Asymmetry in Psychoactive Research: A Bibliometric Study on 15 Psychoactive Drugs

Introduction

Trading and consuming psychoactive drugs is regulated by national laws and international conventions, which differentiate legal substances such as alcohol and caffeine from controlled substances like LSD or cocaine. Lebrero-Tatay and colleagues describe how these regulatory frameworks, notably post-1961 conventions and national acts, have imposed licences, institutional restrictions, supply barriers and funding difficulties that hinder research on controlled drugs. The authors argue these barriers create an asymmetry in scientific attention across different psychoactive substances, and note prior bibliometric work has identified regional and topic biases but has not fully integrated historical and socio-political context when interpreting publication trends. This study set out to compare publication trends for 15 psychoactive substances from 1960 to 2018, with the aim of testing whether stricter legal control is associated with unstable or declining growth in the research literature. The investigators hypothesised that (a) literature on highly restricted drugs would deviate from an exponential growth curve and show periods of stagnation or decline, and (b) less- or non-restricted drugs would follow a more typical exponential growth. They also anticipated regional differences in productivity related to socio-political factors.