Do you know of any documentation that states dementia and Alzheimer patients benefit from a lighted room vs sitting in a room with no lights?

I am the POA of a friend (91) with dementia. Because of a fall and broken femur, thus surgery and anesthesia, his dementia has declined tremendously. I had to move him from Assisted living to skilled care in the same facility. The facility overall is one of the best in the area, but on the Alzheimer's floor in skilled care they keep all the lights dimmed in the common area and hallways. Thus it's very gloomy and depressing. I call it an above ground cemetery. I think they want to keep them sedated by sitting in an area with no lights on.

So I am looking for any links you can send me that I can show the facility that what they are doing is not good for the residents. I don't want my friend being in that environment but if I am not here I can't do anything about it.