The scientists, who presented their evidence at a session of the annual Society for Neuroscience meeting in San Diego, said their discovery could also lead to a better understanding of birth defects in children born to mothers taking epilepsy medication.
Scientists have long recognized that spontaneous neural activity is needed for the normal development of the visual circuits in the brain, but how this activity is created is not well understood. UCSD researchers Marla Feller and Chih-Tien Wang detailed at the meeting their evidence that the chemical messenger adenosine controls the timing of these bursts of electrical activity. Knowing what triggers these waves of activity could make it possible to recreate them for therapeutic purposes, they said, and may shed light on disorders caused by their disruption.
"The waves of neural activity in the developing visual system have a remarkably stereotyped temporal pattern," said Feller, an assistant professor of biology who led the study. "We show that the neurotransmitter adenosine may control this pattern by altering the excitability of cells in the retina. Ultimately findings that help us understand the mechanism that generates this spontaneous activity might make it possible to recreate it later in life; for example, to coax regenerated nerve cells to reconnect appropriately after an injury."
"Another possible application of inducing patterned retinal activity in adult circuits is to set up the wiring in people who have been blinded since birth but then have some sort of surgery--like cataract removals--that gives them sight for the first time," added Feller.