A review of abstract concept learning in embodied agents and robots.

This paper reviews computational modelling approaches to the learning of abstract concepts and words in embodied agents such as humanoid robots. This will include a discussion of the learning of abstract words such as 'use' and 'make' in humanoid robot experiments, and the acquisition of numerical concepts via gesture and finger counting strategies. The current approaches share a strong emphasis on embodied cognition aspects for the grounding of abstract concepts, and a continuum, rather than dichotomy, view of concrete/abstract concepts differences.This article is part of the theme issue 'Varieties of abstract concepts: development, use and representation in the brain'

Moving beyond the distinction between concrete and abstract concepts

From the perspective of the situated conceptualization framework, the primary purpose of concepts is for categorizing and integrating elements of situations to support goal-directed action (including communication and social interaction). To the extent that important situational elements are categorized and integrated properly, effective goal-directed action follows. Over time, frequent patterns of co-occurring concepts within situations become established in memory as situated conceptualizations, conditioning the conceptual system and producing habitual patterns of conceptual processing. As a consequence, individual concepts are most basically represented within patterns of concepts that become entrained with specific kinds of physical situations. In this framework, the concrete versus abstract distinction between concepts is no longer useful, with two other distinctions becoming important instead: (i) external versus internal situational elements, (ii) situational elements versus situational integrations. Whereas concepts for situational elements originate in distributed neural networks that provide continual feeds about components of situations, concepts for situational integrations originate in association areas that establish temporal co-occurrence relations between situational elements, both external and internal. We propose that studying concepts in the context of situated action is necessary for establishing complete accounts of them, and that continuing to study concepts in isolation is likely to provide relatively incomplete and distorted accounts. This article is part of the theme issue ‘Varieties of abstract concepts: development, use and representation in the brain’

On staying grounded and avoiding Quixotic dead ends

The 15 articles in this special issue on The Representation of Concepts illustrate the rich variety of theoretical positions and supporting research that characterize the area. Although much agreement exists among contributors, much disagreement exists as well, especially about the roles of grounding and abstraction in conceptual processing. I first review theoretical approaches raised in these articles that I believe are Quixotic dead ends, namely, approaches that are principled and inspired but likely to fail. In the process, I review various theories of amodal symbols, their distortions of grounded theories, and fallacies in the evidence used to support them. Incorporating further contributions across articles, I then sketch a theoretical approach that I believe is likely to be successful, which includes grounding, abstraction, flexibility, explaining classic conceptual phenomena, and making contact with real-world situations. This account further proposes that (1) a key element of grounding is neural reuse, (2) abstraction takes the forms of multimodal compression, distilled abstraction, and distributed linguistic representation (but not amodal symbols), and (3) flexible context-dependent representations are a hallmark of conceptual processing

Learning Abstract Words and Concepts: Insights from Developmental Language Disorder

Some explanations of abstract word learning suggest that these words are learnt primarily from linguistic input, using statistical co-occurrences of words in language whereas concrete words can also rely on non-linguistic, experiential information. According to this hypothesis, we expect that, if the learner is not able to fully exploit the information in the linguistic input, abstract words should be affected more than concrete ones. Embodied approaches, instead, argue that both abstract and concrete words can rely on experiential information and, therefore, there might not be any linguistic primacy. Here, we test the role of linguistic input in the development of abstract knowledge with children with Developmental Language Disorder (DLD) and Typically Developing (TD) children aged 8-13. We show that DLD children, who by definition have impoverished language, do not show a disproportionate impairment for abstract words in lexical decision and definition tasks. These results indicate that linguistic information does not have a primary role in the learning of abstract concepts and words, rather, it would play a significant role in semantic development across all domains of knowledge

The Glasgow Norms:Ratings of 5,500 words on nine scales

The Glasgow Norms are a set of normative ratings for 5,553 English words on nine psycholinguistic dimensions: arousal, valence, dominance, concreteness, imageability, familiarity, age of acquisition, semantic size, and gender association. The Glasgow Norms are unique in several respects. First, the corpus itself is relatively large, while simultaneously providing norms across a substantial number of lexical dimensions. Second, for any given subset of words, the same participants provided ratings across all nine dimensions (33 participants/word, on average). Third, two novel dimensions—semantic size and gender association—are included. Finally, the corpus contains a set of 379 ambiguous words that are presented either alone (e.g., toast) or with information that selects an alternative sense (e.g., toast (bread), toast (speech)). The relationships between the dimensions of the Glasgow Norms were initially investigated by assessing their correlations. In addition, a principal component analysis revealed four main factors, accounting for 82% of the variance (Visualization, Emotion, Salience, and Exposure). The validity of the Glasgow Norms was established via comparisons of our ratings to 18 different sets of current psycholinguistic norms. The dimension of size was tested with megastudy data, confirming findings from past studies that have explicitly examined this variable. Alternative senses of ambiguous words (i.e., disambiguated forms), when discordant on a given dimension, seemingly led to appropriately distinct ratings. Informal comparisons between the ratings of ambiguous words and of their alternative senses showed different patterns that likely depended on several factors (the number of senses, their relative strengths, and the rating scales themselves). Overall, the Glasgow Norms provide a valuable resource—in particular, for researchers investigating the role of word recognition in language comprehension

Imageability ratings across languages

Imageability is a psycholinguistic variable that indicates how well a word gives rise to a mental image or sensory experience. Imageability ratings are used extensively in psycholinguistic, neuropsychological, and aphasiological studies. However, little formal knowledge exists about whether and how these ratings are associated between and within languages. Fifteen imageability databases were cross-correlated using nonparametric statistics. Some of these corresponded to unpublished data collected within a European research network-the Collaboration of Aphasia Trialists (COST IS1208). All but four of the correlations were significant. The average strength of the correlations (rho = .68) and the variance explained (R (2) = 46%) were moderate. This implies that factors other than imageability may explain 54% of the results. Imageability ratings often correlate across languages. Different possibly interacting factors may explain the moderate strength and variance explained in the correlations: (1) linguistic and cultural factors; (2) intrinsic differences between the databases; (3) range effects; (4) small numbers of words in each database, equivalent words, and participants; and (5) mean age of the participants. The results suggest that imageability ratings may be used cross-linguistically. However, further understanding of the factors explaining the variance in the correlations will be needed before research and practical recommendations can be made