The study of 5-hydroxytryptamine (5-HT) systems has benefited from the identification, classification and cloning of multiple 5-HT receptors (5-HT1 to 5-HT7). Increasing evidence suggests that 5-HT pathways, reuptake site/transporter complex and 5-HT receptors represent a strategic distribution for learning and memory. A key question still remaining is whether 5-HT markers (e.g., receptors) are directly or indirectly contributing to the physiological and pharmacological basis of memory and its pathogenesis or, rather, if they represent protective or adaptable mechanisms. Certainly, Alzheimerś disease (AD) is a very complex neuropsychiatric disorder, where memory becomes progressively dysfunctional resulting in amnesia and dementia, whereas forgetting is a physiological phenomenon occurring all the time as adaptive mechanism. As dysfunctional memory occurs in several neuropsychiatric disorders, including schizophrenia, stroke, post-traumatic stress disorder. Hence, the aim of this call is collect recent and important findings related to information about serotonin and memory or 5-HT and learning or 5-HT and memory or serotonin and learning.