IWD 2020: Dr Vanessa Cropley on her journey from the dairy farm to the NIH

I grew up in the country on a dairy farm. It was a simple, fairly unassuming upbringing. My parents worked very hard and struggled financially. From around the age of eight, I knew that I didn’t want to be a farmer, or a farmer’s wife. I didn’t want to stay in a small country town. I wanted more meaning; I didn’t know what that was. It was just a feeling I had.

I wasn’t the first person in my family to go to university – my mum had a diploma in kindergarten teaching and my sister was a nurse – but I was the first person in the family to do a four-year degree and the first to do a PhD.

Dr Vanessa Cropley
Dr Vanessa Cropley

When I got on the plane to America for my PhD, it was my first international flight. I was 23. I was going to one of the most renowned biomedical institutes in the world, the National Institutes of Health (NIH) in Bethesda, Maryland. I thought, ‘What have I done?’

NIH is home to some of the most brilliant scientists in the world. It was an overwhelming place. Straight from honours, I felt I didn’t belong. But I was determined to make the most of it, so I persisted and I’m glad I did. I ended up loving the experience, and on a personal level the growth was huge.

In the US, I was able to do studies that were just not possible to do in Australia. My PhD focused on PET imaging of the dopamine system in healthy people and people with Parkinson’s disease, and examined how different components of this system were important for different cognitive functions. I’m immensely proud that I had the courage to do a PhD overseas, something I didn’t think I’d ever do. For my career, having overseas experience was invaluable.

My research is broadly focused on understanding why and how schizophrenia develops. Since my undergraduate psychology days, I’ve been fascinated with the causes of ill mental health. I use PET in combination with other neuroimaging techniques, clinical and cognitive assessment and biospecimens, to interrogate the biology of illness. I use longitudinal designs to examine treatment and individual change. My research spans the spectrum of psychosis.

Infants have an innate capacity to learn any language, but lose this capacity over time. This specialisation to their native language is governed by a normal developmental process known as synaptic pruning. We don’t know what causes schizophrenia, but one of the dominant theories over the past 30 years is that something has gone wrong in this pruning.

Microglia and complement proteins are kind of like the Pacman of the immune system. They seem to regulate synaptic pruning. Complement proteins tag synapses, telling microglia to eat them. The role of complement proteins in schizophrenia has become a bit of a buzz in the field since a 2016 Nature paper, showing excessive complement activity in people with schizophrenia in genetic and post-mortem studies. This work has really revitalised the synaptic pruning hypothesis. My work focuses on the proteins that regulate brain development and see if they are abnormal in people with schizophrenia and underlie brain development processes.

I ended up at NIH because my PhD supervisor at Swinburne won an award that provided a mentor, and that was Professor Robert Innes at NIH. Robert asked my supervisor if he’d like to send someone to do some studies there. That ended up being me. Later in my career, my supervisor, Christos Pantelis encouraged me to go as Chief Investigator A on an NHMRC grant. That was a really big break. It’s so important for people in senior positions to create opportunities, because these can really kickstart one’s career.

Dr Vanessa Cropley joined the Melbourne Neuropsychiatry Centre in 2011 as an NHMRC early career fellow. She is a senior research fellow and head of the translational neurobiology group within the psychosis studies stream, which investigates neuroimaging and neurobiological markers associated with psychosis. This is an extract from her Moth talk at the Melbourne Medical School Research Symposium in December 2019.