Outlook in 2016

From their earliest beginnings, cities have brought both benefits and risks to the health of their inhabitants. Although some of the hazards have been banished, others remain — and new ones have emerged. By Stephanie Pain

Deprivation leads to stress, and stress to bad health. A park, and the science behind it, aims to break that chain.

Transporting people around the cities of the future is a public-policy challenge, but it's also an opportunity to improve the health of urban populations.

Cities are complex environments. Planning interventions that borrow principles from theoretical physics could help to improve peoples' lives.

Water is a necessity for any city, but too much of it can threaten lives and infrastructure. As climate change looms, new approaches can help to turn a threat into a resource.

Exposure to nature makes people happy and could cut mental-health inequalities between the rich and poor.

The growth of slums in the developing world's rapidly expanding cities is creating new opportunities for infectious disease to flourish and spread.

As mind sports becomes the new frontier for doping concerns, research is exploring whether users really get any value from 'smart drugs'.

Social ties go hand-in-hand with cognitive health. Now researchers are trying to determine why engaging with others helps to keep the brain healthy.

Future generations may have less to fear from cognitive decline thanks to microscopic insights into the ageing brain, and interventions from unexpected quarters.

Before data were so abundant, computer models of the brain were simple. Information is now much more plentiful — but some argue that models should remain uncomplicated.

Conflicting results are expected in a young field, but what do you do when even the meta-analyses do not agree?

Stress can have a negative influence on the human brain, but increasingly it is the ability to withstand severe stress that is the focus of research.

Consumption of animals helped hominins to grow bigger brains. But in a world rich with food, how necessary is meat?

Thoughtful use of ubiquitous technology can improve mental ability more than drugs and devices, say Nicholas S. Fitz and Peter B. Reiner.

As neuroscientists explore the therapeutic prospects of brain stimulation, the amateur community are hoping the technology will enhance their mental faculties or well-being.