Have you noticed how the smell of delicious food has a very different impact on you whether you are hungry or full? A key function of the brain is to evaluate incoming sensory information in the context of immediate internal needs. Under different motivational states—such as hunger—the same sensory input is perceived and acted upon differently. The neural mechanism behind this modulation of information interpretation is still unknown. The lab of James Jeanne aims to understand how behavioral flexibility arises from neural circuit flexibility at the level of synaptic function. A Kavli Innovative Award (2019, James Jeanne and John Carlson) allowed the team to shed light on the anatomical basis of synaptic function. Taking advantage of the emergence of whole-brain connectomics of electron microscopy (EM), the Jeanne lab explored reconstructed maps of synapses in Drosophila melanogaster and noted that many connected neurons have a single synapse, whereas others can have hundreds. To examine the functional significance of this diversity, the lab aimed to link Drosophila anatomy (i.e., connectomics via electron microscopy) with physiology (a measure of synapse strength). This work revealed a linear correlation between the number of synapses and the connection weight, concluding that much of the connection strength can be explained by EM data. Understanding the relationship between connectivity and activity will enable more biologically relevant functional predictions from the connectome.
Catalyzing Impact through Focused Research Funding: James Jeanne
September 06, 2024