The concept of homology as a basis for evaluating developmental mechanisms: Exploring selective attention across the life‐span

Abstract

Research with human infants as well as non-human animal embryos and infants has consistently demonstrated the benefits of intersensory redundancy for perceptual learning and memory for redundantly specified information during early development. Studies of infant affect discrimination, face discrimination, numerical discrimination, sequence detection, abstract rule learning, and word comprehension and segmentation have all shown that intersensory redundancy promotes earlier detection of these properties when compared to unimodal exposure to the same properties. Here we explore the idea that such intersensory facilitation is evident across the life-span and that this continuity is an example of a developmental behavioral homology. We present evidence that intersensory facilitation is most apparent during early phases of learning for a variety of tasks, regardless of developmental level, including domains that are novel or tasks that require discrimination of fine detail or speeded responses. Under these conditions, infants, children, and adults all show intersensory facilitation, suggesting a developmental homology. We discuss the challenge and propose strategies for establishing appropriate guidelines for identifying developmental behavioral homologies. We conclude that evaluating the extent to which continuities observed across development are homologous can contribute to a better understanding of the processes of development.

Intersensory redundancy hinders face discrimination in preschool children: Evidence for visual facilitation.

“…Thus far, tests of the IRH and demonstrations of unimodal and intersensory facilitation have focused primarily on infancy, the period when attention and perceptual processing skills are most limited. However, predictions of the IRH are proposed to extend across the life span, particularly when tasks are difficult in relation to the skills of the perceiver (Bahrick & Lickliter, 2002, 2012; Lickliter & Bahrick, 2013). For example, when learning new skills, or under conditions of high cognitive load or divided attention, children and adults are expected to show intersensory and unimodal facilitation similar to that of infants.…”