Business Logo for Trademark

We would like a business logo (image) to go with our title. We need something that is medical in nature, with the brain, includes health, neurofeedback, biofeedback. It needs to be in color, bun can be used in b/w as well. It needs to be simple but and not too intricate as it will go on business cards as well as large signs/banners. i would like something not creepy or too gothic or too medical - but it needs credibility. We focus on brain work and modifying or testing brain behaviors. We also do meditation. The colors need to be similar to our website www.nacmed.com. We prefer rounded vs square images and soft colors. We need to own the image, have rights to reproduce it, and it is ours. It needs to be provided to us in multiple formats for print, web, etc. to submit a proposal - please mock something up that you would think would work. Provide a turn around time.