While the results regarding the effects of PRL-8-53 was published in 1978, and is considered perhaps the best verbal memory boosting agent by nootropic community, it has remained relatively obscure in spite of the increased proportion of aging population with memory impairment in one hand and, possibly, increased need to study in advanced age in developed countries. Frankly, there is not much research information about PRL-8-53 other than the original study [1] that found remarkably increased verbal recall, especially in the subjects with initially poorer memory without acute side effects. Higher doses motor function and have spasmolytic properties. The mechanism of action is unknown but PRL-8-53 seems to counteract monoamine depleting drug reserpine, yet without possessing stimulant properties. The mechanisms may be associated with potentiating effects of acetylcholine and dopamine while counteracting serotonin. Considering rather promising results of the preliminary study, the paucity of further research seems outright disturbing in the light of the current challenges that present themselves to the population of today.
References:
https://www.ncbi.nlm.nih.gov/pubmed/418433