Spring cleaning is a ritual in many households—for good reasons. During Fall and Winter, we spend hour after hour confined to our homes, often doing things that make our homes spaces that amp up our stress levels. After Spring cleaning, they’re more relaxing places to spend time with family and friends
We continually accumulate stuff and dealing with it is part of Spring cleaning. Stuff isn't trash, it's torn out magazine articles set aside to be re-read later, gifts that haven't quite made their way to their final resting places, and cozy nests created to fight off the Winter chill—in a word, it's clutter.
Clutter is mentally exhausting. In our less developed prehistory, we needed to continually survey our environment, to make sure that nothing that found us appetizing was approaching. It's easier to review a less cluttered environment; danger stands out more clearly. That survey behavior from long ago is probably at least one of the reasons that we prefer less complex wallpapers today. Each time we review a space—and we still do scan the environment each time we enter a new one—our eyes focus on each item there. Clutter makes it take longer to complete an "environmental sweep."
Clutter is undesirable for another major reason. We use the design of spaces we control and the objects we place there to communicate to ourselves and others who we feel we are—at least on our good days. We are very good at reading our own environments and those of others - research has shown, for example, that we can pretty accurately assess a person through a quick review of places they control. We can even estimate how well a space could communicate who we are - that's why we can take a couple of steps into a perspective home and decide if it's the space for us.
Excess objects and disorder can cloud the message sent by a space. Not clearly presenting ourselves through spaces we control causes stress. Imagine that the spaces we control are topiary plants - they always need to be trimmed so people can determine the story we're telling.
Spend a few hours de-cluttering—the mental health rewards you'll reap will make it time well spent.