University at Buffalo (UB)
Wednesday, January 23, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
David Pierce, Ph.D.
Department of Computer Science and Engineering
University at Buffalo
Machine Learning Strategies for Corpus-Based
Natural Language Processing
Corpus-based natural language processing refers to the use of techniques from machine learning for training systems to understand natural language. These techniques generally require annotated training data as input. For example, building a parser requires pre-parsed sentences as input. This talk will consider strategies at a "meta-learning" level for using training data more efficiently and effectively. One such strategy, called active learning, tries to select training instances based on their predicted utility. Additionally, I will describe experiments demonstrating the effectiveness of strategies such as active learning for a simple natural language learning task, namely base noun phrase identification.
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Wednesday, January 30, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
David Fertig, Ph.D.
Department of Linguistics
University at Buffalo
"If no mere mortal has ever flown out to center field,
then what about Swiss pigs and tennis rackets?"
This talk will focus on one aspect of my work on the elationship between morphological processing and language change. Theories of how morphology is processed in the brain have diachronic implications, and conversely historical changes can be an important source of evidence for testing hypotheses about processing. My recent work has been concerned in particular with the dual-mechanism debate. Advocates of dual-mechanism models of morphological processing, such as Steven Pinker and Harald Clahsen, argue that there is a fundamental distinction between regular inflection, which they see as involving the operation of concatenative, symbol-manipulating rules, and irregular inflection, involving inflected forms stored in associative memory. Opponents of dual-mechanism models, such as David Rumelhart, James McClelland, and Joan Bybee, see associative memory at work in both regular and irregular inflection and deny the need for explicit rules and morphological structure.
One of the main pieces of evidence offered in support of the dual-mechanism hypothesis involves what I will call the "regularization-through-derivation effect" (RTDE). The basic observation is that words formed by conversion (category-changing zero derivation), e.g. denominal verbs like _to telephone_, are inflectionally regular. Dual-mechanism proponents claim that this is because irregular inflection is a property of individual morphemes in the mental lexicon, and words formed by conversion contain no morpheme of the appropriate lexical category (Noun, Verb, Adjective) with which irregularity could be associated. This supposedly accounts for "why no mere mortal has ever flown out to center field" (the title of a 1991 _Cognitive Science_ article by John Kim, Steven Pinker, Alan Prince, and Sandeep Prasada). The baseball verb _to fly (out)_ cannot be irregular because it is derived from the noun _fly (ball)_, so we say, _the batter flied out_, in spite of the homophonous underived irregular verb _fly-flew-flown_.
I will first argue, on theoretical grounds, that even if the RTDE held true without exception, as Pinker and others claim, it would actually have no direct relevance to the dual-mechanism debate, although it would still be of significant interest as evidence for the reality of formal derivational word structure. I will then turn to diachronic predictions that follow from the RTDE and show, based on findings from German and English verbal inflection, that the RTDE can lead us to valuable new insights into the motivations for many regularizations and irregularizations. These same findings reveal clearly, however, that the RTDE is merely a tendency, with numerous exceptions involving, among other things, Swiss pigs and tennis rackets. The status of the RTDE as a tendency rather than an absolute rule calls into question the claim that the effect constitutes strong evidence for the psychological reality of explicit morphological structure. I will discuss two alternative accounts of the RTDE, one which makes use of the interaction of ranked constraints on inflectional-class assignment and another based on a purely analogical model of morphological processing.
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Wednesday, February 6, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
"Receptors, Synapses, and
Information in the Retina"
Malcolm Slaughter, Ph.D.
Department of Physiology and Biophysics
University at Buffalo
The retina relies on only a few neurotransmitters, glutamate and GABA, to relay a diversity of information. Receptor subtypes take up the slack. Glutamate receptor subtypes are specialized for encoding information about the onset and offset of light. Glutamte receptors also encode temporal properties of light signals. GABA receptors form intensity discriminators. Overall, there is a linkage between receptor subtypes and the decomposition of visual information.
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Wednesday, February 20, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Suzanne Stevenson, Ph.D.
Department of Computer Science
University of Toronto, Toronto, Canada
"Learning Semantic Classes of Verbs
from Syntactic Frequencies"
Many current models of human sentence understanding postulate on-line use of very rich and articulated lexical entries for verbs. Especially important is the role of argument structure -- the participant roles assigned by a verb, and their mapping to syntactic position. In this work, we investigate factors that may contribute to the acquisition of verb argument structure. Specifically, we use computational experiments to explore the extent to which syntactic frequencies alone can discriminate verbs that differ in argument structure. Following Pinker and Levin, we assume that there is a regular correspondence between semantic verb classes and their syntactic behavior. We analyze the differing argument structures of some example verb classes, and devise simple syntactic features whose statistical patterns are predicted to reflect those differences in argument structure. We extract these statistical syntactic features from a corpus, and use them to train a machine learning algorithm to discriminate the verb classes. We demonstrate that a few simple statistical features are sufficient to achieve classification accuracy of around 70% -- on a task whose baseline is 33%. We conclude that simple syntactic frequencies can contribute to the acquisition of semantic verb classes, through their connection to argument structure properties. This is work in collaboration with Paola Merlo, Department of Linguistics, University of Geneva.
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Wednesday, February 27, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Helen Mayberg, M.D.
Rotman Research Institute
University of Toronto
"In Search of Depression Circuits:
The Functional Neuroimaging Evidence"
Resting-state abnormalities in regional glucose metabolism and blood flow using PET have been identified in patients with depression, including changes associated with treatment and clinical recovery. Although the relative contribution of individual regions varies as a function of clinical state, involvement of cortical, paralimbic and subcortical regions is seen across studies. Cortical deficits normalize with treatment (state effects); paralimbic and subcortical regions show a more complex state-trait pattern. Changes in these same regions are also seen with transient provoked sadness, with differences discriminating controls from depressed patients. Common patterns seen in both unipolar and bipolar patients suggest convergent pathways mediating disturbances in mood across diagnoses including a more generalized vulnerability to emotional stressors across patient groups. Formal testing of disease-specific and state-specific functional interactions among regions in this depression "network" provides a complementary perspective for future studies examining mechanisms underlying treatment response, relapse and disease vulnerability.
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Wednesday, March 6, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Ernest Lepore, Ph.D.
Center for Cognitive Science
Rutgers University
"An Abuse of Context in Semantics"
What is the role of context in semantics and pragmatics, what is context sensitivity, what counts as evidence for semantic context sensitivity, and how are we to distinguish it from pragmatic context sensitivity? Clear cases abound of both sorts of sensitivity. This paper will discuss and take a stand on the controversies surrounding the unclear cases.
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Wednesday, March 13, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Ray Jackendoff, Ph.D.
Program in Linguistics and Cognitive Sciences
Brandeis University, Waltham, MA
"Reintegrating Generative Grammar"
In the 1960s, generative grammar was widely acclaimed as offering a key to understanding the mind and human nature. Given the currently lowly status of linguistics in the cognitive neurosciences, the case can be made that this promise has not been fulfilled. Beside various sociological reasons for this failure, there were some good scientific reasons as well.
What was right about generative grammar was its focus on the individual's ability to produce and understand utterances, and in particular on the child's acquisition of this ability. This leads to the hypothesis of Universal Grammar, a human cognitive specialization for learning language - a hypothesis still subject to bitter dispute.
However, there was an important mistake at the heart of the technology of generative grammar: the assumption that the syntactic component is the sole course of combinatoriality, and that everything else is "interpretive." This assumption of "syntactocentrism" has been transmitted from Aspects model through Government-Binding Theory into the contemporary Minimalist Program.
The proper approach started to develop in phonology in the mid-1970s: the idea that phonological structure is the consequence of several independent generative systems connected by interface principles. This independence clearly extends to the relation between syntax and phonology (but syntacticians never caught on). Similarly, all substantive approaches to semantics since the 1970s have assumed an autonomous generative system; this is necessarily linked to syntax by interface constraints. The outcome is an architecture of multiple parallel generative components linked by interface components. All components can be interpreted as constraint systems, integrated by unification.
The parallel architecture leads to an integration within linguistics, in that it makes clear the interconnections among phonology, syntax, and semantics, as well as the
connection between phrasal combinatoriality and lexical combinatoriality (i.e. morphology). In addition, it leads to a far better integration with the rest of cognitive neuroscience in three respects. First, this architecture fits naturally into the larger architecture of the mind/brain. Second, it leads to a natural and flexible interpretation of the competence-performance distinction, in that the rules of grammar are directly involved in processing. Third, it leads to a natural story for the incremental evolution of the language capacity.
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2002 Distinguished Speaker Series
Wednesday, March 14, 2002
3:00 pm - 5:00 pm
280 Park Hall
North Campus
Ray Jackendoff, Ph.D.
Program in Linguistics and Cognitive Sciences
Brandeis University, Waltham, MA
"Possible Stages in the Evolution
of the Language Faculty"
The human ability to learn language is a human cognitive specialization, encoded (in some unknown way) in our genes. The evident adaptivity of linguistic communication suggests that this capacity arose through natural selection. It is therefore a challenge for linguistics to find a plausible route by which the features of language could have evolved step by step. I will propose such a route, using evidence from child and adult language acquisition, from aphasia, from pidgin and creole languages, from "language"-trained apes, and from "fossils" of earlier forms of the language capacity still found in modern-day languages.
Ray Jackendoff is Professor of Linguistics at Brandeis University, where he has taught since 1971. He is a Fellow of the American Academy of Arts and Sciences, President-Elect of the Linguistic Society of America, and past President of the Society for Philosophy and Psychology. He is author of "Semantics and Cognition", Languages of the Mind", Consciousness and the Computational Mind", and (with Fred Lerdahl) "A Generative Theory of Tonal Music". His most recent book, "Foundations of Language", is being published by Oxford University Press this winter 2001/2002..
Book signing sessions ("Foundations of Language") from 3:00pm - 3:30pm and from 5:00pm -5:30pm at Slee Concert Hall.
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Wednesday, March 20, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Center for Cognitive Science at UB
"Poster Session"
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Wednesday, April 3, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Judith Shedden, Ph.D.
Department of Psychology
McMaster University, Canada
"Visual selective attention to objects and their parts"
Our visual world is hierarchical in nature in the sense that almost any global object or scene can also be analyzed in terms of its local parts. The brain appears to process local and global information differently, revealed by well-studied phenomena such as global precedence (faster responses to global vs. local information), asymmetric interference patterns (global information interferes with local processing more than local interferes with global), lateralized neural responses (right hemisphere bias for global and left hemisphere bias for local processing), and the symmetry and automaticity of the level-repetition effect (priming of level-specific processing affects global and local elements equally even when global processing is dominant). A critical manipulation that affects many aspects of global vs. local selective processing is the variability of the information at the irrelevant level. When perceptual input at global and local levels is variable (changes from trial to trial), level-specific neural mechanisms are engaged in the left and right hemispheres producing robust competitive effects. These effects are reduced or eliminated when irrelevant perceptual input is invariable from trial to trial. I will present behavioural and event-related potential (ERP) data collected from normal subjects and from patients with unipolar depression or bipolar disorder while they direct attention to global vs. local elements. Aspects selective attention and control will be discussed in terms of competition from the irrelevant hierarchical level and in terms of perceptual and attentional dysfunction in mood disorders.
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Wednesday, April 10, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Mitsuaki Shimojo, Ph.D.
Department of Linguistics
University at Buffalo
"A mismatch between acceptability
judgment and discourse frequency -
the sentence processing view of
internally headed relative clause and
quantifier float in Japanese"
The past syntactic studies have mostly been concerned with grammaticality or acceptability of a given sentence, and this tradition may be seen as reflection of a theoretical focus on "competence", rather than "performance". However, such a scope of study would make us unable to see a mismatch between speaker's acceptability judgment and discourse tokens, and consequently the theoretical significance of such observation. In this study, I will discuss two syntactic phenomena regularly studied in Japanese syntax - internally headed relative clause and quantifier float construction, and point out a serious discrepancy between speaker's acceptability judgment for the constructions and the observed range of discourse distribution, which have been either unnoticed or disregarded as mere performance issue. While the discourse tokens are expected to reflect the discourse function of a given construction, I suggest that the observed mismatch also reflects a processing ground, where cognitive focus of attention and availability of memory resources interplay to define processing complexity. Furthermore, the discourse and processing based study of the syntactic phenomena points to interplay of the intrinsic discourse function of a given construction and the processingly characterized sentence complexity, and thus predicts the different patterns of token distribution for the two types of construction.
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Wednesday, April 17, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Susan Lederman, Ph.D.
Department of Psychology
Department of Computing Science and Information
Queens University, Canada
"Designing Haptic and Multimodal Interfaces for Teleoperation and Virtual Environments Systems:
A Cognitive Scientist's Perspective"
I will approach the design of haptic (tactual) and multimodal interfaces for teleoperation and virtual environments from a cognitive scientist's point of view. The haptic system is a neural system that uses inputs to mechanoreceptors that are embedded in skin, muscles, tendons and joints. Many living organisms use haptics to learn about the concrete world and its properties by means of purposive manual exploration. In this talk, I will present selected results from my research program on human haptics. First, I will discuss a series of psychophysical studies concerning the nature and consequences of exploratory manual movements for human haptic perception under conditions of free exploration and brief, initial contact. Then, I will explore the contribution of spatially distributed fingertip forces to our human sensory and perceptual capacities. As the human operator is an integral component of haptic and multimodal interfaces for teleoperation and virtual-environment systems, it is critical that we match the design characteristics of the hardware and software systems to the capabilities and limitations of the human operator. For each of the research projects above, I will also propose a number of design principles based on the scientific outcomes.
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Wednesday, April 17, 2002
2:00 pm - 4:00 pm
280 Park Hall
North Campus
Jeffry Pelletier, Ph.D.
Depts. Philosophy, Computing Science
University of Alberta, Canada
A Philosophical Look at Compositionality
Although it sounds like the start of a bad joke, I think it is true to say that there are two types of people in the (academic) world: those who look to the 'parts' of objects/phenomena they wish to explain or understand, and those who look to the way an object/phenomenon 'fits in with' other aspects of the world. Let's call these two groups "atomists" and "contextualists". There are various subtypes within each of the groups, and I wish to pick out the 'compositionalists' from within the atomistic group for further discussion.
My interest is with their views on the explanation of "meaning" in the realm of theories of natural language understanding. As a first pass, their view is that "the meaning of a complex expression is a function of the meanings of the parts, plus the mode of combination of those parts". This formulation leaves a number of issues open, and gives rise to differing accounts of the issue of semantic compositionality.
Besides trying to get straight on just what semantic compositionality is, I intend to discuss certain linguistic phenomena that have been brought forward as examples that show it to be "empirically false". I will consider what compositionalists might say about such examples, and I will consider whether the strategies they might invoke amount to showing that there is _no_ empirical issue involved at all. In this realm, I will also look at certain formal accounts of semantics that purport to show that "any semantics can be converted to a compositional semantics"...and that therefore there is no empirical content to the compositional/non-compositional debate.
In the end I will advocate a certain attitude toward semantic phenomena: they are best explained by an atomistic, but non-compositional theory.
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Wednesday, April 24, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Sheila Blumstein, Ph.D.
Department of Cognitive and Linguistic Sciences
Brown University
"The Mapping of Sound Structure to
the Lexicon: Evidence from Normal
Subjects, Aphasic Patients, and Neuroimaging"
This research explores how listeners map the properties of sound on to the lexicon (the mental dictionary) and investigates the neural basis of such processing. A series of experiments with both normal subjects and aphasic patients are discussed exploring the effects of phonological and acoustic-phonetic structure on lexical processing. Specifically, we investigated the extent to which phonological and acoustic-phonetic modifications of an auditorily presented prime stimulus affect the magnitude of semantic priming to a real word target in a lexical decision task. Results from normal subjects suggest that:
Results from aphasic patients suggest that they have deficits in the dynamics of lexical activation. Broca's aphasics appear to have an overall reduction in lexical activation, whereas Wernicke's aphasics appear to have an increase in lexical activation or a failure to inhibit lexical candidates. The potential neural systems underlying lexical activation will be considered based on recent neuroimaging findings with normal subjects.
Wednesday, September 4, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Helen Mayberg, M.D.
Rotman Research Institute
University of Toronto
"In Search of Depression Circuits:
The Functional Neuroimaging Evidence"
Resting-state abnormalities in regional glucose metabolism and blood flow using PET have been identified in patients with depression, including changes associated with treatment and clinical recovery. Although the relative contribution of individual regions varies as a function of clinical state, involvement of cortical, paralimbic and subcortical regions is seen across studies. Cortical deficits normalize with treatment (state effects); paralimbic and subcortical regions show a more complex state-trait pattern. Changes in these same regions are also seen with transient provoked sadness, with differences discriminating controls from depressed patients. Common patterns seen in both unipolar and bipolar patients suggest convergent pathways mediating disturbances in mood across diagnoses including a more generalized vulnerability to emotional stressors across patient groups. Formal testing of disease-specific and state-specific functional interactions among regions in this depression "network" provides a complementary perspective for future studies examining mechanisms underlying treatment response, relapse and disease vulnerability.
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Wednesday, September 11, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Gerald Penn, Ph.D.
Department of Computer Science
University of Toronto
"Topological Parsing"
Why is parsing so difficult in freer word-order (FWO) languages? The standard answer goes something like this: if the order among a phrase structure rule's daughter categories is not specified, then there will be exponentially many orderings to consider.
A great many more presuppositions carried by phrase structure are mistaken than just linear order, however - some of them quite fundamental, such as what a category represents. This talk summarises our progress on using insights from descriptive and generative linguistics to formalise new parsing models for FWO languages. Of particular benefit has been the recent re-examination of Slavic and Germanic syntax within HPSG and dependency grammar, which distinguishes at least two different varieties of constituency.
This distinction can be used during parsing, both for efficiency and for accommodating prosodic and discourse-level constraints into a syntactic model.
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Wednesday, September 25, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Ann Clock Eddins, Ph.D.
Department of Communicative Disorders and Sciences, UB
"Cortical Dynamics Associated with the
Perception of Complex Auditory Signals"
In recent years, there has been an increasing use of functional neuroimaging techniques to help improve our understanding of the brain regions involved in a variety of cognitive, sensory, and motor tasks. Specifically, we have been using positron emission tomography (PET) to study the relationship between auditory perception and cortical activation during discrimination tasks involving complex auditory stimuli. In this presentation, we will review results from two projects that have demonstrated dynamic cortical activation patterns that are dependent on both the detailed features of the sensory input as well as the cognitive demands of the discrimination task.
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Wednesday, October 2, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Marie-Ann Lescourret, Ph.D.
Institute for the History of Art
University of Strassbourg, France
"The Prehistory of Symbolic Forms"
How can we understand a work of art?
How is it that a work of art can be meaningful to us? My puzzlement arises from the fact that so many people can be touched by artistic productions elaborated in unknown languages, from unknown countries, from unknown cultures, and belonging to other times. How is it that we can be kept amazed, silent, gazing, in front of a painting by Raphael, or a symphony by Mozart, or an Amerindian statue?
We can find descriptions of such processes of understanding in history and in anthropology, but also in what Wittgenstein defines as the psychology of philosophy. I will show that the art historian Aby Warburg can throw light on the question of what happens in the process of understanding in the human brain. Warburg, also a philosopher and a psychologist, wondered why the same patterns always reappeared in different works of art, be it those of the American Indians, or those of the Italian Renaissance. The answer he gives to this question postulates the existence of a common human mental structure at work in the making and the understanding of a work of art.
Marie-Anne Lescourret is associate professor of aesthetics in the University of Strasbourg, France. She is the author of books on Rubens, Goethe, Levinas and Paul Claudel, and the translator of works by Newton and Wittgenstein.
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Wednesday, October 9, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Stuart Shanker, Ph.D.
Department of Psychology
Atkinson College, Canada
"Ape Language in a New Light"
In recent years we have seen a dramatic shift, in several different areas of communication studies, from an information-theoretic to a dynamic systems paradigm. In an information-processing system, communication, whether between cells, mammals, apes, or humans, is said to occur when one organism encodes information into a signal that is transmitted to another organism that decodes the signal. In a dynamic system, all of the elements are continuously interacting with and changing in respect to one another, and an aggregate pattern emerges from this mutual co-action. Whereas the information-processing paradigm looks at communication as a linear, binary sequence of events, the dynamic systems paradigm looks at the relation between behaviors and how the whole configuration changes over time. One of the most dramatic examples of the significance of shifting from an information-processing to a dynamic systems paradigm can be found in the debate over the interpretation of recent advances in ape language research (ALR). To some extent, many of the early ALR studies reinforced the stereotype that animal communication is functional and stimulus-bound, precisely because they were based on an information-processing paradigm that promoted a static model of communicative development. But Savage-Rumbaughs recent results with bonobos has introduced an entirely new dimension into this debate. Shifting the terms of the discussion from an information-processing to a dynamic systems paradigm not only highlights the striking differences between Savage-Rumbaughs research and earlier ALR studies, but further, it sheds illuminating light on the factors that underpin the development of communication skills in great apes and humans, and the relationship between communicative development and the development of language.
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Wednesday, October 16, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Stephen Grossberg, Ph.D.
Department of Cognitive and Neural Systems
Boston University
"Cortical Dynamics of Learning, Speech Perception,
and Word Recognition"
What is the neural representation of a speech code as it evolves in time? How do listeners integrate temporally distributed phonemic information into coherent representations of syllables and words? How does the brain extract invariant properties of variable-rate speech? More generally, what sorts of mechanisms encode temporal order during a complicated task like speech perception? This talk will describe an emerging neural model, variously called the PHONET, ARTPHONE, and ARTWORD model, that suggests answers to these questions, while quantitatively simulating challenging data about speech and word recognition. In this model, rate-dependent category boundaries emerge from feedback interactions between a working memory for short-term storage of phonetic items and a list categorization network for grouping sequences of items. The conscious speech and word recognition code is suggested to be a resonant wave, and a percept of silence is proposed to be a temporal discontinuity in the rate with which such a resonant wave evolves. Such a wave emerges when sequential activation and storage of phonemic items in working memory provides bottom-up input to unitized representations, or list chunks, that group together sequences of items of variable length. The list chunks compete with each other as they dynamically integrate this bottom-up information. The winning groupings feed back to provide top-down support to their phonemic items. These top-down expectations amplify and focus attention on consistent working memory items, while suppressing inconsistent working memory items. Feedback establishes a resonance which temporarily boosts the activation levels of selected items and chunks, thereby creating an emergent conscious percept. Because the resonance evolves more slowly than working memory activation, it can be influenced by information presented after relatively long intervening silence intervals. Variations in the durations of speech sounds and silent pauses can hereby produce different perceived groupings of words, and future sounds can influence how we hear past sounds. What functional reason explains why multiple levels of auditory processing may use resonant dynamics? A proposed answer is indicated by the fact that all the models have the acronym ART in their names. This is because they are special cases of Adaptive Resonance Theory. ART proposes how the processes whereby our brains continue to learn about a changing world in a stable fashion throughout life lead to conscious experiences. These processes include the learning of top-down expectations, the matching of these expectations against bottom-up data, the focusing of attention upon the expected clusters of information, and the development of resonant states between bottom-up and top-down processes as they reach an attentive consensus between what is expected and what is there in the outside world. It is suggested that all conscious states in the brain are resonant states, and that these resonant states trigger learning of sensory and cognitive representations. Thus, the speech models outlined above are proposed to be specialized versions of ART mechanisms for stably learning about temporally evolving information about the world.
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Wednesday, October 23, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Ann Bisantz, Ph.D.
Department of Industrial Engineering, UB
"Taking a Brunswikian approach to modeling
judgment in complex systems:
Implications for training support and design"
Brunswik's theories of human judgment, and their later mathematical formulations, have been widely applied in areas such as social judgment theory and medical diagnosis. More recently, researchers have begun applying this descriptive model of decision-making to human and automated judgment agents in complex, dynamic systems. This talk will discuss the modeling approach, and provide example applications and modeling extensions, as well as some resultant design implications, in command and control, process control, and aviation environments.
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Wednesday, October 30, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
David Shore, Ph.D.
Department of Psychology
McMaster University, Canada
"Confusing the Mind by Crossing the Hands: The Psychophysics, Neuropsychology and Neuroimaging of Tactile Remapping"
Interaction with our environment relies heavily on the use of our hands, which serve both as tools for manipulating objects and as receptor surfaces for perceiving those objects. This dual role means that the hands move constantly within peripersonal space as different postures are adopted. Tactile stimuli presented to the hands can be coded either in terms of their relative position on the body surface (a somatotopic frame of reference), or relative to some environmental (e.g., allocentric) or body-centered frame of reference. The present talk explores the abilities and limitations of the brain to accommodate various postures-linking visual with tactile information. Visuotactile illusions, tactile temporal order judgments, cross-modal congruency tasks (with normals and split-brain patients), and functional Magnetic Resonance Imaging are all used to demonstrate these factors in tactile remapping.
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Wednesday, November 6, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Barry Smith, Ph.D.
Department of Philosophy, UB
"SNAP and SPAN"
Many philosophers believe that truth is to be understood in terms of a relation between true sentences, on the one hand, and facts or states of affairs in the world, on the other. The latter are the truthmakers for the former. But consider the sentence: "John has been located in Atlanta for 35 years." What is it, in the world, which makes this sentence true? Well, perhaps some complex whole involving John, Atlanta, and a location relation stretching across 35 years. But John has exchanged all the molecules in his body many times in this 35 year period, and Atlanta may well have exchanged all its buildings. What, then, are the bearers of the location relation in the given case? I will argue that the impossibility of providing an answer to this question demands an overhaul of our common conceptions of language and ontology. Briefly: that nouns and verbs are in order as they stand (as, in the medical domain, anatomy and physiology are in order as they stand), but that the sentence is marked by the ontological equivalent of original sin.
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Wednesday, November 13, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Eduardo Mercado III, Ph.D.
Department of Psycology, UB
"Mammalian Memories of
Deeds Last Done"
Memory for personal experiences (episodic memory) is thought to rely on the ability to mentally travel back in time to consciously re-experience past events. Based on a lack of evidence of mental time traveling in non-humans, it has been proposed that this ability is unique to humans. This talk will present an alternative viewpoint. We propose that many mammals store and recall memories of personal experiences, and that cortical networks mediate this ability. Experimental data from dolphins, rats, and a chimpanzee demonstrate that non-humans can report on actions they have recently performed. Dolphins, in particular, can be trained to repeat prior actions on command, including self-selected actions and actions performed with particular objects. The recent discovery of "mirror neurons" in primate cortex, which fire both when a monkey performs an action, and when the monkey observes an action, provides important clues about how past actions are represented in memory.
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Wednesday, November 20, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
Michael Noonan, PhD.
Departments of Psychology and Biology
Canisius College, Buffalo, NY
"Evidence of cognitive processes in killer whales: A program of research underway at Marineland of Canada"
Killer Whales are characterized by long lives, complex social structures and one of the largest brains of any species on earth. This talk will present findings from a program of study on Killer Whales underway at Marineland of Canada that suggest a degree of convergence in the cognition of cetaceans with that of primates/humans.
The talk will concentrate on recently completed work that assessed the whales' ability to make "relative numerousness judgments" as an index of their ability to cope with quantity as a stimulus dimension. The findings show that these animals can indeed cope with quantitative discriminations in this way and in fact show their abilities in this regard to meet or exceed that shown by any other non-human species. Furthermore, analysis of their errors during task acquisition suggest a "Piagetian" pattern analogous to that shown by human children.
The talk will then include preliminary reports of work underway on mirror self recognition in killer whales, and on left-right asymmetry in response preference, both of which also imply convergence with primate/human cognition. The talk will end with new behavioral evidence suggestive of "intentionality" on the part of the whales and a discussion of how this additional, typically-human trait might be experimentally verified in Killer Whales.
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Wednesday, December 4, 2002
2:00 pm - 4:00 pm
280 Park Hall, North Campus
J. David Smith, PhD.
Department of Psychology, UB
"The Categorization Dilemma That Airport
Security Systems Face: And Why It Matters"
X-ray screeners at airport security checkpoints perform an important categorization task in which they detect targets amidst multiple, overlapping images. Their performance must be evaluated to gauge the security system's adequacy. A natural and feasible approach to evaluation is to build a library of target images and test screeners by sampling from these. We built the Screener categorization task to assess this library approach from the perspective of the categorization literature. In the Screener task, participants search for members of target categories in complex displays like those that luggage presents. We find that when targets are sampled from a library with repetition so that familiarity develops, participant screeners rely on recognizing familiar targets instead of applying category-general knowledge. These results ground experimentally similar observations that have been made within non-domestic aviation security (i.e., observations of familiarity effects in the detection of ecological threat images). These effects may illuminate the processes of categorization under conditions of visual complexity. They also suggest that the library approach to evaluation risks failures of security wherein unfamiliar targets go undetected. We consider an alternative approach.