Dr. Geoff Bunn presents a journey through 5000 years of our understanding of the most complex thing in the known universe: the brain, in this major ten-part BBC Radio 4 series.

In Episode 3, 'The Origin of Common Sense', the focus is on Ancient Rome with Galen's 'animal spirits' gently inflating the ventricles and making thought possible, and on how early Christian scholarship placed the soul in the brain's ventricles. But with the Dark Ages, it was Islamic scholars who continued to explore the brain: Al Razi studied apoplexy or stroke, while Ibn Sina proposed that thoughts travelled through the brain in a predictable sequence and identified the 'common sense' in the front ventricle.

The series is entirely written and presented by Dr Geoff Bunn of Manchester Metropolitan University, with actors Paul Bhattacharjee and Jonathan Forbes providing the voices of those who have written about the brain from Ancient Egypt to the present day, and actor Hattie Morahan giving the Anatomy Lesson which establishes the part of the brain to be highlighted in each episode – in this instance the ventricles. The original, atmospheric score is supplied by composer, Barney Quinton. Producer: Marya Burgess.