Want guests to feel more at home in your home? Add a big round chair or a circular rug or ottoman.

People react more positively to, and prefer to socialize in, spaces filled with curvy forms and shapes, as opposed to rectangles, according to a new study from Oregon State University.

"Curvilinear forms create warmth," said Sibel Dazkir, a doctoral student in design and human environment, who conducted the study. "They're associated with organic forms found in nature."

In the study, more than 100 undergraduate students viewed four computer-drafted room interiors and rated how each made them feel, Dazkir said. Two of the rooms contained rounded furniture, while the other two had rectangular furniture arranged the same way.

The rooms were viewable only in gray scale, to avoid other influences, such as color and texture, Dazkir said.

Students found the all-gray rooms boring, but rated the curvilinear rooms significantly higher in pleasure and approachability (how much time they'd like to spend in the room and how sociable it made them feel).

Participants stated that the curvy rooms made them feel happier, more hopeful, comfortable and relaxed than the sharp-angled rooms, according to Dazkir.

The study is believed to be the first to assess the impact of form in interior environments, according to Marilyn Read, associate professor at OSU and chairwoman of Dazkir's thesis committee. Previous research has focused on the impact of form in the design of individual products, such as cars.

"We want people to realize that simple changes, such as adding curvilinear form, in your home or office, can make a big difference about how you feel in your environment," Read said.

The study will be published in the journal Environment and Behavior.

Kim Palmer • 612-673-4784