Iain Stewart is Professor of Geoscience Communication at Plymouth University. What that really means is that he is a geologist that spends much of his time writing and talking about our planet - how it works, its volatile history and what all that means for those living on it.

His work has involved not only looking back millions of years into our past, but trying to work out what we can learn about our future from the inter-relationships between people, places and the environment in our geological history.

Recorded on one of Edinburgh's seven dormant volcanoes, in this episode of Brainwaves Iain Stewart explains how a better understanding of geoscience is far more than just the geology under our feet and how geologists around the world seem to be one lifelong fieldtrip where ever they go.

Waking in his hotel room Eric Sinclair was paralysed down his left side, his mouth dry and his tongue heavy. He called for help, but all he could do was make a small squeaking sound. He knew very little about stroke until that day, but he was one of the 15,000 people a year who suffer a stroke.

Stroke is the third commonest cause of death in Scotland and the most common cause of severe physical disability among adults. Of 100 people going into hospital alive, over a quarter won't survive the first year. Of those who do, many will be permanently disabled. Stroke doesn't just affect the elderly, it is unpredictable and can affect all ages.

So what is it like to actually experience a stroke? What is happening inside the brain and body of a stroke patient as this attack on the brain unfolds and where has science got to in terms of explaining stroke, its prevention and the long path to recovery?

The selfie - just an exercise in self-obsessed narcissism or potential store for scientific research? A picture can tell far more than 1,000 words. A selfie can define you, it can locate you, it can help analyse air quality, they can track cultures and fashions and during the Rio Olympic Games a simple photograph between to Korean athletes crossed a political divide.

The selfie is the artistic expression du jour and, love them or hate them, they're not going anywhere fast. But the selfie isn't a new thing, portraiture has been seen in art for centuries. So what is our fascination with the representation of our self and why do we want to share it with the world?

In this episode of Brainwaves, Pennie Latin explores the science of the selfie, what they can tell us about ourselves and discovers how your selfies are helping scientists learn more about the world around us.

What are strong memories made of? Why do we remember what we remember and which memories last, quite literally, a lifetime while others just fade away? In this Brainwaves special Pennie Latin investigates how our brain makes and retrieves memories; explores how memory changes over time and why we seem to remember certain stages of our lives and particular events more sharply than others and considers the memories which remain most precious as we age.

Part of the BBC Scotland Memories and Conversations - New Approaches to Dementia season.

They say that power is seductive and that giving it up can be incredibly hard to do. But that is what David Erdal did when he turned his family run business into an employee owned company.

He says the consequences for him were embarrassing, emotional, hugely psychologically complex but overall satisfying. He went from being the boss to being just the same as everyone else in the company.

In this episode of Brainwaves, Pennie Latin looks at the role of rank and hierarchy in our society. She asks how much does it actually matter to us and what can we learn about ourselves by looking at rank and hierarchy in some of our nearest evolutionary neighbours, chimpanzees.

Born in Jamaica in 1940 Geoff Palmer arrived in the UK aged 14 years and 11 months with little formal education. Declared educationally sub-normal it was his ability on the cricket field that got him into a grammar school and started his scientific education that would eventually bring him to Heriot-Watt University and become the UK's first professor of Brewing and Distilling and Scotland's first black professor.

His research into the grains and cereals, in particular the malting process changed the brewing industry and saved it millions of pounds.

In the lecture theatre he took great delight in telling his students that they should be tasting beer as well as learning about how to make it.

Now retired, it is with a sense of great pride that he can look at craft beers from across the world and taste the hard work of his former students.

Surf n' Turf is a new pilot project on the Orkney island of Eday that aims to harness excess renewably generated electricity; store it as hydrogen and then make it available again as electricity to charge the inter-island ferries berthed overnight, in the soon to be developed hydrogen port at Kirkwall.

The idea of using hydrogen as a source of power isn't new. Commercial scale electrolysis has been around for a couple of hundred years. Today there are already hydrogen cars and buses on our roads, prototype ships at sea and plans on paper for introducing it into aircraft, all powered by the most abundant element in the universe.

However it is widely known that one of the biggest problems with renewable power is the intermittency of it, yet our demand for energy is constant. In this episode of Brainwaves, Pennie Latin explores whether hydrogen might overcome that intermittent problem and be the power source we all turn to in future.

With access to our personal healthcare data, Professor Andrew Morris's research into diabetes informatics has already led to a reduction of diabetes related amputations by 50%. He aspires to see a year in his lifetime when there are no diabetes related amputations in Scotland.

Our personal data is hugely valuable. Not just to us but to scientists, researchers and healthcare providers around the world. With access to vast amounts of information about us and our health, scientists like Andrew are able to examine population wide healthcare issues.

By turning that vast amount of information into knowledge says Andrew you can improve healthcare provision across the entire country and make it more efficient at the same time.

But with access to that information comes responsibility and a need for trust. In this episode of Brainwaves Pennie Latin meets Professor Andrew Morris, Director of The Farr Institute, Scotland to look at how data science and informatics are improving the health of Scotland.

How many times have you turned on Radio Scotland only to hear that the Kessock, Skye and Dornoch bridges are closed to high sided vehicles and that there are speed restrictions on the Forth Road Bridge? The Scottish weather has a dramatic impact on Scotland's bridges, but if the scientists and engineers have got their sums right, that is about to change.

The Queensferry Crossing will be the longest three-tower, cable-stayed bridge in the world, it will be the highest bridge in the UK and with height comes wind. But the "weatherproofing" design of this bridge means that there shouldn't be any closures and restrictions due to weather.

Due to open in 2016 during Scotland's year of Innovation, architecture and design, The Queensferry Crossing is combination of all three of these elements.

In this episode of Brainwaves Pennie Latin meets the bridge designers and engineers to discover the science that is going into Scotland's latest feat of engineering.

In 2009 to a wave of great acclaim in the scientific community a new role was created in Europe - the post of Chief Scientific Adviser to the European Commission, reporting directly to the President of the EC. The role was given to a prominent Scottish biochemist - the then Chief Scientific Adviser to the Scottish Government, Professor (now Dame) Anne Glover.

However, it was a post that only lasted for 3 years.

A long time ambassador of women in science, Professor Dame Anne Glover talks to Pennie Latin about her passion for communicating science to the mass audience, be they politicians, policy makers or prospective students.

A keen sailor, who's ideal first date would be at one of Scotland's 5 interactive science centres she is now the Vice Principal of External Affairs at Aberdeen University, charged with communicating the University's work across the globe.