// Research – Stuart Firestein

Stuart Firestein

My laboratory investigates olfaction – the sense of smell which is vital for survival. In our research, we take a wide ranging approach beginning with the chemistry of odors, their detection by the specialized cells in your nose, and the ways in which that information is processed by your brain to produce a perception of, for example, a rose from a blend of five different kinds of molecules. 

    The sense of smell is critical in detecting dangers, finding food, locating receptive mates and caring for young. This is true not just for other animals, but for humans as well. For this reason, olfaction research in our lab is relevant and necessary.  However, a more important reason for studying the olfactory system is that it serves as an especially effective model system for investigating fundamental mechanisms at work in the brain.  Most obviously, molecular recognition, the ability to detect and discriminate between a large and diverse collection of molecules is critical to every neuron in the brain which must recognize neurotransmitters, hormones, nutrients, drugs, and a host of other important molecules.  Olfactory neurons accomplish this with proteins and chemical  processes that are used by neurons throughout the brain – but it’s easier to study this in olfactory neurons.  

     Other crucial questions in neuroscience that can be profitably studied in olfactory cells are: 

  • Gene regulation– Each olfactory sensory neuron chooses only one receptor gene, indeed only one allele,  to produce all of the receptor proteins it will express.
  • Axon pathfinding– How axons find the appropriate cells to make connections. 
  • Neural Regeneration– Two of only three populations of neurons in the entire nervous system that can be regenerated in the adult brain are found in the olfactory system.
  •  Local circuit processing– From the outside world to the first area of cortex that receives olfactory input–the pyriform cortex– there are only two synapses in the direct pathway.
  • Aging in the brain– Because of lifelong regeneration of new neurons the olfactory system does not age in the same way as other sensory systems. 

 There are many other questions in olfaction not being addressed in my laboratory but in the laboratories of many other workers in the field; they include olfactory memories, pheromones and behavior, sensory psychophysics, early development of the olfactory system, genomics of olfaction, and others.