Abstract
D. Litt. et Phil.
As its basic point of departure this thesis has a "neuro-epistemological"
concern in that it aims to analyse the epistemological status of paradigms for
modelling the organisation of brain processes and function. By rooting itself in
a post-modernist frame of reference it aims to provide a contextually-driven meta-analysis
of theories of brain function. This includes an analysis of the assumptive
frameworks underlying both the current orthodoxy (the Computational Theory of
Mind) and its polar opposite in ontological terms (the Microgenetic Theory). The
latter theory is seen as being "subjugated" in the post-modernist sense via the
implicit power relations held and practised through the hegemonic entrenchment
of the former dominant discourse.
An overview of the work of Maturana and Varela is then presented as a
theory that has positioned itself as a Via Media between the two radically
opposed ontologies. This Via Media is then critiqued from several angles in a
way that lays the groundwork for a model of neural organization and function that
is consistent with recent trends in the neurosciences as well as in cybernetics
and that is offered as a candidate for a more useful Via Media.
The general format of this new "Deconstructive Carving Model", which is
applied at the levels of neurodevelopmental process, visual perception and
consciousness is as follows: In the domain of explanation there is construed to occur a carving out of
a form from a pre-given, featureless medium in a general direction from diffuse
and amorphous to specific. This process, involving various active mechanisms,
is constrained, guided or restrained (rather than informed) by local and global,
internal and external contextual modulatory (rather than instructive) influences.
It occurs in an iterative, dynamic manner that is systematic (rather than arbitrary)
and is activity-dependent (rather than passive), utilizing both spatial and temporal
mechanisms. Given the proposed nature of the nervous system as partially
closed, the outcome of this interaction is seen as being state-dependent in that
the very structure of the system (as partially open to environmental specification)
will select what in the medium will serve as a perturbation and what it will allow
as a con straining influence. Finally, a stable anchor for these multi-level
processes is postulated in the form of relatively invariant peripheral body and
body-image representational constraints.