Non-adjacent Dependency Learning in Humans and Other Animals.

Benjamin Wilson,Kenny Smith,Anne Van Der Kant,Jutta L Mueller,Michelle Spierings,Toben H Mintz,Frank Wijnen,Andrea Ravignani,Arnaud Rey

doi:10.1111/tops.12381

Abstract

Learning and processing natural language requires the ability to track syntactic relationships between words and phrases in a sentence, which are often separated by intervening material. These nonadjacent dependencies can be studied using artificial grammar learning paradigms and structured sequence processing tasks. These approaches have been used to demonstrate that human adults, infants and some nonhuman animals are able to detect and learn dependencies between nonadjacent elements within a sequence. However, learning nonadjacent dependencies appears to be more cognitively demanding than detecting dependencies between adjacent elements, and only occurs in certain circumstances. In this review, we discuss different types of nonadjacent dependencies in language and in artificial grammar learning experiments, and how these differences might impact learning. We summarize different types of perceptual cues that facilitate learning, by highlighting the relationship between dependent elements bringing them closer together either physically, attentionally, or perceptually. Finally, we review artificial grammar learning experiments in human adults, infants, and nonhuman animals, and discuss how similarities and differences observed across these groups can provide insights into how language is learned across development and how these language‐related abilities might have evolved.

Highlights

A central feature of syntactic processing is the ability to track structural relationships between words and phrases in a sentence
We summarizse the evidence for nonadjacent dependency learning in human adults and infants, and nonhuman animals, review the conditions under which learning does and does not occur, and discuss the insights these studies provide into the development and evolution of these abilities
We review how human adults and infants and nonhuman animals have been tested using these paradigms to better understand how different types of dependencies (Figs. 1 and 2) are learned and how these might vary across development and evolution

Summary

Introduction

A central feature of syntactic processing is the ability to track structural relationships between words and phrases in a sentence. Such tasks do not rely on existing semantic or syntactic knowledge and are an important tool with which to isolate and study the cognitive and neurobiological systems that support how specific aspects of syntax may be learned and processed (Petersson, Folia, & Hagoort, 2012) These tasks seem to tap into language-relevant capacities, as evidenced by correlations between nonadjacent dependency learning and natural language processing in adult humans (Misyak, Christiansen, & Tomblin, 2010), and by the fact that nonadjacent dependency learning is impaired in individuals with specific language impairment (Hsu, Tomblin, & Christiansen, 2014) or familial risk of dyslexia (Kerkhoff, De Bree, De Klerk, & Wijnen, 2013). We summarizse the evidence for nonadjacent dependency learning in human adults and infants, and nonhuman animals, review the conditions under which learning does and does not occur, and discuss the insights these studies provide into the development and evolution of these abilities

Characterizing different types of nonadjacent dependency

Human adults and infants

Incremental increases in complexity

Nonhuman animals

Conclusions