Neural correlates of visual statistical learning and morphological processing

Investigator: Joanna Morris, Providence College
Mentor: James Morgan, Brown University

Theme: Neuroscience
Title: Neural correlates of visual statistical learning and morphological processing 
Award: Early Career Development (2022-2024)

Abstract: Dyslexia is a brain-based learning disorder that involves difficulty reading despite adequate sensory and perceptual ability, intelligence, and opportunities to learn. Recently, several research groups have shown that individual differences in the capacity for statistical learning are linked with variability in word reading accuracy. However, we still do not have a clear understanding of the mechanisms that give rise to these associations. One possibility is that deficits in statistical learning lead to an insensitivity to internal word structure and hence to word reading difficulty. My goal is to examine the extent to which individual differences in implicit statistical learning impact word recognition. The innovative nature of this research program lies in the fact that it brings together work in individual differences, morphological processing, statistical learning—the ability for humans and other animals to extract statistical regularities from the world around them—and cognitive electrophysiology to increase our understanding of the possible neural bases of dyslexia and other reading difficulties. I would like to specify the role that domain-general mechanisms of implicit learning play in acquisition of morphology and how individual differences in sensitivity to statistical patterns, as reflected in patterns of brain activity, affect this learning. I plan to do this by measuring the (a) quality of readers’ lexical representation, (b) their sensitivity to the internal structure of words and (c) their ability to pick up on statistical patterns in visual sequences. I will correlate these behavioral measures with electrophysiological of brain activity to identify neural signatures of implicit statistical learning and determine if similar neural mechanisms are employed in complex word recognition. We expect our research program to have a positive impact because strong, precise lexical representations are the key to skilled reading and writing performance. Attention to the statistical structure of language input plays an important role in developing these representations. Therefore, it is important to understand how these differences are reflected in brain structure and function and how they correlate with the ability to acquire and use morphological representations across individuals. Answers to these questions present unexplored opportunities to focus remediation efforts for individuals diagnosed with reading difficulties. Finally, in addition to expanding our knowledge base in the neural bases of dyslexia more generally and in the role of statistical learning more specifically, funding the research described in this proposal will also allow my laboratory and our department here at Providence College to continue to train and to prepare talented undergraduate students for successful careers in the neurosciences.

Relevance: Dyslexia is a brain-based learning disorder that involves difficulty in recognizing words. One possibility is that people with dyslexia experience difficulty in learning about the internal structure of words. We will measure brain activity to determine if there are differences between good and poor readers in the ability to pick up on the internal structure of a word. By identifying such differences, we hope to better understand the process of word recognition and therefore to design more effective ways of helping children learn to read.