The ISI plays a large role in the phi phenomenon (Wertheimer) since the illusion of motion is directly due to the length of the interval between stimuli.
When the ISI is shorter, for example between two flashing lines alternating back and forth, we perceive the change in stimuli to be movement.
[2] The distinction between the two types of conditioning is of importance because the difference in the interstimulus interval (ISI) can have major effects on learning.
[3] The changes in the gap of time can be minuscule, from tens of milliseconds to several seconds long, and the effects it will have will still be important.
[4] Sensory and motor tasks are among the elements that can be enhanced or hindered based on timing, like speech processing, which can be influenced by "the ability to discriminate the interval and duration of sounds.