“Light was produced by two 3 W LEDs (main light spectrum peak at blue light 465 nm and a secondary peak at 550 nm) and delivered via 5 meters long polycarbonate colourless fiber optic light guides connected to ear-plugs in the subject’s ears while inside the scanner.”
Findings from the study :
“…suggest that the brain possesses photosensitive properties, which will have interesting implications for the modulation of brain function and understanding the basic physiology of the brain.”
But, the authors add :
“The mechanism for the phototransduction of the brain tissue remains to be discovered and we are currently investigating it in more depth.”
 “ Some of the authors have conflicts of interests with a company, Valkee Ltd., that develops and sells devices for bright light stimulation via ear-canal. Authors’ connections with Valkee Ltd. are: Nissilä and Aunio are company founders. Nissilä, Aunio, Takala and Timonen are share-holders (varying from major to minor). Nissilä, Aunio and live-in partner of Starck are employed by Valkee Ltd. Valkee Ltd. did not have a role in the decision to submit the paper for publication.”
 The company, Valkee, has recently received a US patent for their invention ‘Portable Ear Light Device’ and also have a European patent pending for a Device and method for altering dopamine level from which the illustration above is taken.
 Many thanks to John Hoyland’s Feedback column in New Scientist, 10 May 2013 ‘Light up your Brain’ for drawing attention to the Valkee ear light.
BONUS : (unrelated, except via wordplay) ‘Me ears are alight’