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.
Dose of Science: Is MDMA Neurotoxic for Human Users?
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.
Can Margin of Exposure Be Used as an Objective Measure of Drug Harm?
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.
