 The core claim of a functional role semantics is that a representation has its specific content in virtue of relations it bears to other representations. Its paradigm application is to concepts of truth-functional logic, like the conjunctive “and” or disjunctive “or”. A physical event instantiates the “and” function just in case it maps two true inputs onto a single true output. Thus it is the relations an expression bears to others that give it the semantic content of “and”. Proponents of functional role semantics propose similar analyses for the content of all representations (Block 1995). A physical event represents birds, for example, if it bears the right relations to events representing feathers and others representing beaks. By contrast, informational semantics ascribe content to a state depending upon the causal relations obtaining between the state and the object it represents. A physical state represents birds, for example, just in case an appropriate causal relation obtains between it and birds. At the heart of informational semantics is a causal account of information (Dretske 1981, 1988). Red spots on a face carry the information that one has measles because the red spots are caused by the measles virus. A common criticism of informational semantics holds that mere causal covariation is insufficient for representation, since information (in the causal sense) is by definition always veridical while representations can misrepresent. A popular solution to this challenge invokes a teleological analysis of “function”. A brain state represents X by virtue of having the function of carrying information about being caused by X (Dretske 1988). These two approaches do not exhaust the popular options for a psychosemantics, but are the ones to which neurophilosophers have most contributed.