What is dha from most fish oil? and isnt it true that it is needed by your brain more that epa

O3: There are reports stating dha is more prevalent in the brain and more important, primarily due to the findings of reduced brain inflammatory chemicals, which are usually linked to some neurodegenerative and inflammatory conditions. This did not report that epa was not as important for other reasons. Nevertheless, it is thought that both are anti-inflammatory and positive for brain function.