Various tricks can be used to create attraction. One of the simplest ways is for a character on-screen to look towards a specific point, often with rather dramatic emotional effect. It's rather like if you're standing around with your friends and suddenly they all look towards something; you want to know what they're looking at, so without thinking, you look too. The animated character stands in for real people, and evokes the same instinctive response; without thinking, you turn to look at what the animated character is looking at, attracting your attention to the desired point.
Similar to this, the effect of anticipation can create attraction, when a moving object creates tension in the moment of buildup before the climax of a motion. This weighty pause tells us subconsciously that something is coming, so it hones our attention on the focal point of the anticipated motion. When the motion carries through, it can also draw our attention in a different direction and create attraction towards the end point of the motion.
Other ways of creating attraction are through rapid movement. This can involve something zipping across an otherwise still scene, creating attraction to that particular object or character - but also, if you wish, creating attraction to its destination. Sudden dramatic movements from characters, such as jerking or waving the arms, also create attraction. For something simpler, things like rapidly changing colors or blinking lights can also attract the eye to a point in a scene.
Not just rapid movement creates attraction, though. Erratic movement can, as well; if something is moving in a fashion different from what we commonly expect, the oddity will make us zero in on it unerringly. This effect is often seen in animated scenes that depict a plane or some other object crashing down towards characters positioned in the foreground. While the character actions in the foreground seem like they should be our focus for the scene, in the background we'll see the plane looping and lurching around drunkenly in a way that isn't natural, draws the eye, and not only creates attraction, but creates anticipation and foreshadowing from the inherent knowledge that we see the plane coming and the characters don't.
More subtle attraction effects can use zoom, focus, perspective, and depth of field to attract the eye to a specific point by honing in on it, clarifying it, or emphasizing its distance from other objects. Even using different colors can create attraction. Imagine you're watching a black and white cartoon, and suddenly there's a bright red flower in the middle of a field of gray grass. You'll instantly look at the red flower, attracted to it by its color.
There are dozens more unique ways to create attraction; basically anything that disrupts a viewer's attention and draws it to the desired point is something that creates attraction, no matter how you choose to do it. Attraction in an animated scene is like a child jumping up and down and screaming for attention, willing to do anything to make sure you notice - only if you do it right, it's much, much less annoying.
