BRIAN simulator

I will now give a brief overview of different spike-based theories. This is not meant to be an exhaustive review – although I would be very glad to have some feedback on what other theories would deserve to be mentioned. My aim is rather to highlight a common theme in these theories, which distinguishes them [...]

I am starting a new series of posts on this blog, called « Reader’s digest ». These are simply bibliographical notes on recent readings (of recent or old papers). While reading Abeles’s Scholarpedia entry on synfire chains, I learned that while Abeles introduced the terms “synfire chains”, the concept is in fact older. It seems that it [...]

I explained in previous posts that new theories should not be judged by their agreement with the current body of empirical data, because these data were produced by the old theory. In the new theory, they may be interpreted very differently or even considered irrelevant. A few philosophers have gone so far as to state [...]

At this point, it should be clear that there is not a single type of theoretical work. I believe most theoretical work can be categorized into three broad classes: deduction, induction, and counter-induction. Deduction is deriving theoretical ... [More] knowledge from previous theoretical knowledge, with no direct reference to empirical facts. Induction is the process of making [...] [Less]

Paul Feyerabend was a philosopher of science who defended an anarchist view of science (in his book “Against Method”). That is, he opposed the idea that there should be methodologies imposed in science, because he considered that these are the expression of conservatism. One may not agree with all his conclusions (some think of him [...]

Since there is such an obvious answer, you might anticipate that I am going to question it! More precisely, I am going to analyze the following statement: a good theory is one that explains the maximum amount of empirical data while being as simple as possible. I will argue that 1) this is not stupid [...]

Slime molds are fascinating: these are unicellular organisms that can display complex behaviors such as finding the shortest path in a maze and developing an efficient transportation network. Actually each of these two findings generated a ... [More] high-impact publication (Science and Nature) and an Ignobel prize. In the latter study, the authors grew a slime mold [...] [Less]

According to the rate-based hypothesis, 1) neural activity can be entirely described by the dynamics of underlying firing rates and 2) firing is independent between neurons, conditionally to these rates. This hypothesis can be investigated in models ... [More] of spiking neural networks by a self-consistency strategy. If all inputs to a neuron are independent Poisson processes, [...] [Less]

In the 1990s, there was a famous published exchange about the rate vs. timing debate, between Softky and Koch on one side, and Shadlen and Newsome on the other side. Softky and Koch argued that if spike trains were random, as they seemed to be in single unit recordings, and cortical neurons sum many inputs, [...]

I have identified the rate-based hypothesis as a methodological postulate, according to which neural activity can entirely be described by underlying rates, which are abstract variables. In general, individual spikes are then seen as instantiations ... [More] of a random point process with the given rates. It can also be seen as a hypothesis of independence between [...] [Less]