Will you wake up the next day and be able to hear, speak to and see spirits? Nope. BUT, this helps open you up so that you can develop the ability to do so. This goes along with chakra balancing and meditating as well. For some a single casting works and for others several castings are needed and we won't know until we begin walking this path.
You have to be open to the possibilities and be open to growing spiritually with this spell.