Adenosine A2A receptors (A2AR) in the nucleus accumbens of the brain play an important role in regulating sleep and motivation, but until now, no drugs have been able to selectively modulate their function without affecting other organs or brain areas. In a recent study, a light-activated allosteric modulator of A2AR was developed and successfully used to remotely induce sleep by selective light irradiation of the nucleus accumbens in mice.