Here's a summary of, "How interior design choices can boost your mental and physical health" from New Scientist, 13 Apr 2022:

Studies exploring the effects of clutter on our environment have shown that maintaining an organized home can be beneficial. For example, there's a notable connection between procrastination and clutter. Additionally, research indicates that a cluttered home environment is associated with higher cortisol levels throughout the day. It might not be the clutter itself causing the stress, but the worry about maintaining a neat appearance. Therefore, creating some visual order in your living space can be advantageous. Something as simple as arranging your books by color can bring more organization to a room, suggests Lee.

It's also beneficial to consider ways to enhance your environment so you feel more in control. In one study at an insurance company in Wisconsin, employees were given the ability to adjust the lighting and ventilation at their workstations, which led to a noticeable increase in productivity. This might be due to improved physical comfort, but other studies indicate that merely having the perception of control over our surroundings can improve our mood, even if the physical environment doesn't change much.

While considering these changes, remember to honor your individuality. Although environmental psychology provides strategies to reduce stress, instill discipline, and boost productivity, exceptions always exist. If having an oversized, shiny Harley-Davidson motorcycle on display in your living room brings you joy, it's perfectly fine to break the rules occasionally (just remember to return the rulebook to its spot on your color-coordinated shelf).

Adjust Your Lighting to Enhance Thinking

Lighting can subtly influence our mental state, often without us realizing it. Research has shown that the type of lighting in our environment can significantly affect our thinking processes. For instance, Anna Steidle and Lioba Werth at the University of Hohenheim in Germany found that bright lighting (around 1500 lux) promotes greater self-awareness, leading to more reflective thinking.

On the other hand, dimmer lighting tends to make us less self-conscious, fostering a more experimental mindset that can be beneficial for creative problem-solving. In one study, participants in dimly lit settings were better at solving the candle problem, where they had to figure out how to fix and light a candle on a wall without letting the wax drip on the floor, using only a box of matches and thumbtacks. The solution involved emptying the thumbtack box, placing the candle inside, and then attaching the box to the wall with a thumbtack.