Drug-sensitive Reward in Crayfish: Exploring the Neural Basis of Addiction with Automated Learning Paradigms

Systemic infusions into the pericardial cavity (A) or drug delivery in close proximity to the supraesophageal ganglion (B) accessory lobes (enlarged in C) produced various behaviors related to exploration (viz., locomotion, antennal movements, rearing up along the arena sides). Psychostimulants trigger active exploration-like behaviors in crayfish, most likely via neural sites within the head ganglion. The accessory lobes are components of higher brain structures in the crayfish brain and potential neural structures that facilitate the vulnerability of the system to a wide range of mammalian drugs of abuse. It is associated with higher-order decision making in the environment, for instance, choosing a specific tactile or visual stimulus associated with reward.