The Role of Alpha and Consciousness

I just caught an interesting post on Mind Update (a side blog for the Transparent Corporation) titled:

Brain Rhythms and Consciousness, and how Alpha may play a new role
The article discusses how certain brainwave frequencies, like Gamma and Alpha, affect levels of consciousness.  Gamma frequencies have been typically associated with a more awakened state, higher levels of consciousness, and have been shown to be exhibited by experienced meditators.
Alpha frequencies, on the other hard, are associated with a quiet and idle mind.  Activities like day dreaming, or closing your eyes will produce Alpha frequencies.
A new study suggests that Alpha does play a crucial role in higher levels of consciousness and cognitive performance.