Department or Program



Object substitution masking (OSM) is a type of visual masking in which a briefly displayed target is surrounded by a four-dot mask. When the dots disappear after the target, participants typically cannot accurately recall the target. The current study seeks to address the ongoing debate in the literature about the extent to which targets are processed in OSM. Studies show that individuals with social anxiety have an attentional bias for processing threat stimuli. Using this bias, Experiment 1 seeks to explore whether socially anxious participants are better than their non-anxious peers in detecting social threat words but not control words, which would suggest that words are processed to a semantic level. Results are insignificant and do not support this hypothesis. However, all participants were significantly better at detection when the target disappeared before the mask. Upon noting the visual disparity between the target and mask in Experiment 1, Experiment 2 was designed to test whether this recovery effect depends on target-mask incongruence. Results support this hypothesis, but fail to clarify whether this occurs because of shape- or object-level differences. To clarify this, Experiment 3 used two different objects shown at two different orientations for the target and mask. Results show recovery when the target and mask are different objects and masking when the target and mask are the same object. Overall, the current study suggests that targets are semantically in OSM, but only when they are objects, not words. Furthermore, this study supports the presence of top-down influences on perception.

Level of Access

Restricted: Embargoed [Open Access After Expiration]

First Advisor

Kahan, Todd

Date of Graduation


Degree Name

Bachelor of Arts

Number of Pages


Components of Thesis

1 pdf file


Available to all on Tuesday, March 28, 2023