Gestalt phenomena are often so powerful that mere demonstrations can confirm their existence, but Gestalts have proven hard to define and measure. Here we outline a theory of basic Gestalts (TBG) that defines Gestalts as emergent features (EFs). The logic relies on discovering wholes that are more discriminable than are the parts from which they are built. These wholes contain EFs that can act as basic features in human vision. As context is added to a visual stimulus, a hierarchy of EFs appears. Starting with a single dot and adding a second yields the first two potential EFs: the proximity (distance) and orientation (angle) between the two dots. A third dot introduces two more potential EFs: symmetry and linearity; a fourth dot produces surroundedness. This hierarchy may extend to collinearity, parallelism, closure, and more. We use the magnitude of Configural Superiority Effects to measure the salience of EFs on a common scale, potentially letting us compare the strengths of various grouping principles. TBG appears promising, with our initial experiments establishing and quantifying at least three basic EFs in human vision.

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Jigsaw classroom research has primarily explored racial relationships at the primary and secondary educational levels. The present study explored whether the jigsaw classroom would have an effect on students’ attitudes about their own academic abilities and practices at the university level. The present study also sought to illuminate the necessary time course for the technique. Three sections of students in a cognitive psychology course participated. One section received a full jigsaw exposure, one received a reduced jigsaw exposure, and one received no jigsaw exposure. Posttests reveal that students given the full jigsaw exposure report an increased ability to teach psychological concepts to other students compared to the control condition. Moreover, there is evidence that the jigsaw technique increases the students’ ability to communicate orally and their belief in themselves as scholars.

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A single, unique target often pops out quickly and efficiently from a field of homogenous distractors in visual search. Pop out has helped shape theories of visual attention and feature integration as well as to identify basic features in human vision. Here we report a new phenomenon, false pop out, wherein one of the homogenous distractors competes with the singleton target to pop out, perhaps by breaking an overall grouping or pattern emerging from the display. We show the effect occurs with more than 1 type of stimulus, and we discuss the implications of such a counterintuitive finding for theories of visual search.