Mice that receive neuron transplants are better at forgetting fearful memories than those without transplants.

Yong-Chun Yu at Fudan University in Shanghai, China, and his colleagues studied mice that had learned a fearful memory and were then trained to forget it. After this 'extinction' training, fear memories often come back spontaneously with time or in response to a stimulus. But the team found that this later recurrence was reduced when embryonic neurons that make a neurotransmitter called GABA were transplanted into the animals' brains two weeks before the extinction training.

The neurons were transplanted into the amygdala, a brain region associated with fear, and the findings suggest that the cells may have returned it to a more pliable, juvenile state. This could increase the effectiveness of fear-extinction training, the authors suggest.

Neuron http://doi.org/bvp3 (2016)