Information flow

It has long been believed that the brain is highly modular both in terms of structure and function, although recent evidence has led some to question the extent of both types of modularity. We used artificial neural networks to test the hypothesis that structural modularity is sufficient to guarantee functional specialization, and find that in general, this doesn't necessarily hold. We then systematically tested which features of the environment and network do lead to the emergence of specialization. We used a simple toy environment, task and network, allowing us precise control, and show that

The last decade has brought us riches of connectomes from several species. Even though these detailed snapshots provide substantial insight into structure, composition and connectivity of neural networks, they fall short of explaining the dynamics they support. This stems from the difficulty to derive cellular model parameters, e.g., cell type and synaptic strengths, from fixed tissue. Additionally, neural systems are often governed by so-called ‘wireless’ connectivity, i.e., neuromodulation, controlling network state by way of volumetrically dispensed transmitters. What we can learn from a co

…However, whether information relevant to the behavior is actually transferred between areas is often untested. Here, we developed and used information theoretic tools to identify, in neural activity, encoding and transmission of information relevant to behavior. We then used these new methods to quantify how motor cortex and striatum encode and exchange behaviorally relevant information about specific reach-to-grasp movement featur

…which schematizes how pathways of information flow impact learning dynamics within an architecture. Because of the gating, these networks can compute nonlinear functions of their input. We derive an exact reduction and, for certain cases, exact solutions to the dynamics of learning. The reduction takes the form of a neural race with an implicit bias towards shared representations, which then govern the model’s ability to syste

The rodent medial prefrontal cortex (mPFC) is considered central in executive functioning and decision making, and from an anatomical perspective there is consensus that the mPFC is not a single homogenous structure. However, the nature of mPFC is more contentious in the functional domain, with disagreement as to whether mPFC is homogenous, or instead composed of multiple distinct subregions with distinct roles. To answer this question it is necessary to monitor activity across a wide swath of mPFC as rats actively engage prefrontal processing, and critically, to precisely identify the anatomi

Regulation of information flow in the brain is critical for many forms of behavior. In the process of sensory based decision-making, decisions about future actions are held in memory until enacted, making them potentially vulnerable to distracting sensory input. Therefore, gating of information flow from sensory to motor areas could protect memory from interference during decision-making, but the underlying network mechanisms are not understood. I will present our recent experimental and modeling work describing how information flow from the sensory cortex can be gated by state-dependent front

In recent years it has become increasingly clear that (Shannon) information is a central resource for organisms, akin in importance to energy. Any decision that an organism or a subsystem of an organism takes involves the acquisition, selection, and processing of information and ultimately its concentration and enaction. It is the consequences of this balance that will occupy us in this talk. This perception-action loop picture of an agent's life cycle is well established and expounded especially in the context of Fuster's sensorimotor hierarchies. Nevertheless, the information-theoretic persp