Identify the topic sentence in the following paragraph. There are studies that show that listening to complex music helps improve the performance of the brain. Some music helps to increase the power of concentration. It would also be interesting to note that there are kinds of music that would also do the exact opposite effect to the brain. Several studies, revealed that certain music (esp. baroque and classical) such as Bach and Mozart helped students score better at tests. However relaxing sounds or silence made them score lower.