Head-direction system

…The head direction system of the fruit fly, however, seems to achieve these properties with a remarkably small network. These findings challenge our understanding of ring attr

The internal compass of the brain, also known as the head-direction (HD) system, forms a crucial component of the neural circuit necessary for effective spatial orientation, and includes regions such as the anterodorsal thalamic nucleus (ADN). It maintains a sense of orientation by integrating self-motion with local cues, which serve as anchors. A recent study in mice showed that network gain, a measure of population activity in the system, decreases during reorientations induced by changes in visual cues. The extent of this reduction in gain influences the dynamics of reorientation, with lowe

Animal brains and behaviours have evolved in the natural world – to allow different species to meet their daily life challenges. However, our understanding of how the brain deals with such diverse conditions stems from constrained laboratory experiments – where an animal exhibits one specific behaviour in one particular task. While this approach has revealed many instances of how the brain can encode isolated behaviours, it leaves the fundamental question unexplored: How does the brain actually represent the real world – in natural and multi-animal settings? To answer this, we caught wild Egyp

…to determine the function of a neural system remains challenging, given the physiological properties of individual neurons that remain unconstrained. To address this, we developed a theory that describes the space of solutions when inferring activit

In this webinar on spatial navigation circuits, three researchers—Ann Hermundstad, Ila Fiete, and Barbara Webb—discussed how diverse species solve navigation problems using specialized yet evolutionarily conserved brain structures. Hermundstad illustrated the fruit fly’s central complex, focusing on how hardwired circuit motifs (e.g., sinusoidal steering curves) enable rapid, flexible learning of goal-directed navigation. This framework combines internal heading representations with modifiable goal signals, leveraging activity-dependent plasticity to adapt to new environments. Fiete explored t

…networks in the head direction system (Knierim et al., 2012, Hulse et al., 2020). However, we do not understand how the sense of direction is used to guide action. Drosophila connectome analyses (Rayshubskiy et al., 2020, Hulse et al., 2021) recently revealed two cell types (PFL2 and PFL3) that connect the head direction system to the locomotor system. These populations also receive a