Study out of the Nature Reviews Neuralscience shows that scientists at UCLA Brain Research Institute find that the Omega-3's fight mental disorders such as Dementia, Depression and Schizophrenia and also can help in boosting memory etc..
They support Neurons by supporting their Synaptic Plasticity and also the Expressiion of DNA that enhances Neurons in the Brain especially the compound DHA which is found mainly in Salmon.
More info and studies in the Science Daily article for those interested.
Scientists Learn How Food Affects The Brain: Omega 3 Especially Important