How do we know we are sick? When we are infected, specialized immune cells signal our brains to start a fever, make us feel miserable and cause all the other familiar symptoms of sickness, such as fatigue and the inability to concentrate on tomorrow’s exam. Work in the Goehler lab is focused on determining the exact ways through which the immune system signals the brain. The immune system functions as a sensory system tuned to detect chemical constituents of dangerous micro-organisms, and to alert sensory components of the peripheral and central nervous systems.We are analyzing this immunosensory system as a whole in the same way that other sensory systems are studied: by investigating such issues as signal transduction, receptive field characteristics, and neural pathways in the brain driven by infection. We use a combination of behavioral, pharmacological, surgical and many anatomical techniques. The latter include immunocytochemistry and neuronal tract-tracing.Our lab also studies how immune system-derived signals contribute to shifts in affective states, especially anxiety. We aim at elucidating the neurocircuitry that contributes to infection and immune activation-related anxiety by assessing neural activation that correlates with behavioral measures of anxiety in response to food-borne infectious bacteria or bacterial products.