Functional magnetic resonance imaging in the awake rabbit: a system for stimulus presentation and response detection...

We describe a reliable system to control the timing of multiple stimuli and to detect eyeblink responses during functional magnetic resonance imaging (fMRI). The methods for stimulus delivery and timing, eyeblink detection, and response quantification are described in detail. We are using these methods in awake rabbits to study eyeblink conditioning (EBC) as a model paradigm for the study of learning and memory. Examples of conditioned eyeblinks in the awake rabbit during fMRI are presented for validation of our techniques. The results indicate that eyeblinks can be reliably recorded during fMRI, and that neither the stimulus delivery nor the response detection interferes with each other or affect the quality of the images. The combined fMRI/behavioral techniques should be useful for examining the entire brain simultaneously during the associative learning of a conditioned reflex in an animal model system.