In this course we explore the impact of interior environments on human performance and wellness. We explore the role natural daylight and perceived open space play in modulating cognitive function, and how we can engage our memories of natural environments to enhance occupant health and productivity in enclosed interiors. The course introduces a cognitive approach to design that underscores the value of perceived open space as a restorative attribute that engages our biophilic memory. Two spatial reference frames present in nature, the perceived zenith, the highest point above the observer, and the perceived horizon line, the farthest point before the observer, can be recreated in an enclosed interior space by staging an appropriate illusion to alter our perception of space. Recreating these fundamental spatial maps through an effective illusion enables a range of wellness benefits normally associated with interiors applying more traditional biophilic design principles.