Mapping the architecture of reference in the brain
Peter Viertbauer (University of Innsbruck, Austria)
For most communications, language cannot encode all the intended meaning. Even taking into account suprasegmental features, it requires a shared frame of reference for its functioning. Communication would be restricted to what is already known by the listener, if this reference was to an objective world. Perceptive filters shape what can be thought and said. Studying the meaning of language therefore necessarily means studying the filters of our perception. Apart from sensory restrictions these filters are mainly realized in the structures of the brain.
But complex functions like speech do not easily map to the neural architecture (Deacon1997). Distributed patterns of activity make it hard to distinguish linguistically relevant data. Attributing functions to certain brain areas works best in clearly perceptual structures, like the ones found along the visual pathway. There, at least two ordering principles are found, geometrical homology of the projection and a functional hierarchy of perceptual complexity (Hubel1987). The functional hierarchy itself tells a history of evolutionary adaptations. This history can be traced by comparing the architecture of brains in different species (Striedter2005).
The presented theoretical position follows a neurophilosophical argument on the meaning of neuronal spikes, developed in the authors forthcoming PhD thesis for the purpose of understanding necessary stages in language evolution. It starts from the assumption that the innovations in the architecture of the brain represent ontological differentiations in perceptual filters. From species behavior – conjectured from overview literature on comparative cognition (for instance Shettleworth2010) – and their respective neural architecture it is possible to extrapolate the complexity of the neuronal world representations they are reacting to. Rather than a functional map of the brain, this results in a ‘strata model’ of perceptual meaning. Such a model displays and characterizes the filtering of meaning in various brain areas. It is of linguistic relevance as a background for discussions of meaning, particularly the conceptual cornerstones throughout the evolution of language.
The paper aims at demonstrating how such a model could be established. It introduces a first approximation for the relevant differentiations in the course of biological evolution from chordates to primates. On this premise it will discuss how the stratification of perceptual filters in the brain could have shaped the evolution of language and linguistic structures themselves.
Deacon, Terrence W. 1997. The symbolic species. The co-evolution of language and the brain.New York:Norton.
Hubel, David H. 1987. Eye, brain and Vision.New York: W.H.Freeman.
Striedter, Georg F. 2005. Principles of Brain Evolution.Sunderland: Sinauer Associates.
Shettleworth, Sara J. 2010. Cognition, Evolution, and Behavior.Oxford: Oxford University Press.