Where word and world meet: Language and vision share an abstract representation of symmetry.

Symmetry is ubiquitous in nature, in logic and mathematics, and in perception, language, and thought. Although humans are exquisitely sensitive to visual symmetry (e.g., of a butterfly), symmetry in natural language goes beyond visuospatial properties: many words point to abstract concepts with symmetrical content (e.g., equal, marry). For example, if Mark marries Bill, then Bill marries Mark. In both cases (vision and language), symmetry may be formally characterized as invariance under transformation. Is this a coincidence, or is there some deeper psychological resemblance? Here we asked whether representations of symmetry correspond across language and vision. To do so, we developed a novel cross-modal matching paradigm. On each trial, participants observed a visual stimulus (either symmetrical or nonsymmetrical) and had to choose between a symmetrical and nonsymmetrical English predicate unrelated to the stimulus (e.g., "negotiate" vs. "propose"). In a first study with visual events (symmetrical collision or asymmetrical launch), participants reliably chose the predicate matching the event's symmetry. A second study showed that this "language-vision correspondence" generalized to objects and was weakened when the stimuli's binary nature was made less apparent (i.e., for one object, rather than two inward-facing objects). A final study showed the same effect when nonsigners guessed English translations of signs from American Sign Language, which expresses many symmetrical concepts spatially. Taken together, our findings support the existence of an abstract representation of symmetry which humans access via both perceptual and linguistic means. More broadly, this work sheds light on the rich, structured nature of the language-cognition interface. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Recollecting What We Once Knew: My Life in Psycholinguistics.

The mid-twentieth century brought a radical change in how the linguistics community formulated its major goal, moving from a largely taxonomic science to Chomsky's revolution, which conceptualized language as a higher-order cognitive function. This article reviews the paths (not always direct) that brought Lila Gleitman into contact with that revolution, her contributions to it, and the evolution in her thinking about how language is learned by every child, regardless of extreme variation in the input received. To understand how that occurs, we need to discover what must be learned by the child and what is already there to guide that learning-what must be, in Plato's terms, "recollected." The growing picture shows a learner equipped with information-processing mechanisms that extract evidence about word meanings using various evidential sources. Chief among these are the observational and linguistic-syntactic contexts in which words occur. The former is supported by a mechanism Gleitman and her collaborators call "propose but verify," and the latter by a mechanism known as "syntactic boot-strapping."

The violin case.

Three humorous episodes, reproduced here, illustrate debates that played out on the pages of Cognition under the aegis of its founding editor, Jacques Mehler. These are the formal structure of language, the mechanisms by which speech unfolds in time, and the constrained creativity of ordinary language use.

Easy Words: Reference Resolution in a Malevolent Referent World.

This article describes early stages in the acquisition of a first vocabulary by infants and young children. It distinguishes two major stages, the first of which operates by a stand-alone word-to-world pairing procedure and the second of which, using the evidence so acquired, builds a domain-specific syntax-sensitive structure-to-world pairing procedure. As we show, the first stage of learning is slow, restricted in character, and to some extent errorful, whereas the second procedure is determinative, rapid, and essentially errorless. Our central claim here is that the early, referentially based learning procedure succeeds at all because it is reined in by attention-focusing properties of word-to-world timing and related indicants of referential intent.

Structural cues for symmetry, asymmetry, and non-symmetry in Central Taurus Sign Language.

We investigate how predicates expressing symmetry, asymmetry and non-symmetry are encoded in a newly emerging sign language, Central Taurus Sign Language (CTSL). We find that predicates involving symmetry (i.e., reciprocal and symmetrical actions) differ from those involving asymmetry (i.e., transitive) in their use of the morphological devices investigated here: body segmentation, mirror-image articulators and double perspective. Symmetrical predicates also differ from non-symmetrical ones (i.e., intransitive) in their use of mirror-image configuration. Furthermore, reciprocal actions are temporally sequenced within a linear structure, whereas symmetrical actions are not. Thus, our data reveal that CTSL expresses each type of action with a particular combination of linguistic devices to encode symmetry, asymmetry, and non-symmetry. Furthermore, differences in the use of these devices across age cohorts of CTSL suggest that some have become more conventionalized over time. The same semantic distinctions have been observed - though with different realization - in another emerging sign language, Nicaraguan Sign Language (NSL). This converging suggests that natural human language learning capacities include an expectation to distinguish symmetry, asymmetry and non-symmetry.

The emergence of the formal category "symmetry" in a new sign language.

Logical properties such as negation, implication, and symmetry, despite the fact that they are foundational and threaded through the vocabulary and syntax of known natural languages, pose a special problem for language learning. Their meanings are much harder to identify and isolate in the child's everyday interaction with referents in the world than concrete things (like spoons and horses) and happenings and acts (like running and jumping) that are much more easily identified, and thus more easily linked to their linguistic labels (spoon, horse, run, jump). Here we concentrate attention on the category of symmetry [a relation R is symmetrical if and only if (iff) for all x, y: if R(x,y), then R(y,x)], expressed in English by such terms as similar, marry, cousin, and near After a brief introduction to how symmetry is expressed in English and other well-studied languages, we discuss the appearance and maturation of this category in Nicaraguan Sign Language (NSL). NSL is an emerging language used as the primary, daily means of communication among a population of deaf individuals who could not acquire the surrounding spoken language because they could not hear it, and who were not exposed to a preexisting sign language because there was none available in their community. Remarkably, these individuals treat symmetry, in both semantic and syntactic regards, much as do learners exposed to a previously established language. These findings point to deep human biases in the structures underpinning and constituting human language.

The Pursuit of Word Meanings.

We evaluate here the performance of four models of cross-situational word learning: two global models, which extract and retain multiple referential alternatives from each word occurrence; and two local models, which extract just a single referent from each occurrence. One of these local models, dubbed Pursuit, uses an associative learning mechanism to estimate word-referent probability but pursues and tests the best referent-meaning at any given time. Pursuit is found to perform as well as global models under many conditions extracted from naturalistic corpora of parent-child interactions, even though the model maintains far less information than global models. Moreover, Pursuit is found to best capture human experimental findings from several relevant cross-situational word-learning experiments, including those of Yu and Smith (), the paradigm example of a finding believed to support fully global cross-situational models. Implications and limitations of these results are discussed, most notably that the model characterizes only the earliest stages of word learning, when reliance on the co-occurring referent world is at its greatest.

Two- and three-year-olds track a single meaning during word learning: Evidence for Propose-but-verify.

A child word-learning experiment is reported that examines 2- and 3-year-olds' ability to learn the meanings of novel words across multiple, referentially ambiguous, word occurrences. Children were told they were going on an animal safari in which they would learn the names of unfamiliar animals. Critical trial sequences began with hearing a novel word (e.g., "I see a dax! Point to the dax!") while seeing photos of two unfamiliar animals. After responding and performing on two filler trials with known animals, participants encountered the novel word again ("I see another dax! Point to the dax!") in one of two experimental conditions. In the Same condition, participants saw the animal they pointed to previously when hearing "dax" alongside another unfamiliar animal that had been seen before but not paired with "dax". In the Switch condition, participants saw the animal they had not pointed to previously alongside the unfamiliar animal. Children were well above chance on Same trials, but at chance on Switch trials. Thus, although children could remember a previously selected referent and use it to inform later referent selection (Same condition), a potential referent that was not previously selected and merely co-occurred with the target word (Switch condition) was either not remembered, or simply deemed irrelevant to word meaning. This finding suggests young children do not store multiple possible meanings from a single word occurrence, but rather restrict learning to what they deemed to be the unique referent of the novel word in the moment, testing that word-meaning hypothesis on the next occurrence.

Semantic ambiguity and syntactic bootstrapping: The case of conjoined-subject intransitive sentences.

When learning verb meanings, learners capitalize on universal linguistic correspondences between syntactic and semantic structure. For instance, upon hearing the transitive sentence "the boy is glorping the girl" two-year olds prefer a two-participant event (e.g., a boy making a girl spin) over two simultaneous one-participant events (a boy and a girl separately spinning). However, two- and three-year-olds do not consistently show the opposite preference when hearing conjoined-subject intransitive sentences ("the boy and the girl are glorping"). We hypothesized that such difficulties arise in part from the indeterminacy of the mapping between intransitive syntax and events in the world: a conjoined-subject intransitive sentence can be matched by the one-participant event (if "glorp" means "spin"), both events ("play"), or even the two-participant event ("fight"). A preferential looking study provided evidence for this hypothesis: sentences that plausibly block most non-target interpretations for novel verbs ("the boy and the umbrella are glorping") eliminated the asymmetric difficulty associated with conjoined-subject intransitives. Thus, while conjoined-subject intransitives clearly pose some special challenges for syntax-guided word learning ("syntactic bootstrapping") by novices (Gertner & Fisher, 2012), children's difficulties with this sentence type also reflect expected performance in situations of semantic ambiguity. In discussion, we consider the interacting effects of syntactic- and message-level indeterminacy.

Perceiving referential intent: Dynamics of reference in natural parent-child interactions.

Two studies are presented which examined the temporal dynamics of the social-attentive behaviors that co-occur with referent identification during natural parent-child interactions in the home. Study 1 focused on 6.2 h of videos of 56 parents interacting during everyday activities with their 14-18 month-olds, during which parents uttered common nouns as parts of spontaneously occurring utterances. Trained coders recorded, on a second-by-second basis, parent and child attentional behaviors relevant to reference in the period (40 s) immediately surrounding parental naming. The referential transparency of each interaction was independently assessed by having naïve adult participants guess what word the parent had uttered in these video segments, but with the audio turned off, forcing them to use only non-linguistic evidence available in the ongoing stream of events. We found a great deal of ambiguity in the input along with a few potent moments of word-referent transparency; these transparent moments have a particular temporal signature with respect to parent and child attentive behavior: it was the object's appearance and/or the fact that it captured parent/child attention at the moment the word was uttered, not the presence of the object throughout the video, that predicted observers' accuracy. Study 2 experimentally investigated the precision of the timing relation, and whether it has an effect on observer accuracy, by disrupting the timing between when the word was uttered and the behaviors present in the videos as they were originally recorded. Disrupting timing by only ±1 to 2 s reduced participant confidence and significantly decreased their accuracy in word identification. The results enhance an expanding literature on how dyadic attentional factors can influence early vocabulary growth. By hypothesis, this kind of time-sensitive data-selection process operates as a filter on input, removing many extraneous and ill-supported word-meaning hypotheses from consideration during children's early vocabulary learning.

Quality of early parent input predicts child vocabulary 3 years later.

Children vary greatly in the number of words they know when they enter school, a major factor influencing subsequent school and workplace success. This variability is partially explained by the differential quantity of parental speech to preschoolers. However, the contexts in which young learners hear new words are also likely to vary in referential transparency; that is, in how clearly word meaning can be inferred from the immediate extralinguistic context, an aspect of input quality. To examine this aspect, we asked 218 adult participants to guess 50 parents' words from (muted) videos of their interactions with their 14- to 18-mo-old children. We found systematic differences in how easily individual parents' words could be identified purely from this socio-visual context. Differences in this kind of input quality correlated with the size of the children's vocabulary 3 y later, even after controlling for differences in input quantity. Although input quantity differed as a function of socioeconomic status, input quality (as here measured) did not, suggesting that the quality of nonverbal cues to word meaning that parents offer to their children is an individual matter, widely distributed across the population of parents.

Propose but verify: fast mapping meets cross-situational word learning.

We report three eyetracking experiments that examine the learning procedure used by adults as they pair novel words and visually presented referents over a sequence of referentially ambiguous trials. Successful learning under such conditions has been argued to be the product of a learning procedure in which participants provisionally pair each novel word with several possible referents and use a statistical-associative learning mechanism to gradually converge on a single mapping across learning instances [e.g., Yu, C., & Smith, L. B. (2007). Rapid word learning under uncertainty via cross-situational statistics. Psychological Science, 18(5), 414-420]. We argue here that successful learning in this setting is instead the product of a one-trial procedure in which a single hypothesized word-referent pairing is retained across learning instances, abandoned only if the subsequent instance fails to confirm the pairing--more a 'fast mapping' procedure than a gradual statistical one. We provide experimental evidence for this propose-but-verify learning procedure via three experiments in which adult participants attempted to learn the meanings of nonce words cross-situationally under varying degrees of referential uncertainty. The findings, using both explicit (referent selection) and implicit (eye movement) measures, show that even in these artificial learning contexts, which are far simpler than those encountered by a language learner in a natural environment, participants do not retain multiple meaning hypotheses across learning instances. As we discuss, these findings challenge 'gradualist' accounts of word learning and are consistent with the known rapid course of vocabulary learning in a first language.

How words can and cannot be learned by observation.

Three experiments explored how words are learned from hearing them across contexts. Adults watched 40-s videotaped vignettes of parents uttering target words (in sentences) to their infants. Videos were muted except for a beep or nonsense word inserted where each "mystery word" was uttered. Participants were to identify the word. Exp. 1 demonstrated that most (90%) of these natural learning instances are quite uninformative, whereas a small minority (7%) are highly informative, as indexed by participants' identification accuracy. Preschoolers showed similar information sensitivity in a shorter experimental version. Two further experiments explored how cross-situational information helps, by manipulating the serial ordering of highly informative vignettes in five contexts. Response patterns revealed a learning procedure in which only a single meaning is hypothesized and retained across learning instances, unless disconfirmed. Neither alternative hypothesized meanings nor details of past learning situations were retained. These findings challenge current models of cross-situational learning which assert that multiple meaning hypotheses are stored and cross-tabulated via statistical procedures. Learners appear to use a one-trial "fast-mapping" procedure, even under conditions of referential uncertainty.

Spatial reasoning in Tenejapan Mayans.

Language communities differ in their stock of reference frames (coordinate systems for specifying locations and directions). English typically uses egocentrically-defined axes (e.g., "left-right"), especially when describing small-scale relationships. Other languages such as Tseltal Mayan prefer to use geocentrically-defined axes (e.g., "north-south") and do not use any type of projective body-defined axes. It has been argued that the availability of specific frames of reference in language determines the availability or salience of the corresponding spatial concepts. In four experiments, we explored this hypothesis by testing Tseltal speakers' spatial reasoning skills. Whereas most prior tasks in this domain were open-ended (allowing several correct solutions), the present tasks required a unique solution that favored adopting a frame-of-reference that was either congruent or incongruent with what is habitually lexicalized in the participants' language. In these tasks, Tseltal speakers easily solved the language-incongruent problems, and performance was generally more robust for these than for the language-congruent problems that favored geocentrically-defined coordinates. We suggest that listeners' probabilistic inferences when instruction is open to more than one interpretation account for why there are greater cross-linguistic differences in the solutions to open-ended spatial problems than to less ambiguous ones.

Use of Speaker's Gaze and Syntax in Verb Learning.

Speaker eye gaze and gesture are known to help child and adult listeners establish communicative alignment and learn object labels. Here we consider how learners use these cues, along with linguistic information, to acquire abstract relational verbs. Test items were perspective verb pairs (e.g., chase/flee, win/lose), which pose a special problem for observational accounts of word learning because their situational contexts overlap very closely; the learner must infer the speaker's chosen perspective on the event. Two cues to the speaker's perspective on a depicted event were compared and combined: (a) the speaker's eye gaze to an event participant (e.g., looking at the Chaser vs. looking at the Flee-er) and (b) the speaker's linguistic choice of which event participant occupies Subject position in his utterance. Participants (3-, 4-, and 5-year-olds) were eye-tracked as they watched a series of videos of a man describing drawings of perspective events (e.g., a rabbit chasing an elephant). The speaker looked at one of the two characters and then uttered either an utterance that was referentially uninformative (He's mooping him) or informative (The rabbit's mooping the elephant/The elephant's mooping the rabbit) because of the syntactic positioning of the nouns. Eye-tracking results showed that all participants regardless of age followed the speaker's gaze in both uninformative and informative contexts. However, verb-meaning choices were responsive to speaker's gaze direction only in the linguistically uninformative condition. In the presence of a linguistically informative context, effects of speaker gaze on meaning were minimal for the youngest children to nonexistent for the older populations. Thus children, like adults, can use multiple cues to inform verb-meaning choice but rapidly learn that the syntactic positioning of referring expressions is an especially informative source of evidence for these decisions.

Effect of congenital blindness on the semantic representation of some everyday concepts.

This study explores how the lack of first-hand experience with color, as a result of congenital blindness, affects implicit judgments about "higher-order" concepts, such as "fruits and vegetables" (FV), but not others, such as "household items" (HHI). We demonstrate how the differential diagnosticity of color across our test categories interacts with visual experience to produce, in effect, a category-specific difference in implicit similarity. Implicit pair-wise similarity judgments were collected by using an odd-man-out triad task. Pair-wise similarities for both FV and for HHI were derived from this task and were compared by using cluster analysis and regression analyses. Color was found to be a significant component in the structure of implicit similarity for FV for sighted participants but not for blind participants; and this pattern remained even when the analysis was restricted to blind participants who had good explicit color knowledge of the stimulus items. There was also no evidence that either subject group used color knowledge in making decisions about HHI, nor was there an indication of any qualitative differences between blind and sighted subjects' judgments on HHI.

Why stereotypes don't even make good defaults.

Many concepts have stereotypes. This leaves open the question of whether concepts are stereotypes. It has been argued elsewhere that theories that identify concepts with their stereotypes or with stereotypical properties of their instances (e.g., Rosch, E. (1978). Principles of categorization. In E. Rosch & B. B. Lloyd (Ed.), Cognition and Categorization. Hillsdale, NJ: Lawrence Erlbaum Associates; Smith, E. E., Medin, D. L. (1981). Categories and Concepts. Cambridge, MA: Harvard University Press.) fail to provide an adequate account of the compositionality of concepts (Fodor, J., Lepore, E. (1996). The red herring and the pet fish: Why concepts still cannot be prototypes. Cognition, 58, 253-270.; Fodor, J. (1998). Concepts: Where cognitive science went wrong. New York, NY: Oxford University Press.). This paper extends this argument and reports an experiment suggesting that participants do not assume, even as a default strategy, that complex concepts inherit the stereotypes of their constituents. Thus propositions such as "Baby ducks have webbed feet" were judged to be less likely to be true than propositions like "Ducks have webbed feet." Moreover, manipulation of the type and number of noun phrase modifiers revealed a systematic departure from the unmodified noun's stereotype both with the addition of stereotypical modifiers ("Quacking ducks have webbed feet" versus "Ducks have webbed feet") and with the addition of a second modifier ("Baby Peruvian ducks have webbed feet" versus "Baby ducks have webbed feet"). Thus, in the general case the stereotypical properties of a head noun are systematically discounted when that head noun combines with modifiers. This effect represents a general principle of conceptual combination that argues against the inheritance of stereotypical features of concepts as a default strategy. Instead, we advocate a model of conceptual combination where concepts remain inert under combination, supported by a separate machinery that introduces pragmatic and knowledge-dependent inferences.

When we think about thinking: the acquisition of belief verbs.

Mental-content verbs such as think, believe, imagine and hope seem to pose special problems for the young language learner. One possible explanation for these difficulties is that the concepts that these verbs express are hard to grasp and therefore their acquisition must await relevant conceptual development. According to a different, perhaps complementary, proposal, a major contributor to the difficulty of these items lies with the informational requirements for identifying them from the contexts in which they appear. The experiments reported here explore the implications of these proposals by investigating the contribution of observational and linguistic cues to the acquisition of mental predicate vocabulary. We first demonstrate that particular observed situations can be helpful in prompting reference to mental contents, specifically, contexts that include a salient and/or unusual mental state such as a false belief. We then compare the potency of such observational support to the reliability of alternate or concomitant syntactic information (e.g., sentential complementation) in tasks where both children and adults are asked to hypothesize the meaning of novel verbs. The findings support the efficacy of false belief situations for increasing the saliency of mental state descriptions, but also show that syntactic information is a more reliable indicator of mentalistic interpretations than even the most cooperative contextual cues. Moreover, when syntactic and observational information sources converge, both children and simulated adult learners are vastly more likely to build conjectures involving mental verbs. This is consistent with a multiple-cue constraint satisfaction view of vocabulary acquisition. Taken together, our findings support the position that the informational demands of mapping, rather than age-related cognitive deficiency, can bear much of the explanatory burden for the learning problems posed by abstract words.

On the give and take between event apprehension and utterance formulation.

Two experiments are reported which examine how manipulations of visual attention affect speakers' linguistic choices regarding word order, verb use and syntactic structure when describing simple pictured scenes. Experiment 1 presented participants with scenes designed to elicit the use of a perspective predicate (The man chases the dog/The dog flees from the man) or a conjoined noun phrase sentential Subject (A cat and a dog/A dog and a cat). Gaze was directed to a particular scene character by way of an attention-capture manipulation. Attention capture increased the likelihood that this character would be the sentential Subject and altered the choice of perspective verb or word order within conjoined NP Subjects accordingly. Experiment 2 extended these results to word order choice within Active versus Passive structures (The girl is kicking the boy/The boy is being kicked by the girl) and symmetrical predicates (The girl is meeting the boy/The boy is meeting the girl). Experiment 2 also found that early endogenous shifts in attention influence word order choices. These findings indicate a reliable relationship between initial looking patterns and speaking patterns, reflecting considerable parallelism between the on-line apprehension of events and the on-line construction of descriptive utterances.

When English proposes what Greek presupposes: the cross-linguistic encoding of motion events.

How do we talk about events we perceive? And how tight is the connection between linguistic and non-linguistic representations of events? To address these questions, we experimentally compared motion descriptions produced by children and adults in two typologically distinct languages, Greek and English. Our findings confirm a well-known asymmetry between the two languages, such that English speakers are overall more likely to include manner of motion information than Greek speakers. However, mention of manner of motion in Greek speakers' descriptions increases significantly when manner is not inferable; by contrast, inferability of manner has no measurable effect on motion descriptions in English, where manner is already preferentially encoded. These results show that speakers actively monitor aspects of event structure, which do not find their way into linguistic descriptions. We conclude that, in regard to the differential encoding of path and manner, which has sometimes been offered as a prime example of the effects of language encoding on non-linguistic thought, surface linguistic encoding neither faithfully represents nor strongly constrains our mental representation of events.