Does perception have a "frame rate"? Are the objects of visual perception processes divisible into individual, still frames, like video is? If so:


Are the perceptions from different senses synced to the same frequency?
Are these "stills" instances of perceiving motionlessness?
Is the perception of motion based on pattern recognition between the stills?
There is no true frame rate of the eyes, but there are limitations.  The brain uses blurring to simulate continuity.  Films are shot at 24 frames per second; if you go too much lower than that, the film will seem choppy.  This is because the motion blurring process is too fast and it finishes "blurring" before the frame changes, so you just see choppy frames.  If it's a bit faster, suddenly the blurring occurs in a time frame on the order of the frame changing and it looks smooth. 

Similarly, audio doesn't really have a frame rate, but there are limitations to what frequencies the sensory can transmit into neural code. ~(20 Hz - 20kHz).

So you do see some kind of frame rate for perception being plausible, and it turns out that higher-level perception rates are not fixed, but depends on the modality of the perceptions themselves:


  Recanzone has recently demonstrated that the perceived rate at which people judge a light to be flickering on and off can also be modulated by the rate at which a concurrent stream of auditory stimuli are presented


Even if there weren't a frame rate, due to differences in processing times between the two systems, there would still be a synchronization process required:


  Light travels through air far more rapidly than sound: 300,000,000 versus 330 metres per second. Differences in arrival time also occur for events that occur much closer to us, and yet we are rarely aware of them. Part of the reason for this is that the mechanical transduction of sound waves at the ear takes less time than that required for the chemical transduction of light at the retina. These physical and biophysical differences in the arrival time of light and sound cancel each other out when stimuli are approximately 10 metres from us, at the so-called ‘horizon of simultaneity’. Given most audiovisual events are not perceived at this ‘optimal’ distance, however, psychologists, neuroscientists and even philosophers have long puzzled over why the perception of multisensory synchrony should be such a pervasive aspect of our everyday phenomenology.


Spence, Charles, and Sarah Squire. Multisensory integration: maintaining the perception of synchrony. Current Biology 13.13 (2003): R519-R521.