Publications of Place that refer to Jordan (1986). Attractor dynamics and parallelism in a connectionist sequential machine.
Place, U. T. (1993i). Following 'the natural lines of fracture': Concept formation in neural networks [Conference presentation, presented at the Symposium on Associationism, Behaviour Analysis and Connectionism, held at the Annual Conference of the Experimental Analysis of Behaviour Group, University College, London 31st March 1993].
It is an implication of Darwin's theory of evolution by variation and natural selection that the survival and reproduction of complex free-moving living organisms, animals in other words, depends on their ability to change the spatial relations between themselves and other objects, including other organisms of the same and of different species, and so bring about the conditions necessary for that survival and reproduction. In order to do that the organism requires a system - its nervous system - whose function is to match the output to the current stimulus input on the one hand and the organism's current state of deprivation with respect to conditions required for its survival and successful reproduction on the other. Matching behaviour to the conditions required for survival and reproduction is the function of the motivational/emotional part of the system. Matching behaviour to current stimulus input is the function of the sensory/cognitive part of the system. The sensory/cognitive system cannot perform its function successfully without the ability to group inputs together in such a way that every actual and possible member of the class or category so formed is a reliable indicator of the presence of an environmental situation in which a particular behavioural strategy or set of such strategies is going to succeed. In other words the survival and reproduction of an organism of this kind depends crucially on its having a conceptual scheme, a conceptual scheme moreover, which reliably predicts the actual behaviour-consequence relations operating in the organism's environment. Although verbs such as ‘classifying’, ‘categorizing’ and ‘conceptualizing’ are not to be found in Skinner's writings, there is an important passage in The Behavior of Organisms (Skinner 1938) where he addresses the issue which others talk about when they use such terms. Thus in Chapter One, after outlining his "System of Behavior", he goes on to say
The preceding system is based upon the assumption that both behavior and environment may be broken into parts which retain their identity throughout an experiment and undergo orderly changes. If this assumption were not in some sense justified, a science of behavior would be impossible. But the analysis of behavior is not an act of arbitrary sub-dividing. We cannot define the concepts of stimulus and response quite as simply as ‘parts of behavior and environment’ without taking account of the natural lines of fracture along which behavior and environment actually break. (Skinner 1938 p.33).
What Skinner has primarily in mind in this passage is the way the scientist's concepts need to be shaped into conformity with what he calls "the natural lines of fracture." But on the Darwinian argument the same must be true of the stimulus classes within which any living organism's behaviour generalises and between which it discriminates. It is argued that studying the properties of artificially constructed neural networks helps us to understand how the brain develops patterns of generalisation and discrimination which do indeed "follow the natural lines of fracture along which behavior and environment actually break." Attention is drawn to the role of the ‘hidden layer’ in responding to resemblances of pattern, to the role of re-entrant/recurrent and reverberatory circuits in establishing expectations on the basis of consecutive stimulus patterns, and to the role of error-correction in bringing stimulus classes into line with the contingencies experienced during learning.
Download: 1993i Following 'The Natural Lines of Fracture' - Concept Formation in Neural Networks.pdf
Place, U. T. (1999d). Connectionism and the problem of consciousness. Acta Analytica, 14(22), 197-226.
This paper falls into three parts. In Part 1 I give my reasons for rejecting two aspects of Horgan and Tienson's position as laid out in their book, the language of thought and belief-desire explanations of behaviour, while endorsing the connection they see between linguistic syntax and the syntax of a motor skill. In Part 2 I outline the theory that the brain consists of two input-output transformation systems consciousness whose function is (a) to categorise problematic inputs, (b) to select a response appropriate to such inputs once they have been categorised and (c) to initiate and monitor the execution of such response once selected, and the "zombie-within" whose function is (a) to identify and alert consciousness to any inputs that are problematic either because they are unexpected or because they are significant relative to the agent's current or perennial motivational concerns. In Part 3 I consider how far the properties of the two systems outlined in Part 2 can be understood in terms of the known properties of connectionist networks.
Keywords: connectionism, consciousness, problematic input, zombie-within
The download file contains some text added by the author after publication. Footnote 2 is added.
[References]  [1 referring publications by Place]
Download: 1999d Connectionism and the Problem of Consciousness.pdf
Place, U. T. (2000a). Consciousness and the zombie-within: a functional analysis of the blindsight evidence. In Y. Rossetti, & A. Revonsuo (Eds.), Beyond dissociations: Interaction between dissociated implicit and explicit processing (pp. 295-329). John Benjamins. doi:10.1075/aicr.22.15pla
Cowey & Stoerig's (1995) demonstration that the phenomenon of blindsight applies to monkeys with striate cortical lesions in the same way as it does to humans with similar lesions makes it plausible to argue that the behaviour of mammals and probably that of other vertebrates is controlled by two distinct but closely interdependent and interacting systems in the brain which I shall refer to respectively as 'consciousness' and the 'sub-conscious automatic pilot or "zombie" within'. On this hypothesis, consciousness has three functions, (a) that of categorizing any input that is problematic in that it is either unexpected or significant relative to the individual's current or perennial motivational concerns, (b) that of selecting a response appropriate both to the presence of a thing of that kind and to the individual's motivational concerns with respect to it, and (c) that of monitoring the execution of that response. Conscious/phenomenal experience, on this view, is the first stage in the process whereby problematic inputs are processed by consciousness. Its function is to modify the figure-ground relations within the central representation of a problematic input until an adequate categorization is selected. The sub-conscious automatic pilot or “zombie-within” has two functions (a) that of continuously scanning the total current input and alerting consciousness to any input it identifies as problematic, (b) that of protecting consciousness from overload either by ignoring those non-problematic inputs which require no response or by responding appropriately but automatically to those for which there already exists a well practised skill or other “instinctive” response pattern.
[References]  [Is cited by]  [4 referring publications by Place]  [Reprinting collections]
Download: 2000a Consciousness and the Zombie-within a Functional Analysis of the Blindsight Evidence.pdf