Cholinergic Precursors Compared: Alpha-GPC and Citicoline in the Literature
Human plasma after oral citicoline carries uridine, not cytidine, which is the reverse of the rat. The two cholinergic precursors reach the same cycle by different chemistry.
AMPA Receptor Modulation: What Ampakines Do at the Molecular Level
A 2002 structure of GluR2 showed that stabilising the dimer interface reduces desensitisation. Everything ampakines are said to do at the molecular level follows from that one interface.
The Racetams and Their Missing Mechanism: Fifty Years Without a Consensus
A 1994 review of 407 papers reported no accepted mechanism for the racetams. A 2010 review still called it an enigma, and the crystal structures published in between separated the class rather than unifying it.
Modafinil and the Dopamine Transporter: What Imaging Studies Showed
A 1994 paper reported low-affinity binding at the dopamine uptake site; PET imaging in 2009 put human transporter occupancy between 39 and 54 percent. The mechanism debate did not end there.
Bromantane’s Dual Profile: Actoprotector Research from the Soviet Era
Forty-five of the fifty-six PubMed records naming this compound in the title carry no DOI, and six carry no abstract at all. The evidence base is measurable before it is readable.
The Evidence Base for Cognition Research Compounds: A Critical Guide
A molecule can be active in a cell-free assay, produce a clean result in mice, and show nothing in a randomised trial without any contradiction. This hub maps the evidence hierarchy and the failure modes at each level.