Researchers at the University of Pittsburgh have discovered how Ritalin affects brain activity, revealing a deeper understanding of how groups of brain cells influence attention and identifying new possibilities for the stimulant.
methylphenidate, also known as Ritalin, is used by one out of five adults in the United States to improve attention and focus in individuals with attention-deficit/hyperactivity disorder or ADHD. There are also many more people on the market that use these drugs off-label. While the safety and effectiveness of these drugs is well understood, there is still a lot to be learned.
According to senior study authorMarlene Cohen, who works in the Kenneth P. Dietrich School of Arts and Sciences, these drugs are beneficial to the activity of groups of neurons. But basic scientists like us have been looking at what groups of neurons can unsettle about behavior and cognition, and therefore understanding what these drugs do to them might be beneficial for.
Amy Nish, a Pitt postdoctoral researcher, emphasized the relationship between how well animals performed on a visual task and a specific measurement of neurons in the visual cortex, how likely they are to fire off independently of one another, rather than being synched up.
In the current study, they discovered that animals that had taken methylphenidate performed better on a visual task of attention; that the improvement occurred exactly when the same metric of neuron activity shifted. The researchers, led by Ni, published their research in the journal Proceedings of the National Academy of Sciences on April 25.
Some of the study findings were collected from whats already known about the drug. Three animals took methylphenidate or a placebo on alternate days for two weeks of testing. On days when they took the drug, they spent longer on the task and performed better at it, but only when the required task occurred in a spot they were already paying attention to.
According to Cohen, researchers target very small groups of neurons with electricity or light. We absolutely didnt take these drugs, mixed them in fruit juice, and gave them to animals. It surprised me that a very general manipulation would have a very specific behavioral effect.
Along with learning more about how the drug works, such experiments allow researchers to gain a better understanding of how neurons function when the brain is in different states, such as when a person has taken a medication or when they havent, allowing researchers to develop more complete and useful models of how brain cells and behavior are linked.
Cohen claims that this approach hasn''t received widespread attention, partly because of a lack of ways to finance research on how drugs alter the activity of neurons. That makes it difficult to look for crossover therapies, i.e., new therapies for those who have already been on the market.
Recent research in the laboratory reveals some of these potential crossovers. Ni has found similarities between neural patterns linked to attention and certain types of learning, implying that therapy for disorders involving one might be beneficial for the other.
Cohen claims that these stimulants may be effective in dealing with a variety of topics, from cognitive changes associated with normal ageing to Alzheimers disease and others. Despite its potential relevance, it is still a well-informed hunch, which the lab intends to pursue in future studies.
For the time being, this study is still a significant first step in a line of research Cohen intends to see more of: connecting the neural foundations of our behavior and how medications affect it.
It''s one test case, and I think there''s still a lot to be done, according to the author. I hope that individuals will recognize that these techniques are effective.