Voltage-gated Na(+) channel (VGSC) β1 subunits, encoded by SCN1B, are multifunctional channel modulators and cell adhesion molecules (CAMs). Mutations in SCN1B are associated with the genetic epilepsy with febrile seizures plus (GEFS+) spectrum disorders in humans, and Scn1b-null mice display severe spontaneous seizures and ataxia from postnatal day (P)10. The goal of this study was to determin...

Game pathfinding is a challenging problem due to a limited amount of per-frame CPU time commonly shared among many simultaneously pathfinding agents. The challenge is rising with each new generation of games due to progressively larger and more complex environments and larger numbers of agents pathfinding in them. Algorithms based on A* tend to scale poorly as they must compute a complete, poss...

Cumulative evidence suggests that neural network formation requires an ingenious regulation of the attractive and repulsive responses of growing axons to guidance cues. We examined the role of intracellular protein kinase A (PKA) signaling in the axonal pathfinding of olfactory sensory neurons in transparent zebrafish embryos. Microinjection of an olfactory marker protein gene promoter-driven d...

Any-angle pathfinding is a common problem from robotics and computer games: it requires finding a Euclidean shortest path between a pair of points in a grid map. Prior research has focused on approximate online solutions. A number of exact methods exist but they all require supra-linear space and preprocessing time. In this paper we describe Anya: a new optimal any-angle pathfinding algorithm w...

The intricate connections of the nervous system are established, in part, by elongating axonal fibers that are directed by complex guidance systems to home in on their specific targets. The growth cone, the major motile apparatus at the tip of axons, explores its surroundings and steers the axon along a defined path to its appropriate target. Significant progress has been made in identifying th...

Cooperative pathfinding is a problem of finding a set of non-conflicting trajectories for a number of mobile agents. Its applications include planning for teams of mobile robots, such as autonomous aircrafts, cars, or underwater vehicles. The state-of-the-art algorithms for cooperative pathfinding typically rely on some heuristic forward-search pathfinding technique, where A* is often the algor...

We give online and offline optimisation techniques to improve the performance of Jump Point Search (JPS): a recent and very effective symmetry-breaking algorithm that speeds up pathfinding in computer games. First, we give a new and more efficient procedure for online symmetry breaking by manipulating “blocks” of nodes at a single time rather than individual nodes. Second, we give a new offline...

In many computer interfaces the underlying structures and contingencies are often hidden from the user's view. Users high in Spatial Visualization Ability (SVA) are able to quickly determine and manage the contingencies of these relationships and are not severely affected by this problem. Low SVA users, however, have difficulty visualizing these contingencies and often get lost. We examined the...

Spontaneous, highly rhythmic episodes of propagating bursting activity are present early during the development of chick and mouse spinal cords. Acetylcholine, and GABA and glycine, which are both excitatory at this stage, provide the excitatory drive. It was previously shown that a moderate decrease in the frequency of bursting activity, caused by in ovo application of the GABA(A) receptor blo...

Hippocampal mossy fibers (MFs), axons of dentate granule cells, run through a narrow strip, called the stratum lucidum, and make synaptic contacts with CA3 pyramidal cells. This stereotyped pathfinding is assumed to require a tightly controlled guidance system, but the responsible mechanisms have not been proven directly. To clarify the cellular basis for the MF pathfinding, microslices of the ...