Systems and methods for generating and rendering one or more images, such as in an animated image sequence, of the virtual multi-dimensional object on a display screen for testing a person's susceptibility to a Depth Inversion Illusion (“DII”). The methods also include collecting first information indicating the person's perceptual response to the DII； adjusting a strength of the DII by manipulating a texture that is mapped onto the virtual multi-dimensional object； collecting second information indicating the person's perceptual response to the DII； using the first and second information to determine differences between the person's perceptual responses to the DII and reference perception responses of a group of control subjects to the DII； and analyzing the differences to determine a severity of the person's mental illness or to assess therapeutic efficacy.
