A study published in the journal Psychopharmacology has found that the increase in motivation people experience from methamphetamine is separate from the drug’s ability to produce a euphoric high. The findings suggest that these two common effects of stimulant drugs likely involve different underlying biological processes in the brain. This research indicates that a person might become more willing to work hard without necessarily feeling a greater sense of pleasure or well-being. The researchers conducted the new study to clarify how stimulants affect human motivation and personal feelings. They intended to understand if the pleasurable high people experience while taking these drugs is the primary reason they become more willing to work for rewards. By separating these effects, the team aimed to gain insight into how drugs could potentially be used to treat motivation-related issues without causing addictive euphoria. Another reason for the study was to investigate how individual differences in personality or brain chemistry change how a person responds to a stimulant. Scientists wanted to see if people who are naturally less motivated benefit …