We are very conscious at DFT about Dementia Friendly environments and how such things as posters are presented.
Sometimes dementia interferes with our sensory perceptions. E.g a black doormat can look like a black hole with no bottom. A white doorhandle on a white door is impossible to find. Stairs are difficult if there is no clear edge to each step. So a contrasting strip across the edge of each step makes it easier to negotiate the steps.
Too busy makes for confusion for person with dementia. Clear concise spacing with contrasting colours is much better.
Some of our members participated in a virtual reality study of the inside of a house to ascertain all the hazards for someone with dementia and in a wheelchair. It was fascinating.
Stirling University Dementia Services Dementia Centre https://www.dementia.stir.ac.uk/ runs courses for Dementia Care professionals and 3rd Sector charitable and voluntary group groups about the how to make life better in hundreds of person centred ways to suit individual needs.