Mouse scroll wheel and monitor brightness

The scroll wheel on my mouse is clickable. If I click on the scroll wheel and roll it at the same time, it decreases the brightness on the monitor. Clicking and scrolling the opposite direction does not increase the brightness, so I have to stop whatever I'm doing, go into system preferences, and increase the brightness.

This is very annoying! How can I change it so that clicking and scrolling the scroll wheel simultaneously does not control the monitor's brightness? Or at least so that I can both increase and decrease the brightness with the scroll wheel so that if I accidentally decrease the brightness then I can increase it quick and easy.