Transcranial Magnetic Stimulation Fireworks

Charles Bonnet Syndrome

Melanie Shee

I took part on research into Charles Bonnet Syndrome  with Dr Kat da Silva Morgan at Newcastle Univeristy. As part of this  Transcranial Magnetic Stimulation (or TMS for short). A very brief magnetic pulse was applied to the back of my head.  This is designed to test what is referred  to as the ‘resting excitability’ of the visual part of your brain in the occipital lobe (which is located at the back of your head).

The magnetic pulse causes a brief increase in the activity in that part of the brain and is what causes people to see lights or fireworks. The lower the intensity of the stimulation that prompts these flashes, the more ‘excitable’ the visual part of your brain is.

The team hypothesised that this may be something that contributes to CBS (Charles Bonnet Syndrome) and in their study we did indeed find a link between a more ‘excitable visual cortex’ and more intense or severe visual hallucinations in CBS. We also found that people with CBS tended to have a more excitable visual cortex than people with sight loss who didn’t experience visual hallucinations.

That evening I awoke and experienced a never ending spectacle of fireworks going off in my room for about 20 minutes. It was spectacular and only stopped when I put the light on.