Featural Similarity Research Articles

An Empirical Investigation of Featural Similarity in Wh-islands

According to the most recent version of Relativized Minimality, the ungrammaticality of weak islands is the result of featural similarity between elements in an intervention configuration. The theory posits that only features triggering movement have the potential to induce intervention effects leading to ungrammaticality. However, recent advancements in the theory have extended the set of features claimed to generate intervention effects to encompass lexical restriction. This theoretical move encounters several empirical challenges. In this paper, we address this question in 3 acceptability judgment experiments in French. We explore how featural similarity influences acceptability judgments across both wh-islands and minimally different grammatical structures, that-clauses extraction, focusing on three distinct features: (i) the feature associated with question operators, (ii) lexical restriction, both anticipated to show intervention effects according to the most recent version of Relativized Minimality, and (iii) animacy, which is not expected to show such effects. Results indicate that featural similarity in lexical restriction and animacy exerts a mild influence on acceptability ratings in both islands and grammatical structures, contrary to what predicted by Relativized Minimality, while similarity in the feature associated with question operators exerts a strong influence. We propose an empirically motivated account that restricts the set of features relevant to grammar-based effects à la Relativized Minimality to core syntactic features triggering movement, and groups together the milder effects arising from similarity in other linguistic features, like lexical restriction and animacy, as resulting from similarity-based interference in memory.

Similarity and structured representation in human and nonhuman apes

How we judge the similarity between objects in the world is connected ultimately to how we represent those objects. It has been argued extensively that object representations in humans are ‘structured’ in nature, meaning that both individual features and the relations between them can influence similarity. In contrast, popular models within comparative psychology assume that nonhuman species appreciate only surface-level, featural similarities. By applying psychological models of structural and featural similarity (from conjunctive feature models to Tversky's Contrast Model) to visual similarity judgements from adult humans, chimpanzees, and gorillas, we demonstrate a cross-species sensitivity to complex structural information, particularly for stimuli that combine colour and shape. These results shed new light on the representational complexity of nonhuman apes, and the fundamental limits of featural coding in explaining object representation and similarity, which emerge strikingly across both human and nonhuman species.

Construction-specific effects of phonological similarity avoidance

AbstractPrevious research on similarity avoidance has focused on such phonological factors as featural similarity and adjacency. This paper additionally investigates the phonology-morphology interface and draws attention to morphological and lexical effects of similarity avoidance. Avoidance of identical or similar sounds may give rise to a variety of strategies, including periphrastic category formation, an unexpected allomorph of the stem or affix and a lexical gap. It is argued that, although similarity avoidance has a universal basis in language processing, the various strategies to implement it are construction specific. In particular, it is shown that one construction may exhibit a different scope of OCP effects than another, which entails that the constraints regulating OCP effects should be morphosyntactically indexed, in turn requiring reference to multiple cophonologies with distinct properties. A novel finding is that cophonologies may be delimited by the syntactic category of the base of category formation. Drawing on the insight of Construction Morphology, the analysis represents dissimilation as an interaction of construction-specific OCP constraints with schemas that include reference to the base. In order to derive the gradience of OCP effects, the relevant constraints are ranked on the basis of a similarity metric and formal complexity. The proposed constraint-based analysis aims to represent the construction-specific strategies for dealing with dissimilation and capture the observed gradience of the pressure.

Typicality guides attention during categorical search, but not universally so.

The degree to which an item is rated as being a typical member of its category influences an observer's ability to find that item during word-cued search. However, there are conflicting accounts as to whether or not typicality affects attentional guidance to categorical items, or whether it affects some other aspect of the search process. In this study, we employed word-cued search and eye tracking to disentangle typicality effects on attentional guidance and target verification across differing category cue specificities (i.e., superordinate or basic-level cues), while also varying the degree of similarity between targets and non-targets. We found that typicality influenced attentional guidance when searchers were cued at the superordinate level (e.g., clothing). When cues were provided at the basic level (e.g., pants), typicality did not influence attentional guidance, and only affected target verification when there was featural similarity between targets and non-targets. When a searcher uses a target template comprising features cued at the basic level, therefore, target/non-target similarity produces interference that affects attentional guidance, but we did not find evidence that it also affects target verification.

Similarity judgments predict N400 amplitude differences between taxonomic category members and thematic associates

Human similarity judgments do not reliably conform to the predictions of leading theories of psychological similarity. Evidence from the triad similarity judgment task shows that people often identify thematic associates like dog and bone as more similar than taxonomic category members like dog and cat, even though thematic associates lack the type of featural or relational similarity that is foundational to theories of psychological similarity. This specific failure to predict human behavior has been addressed as a consequence of education and other individual differences, an artifact of the triad similarity judgment paradigm, or a shortcoming in psychological accounts of similarity. We investigated the judged similarity of semantically-related concepts (taxonomic category members and thematic associates) as it relates to other task-independent measures of semantic knowledge and access. Participants were assessed on reading and language ability, then event-related potentials (ERPs) were collected during a passive, sequential word reading task that presented pseudowords and taxonomically-related, thematically-related, and unrelated word sequences, and, finally, similarity judgments were collected with the classic two-alternative forced-choice triad task. The results uncovered a correspondence between ERP amplitude and triad-based similarity judgments—similarity judgment behavior reliably predicts ERP amplitude during passive word reading, absent of any instruction to consider similarity. It was also found that individual differences in reading and language ability independently predicted ERP amplitude. This evidence suggests that similarity judgments are driven by reliable patterns of thought that are not solely rooted in the interpretation of task goals or reading and language ability.

Recognition memory and featural similarity between concepts: The pupil’s point of view

Differences in pupil dilation are observed for studied compared to new items in recognition memory. According to cognitive load theory, this effect reflects the greater cognitive demands of retrieving contextual information from study phase. Pupil dilation can also occur when new items conceptually related to old ones are erroneously recognized as old, but the aspects of similarity that modulate false memory and related pupil responses remain unclear. We investigated this issue by manipulating the degree of featural similarity between new (unstudied) and old (studied) concepts in an old/new recognition task. We found that new concepts with high similarity were mistakenly identified as old and had greater pupil dilation than those with low similarity, suggesting that pupil dilation reflects the strength of evidence on which recognition judgments are based and, importantly, greater locus coeruleus and prefrontal activity determined by the higher degree of retrieval monitoring involved in recognizing these items.

Grouping by feature of cross-modal flankers in temporal ventriloquism

Signals in one sensory modality can influence perception of another, for example the bias of visual timing by audition: temporal ventriloquism. Strong accounts of temporal ventriloquism hold that the sensory representation of visual signal timing changes to that of the nearby sound. Alternatively, underlying sensory representations do not change. Rather, perceptual grouping processes based on spatial, temporal, and featural information produce best-estimates of global event properties. In support of this interpretation, when feature-based perceptual grouping conflicts with temporal information-based in scenarios that reveal temporal ventriloquism, the effect is abolished. However, previous demonstrations of this disruption used long-range visual apparent-motion stimuli. We investigated whether similar manipulations of feature grouping could also disrupt the classical temporal ventriloquism demonstration, which occurs over a short temporal range. We estimated the precision of participants’ reports of which of two visual bars occurred first. The bars were accompanied by different cross-modal signals that onset synchronously or asynchronously with each bar. Participants’ performance improved with asynchronous presentation relative to synchronous - temporal ventriloquism - however, unlike the long-range apparent motion paradigm, this was unaffected by different combinations of cross-modal feature, suggesting that featural similarity of cross-modal signals may not modulate cross-modal temporal influences in short time scales.

Mental Files: an Introduction

In the first part of this editorial, we introduce to the topic of the special issue from the perspective of the three main disciplines that have appealed to the mental file construct: psychology, philosophy, and linguistics. In the second part we present the individual contributions to the issue, in connection with the various themes mentioned in the first part. 1. Mental files in psychology, philosophy, and linguistics 1.1. Object files The notion of an object file is used in psychology to characterize visual representations of objects at an intermediate level between low level processing of sensory features and high-level placement of objects in conceptual categories or kinds. The object filing system supports the individuation and tracking of particulars, while allowing information about their features to be stored, updated, and retrieved. It has to decide when visually encountered elements should be counted as different stages of the same persisting object, and so should be assigned the same file, and when not. A signature trait of the object filing system is that the features that matter to its operations are primarily spatiotemporal, rather than qualitative. Flombaum, Scholl, Santos (2009) dub the principle according to which, for object files, spatiotemporal factors take priority over featural similarity the 'principle of spatiotemporal priority'. They argue that it constitutes a 'fundamental principle of object persistence' in human vision. A simple demonstration is the well-known 'tunnel effect' (Burke 1952). If the time it takes an object to disappear then reappear from behind an occluder is roughly the same as the time it would take an object to travel behind the occluder, and if the object's way of moving is appropriate, viewers irresistibly experience a single persisting object, which is temporarily hidden behind the occluder. This is the case even when the reappearing object has very different surface qualities from the disappearing one-for example, a yellow ball can be perceived to 'morph' into a red cup. This experience as of one single persisting object is characteristically encapsulated, or resistant to influence from higher-level judgments of identity, which suggests that it is a perceptual effect. * Authors listed in alphabetical order.

The Influence of Presentation Order on Category Transfer.

This study of supervised categorization shows how different kinds of category representations are influenced by the order in which training examples are presented. We used the well-studied 5-4 category structure of Medin and Schaffer (1978) , which allows transfer of category learning to new stimuli to be discriminated as a function of rule-based or similarity-based category knowledge. In the rule-based training condition (thought to facilitate the learning of abstract logical rules and hypothesized to produce rule-based classification), items were grouped by subcategories and randomized within each subcategory. In the similarity-based training condition (thought to facilitate associative learning and hypothesized to produce exemplar classification), transitions between items within the same category were determined by their featural similarity and subcategories were ignored. We found that transfer patterns depended on whether the presentation order was similarity-based, or rule-based, with the participants particularly capitalizing on the rule-based order.

The organization of words and environmental sounds in memory

In the present study we used event-related potentials to compare the organization of linguistic and meaningful nonlinguistic sounds in memory. We examined N400 amplitudes as adults viewed pictures presented with words or environmental sounds that matched the picture (Match), that shared semantic features with the expected match (Near Violation), and that shared relatively few semantic features with the expected match (Far Violation). Words demonstrated incremental N400 amplitudes based on featural similarity from 300–700ms, such that both Near and Far Violations exhibited significant N400 effects, however Far Violations exhibited greater N400 effects than Near Violations. For environmental sounds, Far Violations but not Near Violations elicited significant N400 effects, in both early (300–400ms) and late (500–700ms) time windows, though a graded pattern similar to that of words was seen in the mid-latency time window (400–500ms). These results indicate that the organization of words and environmental sounds in memory is differentially influenced by featural similarity, with a consistently fine-grained graded structure for words but not sounds.

The cross-modal double flash illusion depends on featural similarity between cross-modal inducers

Despite extensive evidence of the possible interactions between multisensory signals, it remains unclear at what level of sensory processing these interactions take place. When two identical auditory beeps (inducers) are presented in quick succession accompanied by a single visual flash, observers often report seeing two visual flashes, rather than the physical one — the double flash illusion. This compelling illusion has often been considered to reflect direct interactions between neural activations in different primary sensory cortices. Against this simple account, here we show that by simply changing the inducer signals between featurally distinct signals (e.g. high- and low-pitch beeps) the illusory double flash is abolished. This result suggests that a critical component underlying the illusion is perceptual grouping of the inducer signals, consistent with the notion that multisensory combination is preceded by determination of whether the relevant signals share a common source of origin.

R-metathesis in English: An account based on perception and frequency of use

The main properties of r-metathesis in English are its bi-directionality, variability and the attractive biases towards r created by some consonants but not by others. This article argues that a fully predictive and explanatory account of r-metathesis must consider evidence from two areas: phonetics and language use. On the perception side, the indeterminacy of the temporal organization of sequences involving r is an effective predictor of the instability of metathesis. The proposed analysis makes reference to extended phonetic cues and intrusive vowels that appear in the context of rhotics. The language-specific frequency of occurrence of phonotactic patterns is held responsible for the greater chance of some clusters to arise through metathesis than others. It is demonstrated that r-metathesis is best defined as a listener-initiated process rooted in perception. Abstract concepts like markedness have no obvious role to play as the process does not optimize syllable structure, nor does it improve on featural similarity.

Visual Crowding at a Distance during Predictive Remapping

When we move our eyes, images of objects are displaced on the retina, yet the visual world appears stable. Oculomotor activity just prior to an eye movement contributes to perceptual stability by providing information about the predicted location of a relevant object on the retina following a saccade. It remains unclear, however, whether an object's features are represented at the remapped location. Here, we exploited the phenomenon of visual crowding to show that presaccadic remapping preserves the elementary features of objects at their predicted postsaccadic locations. Observers executed an eye movement and identified a letter probe flashed just before the saccade. Flanking stimuli were flashed around the location that would be occupied by the probe immediately following the saccade. Despite being positioned in the opposite visual field to the probe, these flankers disrupted observers' ability to identify the probe. Crucially, this "remapped crowding" interference was stronger when the flankers were visually similar to the probe than when the flanker and probe stimuli were distinct. Our findings suggest that visual processing at remapped locations is featurally dependent, providing a mechanism for achieving perceptual continuity of objects across saccades.

Prereading Questions and Online Text Comprehension

Prereading questions can be an effective tool for directing students' learning. However, it is not always clear what the online effects of a set of prereading questions will be. In two experiments, this study investigated whether readers direct additional attention to and learn more from sentences that are potentially relevant to a set of prereading questions. Eye-tracking data indicated that participants directed additional attention (as indicated by first-pass reinspection and lookback duration) to sentences that were potentially relevant to the prereading questions they had received. Participants also learned more information from these sentences (as indicated by free recall rates). Judgment data suggested that the featural similarity (both lexical and semantic) of a sentence to a prereading question can be a strong indicator that a sentence will be deemed potentially relevant by readers. Results are discussed with respect to an account of instructional effects in which featural similarity drives early attentional allocation through memory-based processes.

Evidence of a transition from perceptual to category induction in 3- to 9-year-old children

We examined whether inductive reasoning development is better characterized by accounts assuming an early category bias versus an early perceptual bias. We trained 264 children aged 3 to 9years to categorize novel insects using a rule that directly pitted category membership against appearance. This was followed by an induction task with perceptual distractors at different levels of featural similarity. An additional 52 children were given the same training followed by an induction task with alternative stimuli. Categorization performance was consistently high; however, we found a gradual transition from a perceptual bias in our youngest children to a category bias around 6 or 7years of age. In addition, children of all ages were equally distracted by higher levels of featural similarity. The transition is unlikely to be due to an increased ability to inhibit perceptual distractors. Instead, we argue that the transition is driven by a fundamental change in children’s understanding of category membership.

Setting sights higher: category-level attentional set modulates sustained inattentional blindness

Previous research has shown that inattentional blindness is modulated by how people tune their "attentional set": the more featurally similar the unexpected object is to what people are trying to attend, the more likely it is that they will notice it. The experiments in this paper show that people can also establish attentional sets based on semantic categories, and that these high-level attentional sets modulate sustained inattentional blindness. In "Experiment 1", participants tracked four moving numbers and ignored four moving letters or vice versa, and the unexpected object was either a capital letter 'E' or its reverse, a block-like number '3'. Despite their featural similarity, participants were more likely to notice the unexpected object belonging to the same category as the tracked objects. "Experiment 2" replicated this effect in conditions where the unexpected object possessed a unique luminance and was less likely simply to be confused with other display items.

The influence of target discriminability on the time course of attentional selection

A wealth of neurophysiological data has demonstrated that visual attention can selectively enhance target representations early in the visual processing pathway. In conjunction, behavioural evidence tells us that the extent to which irrelevant items interfere with target processing depends on their featural similarity to the target. In this context, how does target discriminability influence temporal selection? We present results from an electrophysiology study that addresses this question by investigating the time course of the neural processes involved in target selection as target distinctiveness is varied. The results suggest that, in line with previous findings, making discrimination harder reduces the accuracy of target identification. We find that there are significant differences in the perceptual processing of the target in the two conditions, as indexed by early visual ERPs and the P3 ERP. We ground this and previous empirical evidence within a theoretical framework for understanding the mechanism of attentional selection represented in the ST2 model, a neural network model of temporal attention and working memory. By simulating both experimental conditions, we show that the model provides a convincing explanation of the pattern of experimental results, in addition to informing questions about the nature and time course of attentional selection.

Similarity, feature discovery, and the size principle

In this paper we consider the “size principle” for featural similarity, which states that rare features should be weighted more heavily than common features in people’s evaluations of the similarity between two entities. Specifically, it predicts that if a feature is possessed by n objects, the expected weight scales according to a 1 / n law. One justification of the size principle emerges from a Bayesian analysis of simple induction problems ( Tenenbaum & Griffiths, 2001), and is closely related to work by Shepard (1987) proposing universal laws for inductive generalization. In this article, we (1) show that the size principle can be more generally derived as an expression of a form of representational optimality, and (2) present analyses suggesting that across 11 different data sets in the domains of animals and artifacts, human judgments are in agreement with this law. A number of implications are discussed.

Finding similarity in a model of relational reasoning

Similarity plays a central role in the study of perception and cognition. Previous attempts to model similarity have captured effects of either featural or structural similarity, but typically not both. We simulated both by fitting similarity data with the LISA model of relational reasoning [Hummel, J. E., & Holyoak, K. J. (1997). Distributed representations of structure: A theory of analogical access and mapping. Psychological Review, 104, 427–466, Hummel, J. E., & Holyoak, K. J. (2003a). A symbolic-connectionist theory of relational inference and generalization. Psychological Review, 110, 220–264]. The same mechanisms LISA uses to simulate analogy also provide a natural account of feature-based similarity effects (e.g., violations of symmetry), structural effects (e.g., the advantage of alignable over non-alignable differences), and the combined effects of featural and structured information (i.e., MIPs and MOPs; “Matches In/Out of Place”) on similarity judgments. Our approach differs from most models of similarity in that LISA was not originally designed to simulate similarity judgments, but rather analogical reasoning. LISA’s incidental ability to simulate diverse similarity effects speaks to the plausibility of the model’s account of human knowledge representation.

Causal relations and feature similarity in children's inductive reasoning.

Four experiments examined the development of property induction on the basis of causal relations. In the first 2 studies, 5-year-olds, 8-year-olds, and adults were presented with triads in which a target instance was equally similar to 2 inductive bases but shared a causal antecedent feature with 1 of them. All 3 age groups used causal relations as a basis for property induction, although the proportion of causal inferences increased with age. Subsequent experiments pitted causal relations against featural similarity in induction. It was found that adults and 8-year-olds, but not 5-year-olds, preferred shared causal relations over strong featural similarity as a basis for induction. The implications for models of inductive reasoning and development are discussed.