Workspaces can enhance the creativity of the designers that occupy them. Here, we review experimental studies of creative spaces to identify constructs that mediate (explain) the relationship between physical spaces and creative performance. Through a literature review of 8 journal articles comprising 13 experiments, we identify 14 constructs involving cognitive, affective and physiological components. Knowledge of these mediators can help researchers to formulate hypotheses, select control variables, and develop conceptual models and theories of creative spaces in design.