Teleosemantics and Productivity

There has been much discussion of so-called teleosemantic approaches to the naturalisation of content. Such discussion, though, has been largely confined to simple, innate mental states with contents such as There is a fly here. Even assuming we can solve the issues that crop up at this stage, an account of the content of human mental states will not get too far without an account of productivity: the ability to entertain indefinitely many thoughts. \ud The best-known teleosemantic theory, Millikan’s biosemantics, offers an account of productivity in thought. This paper raises a basic worry about this account: that the use of mapping functions in the theory is unacceptable from a naturalistic point of view

Serotonin system implication in L-DOPA-induced dyskinesia: from animal models to clinical investigations

In the recent years, the serotonin system has emerged as a key player in the induction of l-DOPA-induced dyskinesia (LID) in animal models of Parkinson's disease. In fact, serotonin neurons possess the enzymatic machinery able to convert exogenous l-DOPA to dopamine (DA), and mediate its vesicular storage and release. However, serotonin neurons lack a feedback control mechanism able to regulate synaptic DA levels. While in a situation of partial DA depletion spared DA terminals can buffer DA released from serotonin neurons, the progression of DA neuron degeneration impairs this protective mechanism, causing swings in synaptic DA levels and pulsatile stimulation of post-synaptic DA receptors. In line with this view, removal of serotonin neurons by selective toxin, or pharmacological silencing of their activity, produced complete suppression of LID in animal models of Parkinson's disease. In this article, we will revise the experimental evidence pointing to the important role of serotonin neurons in dyskinesia, and we will discuss the clinical implications. © 2014 Carta and Tronci

Green's Functions for Translation Invariant Star Products

We calculate the Green functions for a scalar field theory with quartic interactions for which the fields are multiplied with a generic translation invariant star product. Our analysis involves both noncommutative products, for which there is the canonical commutation relation among coordinates, and nonlocal commutative products. We give explicit expressions for the one-loop corrections to the two and four point functions. We find that the phenomenon of ultraviolet/infrared mixing is always a consequence of the presence of noncommuting variables. The commutative part of the product does not have the mixing.Comment: 18 Page

Ricci solitons - The equation point of view

We discuss some classification results for Ricci solitons, that is, self similar solutions of the Ricci Flow. Some simple proofs of known results will be presented. In detail, we will take the equation point of view, trying to avoid the tools provided by considering the dynamic properties of the Ricci flow.Comment: Revised Version - Corrected some mistakes and inaccuracie

Treating Coordination with Datalog Grammars

In previous work we studied a new type of DCGs, Datalog grammars, which are inspired on database theory. Their efficiency was shown to be better than that of their DCG counterparts under (terminating) OLDT-resolution. In this article we motivate a variant of Datalog grammars which allows us a meta-grammatical treatment of coordination. This treatment improves in some respects over previous work on coordination in logic grammars, although more research is needed for testing it in other respects

Representations are Rate-Distortion Sweet Spots

Information is widely perceived as essential to the study of communication and representation; still, theorists working on these topics often take themselves not to be centrally concerned with "Shannon information", as it is often put, but with some other, sometimes called "semantic" or "nonnatural",kind of information. This perception is wrong. Shannon's theory of information is the only one we need. I intend to make good on this last assertion by canvassing a fully (Shannon) informational answer to the metasemantic question of what makes something a representation, for a certain important family of cases. This answer and the accompanying theory, which represents a significant departure from the broadly Dretskean philosophical mainstream, will show how a number of threads in the literature on naturalistic metasemantics, aimed at describing the purportedly non-informational ingredients in representation, actually belong in the same coherent, purely information-theoretic picture

Representations are Rate-Distortion Sweet Spots

Information is widely perceived as essential to the study of communication and representation; still, theorists working on these topics often take themselves not to be centrally concerned with "Shannon information", as it is often put, but with some other, sometimes called "semantic" or "nonnatural",kind of information. This perception is wrong. Shannon's theory of information is the only one we need. I intend to make good on this last assertion by canvassing a fully (Shannon) informational answer to the metasemantic question of what makes something a representation, for a certain important family of cases. This answer and the accompanying theory, which represents a significant departure from the broadly Dretskean philosophical mainstream, will show how a number of threads in the literature on naturalistic metasemantics, aimed at describing the purportedly non-informational ingredients in representation, actually belong in the same coherent, purely information-theoretic picture

Deception as Cooperation

I develop a rate-distortion analysis of signaling games with imperfect common interest. Sender and receiver should be seen as jointly managing a communication channel with the objective of minimizing two independent distortion measures. I use this analysis to identify a problem with 'functional' theories of deception, and in particular Brian Skyrms's: there are perfectly cooperative, non-exploitative instances of channel management that come out as manipulative and deceptive according to those theories