Your mind is not only the basis of all activity, it is an activity in itself.
And as with all activities you can start and stop it whenever you like. Some of us feel like the mind just runs on its own and can’t stop it….this may be the case if you are constantly running on autopilot and not training your mind.
But you can stop the activity and focus on something completely different any time you choose. In fact the more you change focus to one area or one consistent image, feeling, emotion, the more the pattern of activity is remembered.