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Access Type

Open Access Thesis

Document Type


Degree Program

Neuroscience & Behavior

Degree Type

Master of Science (M.S.)

Year Degree Awarded


Month Degree Awarded



Previous studies completed with humans have revealed insight into the effects of anxiety on attention tasks such the dot-probe task, but there is little information about such effects on non-human primates. This study aimed to assess whether anxiety or anxious behaviors would impact rhesus macaque performance on a three stimuli paradigm similar to the dot-probe task. Utilizing images of conspecifics (strong threat, mild threat, and neutral), eight monkeys were video recorded completing a task that required them to slide two doors, which held these images, to the side to obtain a treat. We hypothesized that behavioral phenotype (high or low anxiety) would affect attention on this modified dot-probe task. Additionally, we predicted that time spent looking at mildly threatening stimuli would be positively correlated with high levels of anxious behaviors (e.g., scratching, yawning, pacing, self-biting) and cortisol concentrations over a four month period. We also predicted that a higher percentage of the mildly threating stimuli as a first choice would be positively correlated with high levels of anxious behaviors and cortisol concentrations. However, anxious behaviors and cortisol concentrations did not affect performance on this task. Interestingly, a sex difference was found for the mild threat stimuli, with females taking significantly more time to complete the task when presented with the mild stimuli (p = 0.01), and also looking at the mild stimuli longer than males (p = 0.03). These data suggest that males and females interpret ambiguous facial expressions differently, possibly indicating the significance of attention in female dominance hierarchies in macaque social groups.


First Advisor

Melinda A Novak