The English speaking scientific and philosophical communities have been dominated by Humean associationism: empirical observations are stuck together to compose explanations of observations at a higher order. In brain science this approach dates from Viennese neurology of the latter part of the nineteenth century: sensory inputs become associated in “association areas of the cortex.”
Neuroconstructivism presents a different panorama. They see constructivist development as a progressive increase in the complexity of representations that is realized in the brain by a progressive elaboration of cortical structures. Interestingly, leads to ‘cleverer’ and not simply more knowledgeable organisms.
The authors describe this process as encellment, embrainment, embodiment, and ensocioment and give good reasons why each of these processes is necessary to provide a reasonably good understanding of the whole constructivist endeavor.
Without detracting from the enterprise as a whole, I do have some queries:
1. The authors' approach deals with complexity; why do they not explicitly say more about complexity theory, non-linear dynamics as it applies to one or another scales of investigation? (The exception is Chapter 5 written about a model by another author). They come close: They compare our world of artifacts, texts, media and cultural practices to the activity created whorls that form the “umwelt” of the blue fin tuna. Whorls serve as attractors in nonlinear dynamics. In the language of complexity theory, cultural practices when embrained through embodiment, serve as attractors.
2. Why do the authors limit themselves to neurons and circuits in their chapter on embrainment and, despite the acknowledgement that populations of cells not single cells are involved in processing, ignore processes occurring in the fine fiber structures of dendrites, and axonal branching where the populations interact? Again they come close: in their chapter on principles, mechanisms and processes they note that the emergent functionality of the individual neuron depends largely on the chemical and cellular context of the neuron. In short, the fine fiber, ephaptic, and synaptic processes (and even glia) are more important for progressive development and cognitive processing than the brain's neuronal circuitry. Though the authors do not recognize this, connectionist models actually deal mathematically with neuro-nodes that represent connections among neurons, connections occurring in the fine fibers of the brain, not neurons per se. This is because most modelers erroneously describe the nodes as neurons.
A few specific embellishments: In discussing Piaget and his contributions, the authors point out that there is a failure in his contributions to deal with the dynamics that move the child from one cognitive level to the next. Both Piaget and I wrote for years about equilibration, a static reaching of equilibrium. But for both of us this view changed with the advent of Prigogine's “temporary stabilities far from equilibrium” (Prigogine 1980; Prigogine & Stengers Reference Prigogine and Stengers1984). Piaget, Inhelder, and I discussed this issue and agreed that stabilization in the sense of temporary stabilities was a required necessary improvement over our earlier views. Again, it is important to make complexity theory, stabilities as attractors, explicit in Neuroconstructivism.
In the treatment of vision some weaknesses become evident. The authors are struggling to release themselves from current interpretations of the results of experiments. The authors correctly criticize the way in which the so-called dorsal and ventral visual pathways have been exploited: that often the pathways are activated in reverse (as there are just as many connections in the reverse direction – as I have also emphasized (Pribram Reference Pribram, Schmitt, Worden, Schmitt and Worden1974). They do not go the distance, however, to suggest that object constancy can precede the divergence of the two as suggested by the results of (Zeki Reference Zeki1983; Ungerleider et al. Reference Ungerleider, Ganz and Pribram1977).
Furthermore, the elimination of cortico-cortical and subcortical thalamic connections that presumably underlie the ventral pathway does not disturb visual processing, while when the relevant subcortical to cortical pathways are disrupted, visual processing by the inferotemporal cortex ceases. All of this evidence provides additional support for the conclusions arrived at by the authors in Neuroconstructivism (Pribram Reference Pribram, Lapore, Ptito and Jasper1986).
A last point about vision: In the second volume Chapter 2 is based on an isomorphic model of processing images in the primary visual pathway while Chapter 3 deals with processing in the same pathway in the spectral domain. The two points of departure are a matter of scale (gross vs. micro) but, as the two ways of dealing with imaging are very different, the differences should not be glossed over but addressed somewhere in the volume.
A final comment: The neuroconstructivist view predicts that representations will become progressively more fragmentary because they emerge within (and build on) increasingly complex representational contexts. In short, the representations are content, not location addressable. But retrieval codes are location addressable, thus there is some gross “localization of function” in brain systems.
In conclusion: Neuroconstructivism is, to my mind, a landmark contribution. I liked especially the treatment of habituation – and would add the amygdala and other basal ganglia systems to the discussion (see Pribram Reference Pribram2006). Also, the treatment of phonological development is seminal –[and I want to emphasize that the “motor cortex” in general – not only in audition – deals, not with the programming of movements, but with processing “targets” or “images of achievement” (see Pribram Reference Pribram1991).
As the reader can see, I am enthusiastic about the presentation that carries forward a program consonant with one that I envisaged (Pribram Reference Pribram, Worden and Nagel1965) to which the authors have already added much. Just what the journal Behavioral and Brain Science is so good at stimulating.
