Examining the relationship between Canis lupus familiaris and stress : An fMRI study

• Main Author: Petersen, Julie Elizabeth
• Format: Text
• Language: English
• Published: Drexel University 2021
• Subjects: Psychology; FOS Psychology; Clinical psychology; Dogs; Stress, Psychological; Canis lupus
• Online Access: https://dx.doi.org/10.17918/etd-6808; https://ResearchDiscovery.drexel.edu/discovery/fulldisplay/alma991014632842804721/01DRXU_INST:ResearchRepository

Stress has detrimental effects on a person's physical and mental well-being. The domestic dog (Canis lupus familiaris) has demonstrated a unique capability for mediating stress, an ability that remains largely unexplained. The current study examined the relationship of dogs and stress mediation to explain possible mechanisms of action. This study hypothesizes the mechanism is not reliant upon one's perception of the dog, but rather upon one's perception of the situation and surrounding people within which the dog exists, that effects his or her stress level, even if a previous relationship with the dog does not exist. This is contrary to literature suggesting that a person's relationship with the dog mediates change in stress levels. Instead, the dog has an indirect effect by altering a person's perception of a situation through the dog's presence. The presence of a dog makes others appear friendlier and more trustworthy to the person, and, consequently, these people are less likely to be sources of stress for the principle subject. According to the hypothesized mechanism of chagne, stress-related neural activation is greater when a stressful task is administered by a human alone in comparison to when that same task is administered by a human with a dog. To test this hypothesis, twenty-one healthy, neurologically normal participants underwent functional Magnetic Resonance Imaging (fMRI) scanning, during which the Paced Auditory Serial Addition Test (PASAT) was administered via video by a human alone or a human with a dog. Results demonstrated clear evidence that the PASAT is a stressful attentional vigilance task. Additional activation during the human alone condition indicated task adherence and selfconsciousness, while activation during the human with dog condition involved regions associated with emotion and anxiety. Contrasting the two task conditions suggested deactivation of eye-tracking processes in the human with dog condition. Regressions with a measure of stress did not provide evidence that the presence of a dog removed elements of stress or anxiety during the task. Region of interest (ROI) analyses focusing on brain regions implicated in stress, namely the amygdala, insula, anterior cingulate cortex (ACC), caudate nucleus, posterior-medial frontal gyrus (pDFG), and hippocampus, ndid not yield significant differences between the human with a dog and human alone condition. Findings from this study do not replicate prior research demonstrating dogs as mediators of stress. Robust activation during the PASAT indicate its usefulness as a stressful attentional vigilance task.