The use of methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA), also known as ecstasy, has become a growing concern worldwide. Both drugs are amphetamines, but they have different chemical structures and affinities for various types of monoamine transporters, which leads to variations in neurochemical responses and different cognitive profiles.
Previous studies have shown that both METH and MDMA can impair declarative memory and impulse control, but the present study aimed to understand the varying chronic effects of these drugs on social cognition. The researchers used a series of socio-cognitive tasks to compare individuals who used purely MDMA or were chronic METH users with a control group that had never used stimulants.
The results showed that chronic METH users had lower emotional empathy and cognition towards positive stimuli, and increased punitive and aggressive social behavior irrespective of provocation. In contrast, chronic MDMA users exhibited higher punitive behavior only when provoked in comparison to controls. However, the correlation analysis suggested that lower cognitive empathy might be linked to higher hair concentrations of both METH and MDMA, and an increase in the long-term use of MDMA was found to be linked to higher punitive behavior tendencies.
The findings suggest that chronic METH use can lead to deficits in socio-cognitive functioning, including empathy and aggression, while chronic MDMA use may be linked to increased punitive behavior only in response to provocation.
