Cognitive representations of multilevel buildings: two- or three-dimensional?

Previous research suggests that conventional multilevel buildings are cognitively represented as a stack of horizontal planes, whereas an atrium-shaped architecture which allows easy visual access to other levels is represented as a volume. The present study investigated whether easy physical access to other levels also promotes a volumetric representation. Participants were examined in a virtual 3D grid maze in which they could access higher and lower levels at each intersection. During a learning phase, they were transported through the maze across twelve intersection, each featuring a unique object. In the subsequent test phase, they were asked to indicate the location of these objects on a schematic drawing of the maze. Response accuracy in the test phase was similar when the twelve visited objects were arranged in a horizontal plane and when they were laid out in a volume. In accordance with earlier reasoning, this suggests that easy physical access to other levels indeed can facilitate a volumetric cognitive representation of multilevel architectures. Additional findings suggest that this representation emerged gradually rather than abruptly like a sudden insight, and that transport through the maze without left and right turns facilitated the internal representation, probably by reducing the associated cognitive load.