This is a famous 1962 Pink Dove Ad by Ogilvy.
Red areas are most likely to attract attention, followed by Yellow/Orange areas, and Blue areas. Areas that have no color overlay are unlikely to attract visual attention.
The Regions Report graphically represents the likely distribution of visual attention during preattentive processing.
Any area or object that is identified as one of the first 4 predicted fixations is highly likely to be noticed at first glance, regardless of its 1, 2, 3, or 4 order.