Spencer's research focuses on metabolism, stress, inflammation and satiety signalling, including early life programming of the obese brain. She has made a number of important discoveries to date, including establishing the impact of perinatal immune challenge on the immune system and neuroendocrine stress axis and identifying the long-term neuroinflammatory, cognitive, and stress effects of early life diet. This includes the pronounced and lasting effects this has on microglial cells (the brain's principal immune cells) in metabolic and cognitive brain regions. In addition, she has helped to define a novel role for the peptide ghrelin in stress. Her current project began in 2017 and is funded by the National Health and Medical Research Council (NHMRC), with additional support from the Australian Research Council and RMIT University. This work seeks to target central inflammation to combat obesity and obesity-related cognitive dysfunction, which Spencer believes could be key to abating some of the consequences of the obesity epidemic. "Solving the obesity problem is much more difficult than just asking people to stop eating and start exercising; we need to learn how to reverse the body's natural drives to stockpile energy," she explains. Her key foci are to temporally and spatially target central inflammation in childhood and also in ageing. She hypothesises that obesity induces long-term changes in the brain's immune cells, which explains a susceptibility to cognitive decline in obese individuals. Her goal is to reverse these negative effects by targeting these immune cells. Spencer is working alongside a number of invaluable collaborators. Her work on the central effects of stress and how feeding peptides interact with the stress is performed in collaboration with Associate Professor Zane Andrews at Monash University. She has been working with Associate Professor Ruth Barrientos at Ohio State University in the US to investigate the effects of ageing on microglial function and vulnerability to obesity. Additionally, Dr Luba Sominsky is a key postdoctoral fellow within her team, who is involved in most of the projects of Spencer's group.