Brain Sciences


Meet the expert: Professor Sanjay M Sisodiya

Sanjay Sisodiya is Professor of Neurology at the UCL Queen Square Institute of Neurology whose research focuses on complex epilepsy.

Photo of Sanjay, smiling at the camera.

We caught up with Professor Sisodiya to ask him about his research, what excites him most about his work and what advice he would give his younger self.

What attracted you to investigate the area of epilepsy and climate change and why is it important?

I did a project at school, during the last century, about using plants to clean polluted water, and another in which I learnt that lichen are great indicators of air quality. My concern for the environment stayed with me, but I did not link that private occupation with my professional life until people with severe, often genetic, epilepsies and their families started to tell me how bad their conditions became during recent heatwaves.

That moment of connection was a revelation, a realisation that I had some agency in the challenge of climate change, through my clinical and research work in epilepsy.

People with some rare genetic epilepsies have seizures that can be precipitated by high ambient temperatures, rapid temperature changes, or fevers. Many more people with (the more common) epilepsies will have more seizures when their sleep is disrupted. Individual resilience to change may be impaired in epilepsy.

Climate change will affect many aspects of life and it seems likely that people with neurological conditions, including epilepsy, will be among the first to feel the effects. This led me to start EpilepsyClimateChange and look in more detail at what might happen. It’s all the more important because we may learn from this what will happen eventually to the brain in people without neurological diseases, eventually encompassing us all. 

How does climate change impact the brain and nervous system?

Excitability in the brain, and in other organs like the eye, ear, peripheral nervous system, skin, heart, depends on complex interplay between various proteins and processes, many of which show temperature-dependence.

Human thermoregulation is tight and powerful, but not insuperable. We already know that despite thermoregulation, ambient temperatures, especially when extreme, can affect neurological function, as we see in the many temperature-sensitive epilepsies, many nerve and muscle disorders and temperature-related aggravation of aspects of multiple sclerosis, for example.

Moreover, climate change will have effects beyond temperature and temperature extremes alone: humidity will rise in certain regions, making higher temperatures even less tolerable; the ranges of neuroinfection-bearing biting arthropods will spread and naïve populations will be exposed to infections; higher nocturnal temperatures disrupt sleep, and sleep quality is critical in many neurological conditions; worsening air pollution has direct consequences on stroke risk; climate change-related extreme events such as floods will disrupt supply chains. The list goes on.

The pandemic has shown us in a compressed timescale how global challenges do happen, how lives can change dramatically, how shelves can become bare. Climate change will have a bigger impact still, and it seems unlikely that the brain and nervous system will not be affected.

Can you tell us about your current research in this area?

We are exploring the impact of climate change at many levels, while at the same time taking action where we can, given that there are things we can already do to reduce our own impact, even before we uncover the details of the impacts of climate change on epilepsy and other neurological conditions.

At the level of my own research, we are looking at the impact of climate change on the molecular biology of the epilepsies, on seizure and neurophysiological patterns, on the effect of the built environment, on treatments, on risk of premature mortality and on the carbon costs of epilepsy services.

Across UCL, there are many important initiatives on action and research, including a Faculty-wide consortium addressing these questions across neurological diseases, including important involvement from the Centre for Behaviour Change and the Climate Action Unit. Through EpilepsyClimateChange, we hope to further promote research internationally, raise awareness and take action.

What aspect of your work most excites you and why?

Understanding the basis of a problem, and seeing a way to help. Finding something new that makes a difference.

There are so many problems to be tackled in epilepsy, my first area of interest, and many of these problems have remained unsolved for years. Sometimes a different perspective, a novel approach, or connecting apparently disparate dots brings new insight.

I’d rather not have to think about working on climate change – it would be much better if we were not putting the future of our species at huge risk – but given that it’s happening, it seems important to work in this area too. And in this area, I am learning so much, and making new connections: that’s always exciting, and sometimes surprisingly throws light on old questions!

How do you think researchers can make a difference to the challenge of climate change?

We are, potentially, slowly emerging from the pandemic, though of course no one can really know, and we can only hope that there are no huge nasty surprises yet to come.

I have no expertise in this area, but it does seem that we needed our brains to see a way through the pandemic: people changed their behaviour; models helped us think in sensible ways about how best to respond; the generation of vaccines in such a short time-line has been hugely important.

Research was at the heart of the entire response. Climate change is no different: we will need research, and our brains, to manage. Even if all carbon emissions stopped tomorrow, there are embedded changes already under way which we will need to address, and research will be – is – at the heart of the response to climate change as it was for the pandemic.

We can all make a difference – through our professional research and through our actions both at work and in our lives more generally. When we all act to the same end, we can make a huge difference.

What’s the best advice you would give your younger self?

Pursue what you find interesting and think is important. Follow your heart. Don’t be discouraged if it seems off the beaten track. Experiment, not only in the purely scientific sense.

I have often found that people who have had unorthodox backgrounds to their eventual journeys in science benefit from the wider perspective they will hopefully have acquired, and bring fresh and interesting perspectives: I admire their courage, and I wish I had done the same.

Work with people in other fields: there is real excitement to be found at the interfaces in life! Practically, combining clinical work with basic science is a challenge, and sometimes may make you feel you are giving neither enough: but on the best days, it can be a thrilling mix, bringing science directly to benefit people with serious conditions: humbling, immensely worthwhile and deeply rewarding.

And if that is that path you choose, then I would say try to listen to what people are telling you about their condition, and explore that if you can. It can be difficult to do, but those deep insights from personal experience often give clues to real understanding of disease processes, and of what is important to people with the condition.