Osaka: Noradrenaline is a neuromodulator secreted in the brain depending on
behavioral context and physiological states of animal, influencing a
wide range of physiological functions by modulating brain activity. It
may be best known as a hormone to regulate heart rate and blood flow,
and many drugs, such as well-known beta blockers, target its effects. It
also modulates the visual system. "Noradrenaline administration modulates the primary visual cortex
(V1)", says Osaka University Associate Professor Satoshi Shimegi. "It
changes the spatial sensitivity of this region."