The way to receive system notifications on our Mac with OS X is through a sound emitted by the system itself (this is the default), but There is an option to receive these notices that our Mac emits 'less known' it is totally silent and can be useful in some situations.
This option is very similar to the one we have available on the iPhone with the iOS operating system 'saving distances'; it is based on a warning by means of a flash or 'blink' that occurs on our monitor when we receive a notification or warning. As I say, it can be useful in some situations but it is always good that we know of its existence and how to activate or deactivate this option that the Apple OS X operating system offers us, let's see how to do it.
We can carry out a test before changing the warning system in case we do not like it or we simply want to see it act before using it, for this we have to access the menu as always and click on System preferences. select Accessibility and click on Audio in the left column:
To test the alerts in the form of flash, we just have to click on Test Screen Flicker:
Once tested, if you think it can be useful to silently receive alerts from your Mac, you just have to check the box 'Trigger the screen flickering when issuing an alert'and every time we receive a notice of the type that an application from the' dock jumps' the screen will flash to warn us. Now it is up to each one to use or not this warning system.
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