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H Gleitman

Publications and source records attributed to H Gleitman.

10 recordsLinked to original sources
PubMed1999

Human simulations of vocabulary learning.

The work reported here experimentally investigates a striking generalization about vocabulary acquisition: Noun learning is superior to verb learning in the earliest moments of child language development. The dominant explanation of this phenomenon in the literature invokes differing conceptual requirements for items in these lexical categories: Verbs are cognitively more complex than nouns and so their acquisition must await certain mental developments in the infant. In the present work, we investigate an alternative hypothesis; namely, that it is the information requirements of verb learning, not the conceptual requirements, that crucially determine the acquisition order. Efficient verb learning requires access to structural features of the exposure language and thus cannot take place until a scaffolding of noun knowledge enables the acquisition of clause-level syntax. More generally, we experimentally investigate the hypothesis that vocabulary acquisition takes place via an incremental constraint-satisfaction procedure that bootstraps itself into successively more sophisticated linguistic representations which, in turn, enable new kinds of vocabulary learning. If the experimental subjects were young children, it would be difficult to distinguish between this information-centered hypothesis and the conceptual change hypothesis. Therefore the experimental "learners" are adults. The items to be "acquired" in the experiments were the 24 most frequent nouns and 24 most frequent verbs from a sample of maternal speech to 18-24-month-old infants. The various experiments ask about the kinds of information that will support identification of these words as they occur in mother-to-child discourse. Both the proportion correctly identified and the type of word that is identifiable changes significantly as a function of information type. We discuss these results as consistent with the incremental construction of a highly lexicalized grammar by cognitively and pragmatically sophisticated human infants, but inconsistent with a procedure in which lexical acquisition is independent of and antecedent to syntax acquisition.

Adult↗
PubMed1996

Similar, and similar concepts.

This paper analyzes English symmetrical predicates such as collide and match. Its point of departure is an analysis of the concept 'similar' from Tversky (1977) that appears to show that similarity is psychologically asymmetrical. One basis for this claim from Tversky is that the sentences North Korea is similar to Red China and Red China is similar to North Korea are assessed as differing in meaning by experimental subjects; this seems to imply that the symmetrical entailment (R x, y <--> R y, x) fails for this concept. Five experiments are presented that show: (1) the apparent asymmetry of similar is reproduced for 20 predicates that are intuitively thought to be symmetrical, including equal and identical; (2) unique linguistic-interpretative properties hold for these symmetrical words, such as reciprocal interpretation when they appear intransitively, for example, North Korea and Red China are similar; (3) the asymmetrical interpretation of subject-complement constructions containing the symmetrical words is a consequence of general linguistic-interpretive principles. On the basis of the experimental findings, we offer an analysis of symmetrical predication. One major claim of the analysis is that symmetry is a property of lexical items and has no special syntax, that is, that John meets is semantically but not syntactically anomalous. A second claim is that the structural positioning of noun phrases in sentences containing symmetricals--rather than inherent semantic properties of the noun phrases themselves--sets their status as Figure and Ground (as described by Talmy, 1985) or Variant and Referent (as described by Tversky, 1977) in the comparison, even if the nouns are nonsense items. Finally, the behavior of symmetrical predicates is shown to vary as a function of their differing lexical class assignments and collateral semantic designations, such as activity versus state. Most generally, it is claimed that a deeper understanding of symmetrical terms comes from analyzing the semantics of syntactic structures in which they appear.

Humans↗
PubMed1991

On the semantic content of subcategorization frames.

This paper investigates relations between the meanings of verbs and the syntactic structures in which they appear. This investigation is motivated by the enigmas as to how children discover verb meanings. Well-known problems with unconstrained induction of word meanings from observation of world circumstances suggest that additional constraints or sources of information are required. If there exist strong and reliable parallels between the structural and semantic properties of verbs, then an additional source of information about verb meanings is reliably present in each verb's linguistic context. Five experiments are presented which investigate the following hypothesis regarding the scope of these relations: The closer any two verbs in their semantic structure, the greater the overlap should be in their licensed syntactic structures. To investigate this hypothesis, data of two kinds were collected from different groups of subjects: (a) One group of subjects was asked to judge the semantic relatedness of verbs by selecting the semantic outlier in triads presented to them. (b) A second group of subjects was asked to judge the grammaticality of these same verbs in a large range of syntactic environments. These two types of data were then compared to assess the degree of correspondence in the two partitionings (syntactic and semantic) of the verb set. The findings, overall, support the view that the syntax of verbs is a quite regular, although complex, projection from their semantics. In conclusion, we discuss the kinds of features that are formally marked in syntactic structure and relate these to the problem of verb-vocabulary acquisition in young children.

Concept Formation↗
PubMed1987

Perceptual completion of surfaces in infancy.

Two experiments provide evidence that 4-month-old infants perceive background surfaces as continuous behind occluding objects. Infants were shown a partly hidden background surface either for a brief period of familiarization (Experiment 1) or until they met a criterion of habituation (Experiment 2). The infants were then tested with nonoccluded surfaces that were either continuous or interrupted by a gap where the occluder had been. The infants in each study looked longer at the interrupted than at the continuous surface, relative to infants in baseline controls, which suggests that the partly hidden surface was perceived as continuous. Contrasting findings were obtained in a third experiment, in which infants were habituated to a partly hidden surface that stood in front of a background so that its edges were visible: Infants gave no evidence of perceiving the foreground surface as continuous behind the occluder. These experiments provide evidence that infants perceive a surface as continuous only if it serves as the background of a scene. The results are discussed in relation to figure-ground perception in pictures and surface layouts.

Female↗
PubMed1987

Object and observer motion in the perception of objects by infants.

Sixteen-week-old human infants distinguish optical displacements given by their own motion from displacements given by moving objects, and they use only the latter to perceive the unity of partly occluded objects. Optical changes produced by moving the observer around a stationary object produced attentional levels characteristic of stationary observers viewing stationary displays and much lower than those shown by stationary observers viewing moving displays. Real displacements of an object with no subject-relative displacement, produced by moving an object so as to maintain a constant relation to the moving observer, evoked attentional levels that were higher than with stationary displays and more characteristic of attention to moving displays, a finding suggesting detection of the real motion. Previously reported abilities of infants to perceive the unity of partly occluded objects from motion information were found to depend on real object motion rather than on optical displacements in general. The results suggest that object perception depends on registration of the motions of surfaces in the three-dimensional layout.

Attention↗
PubMed1981

Spatial knowledge and geometric representation in a child blind from birth.

A series of experiments demonstrated that a congenitally blind 2 1/2-year-old child-as well as sighted but blindfolded children and adults-can determine the appropriate path between two objects after traveling to each of those objects from a third object. This task requires that the child detect the distances and the angular relationship of the familiar paths and that she derive therefrom the angle of the new path. Our research indicates that the locomotion of the young blind child is guided by knowledge of the Euclidean properties of a spatial layout and by principles for making inferences based on those properties.

Auditory Perception↗