Meagan Longoria describes the basics of the Gestalt school of thought:
Gestalt principles can help us highlight patterns and reduce noise in data visualization. They can also help us create a visual hierarchy and employ symmetry in our designs for a more pleasing user experience.
Some Gestalt principles are very similar to our understanding of preattentive attributes. This is demonstrated in the set of 3 charts below.
Meagan gives a good overview of the concepts and uses a Power BI example to apply them. There’s some really good advice in here.