Research in the Li Lab focuses on developing and implementing an array of novel mass spectrometry-based strategies to answer questions about the most complex and elusive set of signaling molecules, the neuropeptides, and gain new insights into the roles that peptide hormones and neurotransmitters play in the plasticity of neural circuits and behavior. While significant effort has been directed to analytical technique and method development, it is the biomedical importance of understanding the neuropeptidergic system that drives our research to continuously refine and improve the analytical capabilities to address challenging neuroscience problems.