Researchers at McGill University have discovered that feedback pathways enable sensory neurons to respond to weak sensory input in order to lead to perception.
Published in PLoS Biology, their study shows that feedback pathways, which are seen ubiquitously across sensory systems and account for 90-95% of input onto sensory neurons, are necessary to generate neural responses and perception of weak sensory input that would otherwise not be detected by the organism. These results thus reveal an elegant mechanism by which the brain processes sensory information, which is critical for understanding brain function at large.
Read the full text article in PLOS biology:
Metzen MG, Huang CG, Chacron MJ. Descending pathways generate perception of and neural responses to weak sensory input. PLoS Biol. 2018 Jun 25;16(6):e2005239. doi: 10.1371/journal.pbio.2005239.