Summary of PSYCOLOQUY topic Language Network

Topic:
Title & AuthorAbstract
5(46) SUBSYMBOLIC NATURAL LANGUAGE PROCESSING:
AN INTEGRATED MODEL OF SCRIPTS, LEXICON, AND MEMORY
[Cambridge, MA: MIT Press, 1993 15 chapters, 403 Pages]
Precis of Miikkulainen on Language-Network
Risto Miikkulainen
Department of Computer Sciences
The University of Texas at Austin
Austin, TX 78712

risto@cs.utexas.edu
Abstract: Distributed neural networks have been very successful in modeling isolated cognitive phenomena, but complex high-level behavior has been amenable only to symbolic artificial intelligence techniques. Aiming to bridge this gap, this book describes DISCERN, a complete natural language processing system implemented entirely at the subsymbolic level. In DISCERN, distributed neural network models of parsing, generating, reasoning, lexical processing and episodic memory are integrated into a single system that learns to read, paraphrase, and answer questions about stereotypical narratives. Using DISCERN as an example, a general approach to building high-level cognitive models from distributed neural networks is introduced, and the special properties of such networks are shown to provide insight into human performance. In this approach, connectionist networks are not only plausible models of isolated cognitive phenomena, but also sufficient constituents for generating complex, high-level behavior.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(56) HIERARCHICAL FEATURE MAPS AND BEYOND
Book review of Miikkulainen on Language-Network
Ben Goertzel
Computer Science Department
Waikato University
Hamilton, New Zealand

goertzel@waikato.ac.nz
Abstract: Hierarchical self-organizing feature maps, as implemented in the context of DISCERN, represent an important step toward a computational model of human memory. However, as Miikkulainen points out, these maps lack the ability to incorporate novel information on an ongoing basis (1993). It is suggested that in order to transcend this limitation the distinction between memory and processing will have to be eliminated in favor of a more system-theoretic point of view.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(57) BIOLOGICAL CONSTRAINTS AND THE REPRESENTATION OF
STRUCTURE IN VISION AND LANGUAGE
Book Review of Miikkulainen on Language-Network
Shimon Edelman
Dept. of Applied Mathematics & Computer Science
The Weizmann Institute of Science
Rehovot 76100, ISRAEL

edelman@wisdom.weizmann.ac.il
Abstract: The computational building blocks of biological information processing systems are highly interconnected networks of simple units with graded overlapping receptive fields, arranged in maps. In view of this basic constraint, it is proposed that the present stage in the study of cognition should concentrate on gaining understanding of the cognitive system at the level of the distributed computational mechanism. The model of script understanding introduced in the Miikkulainen's (1993) book appears promising, both because it treats seriously the question of the architecture of the language processor, and because its architectural features resemble those used in modeling other cognitive modalities such as vision.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(77) NARROWING THE GAP: MIIKKULAINEN AND THE
CONNECTIONIST MODELING OF LINGUISTIC COMPETENCE
Book Review of Miikkulainen on Language-Network
Paul Deane
Cognitive Modalities Project
Dataware Technologies
Ottawa, Canada

an995@freenet.carleton.ca
Abstract: Despite its early promise, connectionism has had a minimal impact upon linguistic theory -- largely because it has proved very difficult to scale neural network models up to the size necessary to handle realistic linguistic data. Miikkulainen's (1993) work on script comprehension demonstrates that such scaling-up is possible. Miikkulainen's technique -- the construction of a complex system incorporating multiple neural nets -- is biologically plausible and replicates important psycholinguistic findings about language processing. However, Miikkulainen's system lacks the properties which most linguists would consider diagnostic of human language. Its simple template-matching system lacks grammatical structure (morphology and syntax), and supports neither generativity of form nor compositionality of semantics. These difficulties can probably be overcome in future work, but will require connectionists to address the mathematical and theoretical issues inherent in multiple-network models of the sort Miikkulainen employs.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(78) DISCERN AS A COGNITIVE MODEL AND COGNITIVE
MODELLING FRAMEWORK
Book Review of Miikkulainen on Language-Network
Ronan Reilly
Dept. of Computer Science
University College Dublin

rreilly@nova.ucd.ie
Abstract: In this review, I evaluate the degree to which I feel Miikkulainen has achieved the goals he set himself in developing DISCERN. On the positive side, I argue that DISCERN is a significant achievement in that it demonstrates the feasibility of building large-scale connectionist systems that exploit the capabilities of distributed representations. The techniques embodied in the FGREP component are important and should prove useful in other applications. On the negative side, however, I consider that DISCERN represents a missed opportunity. I do not believe that scripts tell us much that is useful about real natural language processing, nor do I believe that a system designed to process scripts can be an informative basis for cognitive modelling.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(79) THE ROLE OF NEURAL NETWORKS IN COGNITIVE SCIENCE:
EVOLUTION OR REVOLUTION?
Book Review of Miikkulainen on Language-Network
Itiel E. Dror and Michael J. Young
Department of Psychology
Benton Hall
Miami University
Oxford, OH 45056, USA

idror@miavx1.acs.muohio.edu youngmj@miavx1.acs.muohio.edu
Abstract: Can the neural network approach to understanding cognition produce a revolution within cognitive science and re-shape our basic conceptualization of cognition and mind? Miikkulainen's (1993) efforts in developing a neural network system using results of symbolic research clearly demonstrate the extra explanatory power of the neural network approach. However, this line of neural network research limits their possible role in cognitive science.

Keywords: neural networks, philosophy of language, symbolic models of cognition

5(85) STORAGE AND REORGANIZATION IN EPISODIC MEMORY
Reply to Goertzel on Language-Network
Risto Miikkulainen
Department of Computer Sciences
The University of Texas at Austin
Austin, TX 78712

risto@cs.utexas.edu
Abstract: Goertzel's (1994b) review points out that the episodic memory model of DISCERN (Miikkulainen, 1993, 1994) lacks certain fundamental properties of human memory, such as a capability for reorganization, and suggests that the distinction between memory and processing must be eliminated. His points are well taken, but in light of the emerging understanding of the episodic memory system in the brain, I will argue that such a distinction is justified.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(86) REPRESENTATION OF STRUCTURE ON LINGUISTIC MAPS
Reply to Edelman on Language-Network
Risto Miikkulainen
Department of Computer Sciences
The University of Texas at Austin
Austin, TX 78712

risto@cs.utexas.edu
Abstract: In his review of Subsymbolic Natural Language Processing (Miikkulainen, 1993, 1994), Edelman (1994) makes several useful analogies between language processing and vision. His main argument is that approaches based on common information processing principles in the brain, such as maps and receptive fields, are more likely to lead to insights into human cognition. I very much agree with this idea, and discuss a few concrete ways in which language processing models can benefit from principles in use in current visual processing models.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(87) MODULARITY OF MIND, CEREBRAL LOCALISATION AND
CONNECTIONIST NEUROPSYCHOLOGY
Book Review of Miikkulainen on Language-Network
Robert William Kentridge
Psychology Department
Univerity of Durham
Durham DH1 3LE England

robert.kentridge@durham.ac.uk
Abstract: Although Miikkulainen's DISCERN (1993) is a model of cognition and not the brain, its completely connectionist construction and similarities between the effects of damage on its behaviour and the neuropsychology of dyslexia may tempt us to treat it as a brain model. In particular, we may draw parallels between the architecture of DISCERN and localisation of function in the cortex. I argue that "modularity" of the brain may be organised in terms of time-scales as well as space. Forms of "brain-damage" in connectionist neuropsychology may differ profoundly from those causing similar effects in people.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

5(88) REPRESENTATION IN MODULAR NETWORKS
Book review of Miikkulainen on Language-Network
Richard Cooper
Department of Psychology
University College London
London WC1E 6BT, United Kingdom

r.cooper@psychol.ucl.ac.uk
Abstract: The key feature in the success of DISCERN (1993) is not its connectionist underpinnings but the modularity inherent in its design. This modularity leads to the implementation of a version of Fodor's language of thought hypothesis. The question for connectionists, then, concerns whether such a language of thought is inevitable in modular connectionist systems.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

6(02) SUBSYMBOLIC PROCESSING OF EMBEDDED STRUCTURES
Reply to Deane on Language-Network
Risto Miikkulainen
Department of Computer Sciences
The University of Texas at Austin
Austin, TX 78712

risto@cs.utexas.edu
Abstract: Deane (1994) points out that the template-matching approach of DISCERN (Miikkulainen, 1993; 1994a) cannot scale up to realistic linguistic input without fundamental modifications such as a stack or a short-term memory. I agree with this observation and will briefly discuss a more sophisticated parsing model that employs some of the methods Deane suggests.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

6(03) COMPUTATIONAL CONSTRAINTS AND THE
ROLE OF SCRIPTS IN STORY UNDERSTANDING
Reply to Reilly on Language-Network
Risto Miikkulainen
Department of Computer Sciences
The University of Texas at Austin
Austin, TX 78712

risto@cs.utexas.edu
Abstract: The computational constraints obtained from symbolic models (as well as large, integrated connectionist models) can serve to guide research in subsymbolic cognitive science where neuroscience and psycholinguistics do not provide enough data. One such idea is scripts, which turns out to have a natural and powerful implementation in the subsymbolic framework as regularities in experience. Scripts serve an important role in story processing in that they allow us to leave out details and focus on the important events. Story processing beyond scripts, however, seems to involve mechanisms whose connectionist implementation would require a high-level monitor on top of the statistical components.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

6(04) SYMBOLIC AND SUBSYMBOLIC COGNITIVE SCIENCE
Reply to Dror & Young on Language-Network
Risto Miikkulainen
Department of Computer Sciences
The University of Texas at Austin
Austin, TX 78712

risto@cs.utexas.edu
Abstract: Symbolic and subsymbolic cognitive science can be seen as not competing but complementary approaches, serving different roles. Even though they are perhaps based on incompatible foundations, symbolic research can serve as a guideline for developing subsymbolic models, pointing out ways in which a large cognitive process could be broken apart and made tractable with current techniques.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.

7(34) WHERE DOES STORY GRAMMAR COME FROM?
Book Review of Miikkulainen on Language-Network
Csaba Pleh and Zsuzsa Kaldy
Department of General Psychology
Eoetvoes Lorand University
P.O. Box 4 H-1378
Budapest, Hungary

pleh@izabell.elte.hu Kaldy@izabell.elte.hu
Abstract: This commentary discusses some problems that we have encountered with Miikkulainen's language processing model, DISCERN, described in his book, Subsymbolic Natural Language Processing: An Integrated Model of Scripts, Lexicon, Memory (1993). First, DISCERN uses grammatical analysis in an unclarified manner. It assumes certain notions like Cases without giving them a connectionist account, and also presupposes a preliminary syntactic analysis. Neither the categories nor the temporal relations are connected to research on human parsing. Second, the relations between sentence parsing and story parsing are left unclear. Third, the story material used is extremely constrained. These constraints (one actor, one plot, etc.) are not trivial and seriously limit the scope of the model for human story processing.

Keywords: computational modeling, connectionism, distributed neural networks, episodic memory, lexicon, natural language processing, scripts.