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Cocaine addiction is often modeled in experimental paradigms where rodents learn to self-administer (SA) the drug. However, the extent to which these models replicate the functional alterations observed in clinical neuroimaging studies of cocaine addiction remains unknown. We used magnetic resonance imaging (MRI) to assess basal and evoked brain function in rats subjected to a prolonged, extended-access cocaine SA scheme. Specifically, we measured basal cerebral blood volume (bCBV), an established correlate of basal metabolism, and assessed the reactivity of the dopaminergic system by mapping the pharmacological MRI (phMRI) response evoked by the dopamine-releaser amphetamine. Cocaine-exposed subjects exhibited reduced bCBV in fronto-cortical areas, nucleus accumbens, ventral hippocampus, and thalamus. The cocaine group also showed an attenuated functional response to amphetamine in ventrostriatal areas, an effect that was significantly correlated with total cocaine intake. An inverse relationship between bCBV in the reticular thalamus and the frontal response elicited by amphetamine was found in control subjects but not in the cocaine group, suggesting that the inhibitory interplay within this attentional circuit may be compromised by the drug. Importantly, histopathological analysis did not reveal significant alterations of the microvascular bed in the brain of cocaine-exposed subjects, suggesting that the imaging findings cannot be merely ascribed to cocaine-induced vascular damage. These results document that chronic, extended-access cocaine SA in the rat produces focal fronto-cortical and striatal alterations that serve as plausible neurobiological substrate for the behavioral expression of compulsive drug intake in laboratory animals.

Anatomical waxworks lay at the centre of a composite world of social interaction in mid-18th-century Bologna. Sponsored by Pope Benedict XIV and included among Grand Tour attractions, they earned fame and authority for wax-modellers such as Anna Morandi, Giovanni Manzolini and Ercole Lelli. By dissecting bodies, making waxwork models of them and demonstrating their anatomical collections, these artificers became protagonists of the world of anatomy. Offering representations of the inner body some thought more faithful than the real thing, their collections gave expression to a new set of relations between the role of artefacts in the production and communication of knowledge, the emergence of new apparatuses for viewing and investigating the human body, the legacy of codified visual conventions and the authenticating power of natural spectacle.