Chapter 21 - Foundations of an Interactive Activation Model of Eye Movement Control in Reading

Abstract

Glenmore is an interactive-activation model of eye-movement control in reading. The model decouples the decision when to move the eyes from the word recognition process. The time course of activity in a “fixate centre” determines the triggering of a saccade. The other main feature of the model is the use of a saliency map that acts as an arena for the interplay of bottom-up visual features of the text and top-down lexical features. These factors combine to create a pattern of activation that selects one word as the saccade target. One of the goals of Glenmore is to explore the class of dynamical model, one that allows the interplay of factors from multiple levels of representation. The most appropriate class of modeling frameworks for this approach would be connectionist models and interactive activation models. The connectionist architecture of the Glenmore model is relatively simple, comprising input units, letter units, saliency units, and word units, as well as a “fixate centre” unit that controls the decision when to execute a new saccade. This decision is based on the general level of activity in the letter units; once activation in the fixate centre falls below a given threshold, a saccade is targeted to the most salient word ‘blob” on the saliency map.