Collaborating Authors

Biology: Scientists play MC Hammer to baby zebrafish to learn how they develop hearing underwater

Daily Mail - Science & tech

Scientists are playing MC Hammer to baby zebrafish in order to understand how they develop their hearing underwater. After developing a special speaker system to play music to the fish, Australian neuroscientists imaged the brains of the larval zebrafish to see which cells reacted. They found that young zebrafish have considerably better hearing than was thought -- with the capacity to react to both high and low frequency sounds. People do not often consider the hearing of fish underwater, the researchers said, but such is critical to find food, communicate with each other and escape predators. The study attracted the attention of MC Hammer himself, who tweeted a link to it.

Genes Can Affect How We Respond To Environmental Chemicals

Forbes - Tech

New research shows that a difference in genetics can influence how two individuals respond to the same environmental chemical. It's well known that humans and other animals can have highly variable responses to chemicals. Those chemicals might be medicines that either work quite well or not very well at all from person to person, or perhaps have side effects that are tolerable in one person, but potentially toxic in another. Individuals can also respond quite differently to a range of other chemicals in the environment, including industrial chemicals, metals, pesticides and other pollutants. However, not much is known about why such variation occurs from one person to another or from one population to another.

Want to be a winner? It really is mind over matter: Study discovers the brain circuits that decide whether fights are won or lost

Daily Mail - Science & tech

Sports stars such as Sir Steve Redgrave and Muhammad Ali claim a positive mental attitude is the most important part of preparing for a big race or bout in the ring. Now scientists have uncovered the uncovered the physical circuits in the brain that determine whether a fight will be won or lost. Deep within the brain, in a structure called the habenula, two neural circuits work in a complex interplay to influence the outcome of a battle. Scientists have uncovered the uncovered the physical circuits in the brain that determine whether a fight will be won or lost. This image shows changes in nerve excitation from the habenula region in a winner and loser zebrafish.

Integrative Biological Simulation, Neuropsychology, and AI Safety Artificial Intelligence

We propose a biologically-inspired research agenda with parallel tracks aimed at AI and AI safety. The bottom-up component consists of building a sequence of biophysically realistic simulations of simple organisms such as the nematode Caenorhabditis elegans, the fruit fly Drosophila melanogaster, and the zebrafish Danio rerio to serve as platforms for research into AI algorithms and system architectures. The top-down component consists of an approach to value alignment that grounds AI goal structures in neuropsychology. Our belief is that parallel pursuit of these tracks will inform the development of value-aligned AI systems that have been inspired by embodied organisms with sensorimotor integration. An important set of side benefits is that the research trajectories we describe here are grounded in long-standing intellectual traditions within existing research communities and funding structures. In addition, these research programs overlap with significant contemporary themes in the biological and psychological sciences such as data/model integration and reproducibility.

Point process latent variable models of larval zebrafish behavior

Neural Information Processing Systems

A fundamental goal of systems neuroscience is to understand how neural activity gives rise to natural behavior. In order to achieve this goal, we must first build comprehensive models that offer quantitative descriptions of behavior. We develop a new class of probabilistic models to tackle this challenge in the study of larval zebrafish, an important model organism for neuroscience. Larval zebrafish locomote via sequences of punctate swim bouts--brief flicks of the tail--which are naturally modeled as a marked point process. However, these sequences of swim bouts belie a set of discrete and continuous internal states, latent variables that are not captured by standard point process models. We incorporate these variables as latent marks of a point process and explore various models for their dynamics. To infer the latent variables and fit the parameters of this model, we develop an amortized variational inference algorithm that targets the collapsed posterior distribution, analytically marginalizing out the discrete latent variables. With a dataset of over 120,000 swim bouts, we show that our models reveal interpretable discrete classes of swim bouts and continuous internal states like hunger that modulate their dynamics. These models are a major step toward understanding the natural behavioral program of the larval zebrafish and, ultimately, its neural underpinnings.