Ceiling height affects creativity

Research by Joan Meyers-Levy and Rui (Juliet) Zhu  found that, depending on the
situation, ceiling height will benefit or impair consumer responses.

"When a person is in
a space with a 10-foot ceiling, they will tend to think more freely,
more abstractly," said Meyers-Levy. "They might process more abstract
connections between objects in a room, whereas a person in a room with
an 8-foot ceiling will be more likely to focus on specifics."

This information is take from the University of Minnesota's press release.

The findings suggest to me that the human brain works metaphorically – although this article by Chris Morris offers an alternative explanation, that people just have more room to make big pictures in their minds when there is a high ceiling.