Date of Award


Document Type


Degree Name

Master of Science (MS)


Department of Psychology

First Advisor

Jeffrey Wagman


Perceivers are sensitive to the boundaries at which they must transition from one mode of performing a given behavior to another. As in other self-organizing systems, such transitions occur at a critical value of a parameter with continuous changes in that parameter. In general, behavioral transitions occur at larger values when that parameter increases than when it decreases (positive hysteresis), and perceptual transitions (for a behavior to be performed by one’s self) occur at larger values when that parameter decreases than when it increases (negative hysteresis). We investigated whether this pattern also occurs in perceptual transitions for a behavior to be performed by another person. In our first experiment, we investigated perceptual transitions in a reaching task for the self and for another person: participants reported when they (or another person) would need to transition from reaching for an object with their arm to reaching for an object with a hand-held implement. As predicted, perceptual transitions exhibited negative hysteresis. In a second experiment, we investigated behavioral transitions in the same reaching task: participants attempted to reach for an object with either their arm or the implement. Contrary to our predictions, behavioral transitions did not exhibit positive hysteresis. The results are discussed in terms of a dynamical systems perspective on perception of affordances both for oneself and for another person.


Imported from ProQuest Dayer_ilstu_0092N_11268.pdf


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