“…Positron emission tomography (PET) shows that 5-HT 4 receptors (5-HT 4 R) are particularly abundant in brain regions involved in affective processing and memory, including the hippocampus, amygdala, and frontal cortex (Eglen, Wong, Dumuis, & Bockaert, 1995;Lucas, 2009). Our research group has recently published a high-resolution in vivo atlas of the serotonin system in humans, including the 5-HT 4 R (Beliveau & Ganz, 2017; downloadable maps are available at this website: https://nru.dk/FS5ht-atlas). Experimental studies also show that pharmacological stimulation of 5HT 4 R improves memory consolidation (Bockaert, Claeysen, Compan, & Dumuis, 2008;King, Marsden, & Fone, 2008), possibly through increased release of acetylcholine (Bockaert, Claeysen, Compan, & Dumuis, 2004).…”