Sleep quality naturally declines during aging. For example, both sleep duration and sleep consolidation both deteriorate. (Less consolidated sleep is more fragmented, with shorter mean sleep bout duration). Moreover, impaired sleep quality is a sensitive prodromal sign of future cognitive decline and Alzheimer’s disease (AD)
Most drugs used for nootropic purposes are far different from drugs that are used recreationally. However, a handful of substances with “no accepted medical use” in countries like the United States hold great promise as cognitive enhancers. Case in point: psychedelics.