Prototype effects in discourse and the synonymy issue: Two Lakota postpositions

Despite of being fully synonymous at the semantic level, the postpositions el "locative/directional" and ekta "locative/directional" in Lakota (Siouan, Central North America) display different semantic cores in discourse: the semantic prototype for el is the role of locative, while the semantic prototype for ekta is the role of directional. Both the functional synonymy between el and ekta and the observed prototype effects can be attributed to constellations created by grammaticalization processes: when an innovative grammatical element is developing-in this case, ekta-replacement of a functionally equivalent older element-in this case, el-is unlikely, to happen overnight, so that the innovative and the older element can be expected to coexist for a while, and to share functional domains

Prototype constructions in early language acquisition

In this paper we bring together several lines of cross-linguistic research to demonstrate the role of prototypicality in young children’s acquisition of the transitive construction. Much research has shown that young children are slow to form abstract constructions because they fail to see the more general applicability of syntactic markers such as word order and case marking. Here we attempt to explain this fact by investigating the nature of the language children do and do not hear, specifically, the reliability and availability of the linguistic cues they are exposed to. We suggest that constructions redundantly marked with multiple cues could have a special status as a nucleus around which the prototype forms—which makes it difficult for them to isolate the functional significance of each cue. The implications of this view for language acquisition are discussed within a usage-based framework

Measuring category intuitiveness in unconstrained categorization tasks

What makes a category seem natural or intuitive? In this paper, an unsupervised categorization task was employed to examine observer agreement concerning the categorization of nine different stimulus sets. The stimulus sets were designed to capture different intuitions about classification structure. The main empirical index of category intuitiveness was the frequency of the preferred classification, for different stimulus sets. With 169 participants, and a within participants design, with some stimulus sets the most frequent classification was produced over 50 times and with others not more than two or three times. The main empirical finding was that cluster tightness was more important in determining category intuitiveness, than cluster separation. The results were considered in relation to the following models of unsupervised categorization: DIVA, the rational model, the simplicity model, SUSTAIN, an Unsupervised version of the Generalized Context Model (UGCM), and a simple geometric model based on similarity. DIVA, the geometric approach, SUSTAIN, and the UGCM provided good, though not perfect, fits. Overall, the present work highlights several theoretical and practical issues regarding unsupervised categorization and reveals weaknesses in some of the corresponding formal models

Combining prototypes: A selective modification model

We propose a model that accounts for how people construct prototypes for composite concepts out of prototypes for simple concepts. The first component of the model is a prototype representation for simple, noun concepts, such as fruit, which specifies: (1) the relevant attributes of the concepts, (2) the possible values of each attribute, (3) the salience of each value, and (4) the diagnosticity of each attribute. The second component of the model specifies procedures for modifying simple prototypes so that they represent new, composite concepts. The procedure for adjectival modification, as when red modifies fruit, consists of selecting the relevant attribute(s) in the noun concept (color), boosting the diagnosticity of that attribute, and increasing the salience of the value named by the adjective (red). The procedure for adverbial modification, as in very red fruit, consists of multiplication-by-o-scalar of the salience of the relevant value (red). The outcome of these procedures is a new prototype representation. The third component of the model is [Tversky, 1977] contrast rule for determining the similarity between a representation for a prototype and one for an instance. The model is shown to be consistent with previous findings about prototypes in general, as well as with specific findings about typicality judgments for adjective-noun conjunctions. Four new experiments provide further detailed support for the model.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27126/1/0000118.pd

A Developmental Approach to Machine Learning?

Visual learning depends on both the algorithms and the training material. This essay considers the natural statistics of infant- and toddler-egocentric vision. These natural training sets for human visual object recognition are very different from the training data fed into machine vision systems. Rather than equal experiences with all kinds of things, toddlers experience extremely skewed distributions with many repeated occurrences of a very few things. And though highly variable when considered as a whole, individual views of things are experienced in a specific order – with slow, smooth visual changes moment-to-moment, and developmentally ordered transitions in scene content. We propose that the skewed, ordered, biased visual experiences of infants and toddlers are the training data that allow human learners to develop a way to recognize everything, both the pervasively present entities and the rarely encountered ones. The joint consideration of real-world statistics for learning by researchers of human and machine learning seems likely to bring advances in both disciplines

Perceptual-cognitive changes during motor learning: The influence of mental and physical practice on mental representation, gaze behavior, and performance of a complex action

Frank C, Land WM, Schack T. Perceptual-cognitive changes during motor learning: The influence of mental and physical practice on mental representation, gaze behavior, and performance of a complex action. Frontiers in Psychology. 2016;6: 1981.Despite the wealth of research on differences between experts and novices with respect to their perceptual-cognitive background (e.g., mental representations, gaze behavior), little is known about the change of these perceptual-cognitive components over the course of motor learning. In the present study, changes in one’s mental representation, quiet eye behavior, and outcome performance were examined over the course of skill acquisition as it related to physical and mental practice. Novices (N = 45) were assigned to one of three conditions: physical practice, combined physical plus mental practice, and no practice. Participants in the practice groups trained on a golf putting task over the course of 3 days, either by repeatedly executing the putt, or by both executing and imaging the putt. Findings revealed improvements in putting performance across both practice conditions. Regarding the perceptual-cognitive changes, participants practicing mentally and physically revealed longer quiet eye durations as well as more elaborate representation structures in comparison to the control group, while this was not the case for participants who underwent physical practice only. Thus, in the present study, combined mental and physical practice led to both formation of mental representations in long-term memory and longer quiet eye durations. Interestingly, the length of the quiet eye directly related to the degree of elaborateness of the underlying mental representation, supporting the notion that the quiet eye reflects cognitive processing. This study is the first to show that the quiet eye becomes longer in novices practicing a motor action. Moreover, the findings of the present study suggest that perceptual and cognitive adaptations co-occur over the course of motor learning

Fragment-Based Learning of Visual Object Categories in Non-Human Primates

When we perceive a visual object, we implicitly or explicitly associate it with an object category we know. Recent research has shown that the visual system can use local, informative image fragments of a given object, rather than the whole object, to classify it into a familiar category. We have previously reported, using human psychophysical studies, that when subjects learn new object categories using whole objects, they incidentally learn informative fragments, even when not required to do so. However, the neuronal mechanisms by which we acquire and use informative fragments, as well as category knowledge itself, have remained unclear. Here we describe the methods by which we adapted the relevant human psychophysical methods to awake, behaving monkeys and replicated key previous psychophysical results. This establishes awake, behaving monkeys as a useful system for future neurophysiological studies not only of informative fragments in particular, but also of object categorization and category learning in general