis in the perception, using a spiking neuron network and the corresponding slow dynamic system. The hysteresis in visual perception has been reproduced in our simulation. We find that hysteresis is influenced by the change speed of the external stimuli and the excitatory recurrent interaction inside the selective neuron pool. The slow dynamic system reveals the dynamical mechanism underlying the hysteresis: emerging from the lag between the response of neural system and the fast change external stimuli when the slow dynamic system has a single steady state; emerging from the multiple steady states regardless of the change speed of the external stimuli. In particularly, the multiplicity of the steady state of the slow dynamic system comes from the codimension three swallowtail catastrophe which exhibits two interacting cusp catastrophes.