Methods and systems are disclosed for quantitatively assessing mental states and/or characteristics of an individual. Specific mental states and/or characteristics, or properties thereof may, in some embodiments, be associated with one or more stimuli. In some embodiments, such stimuli may be administered to an individual, whereupon the individual's responses are usable to determine one or more aspects of the individual's mental affect. Some of the disclosed methods and systems are based at least in part on computerized and computer-associated devices.