Universal Sketch Perceptual Grouping

In this work we aim to develop a universal sketch grouper. That is, a grouper that can be applied to sketches of any category in any domain to group constituent strokes/segments into semantically meaningful object parts. The first obstacle to this goal is the lack of large-scale datasets with grouping annotation. To overcome this, we contribute the largest sketch perceptual grouping (SPG) dataset to date, consisting of 20, 000 unique sketches evenly distributed over 25 object categories. Furthermore, we propose a novel deep universal perceptual grouping model. The model is learned with both generative and discriminative losses. The generative losses improve the generalisation ability of the model to unseen object categories and datasets. The discriminative losses include a local grouping loss and a novel global grouping loss to enforce global grouping consistency. We show that the proposed model significantly outperforms the state-of-the-art groupers. Further, we show that our grouper is useful for a number of sketch analysis tasks including sketch synthesis and fine-grained sketch-based image retrieval (FG-SBIR). © Springer Nature Switzerland AG 2018

Infants’ sensitivity to nonadjacent vowel dependencies: The case of vowel harmony in Hungarian

Vowel harmony is a linguistic phenomenon whereby vowels within a word share one or several of their phonological features, constituting a nonadjacent, and thus challenging, dependency to learn. It can be found in a large number of agglutinating languages, such as Hungarian and Turkish, and it may apply both at the lexical level (i.e., within word stems) and at the morphological level (i.e., between stems and their affixes). Thus, it might affect both lexical and morphological development in infants whose native language has vowel harmony. The current study asked at what age infants learning an irregular harmonic language, Hungarian, become sensitive to vowel harmony within word stems. In a head-turn preference study, 13-month-old, but not 10-month-old, Hungarian-learning infants preferred listening to nonharmonic VCV (vowel–consonant–vowel) pseudowords over vowel-harmonic ones. A control experiment with 13-month-olds exposed to French, a nonharmonic language, showed no listening preference for either of the sequences, suggesting that this finding cannot be explained by a universal preference for nonharmonic sequences but rather reflects language-specific knowledge emerging between 10 and 13 months of age. We discuss the implications of this finding for morphological and lexical learning

The relationship between language production and verbal short-term memory: The role of stress grouping

This study investigates the influence of stress grouping on verbal short-term memory (STM). English speakers show a preference to combine syllables into trochaic groups, both lexically and in continuous speech. In two serial recall experiments, auditory lists of nonsense syllables were presented with either trochaic (STRONG-weak) or iambic (weak-STRONG) stress patterns, or in monotone. The acoustic correlates that carry stress were also manipulated in order to examine the relationship between input and output processes during recall. In Experiment 1, stressed and unstressed syllables differed in intensity and pitch but were matched for spoken duration. Significantly more syllables were recalled in the trochaic stress pattern condition than in the iambic and monotone conditions, which did not differ. In Experiment 2, spoken duration and pitch were manipulated but intensity was held constant. No effects of stress grouping were observed, suggesting that intensity is a critical acoustic factor for trochaic grouping. Acoustic analyses demonstrated that speech output was not identical to the auditory input, but that participants generated correct stress patterns by manipulating acoustic correlates in the same way in both experiments. These data challenge the idea of a language-independent STM store and support the notion of separable phonological input and output processes

Language and culture in perception: a three-pronged investigation of phylogenetic, ontogenetic and cross-cultural evidence

Brown and Lenneberg (I954) and Rosch Heider (1972) were among the first to conduct psychological investigations to test the Whorfian view that language affects thought. They both asked about colour categories. The debate has continued with some research supporting a relativist (Whorfian) account (Davidoff, Davies & Roberson, I999; Borodistsky, 200I), and some supporting a universalist account (e.g., Kay & Regier, 2003; Spelke & Kinzler, 2007). The present thesis adds to the debate by taking three different approaches i.e., cross-cultural, ontogenetic and phylogenetic frames in which to carry out investigations of categorization of various perceptual continua. Categorical Perception's hallmark is the effect of mental warping of space such as has been found for phonemes (Pisani & Tash, I974) and colour (Bornstein & Monroe, I980; Bornstein & Korda, I984). With respect to colours, those that cross a category boundary seem more distant than two otherwise equally spaced colours from the same category. Warping is tested using cognitive methods such as two-alternative-forced-choice and matching-to-sample. Evidence is considered for the continua under investigation i.e. colour and animal patterns. Experiments 1 and 2 find evidence of categorical perception for human-primates and not for monkeys. Experiment 3 finds that Himba and English human adults categorize differently, particularly for colours crossing a category boundary, but also show broad similarity in solving the same matching-to-sample task as used with the monkeys (experiment I) who showed clear differences with humans. Experiment 4 and 5 tested Himba and English toddlers and found categorical perception of colour mainly for toddlers that knew their colour terms despite prior findings (Franklin et al., 2005) indicative of universal colour categories. In experiment 6, Himba and English categorical perception of animal patterns was tested for the first time, and result indicate a cross-category advantage for participants who knew the animal pattern terms. Therefore, a weak Whorfian view of linguistic relativity's role in obtaining categorical perception effects is presented. Although there is some evidence of an inherent human way of grouping drawn from results of experiment 1 and 3, results in all experiments (1,2,3,4,5, and 6) show that linguistic labels and categorical perception effects go hand-in-hand; categorization effects are not found when linguistic terms are not acquired at test and have not had a chance to affect cognition. This was true for all populations under observation in this set of studies, providing further support for effects of language and culture in perception