If you are like a lot of people in the world, not recently.
The unspoken truth is that if your brush is not clean. Dr. Gerba, a microbiologist of Arizona University found that hair brushes are one of the worst breeding grounds for bacteria, more than a plughole! If that is not enough to get cleaning routine going, dirt, oil and product build up is being put back into your freshly cleansed curls. Seems a little counter intuitive to us.
A good rule of thumb is to clean your brushes every one to two weeks. If you see product build up on your brush, it is definitely time to clean it.
How to clean your brushes
Submerge your brushes into hot water and add a clarifying shampoo, castile soap or washing up liquid. Leave to soak for 30 mins to an hour. Work out any grime with a toothbrush (not the same one you use for your teeth!) or other hairbrushes you are cleaning concurrently cleaning to work out the grime. Leave to dry on a towel in a cool place.