The study, published today (Sunday) in Nature and carried out by researchers based at the Wolfson Institute for Biomedical Research at UCL, the MRC Laboratory for Molecular Biology in Cambridge and the University of North Carolina at Chapel Hill, examined neurons in areas of the mouse brain which are responsible for processing visual input from the eyes. The scientists achieved an important breakthrough: they succeeded in making incredibly challenging electrical and optical recordings directly from the tiny dendrites of neurons in the intact brain while the brain was processing visual information.

These recordings revealed that visual stimulation produces specific electrical signals in the dendrites – bursts of spikes – which are tuned to the properties of the visual stimulus.

The results challenge the widely held view that this kind of computation is achieved only by large numbers of neurons working together, and demonstrate how the basic components of the brain are exceptionally powerful computing devices in their own right.