In this edition of Dose of Science, we are going to take a look at a meta-analysis of using LSD therapy to treat alcoholism [1]. ‘Meta-analysis’ means that the study pools together data derived from multiple trials and re-analyses the combined evidence. The advantage is that the combined evidence reduces the statistical uncertainties, and permits more robust conclusions than any of the individual studies in isolation.

The ‘cognitive impairment theory’ proposes that cannabis causes cognitive decline. The hypothesis has gained some support from a 2012 study, but a recent paper with twin participants strongly argued against the theory. Both studies agree on the association between smoking and cognitive decline. Where they disagree is whether the relationship is causal or merely correlation. In this Dose of Science we take a close look at the question. 

MDMA’s neurotoxicity is the topic of this and many future editions of Dose of Science. The question is not whether MDMA is neurotoxic in an absolute sense, but rather, what is the extent of the damage at various dosing regimens. Stephen Kish’s study [1] from 2010 aims to clarify the picture by employing a range of neuroimaging techniques and cognitive tests on a large sample while controlling for many potential confounding factors. 

IFLScience, one of Facebook’s biggest science advocacy page recently headlined a study that “New Study Finds Marijuana Safer Than Alcohol Or Tobacco” [1]. While this is a catchy title, the paper only partially supports the statement. In this edition of Dose of Science we are going to take a close look at the original research article [1] to examine whether weed is really safer than alcohol.