Faster MRI scan can track groups of neurons as they fire

Today we learn about recycling mixed plastics into useful chemicals, hear about a faster MRI scan that can capture brains activity in mice and consider our pick of the five best science books this week.

Mixed plastics are difficult to recycle, but a new process shows how it can be done.

Mixed plastics recycled into useful chemicals

Researchers have used chemistry and bacteria to break down mixtures of plastics, usually a headache to recycle, into useful chemical ingredients. The process works with soft food-packaging plastic, the strong, lightweight plastic used to make drink bottles, and even polystyrene, which includes styrofoam. But scaling it up will be a challenge. Selling the molecules that the bacteria produce will be difficult because demand for those products is much smaller than the quantity of waste plastics.

Reference: Science paper

Faster MRI captures brain activity in mice

A twist on functional magnetic resonance imaging (fMRI) enables it to map neuronal activity in mice so fast that it can track groups of neurons as they fire. Researchers improved the fMRI time sensitivity by tweaking the software and by applying frequent, repetitive stimulation to the animals that they were testing, making it possible to observe faster brain activity. The biggest question now is whether this method can be applied to human fMRI scans. People might not respond to repetitive stimulation the same way every time — they might get bored — and complex thought processes might be too long-lived and wide-ranging to track in this way.

Reference: Science paper