For more information, see Busquets-Garcia et al., Neuron 99/6, http://www.cell.com/neuron/fulltext/S0896-6273(18)30687-1.
Cannabinoid CB1 receptors signaling in the hippocampus, a brain structure involved in memory processes, underlines the mammalian ability to associate randomly encountered stimuli, allowing future inferred memories and possibly explaining seemingly ungrounded responses toward certain cues. The authors thank Franck Burglen and Marie Lods for the movie preparation and illustration.