Unseen expressions trigger emotional reactions

Unseen facial and bodily expressions trigger fast emotional reactions

Facial reactions were recorded using electromyography, and arousal responses were measured with pupil dilatation. Passive exposure to unseen expressions evoked faster facial reactions and higher arousal compared with seen stimuli, therefore indicating that emotional contagion occurs also when the triggering stimulus cannot be consciously perceived because of cortical blindness. Furthermore, stimuli that are very different in their visual characteristics, such as facial and bodily gestures, induced highly similar expressive responses

Learning about Odors Requires Generating New Neurons

Olfactory perceptual learning requires adult neurogenesis in PNAS

Perceptual learning is required for olfactory function to adapt appropriately to changing odor environments. We here show that newborn neurons in the olfactory bulb are not only involved in, but necessary for, olfactory perceptual learning. First, the discrimination of perceptually similar odorants improves in mice after repeated exposure to the odorants. Second, this improved discrimination is accompanied by an elevated survival rate of newborn inhibitory neurons, preferentially involved in processing of the learned odor, within the olfactory bulb. Finally, blocking neurogenesis before and during the odorant exposure period prevents this learned improvement in discrimination. Olfactory perceptual learning is thus mediated by the reinforcement of functional inhibition in the olfactory bulb by adult neurogenesis.

How can we measure Galaxy distances?

Cosmology: Dark is the new black in Nature.

Rival experimental methods to determine the Universe's expansion are contending to become the fashionable face of cosmology. Fresh theoretical calculations make one of them the hot tip for next season.

It's difficult to determine distances in astronomy. Distances to galaxies have been measured using three techniques: Type 1a supernova; gravitational lensing; baryon acoustic oscillations - sound waves from the big bang.

Color Blindness Cure in Monkeys

Vision: Gene therapy in colour

Replacing a missing gene in adult colour-blind monkeys restores normal colour vision. How the new photoreceptor cells produced by this therapy lead to colour vision is a fascinating question.

The Monty Hall Problem: A New Book

Two Doors and a Goat is a review in Science Magazine of The Monty Hall Problem: The Remarkable Story of Math's Most Contentious Brain Teaser by Jason Rosenhouse.