Function, selection, and construction in the brain

Abstract

A common misunderstanding of the selected effects theory of function is that natural selection operating over an evolutionary time scale is the only function-bestowing process in the natural world. This construal of the selected effects theory conflicts with the existence and ubiquity of neurobiological functions that are evolutionary novel, such as structures underlying reading ability. This conflict has suggested to some that, while the selected effects theory may be relevant to some areas of evolutionary biology, its relevance to neuroscience is marginal. This line of reasoning, however, neglects the fact that synapses, entire neurons, and potentially groups of neurons can undergo a type of selection analogous to natural selection operating over an evolutionary time scale. In the following, I argue that neural selection should be construed, by the selected effect theorist, as a distinct type of function-bestowing process in addition to natural selection.After explicating a generalized selected effects theory of function and distinguishing it from similar attempts to extend the selected effects theory, I do four things. First, I show how it allows one to identify neural selection as a distinct function-bestowing process, in contrast to other forms of neural structure formation such as neural construction. Second, I defend the view from one major criticism, and in so doing I clarify the content of the view. Third, I examine drug addiction to show the potential relevance of neural selection to neuroscientific and psychological research. Finally, I endorse a modest pluralism of function concepts within biology.

The functions of imitative behaviour in humans

“…While natural selection is the most obvious mechanism that gives rise to S‐Functions, several theorists (e.g., Millikan, ; Papineau, ) have argued that any process in which a trait aids in the reproduction or replication of its bearer when compared with alternative traits, including cultural and linguistic evolution and “trial and error” learning, can generate S‐Functions. More recently, Garson (, ) has argued for a more liberal notion of selection in which the S‐Function of a trait can be defined by its contribution to the persistence rather than the replication of its bearer within a population. Garson's account, therefore, allows S‐Functions to be attributed to non‐replicating processes that, nonetheless, involves selection between different alternatives such as neural selection or, in the case of imitation, the selection of specific behaviours.…”

Social-Computation-Supporting Kinds

“…According to the work of Justin Garson, "in order to acquire a new function, a trait need not have contributed to its own reproduction (i.e., making copies of itself). It need only have done something that allowed it to persist better (longer, more effectively) than some alternative trait within a population" (2017, 524; see also Garson 2011Garson , 2012. Trait-differential persistence of instances is the source of their function.…”

Teleosemantics, selection and novel contents

“…There are actually different types of neural selection, depending on the neural structure that undergoes competitive interactions: synapse selection, whole neuron selection, and, possibly neural group selection (Garson 2012). Here we will focus on synapse selection, both because it is empirically well-documented and because it is most directly involved in creating new representations.…”

“…The relevant notion of selection can be broadened to include other processes as well. For example, Millikan (1984), Papineau (1984Papineau ( , 1987Papineau ( , 1993, and Garson (2012) have argued that the trial-anderror shaping of behaviours and underlying neural structures should count as a functionbestowing selection process, because of its resemblance to natural selection in the evolutionary sense. These kinds of ontogenetic selection processes suggest one way in which teleosemantics can solve the problem of novel contents.…”