Global and Local Feature Distinctiveness Effects in Language Acquisition

Various aspects of semantic features drive early vocabulary development, but less is known about how the global and local structure of the overall semantic feature space influences language acquisition. A feature network of English words was constructed from a large database of adult feature production norms such that edges in the network represented feature distances between words (i.e., Manhattan distances of probability distributions of features elicited for each pair of words). A word's global feature distinctiveness is measured with respect to all other words in the network and a word's local feature distinctiveness is measured relative to words in sub-networks derived from clustering analyses. This paper investigates how feature distinctiveness of individual words at local and global scales of the network influences language acquisition. Regression analyses indicate that global feature distinctiveness was associated with earlier age of acquisition ratings, and was a stronger predictor of age of acquisition than local feature distinctiveness. These results suggest that the global structure of the semantic feature network could play an important role in language acquisition, whereby globally distinctive concepts help to structure vocabulary development over the lifespan.     

Anxiety and depression: toward overlapping and distinctive features

ABSTRACT

This Special Issue of Cognition and Emotion addresses one of the cardinal concerns of affective science, which is overlapping and distinctive features of anxiety and depression. A central finding in the study of anxiety and depression is that they are moderately highly correlated with each other. This leads us to the question: What is behind this co-occurrence? Possible explanations relate to poor discriminant validity of measures; both emotional states are associated with negative affect; stressful life events; impaired cognitive processes; they share a common biological/genetic diathesis. However, despite a set of common (nonspecific) features, anxiety and depression are clearly not identical emotional states. Differences between them might be best viewed, for example, through their heterogeneous and multi-layered nature, adaptive functions and relations with regulatory processes, positive affect, and motivation or complex cognitive processes. In this introduction we consider several approaches (e.g. functional approach; tripartite model and content-specificity hypothesis) to which most research in this Special Issue is relevant. In addition, we have asked contributors to this Special Issue to indicate how their own studies on comparisons between anxiety and depression and models on anxiety and depression move this area of research to more mature science with applicability.     

Influence of cryomilling on the microstructural features in HVOF-sprayed NiCrAlY bond coats for thermal barrier coatings: Creation of a homogeneous distribution of nanoscale dispersoids

Previous research has revealed that thermal barrier coatings with cryomilled bond coats exhibit improved thermal cycling lifetime by growing a continuous and uniform oxide layer at a slower rate; yet the mechanism controlling the ultimate failure remains unclear. In an effort to provide a foundation for understanding the improved behavior, the influence of cryomilling on the microstructure of the NiCrAlY bond coat material is investigated in this article. Rather than focusing on the alumina scale formation, the microstructural features and their evolution within the high-velocity oxy-fuel (HVOF)-sprayed NiCrAlY bond coats themselves, prepared from conventional powder and cryomilled powder, were carefully compared through extensive scanning electron microscope/energy-dispersive X-ray spectroscopy characterization. In addition, the as-cryomilled NiCrAlY powder is characterized to provide evidence of the direct influence of cryomilling and to exclude the impact from the HVOF spraying. It is found that the essential change in microstructural features resulting from the cryomilling is the creation of a homogeneous distribution of ultrafine (nanoscale) Al-rich oxide/nitride dispersoids, which remain thermally stable even after exposure at 1100°C for 100 h. The TEM study on the as-cryomilled powder, prior to the HVOF spraying, indicates that some Al and Y-rich oxides are already present within the material as a direct result of the cryomilling process.     

Facial expression discrimination varies with presentation time but not with fixation on features: A backward masking study using eye-tracking

The current study investigated the effects of presentation time and fixation to expression-specific diagnostic features on emotion discrimination performance, in a backward masking task. While no differences were found when stimuli were presented for 16.67 ms, differences between facial emotions emerged beyond the happy-superiority effect at presentation times as early as 50 ms. Happy expressions were best discriminated, followed by neutral and disgusted, then surprised, and finally fearful expressions presented for 50 and 100 ms. While performance was not improved by the use of expression-specific diagnostic facial features, performance increased with presentation time for all emotions. Results support the idea of an integration of facial features (holistic processing) varying as a function of emotion and presentation time.     

A functional near-infrared spectroscopy study of sustained attention to local and global target features

Despite a long history of vigilance research, the role of global and local feature discrimination in vigilance tasks has been relatively neglected. In this experiment participants performed a sustained attention task requiring either global or local shape stimuli discrimination. Reaction time to local feature discriminations was characterized by a quadratic trend over time-on-task with performance levels returning to initial levels late in the task. This trend did not occur in the global shape discrimination task. Functional near-infrared spectroscopy (fNIRS) was utilized in this study as an index of cerebral activation. In both tasks there was increased right hemisphere relative to left hemisphere oxygenation and right hemisphere oxygenation increased with time-on-task. Left hemisphere oxygenation, however, decreased slightly in the global task, but increased significantly in the local task as task duration increased. Indeed, total oxygenation, averaging both right and left, increased more with time-on-task in the local discrimination task. Both the performance and physiological results of this study indicate increased utilization of bilateral cerebral resources with time-on-task in the local, but not the global discrimination vigil.     

Verbal cues flexibly transform spatial representations in human memory

ABSTRACT

Humans possess a unique ability to communicate spatially-relevant information, yet the intersection between language and navigation remains largely unexplored. One possibility is that verbal cues accentuate heuristics useful for coding spatial layouts, yet this idea remains largely untested. We test the idea that verbal cues flexibly accentuate the coding of heuristics to remember spatial layouts via spatial boundaries or landmarks. The alternative hypothesis instead conceives of encoding during navigation as a step-wise process involving binding lower-level features, and thus subsequently formed spatial representations should not be modified by verbal cues. Across three experiments, we found that verbal cues significantly affected pointing error patterns at axes that were aligned with the verbally cued heuristic, suggesting that verbal cues influenced the heuristics employed to remember object positions. Further analyses suggested evidence for a hybrid model, in which boundaries were encoded more obligatorily than landmarks, but both were accessed flexibly with verbal instruction. These findings could not be accounted for by a tendency to spend more time facing the instructed component during navigation, ruling out an attentional-encoding mechanism. Our findings argue that verbal cues influence the heuristics employed to code environments, suggesting a mechanism for how humans use language to communicate navigationally-relevant information.     

Source misattributions and false recognition errors: Examining the role of perceptual resemblance and imagery generation processes

In three experiments, we examine the extent to which participants’ memory errors are affected by the perceptual features of an encoding series and imagery generation processes. Perceptual features were examined by manipulating the features associated with individual items as well as the relationships among items. An encoding instruction manipulation was included to examine the effects of explicit requests to generate images. In all three experiments, participants falsely claimed to have seen pictures of items presented as words, committing picture misattribution errors. These misattribution errors were exaggerated when the perceptual resemblance between pictures and images was relatively high (Experiment 1) and when explicit requests to generate images were omitted from encoding instructions (Experiments 1 and 2). When perceptual cues made the thematic relationships among items salient, the level and pattern of misattribution errors were also affected (Experiments 2 and 3). Results address alternative views about the nature of internal representations resulting in misattribution errors and refute the idea that these errors reflect only participants’ general impressions or beliefs about what was seen.     

Discrimination of familiar human faces in dogs (Canis familiaris)

Faces are an important visual category for many taxa, and the human face is no exception to this. Because faces differ in subtle ways and possess many idiosyncratic features, they provide a rich source of perceptual cues. A fair amount of those cues are learned through social interactions and are used for future identification of individual humans. These effects of individual experience can be studied particularly well in hetero-specific face perception. Domestic dogs represent a perfect model in this respect, due to their proved ability to extract important information from the human face in socio-communicative interactions. There is also suggestive evidence that dogs can identify their owner or other familiar human individuals by using visual information from the face. However, most studies have used only dogs’ looking behavior to examine their visual processing of human faces and it has been demonstrated only that dogs can differentiate between familiar and unknown human faces. Here, we examined the dog's ability to discriminate the faces of two familiar persons by active choice (approach and touch). Furthermore, in successive stages of the experiment we investigated how well dogs discriminate humans in different representations by systematically reducing the informational richness and the quality of the stimuli. We found a huge inter-individual and inter-stage variance in performance, indicating differences across dogs in their learning ability as well as their selection of discriminative cues. On a group level, the performance of dogs significantly decreased when they were presented with pictures of human heads after having learned to discriminate the real heads, and when – after relearning – confronted with the same pictures showing only the inner parts of the heads. However, as two dogs quickly mastered all stages, we conclude that dogs are in principle able to discriminate people on the basis of visual information from their faces and by making active choices.     

Investigation of the process underpinning vowel‐size correspondence

Vowel‐size correspondence is frequently reported in the literature: Namely, the vowels a and i tend to elicit bigger and smaller images, respectively. Previous studies have speculated that two factors may contribute to this vowel‐size correspondence: the acoustical features of vowels and the speaker's kinesthetic experience of producing them. However, these two factors have been investigated without being considered separately in previous research. In this study, we investigated the process underpinning vowel‐size correspondence by using speeded classification tasks and manipulating the two factors mentioned above separately in two experiments. The results of Experiment 1 indicate that a and i elicited bigger and smaller images even in the absence of kinesthetic experience. The results of Experiment 2 indicate that the proprioception of the size of the oral cavity on its own may not contribute to vowel‐size correspondence. Thus, the acoustic features of vowels mainly contribute to vowel‐size correspondence, although other possibilities are also discussed.     

Listeners learn phonotactic patterns conditioned on suprasegmental cues

Language learners are sensitive to phonotactic patterns from an early age, and can acquire both simple and 2nd-order positional restrictions contingent on segment identity (e.g., /f/ is an onset with /æ/but a coda with /?/). The present study explored the learning of phonototactic patterns conditioned on a suprasegmental cue: lexical stress. Adults first heard non-words in which trochaic and iambic items had different consonant restrictions. In Experiment 1, participants trained with phonotactic patterns involving natural classes of consonants later falsely recognized novel items that were consistent with the training patterns (legal items), demonstrating that they had learned the stress-conditioned phonotactic patterns. However, this was only true for iambic items. In Experiment 2, participants completed a forced-choice test between novel legal and novel illegal items and were again successful only for the iambic items. Experiment 3 demonstrated learning for trochaic items when they were presented alone. Finally, in Experiment 4, in which the training phase was lengthened, participants successfully learned both sets of phonotactic patterns. These experiments provide evidence that learners consider more global phonological properties in the computation of phonotactic patterns, and that learners can acquire multiple sets of patterns simultaneously, even contradictory ones.