Structural Alignment during Similarity Comparisons

Similarity comparisons are a basic component of cognition, and there are many elegant models of this process. None of these models describe comparisons of structured representations, although mounting evidence suggests that mental representations are well characterized by structured hierarchical systems of relations. We propose that structured representations can be compared via structural alignment, a process derived from models of analogical reasoning. The general prediction of structural alignment is that similarity comparisons lead subjects to attend to the matching relational structure in a pair of items. This prediction is illustrated with a computational simulation that also suggests that the strength of the relational focus is diminished when the relational match is impoverished, or when competing interpretations lead to rich object matches. These claims are tested in four experiments using the one-shot mapping paradigm, which places object similarity and relational similarity in opposition. The results support the hypothesis that similarity involves the alignment of structured representations.     

THE EFFECTS OF ALIGNABILITY ON MEMORY

Abstract— According to structure-mapping theory, the process of comparison in one of alignment and mapping between representational structures. This process induces a focus on commonalities and alignable differences (i.e., those related to the commonalities). Non-alignable differences (i.e., those not related to the commonalities) are held to be neglected. The theory thus predicts increased focus on the corresponding information, Whether these are commonalities or differences. In this article, we explore the implications of this claim for memory: Specifically, we test the prediction that alignable differences are more likely to be processed and stored than nonalignable differences.
We present a study in which people made similarity comparisons between pairs of pictures and then were probed for recall. The recall probes were figures taken from the pictures and were either alignable or nonalignable differences between the pairs. The alignable differences were better memory probes than the nonalignable differences, suggesting that people were more likely to encode and store the corresponding information than the noncorresponding information.     

Commonalities and differences in similarity comparisons

Similarity is a central component of many cognitive processes. Current research suggests that similarity is well characterized as a comparison of structured representations. This process yields commonalities, differences related to the commonalities (alignable differences), and differences not related to the commonalities (nonalignable differences). In the first study, further evidence for this tripartite distinction is provided in a commonality and difference listing study involving pairs of pictures. This study indicates that alignable differences rather than nonalignable differences are central to the comparison process by virtue of their connection to the commonalities. The second study further demonstrates that alignable differences count more against the similarity of a pair than do nonalignable differences. We end by discussing implications of the distinction between alignable and nonalignable differences for other cognitive processes involving comparisons.     

Verb semantic structures in memory for sentences: Evidence for componential representation

This research contrasts two hypotheses concerning componential storage of meaning. The Complexity Hypothesis assumed by Fodor (The language of thought, NY: Crowell, 1975), Kintsch (The representation of meaning in memory, Hillsdale, NJ: Erlbaum, 1974), and Thorndyke (Conceptual complexity and imagery in comprehension and memory. Journal of Verbal Learning and Verbal Behavior, 1975, 14, 359–369) states that a word with many semantic components will require more processing resources, comprehension time, and long-term memory space than a word with few components, and thus will interfere more with memory for surrounding words. This memory prediction was tested against an alternative prediction based on connectivity. The Connectivity Hypothesis views verb semantic structures as frames for sentence representation and states that memory strength between two nouns in a sentence increases with the number of underlying verb subpredicates that connect the nouns. Thus, the Complexity Hypothesis predicts that a verb with many subpredicates will lead to poorer memory strength between the surrounding nouns than a verb with few subpredicates, while the Connectivity Hypothesis predicts that verbs with many subpredicates will lead to greater memory strength between nouns in cases when the additional subpredicates provide semantic connections between the nouns.In three experiments, subjects recalled subject-verb-object sentences, given subject nouns as cues. General verbs, with relatively few subpredicates, were compared with more specific verbs whose additional subpredicates either did or did not provide additional connections between the surrounding nouns. The level of recall of the object noun, given the subject noun as cue, was predicted by the relative number of connecting subpredicates in the verb, but not by the relative number of subpredicates. This finding supports the Connectivity Hypothesis over the Complexity Hypothesis. These results are interpreted in terms of a model in which the verb conveys a structured set of subpredicates that provides a connective framework for sentence memory.     

Evidence for role-neutral initial processing of metaphors

Two models of metaphor processing are contrasted. The structure-mapping model postulates an initially role-neutral alignment process, followed by directional projection of inferences. The attributive categorization model postulates role-specific processing throughout comprehension. To test between these models, the early stages of metaphor comprehension were probed using a technique based on S. Glucksberg, P. Gildea, and H. Bookin's (1982) finding that metaphorical meaning interferes with literal truthfulness judgments. In Experiment 1, interference effects did not differ between normal metaphors and metaphors with reversed terms, suggesting that initial processing is role-neutral. In Experiment 2, we again found no role dependence in interference effects, even for highly conventional metaphors. In Experiment 3, it was verified that (a) full comprehension is role-sensitive and (b) full comprehension reaction times (RTs) are far longer than interference RTs, buttressing the claim that interference is an early-stage effect. Overall, the results support the structure-mapping model of metaphor processing.     

The career of metaphor

A central question in metaphor research is how metaphors establish mappings between concepts from different domains. The authors propose an evolutionary path based on structure-mapping theory. This hypothesis--the career of metaphor--postulates a shift in mode of mapping from comparison to categorization as metaphors are conventionalized. Moreover, as demonstrated by 3 experiments, this processing shift is reflected in the very language that people use to make figurative assertions. The career of metaphor hypothesis offers a unified theoretical framework that can resolve the debate between comparison and categorization models of metaphor. This account further suggests that whether metaphors are processed directly or indirectly, and whether they operate at the level of individual concepts or entire conceptual domains, will depend both on their degree of conventionality and on their linguistic form.     

Comparison in the Development of Categories

Recent research on children's word learning has led to a paradox. Although word learning appears to be a deep source of insight into conceptual knowledge for children, preschoolers often categorize objects on the basis of shallow perceptual features such as shape. The current studies seek to resolve this discrepancy. We suggest that comparing multiple instances of a category enables children to extract deeper relational commonalities among category members. We examine 4-year-olds' categorization behaviors when asked to select a match for a target object (e.g., an apple) between a perceptually similar, out-of-kind object (e.g., a balloon) and a perceptually different category match (e.g., a banana). Children who learn a novel word as a label for multiple instances of the category are more likely to select the category match over the perceptual match. Children who learn a label for only one instance are equally likely to select either alternative. This effect is present even when individual target instances are more perceptually similar to the perceptual choice than to the category choice. We conclude that structural alignment processes may be important in the development of category understanding.     

Well‐Hidden Regularities: Abstract Uses of in and on Retain an Aspect of Their Spatial Meaning

Prepositions name spatial relationships (e.g., book on a table). But they are also used to convey abstract, non‐spatial relationships (e.g., Adrian is on a roll)—raising the question of how the abstract uses relate to the concrete spatial uses. Despite considerable success in delineating these relationships, no general account exists for the two most frequently extended prepositions: in and on. We test the proposal that what is preserved in abstract uses of these prepositions is the relative degree of control between the located object (the figure) and the reference object (the ground). Across four experiments, we find a continuum of greater figure control for on (e.g., Jordan is on a roll) and greater ground control for in (e.g., Casey is in a depression). These findings bear on accounts of semantic structure and language change, as well as on second language instruction.     

Distributed recognition of natural songs by European starlings

Individual vocal recognition behaviors in songbirds provide an excellent framework for the investigation of comparative psychological and neurobiological mechanisms that support the perception and cognition of complex acoustic communication signals. To this end, the complex songs of European starlings have been studied extensively. Yet, several basic parameters of starling individual vocal recognition have not been assessed. Here we investigate the temporal extent of song information acquired by starlings during vocal recognition learning. We trained two groups of starlings using standard operant conditioning techniques to recognize several songs from two conspecific male singers. In the first experiment we tested their ability to maintain accurate recognition when presented with (1) random sequences of 1–12 motifs (stereotyped song components) drawn from the training songs, and (2) 0.1–12-s excerpts of continuous song drawn from the training songs. We found that song recognition improved monotonically as more vocal material is provided. In the second experiment, we systematically substituted continuous, varying length regions of white noise for portions of the training songs and again examined recognition accuracy. Recognition remained above chance levels for all noise substitutions tested (up to 91% of the training stimulus) although all but the smallest substitutions led to some decrement in song recognition. Overall, above chance recognition could be obtained with surprisingly few motifs, short excerpts of song, and in the absence of large portions of the training songs. These results suggest that starlings acquire a representation of song during individual vocal recognition learning that is robust to perturbations and distributed broadly over large portions of these complex acoustic sequences.     

Comparison Facilitates Children's Learning of Names for Parts

Learning names for parts of objects can be challenging for children, as it requires overcoming their tendency to name whole objects. We test whether comparing items can facilitate learning names for their parts. Applying the structure-mapping theory of comparison leads to two predictions: (a) young children will find it easier to identify a common part between two very similar items than between two dissimilar items (because the similar pair is easier to align); (b) close alignments potentiate far alignments: children will be better able to extend a novel part name to a dissimilar object after having extended it to a similar object. In three studies, 227 preschool children mapped novel part terms to new animals or objects. Both predictions were confirmed. Children more accurately extended novel part terms to objects that were similar to the standard than to objects that were dissimilar (Experiments 1 and 2), and children more accurately extended novel part names to dissimilar objects after having extended them to similar objects (Experiment 3). We conclude that structure-mapping processes can support part learning.