The Maimon lab aims to link the electrical activity of neurons and the biochemical action of molecules to their computational roles in animal behavior. The lab has a particular interest in understanding how central brain structures, distant from the sensory and motor periphery, govern navigational decisions.
It has long been widely accepted that explaining animal behavior requires more than just defining stimulus–response relationships. Rather, cognitive operations—such as spatial attention, reward expectation, sensory prediction, and the construction of internal spatial maps—have a fundamental role in modifying these relationships. Yet the conceptual frameworks for thinking about such internal processes, and our understanding of their neural implementation, remain in their infancy.
Work in the Maimon lab is inspired by the observation that insects, despite having tiny brains, perform sophisticated internal computations, like those responsible for bees executing a waggle dance, or for desert ants navigating home after a journey for food. By seeking comprehensive descriptions of how small nervous systems perform quantitatively accurate internal calculations, the Maimon lab aims to provide new inspiration on how to better understand cognitive processes in larger brains.
The lab studies the genetically tractable fruit fly, Drosophila melanogaster, and has pioneered one of the primary approaches it uses. The technique involves monitoring or perturbing activity in neuronal circuits in flies as they perform flight or walking behaviors, glued to a tiny platform.
In recent work, the Maimon lab found that flies are partially blind each time they make a rapid flight turn. This happens because every time a fly turns, the image of the world sweeps over the retina and the fly needs a mechanism to ignore this massive self-generated sensory stimulus. The lab has discovered that fly visual neurons receive a quantitatively tailored, internally generated silencing input during turns. When humans make rapid eye movements, our brains face the same problem: We need to ignore the self-generated visual input caused by these movements. The silencing mechanism discovered in flies may illuminate similar processes in our own visual system.
In another line of work, the Maimon lab has discovered how the fly brain constructs an internal sense of orientation. Humans too have a robust sense of orientation in space, and its importance is made clear when we become disoriented upon exiting a subway station, or in the early stages of Alzheimer’s disease, when declines in spatial memory can make patients become easily lost or confused.
The Maimon lab has characterized a neuronal circuit in the Drosophila central complex—a set of structures in the middle of the fly brain—that allows flies to build and update an internal compass-like signal. This circuit operates even in complete darkness, wherein flies must internally integrate how much their legs are turning to update their sense of angular heading. The central features of this biological circuit are analogous to computational models proposed for how rodents build an internal sense of orientation, and may thus inform how any neural system performs mathematical integration.
The lab continues to study how flies calculate quantitatively accurate, spatial and nonspatial variables, and use these to guide behavior. This research program provides a platform for discovering basic mechanisms of how brains integrate, think, and decide.