Geometry of Object Storage and Recognition in Human Memory

Objects in the environment have a large variety of appearances due to 3D to 2D mapping, occlusion, self-occlusion and the relative position and orientation between the object and the observer. How does the brain store and recognize objects? There are three main ways we investigated: Structural Descriptions, Perspective Views, and Canonical Orientation. Using the mental rotation paradigm, to investigate how objects are stored and recognized in human memory. The mental rotation paradigm consists of a linear relationship between rotation angle of an object and a subject’s reaction time to analyze the object. We investigate if there exists canonical storage in the human brain and if so, what is its relation to figural symmetry and elongation axis. We tested if the reaction time profile can be expressed as a linear combination of these two variables. In these preliminary data, the model appears to capture data relatively well with the possible exception of the 90-degree orientation angles. Preliminary data supports the canonical orientation hypothesis with symmetry playing an important role in determining the canonical orientation.