Michael Ramscar

The Roles of Body and Mind in Abstract Thought

How are people able to think about things they have never seen or touched? We demonstrate that abstract knowledge can be built analogically from more experience-based knowledge. Peoples understanding of the abstract domain of time, for example, is so intimately dependent on the more experience-based domain of space that when people make an air journey or wait in a lunch line, they also unwittingly (and dramatically) change their thinking about time. Further, our results suggest that it is not sensorimotor spatial experience per se that influences peoples thinking about time, but rather peoples representations of and thinking about their spatial experience.

Cognition Without Control When a Little Frontal Lobe Goes a Long Way

The prefrontal cortex is crucial for the ability to regulate thought and control behavior. The development of the human cerebral cortex is characterized by an extended period of maturation during which young children exhibit marked deficits in cognitive control. We contend that prolonged prefrontal immaturity is, on balance, advantageous and that the positive consequences of this developmental trajectory outweigh the negative. Particularly, we argue that cognitive control impedes convention learning and that delayed prefrontal maturation is a necessary adaptation for human learning of social and linguistic conventions. We conclude with a discussion of recent observations that are relevant to this claim of evolutionary trade-offs in a wide range of research areas, including attention-deficit hyperactivity disorder, autism spectrum disorders, creativity, and sleep.

On the Experiential Link Between Spatial and Temporal Language

How do we understand time and other entities we can neither touch nor see? One possibility is that we tap into our concrete, experiential knowledge, including our understanding of physical space and motion, to make sense of abstract domains such as time. To examine how pervasive an aspect of cognition this is, we investigated whether thought about a nonliteral type of motion called fictive motion (FM; as in The road runs along the coast) can influence thought about time. Our results suggest that FM uses the same structures evoked in understanding literal motion, and that these literal aspects of FM influence temporal reasoning.

The Effects of Feature‐Label‐Order and Their Implications for Symbolic Learning

Symbols enable people to organize and communicate about the world. However, the ways in which symbolic knowledge is learned and then represented in the mind are poorly understood. We present a formal analysis of symbolic learning-in particular, word learning-in terms of prediction and cue competition, and we consider two possible ways in which symbols might be learned: by learning to predict a label from the features of objects and events in the world, and by learning to predict features from a label. This analysis predicts significant differences in symbolic learning depending on the sequencing of objects and labels. We report a computational simulation and two human experiments that confirm these differences, revealing the existence of Feature-Label-Ordering effects in learning. Discrimination learning is facilitated when objects predict labels, but not when labels predict objects. Our results and analysis suggest that the semantic categories people use to understand and communicate about the world can only be learned if labels are predicted from objects. We discuss the implications of this for our understanding of the nature of language and symbolic thought, and in particular, for theories of reference.

The role of meaning in inflection: Why the past tense does not require a rule

How do we produce the past tenses of verbs? For the last 20 years this question has been the focal domain for conflicting theories of language, knowledge representation, and cognitive processing. On one side of the debate have been similarity-based or single-route approaches that propose that all past tenses are formed simply through phonological analogies to existing past tenses stored in memory. On the other side of the debate are rule-based or dual-route approaches which agree that phonological analogy is important for producing irregular past tenses (e.g., think-->thought), but argue that regular past tenses (e.g., walk-->walked) are generated via a +ed rule and that a principled account of regular inflection can only be given by recourse to explicit rules. This debate has become a crucial battleground for arguments concerning the necessity and importance of abstract mental rules, embracing not only language processing, but also the of nature cognition itself. However, in centering on the roles of phonological similarity and rules, the past tense debate has largely ignored the possible role of semantics in determining inflection. This paper presents five studies that demonstrate a striking and decisive role of semantic similarity in inflection. In fact, semantic factors appear to be more important in inflection than the grammatical considerations put forward by the dual-route account. Further, these new findings provide a new way of discriminating between the claims of single-route (similarity-based) and dual-route (rule-based) approaches. It appears that inflection is carried out through analogical reminding based on semantic and phonological similarity and that a rule-based route is not necessary to account for past tense inflection.

Developmental change and the nature of learning in childhood

How do children acquire humankinds remarkable cognitive skills? Why are the abilities children acquire readily, such as native-language fluency, harder for adults? Although attitudes to these questions span the continuum from nativism to learning theory, answers remain elusive. We relate a recent model of language acquisition in childhood to advances in the neuroscience of adult cognitive control, to propose a domain-general shift in the architecture of learning in childhood. The timing of this supports childrens imitative, unsupervised learning of social and linguistic conventions before the maturation of cognitive control gives individuals greater self-direction, which causes learning to become less conventionalized and more idiosyncratic. These changes might represent an important adaptation supporting the development and learning of cultural and linguistic conventions.

Linguistic Self-Correction in the Absence of Feedback: A New Approach to the Logical Problem of Language Acquisition

In a series of studies children show increasing mastery of irregular plural forms (such as mice) simply by producing erroneous over-regularized versions of them (such as mouses). We explain this phenomenon in terms of successive approximation in imitation: Children over-regularize early in acquisition because the representations of frequent, regular plural forms develop more quickly, such that at the earliest stages of production they interfere with childrens attempts to imitatively reproduce irregular forms they have heard in the input. As the strength of the representations that determine childrens productions settle asymptotically, the early advantage for the frequent regular forms is negated, and childrens attempts to imitate the irregular forms they have observed become more likely to succeed (a process that produces the classic U-shape in childrens acquisition of plural inflection). These data show that children can acquire correct linguistic behavior without feedback in a situation where, as a result of philosophical and linguistic analyses, it has often been argued that it is logically impossible for them to do so.

Relationships Between Language Structure and Language Learning: The Suffixing Preference and Grammatical Categorization

It is a reasonable assumption that universal properties of natural languages are not accidental. They occur either because they are underwritten by genetic code, because they assist in language processing or language learning, or due to some combination of the two. In this paper we investigate one such language universal: the suffixing preference across the worlds languages, whereby inflections tend to be added to the end of words. A corpus analysis of child-directed speech in English found that suffixes were more accurate at cuing the grammatical category of the root word than were prefixes. An artificial language experiment found that there was a learning advantage for suffixes over prefixes in terms of grammatical categorization within an artificial language. The results are consistent with an account of language universals that originate in general purpose learning mechanisms.

Sidestepping the Combinatorial Explosion: An Explanation of N-Gram Frequency Effects Based on Naive Discriminative Learning

Arnon and Snider ((2010). More than words: Frequency effects for multi-word phrases. Journal of Memory and Language, 62, 67–82) documented frequency effects for compositional four-grams independently of the frequencies of lower-order n-grams. They argue that comprehenders apparently store frequency information about multi-word units. We show that n-gram frequency effects can emerge in a parameter-free computational model driven by naive discriminative learning, trained on a sample of 300,000 four-word phrases from the British National Corpus. The discriminative learning model is a full decomposition model, associating orthographic input features straightforwardly with meanings. The model does not make use of separate representations for derived or inflected words, nor for compounds, nor for phrases. Nevertheless, frequency effects are correctly predicted for all these linguistic units. Naive discriminative learning provides the simplest and most economical explanation for frequency effects in language processing, obviating the need to posit counters in the head for, and the existence of, hundreds of millions of n-gram representations.

Children Value Informativity Over Logic in Word Learning

The question of how children learn the meanings of words has long puzzled philosophers and psychologists. As Quine famously pointed out, simply hearing a word in context reveals next to nothing about its meaning. How then do children learn to understand and use words correctly? Here, we show how learning theory can offer an elegant solution to this seemingly intractable puzzle in language acquisition. From it, we derived formal predictions about word learning in situations of Quinean ambiguity, and subsequently tested our predictions on toddlers, undergraduates, and developmental psychologists. The toddlers’ performance was consistent both with our predictions and with the workings of implicit mechanisms that can facilitate the learning of meaningful lexical systems. Adults adopted a markedly different and likely suboptimal strategy. These results suggest one explanation for why early word learning can appear baffling: Adult intuitions may be a poor source of insight into how children learn.