Replicability and Heterogeneity of Awake Unrestrained Canine fMRI Responses

Abstract

Previously, we demonstrated the possibility of fMRI in two awake and unrestrained dogs. Here, we determined the replicability and heterogeneity of these results in an additional 11 dogs for a total of 13 subjects. Based on an anatomically placed region-of-interest, we compared the caudate response to a hand signal indicating the imminent availability of a food reward to a hand signal indicating no reward. 8 of 13 dogs had a positive differential caudate response to the signal indicating reward. The mean differential caudate response was 0.09%, which was similar to a comparable human study. These results show that canine fMRI is reliable and can be done with minimal stress to the dogs.

Decoding Human Emotional Faces in the Dog’s Brain

“…Other fMRI studies with dogs have also shown activation of this structure because it has been related to reward 29 and to familiarity of scents 30 . Our group also found greater caudate activity related to neutral human faces than to objects 10 .…”

Special issue: The “dominance” debate and improved behavioral measures—Articles from the 2014 CSF/FSF

“…I think it is far more plausible and logical that species that have and use identifiable patterns in signaling in a non-random manner to reflect and manage asymmetries in knowledge and relationships, have the capacity, given the evolution of the mammalian brain, to understand social organization and what risks shifts in it pose to them. These conclusions are supported by elegant, emergent imaging work (Berns et al, 2013(Berns et al, , 2015Cook et al, 2014). The unit of evolution is the individual so one should have the expectation that recognizing, understanding and participating in management of behavioral asymmetries in a labile environment would be a skill upon which selection would work in social animals.…”

Functional Magnetic Resonance Imaging of the Domestic Dog: Research, Methodology, and Conceptual Issues

“…Berns, Brooks, and Spivak (2013) followed their initial 2012 study of fMRI with dogs with an assessment of the replicability of their methodology. Further, the authors sought to potentially reduce signal variability of caudate responses to the instrumental reward task with additional experimental improvements.…”

“…These findings were consistent with Berns et al (2012); however, substantial signal variability was found across subjects for overall caudate activation. Berns et al (2013) discuss several potential reasons for this variability between subjects, including greater human attachment in service and therapy dogs, the inherent noise of imaging data, the difficult balance between imaging repetition and efficacy of the task, mislocation of regions of interest, and individual motivational differences. Interestingly, the authors note that when the dog fMRI data collected from the instrumental reward task is compared to that of humans, it may indeed be less variable than human caudate activity.…”

“…When training dogs to lie still for fMRI, researchers have used a variety of techniques including chaining (e.g., Berns, Brooks, & Spivak, 2013), target stick (e.g., Jia, Pustovyy, et al, 2014), and model-rival (e.g., Andics, Gácsi, Faragó, Kis, & Miklósi, 2014) methods. In most cases, training builds incrementally from basic contingencies outside the scanner room (e.g., head on chin rest in mock coil, touching nose to target) to inside the scanner room (e.g., prone position on scanner bed) to inside the scanner bore (e.g., head still in coil for scan).…”