ADHD drugs do not improve cognition in healthy college students -- ScienceDaily
Results of the new study, published last month in the journal Pharmacy, show that the standard 30 mg dose of Adderall did improve attention and focus -- a typical result from a stimulant -- but that effect failed to translate to better performance on a battery of neurocognitive tasks that measured short-term memory, reading comprehension and fluency.
Weyandt has a theory about why working memory would be adversely affected by the medication. Brain scan research shows that a person with ADHD often has less neural activity in the regions of the brain that control executive function -- working memory, attention, self-control. For people with ADHD, Adderall and similar medications increase activity in those regions and appear to normalize functioning. "If your brain is functioning normally in those regions, the medication is unlikely to have a positive effect on cognition and my actually impair cognition. In other words, you need to have a deficit to benefit from the medicine," Weyandt said.
Participants in the study also reported their perceived effects of the drug and its impact on their emotions, with students reporting significant elevation of their mood when taking Adderall.
In contrast to the small, mixed effects on cognition, the drug had much larger effects on mood and bodily responses, increasing positive mood, emotional ratings of the drug effect, heart rate and blood pressure. "These are classic effects of psychostimulants," said White. "The fact that we see these effects on positive emotion and cardiovascular activity, in the same individuals for whom cognitive effects were small or negative in direction, is important. It indicates that the cognitive and the emotional impact of these drugs are separate. How you feel under the drug does not necessarily mean that there is an improvement in cognition; there can be a decrease, as seen here in young adults without ADHD."