Successful batters often report that the baseball looked “huge” just before they hit a home run. This effect, dubbed action-specific perception, has been noted for years in all kinds of physical activities.

Yet questions remain about why the illusion happens. Some experts say it is a consequence of imagining the action before you make a move. Others suspect that knowing you nailed it might conjure a larger target in your memory. But a new study in Acta Psychologica suggests neither process alone is enough. Something else is needed: visual attention.

Researchers from Amsterdam and Hong Kong asked three groups of students to putt golf balls at a target about five feet away. After first checking out the target, one group had to putt the ball under a curtain obscuring the view. Another group putted between two corks en route to the target. The third group simply putted at the target without distraction. In all three cases, individuals got feedback about where their balls ended up. They then estimated the target’s size by drawing it on a computer screen.

As expected, successful individuals in the straightforward putting experiment described a bigger target. Not so for the putters who could not see the target or give it their full attention.

The results challenge the theory that action-specific perception arises from imagining your motions before performing them, explains co-author John van der Kamp of the Free University Amsterdam, because such visualization was possible for all the participants. Similarly, simply knowing the putt hit the pin was not enough.

Visual attention to the target, therefore, is key. But scientists still do not know whether seeing a bigger target contributes to—or results from—success. One thing is clear: what we see is often not an accurate reflection of the world around us. Our senses are influenced by our attention and experiences.