Selective Inhibition of Mirror Invariance for Letters Consolidated by Sleep Doubles Reading Fluency

Author(s)

Torres, Ana Raquel ^[1] ; Mota, Natalia B. ^{[1, 2]} ; Adamy, Nery ^[1] ; Naschold, Angela ^[3] ; Lima, Thiago Z. ^[1] ; Copelli, Mauro ^[2] ; Weissheimer, Janaina ^{[1, 4]} ; Pegado, Felipe ^{[5, 6, 7]} ; Ribeiro, Sidarta ^[1]

Affiliation

^[1] Univ Fed Rio Grande do Norte, Brain Inst, Lab Memory Sleep & Dreams, Av Nascimento Castro 2155, BR-59056450 Natal, RN - Brazil

^[2] Univ Fed Pernambuco, Dept Phys, Av Jorn Anibal Fernandes S-N, BR-50740540 Recife, PE - Brazil

^[3] Univ Fed Rio Grande do Norte, Dept Educ, CERES, Rua Joaquim Gregorio 296, BR-59300000 Caico - Brazil

^[4] Univ Fed Rio Grande do Norte, Dept Modern Foreign Languages & Literatures, Av Sen Salgado Filho S-N, BR-59078970 Natal, RN - Brazil

^[5] CNRS, Lab Cognit Psychol, Inst Language Commun & Brain, 3 Pl Victor Hugo, F-13331 Marseille - France

^[6] Aix Marseille Univ, 3 Pl Victor Hugo, F-13331 Marseille - France

^[7] Katholieke Univ Leuven, Dept Brain & Cognit, Tiensestr 102, B-3000 Leuven - Belgium

• Document type: Journal article
• Source: Current Biology; v. 31, n. 4, p. 742+, FEB 22 2021.
• Web of Science Citations: 1

Abstract

Mirror invariance is a visual mechanism that enables a prompt recognition of mirror images. This visual capacity emerges early in human development, is useful to recognize objects, faces, and places from both left and right perspectives, and is also present in primates, pigeons, and cephalopods. Notwithstanding, the same visual mechanism has been suspected to be the source of a specific difficulty for a relatively recent human invention-reading-by creating confusion between mirror letters (e.g., b-d in the Latin alphabet). Using an ecologically valid school-based design, we show here that mirror invariance represents indeed a major leash for reading fluency acquisition in first graders. Our causal approach, which specifically targeted mirror invariance inhibition for letters, in a synergic combination with post-training sleep to increase learning consolidation, revealed unprecedented improvement in reading fluency, which became two-times faster. This gain was obtained with as little as 7.5 h of multisensory-motor training to distinguish mirror letters, such as ``b'' versus ``d.'' The magnitude, automaticity, and duration of this mirror discrimination learning were greatly enhanced by sleep, which keeps the gains perfectly intact even after 4 months. The results were consistently replicated in three randomized controlled trials. They not only reveal an extreme case of cognitive plasticity in humans (i.e., the inhibition in just 3 weeks of a similar to 25-million-year-old visual mechanism), that allows adaptation to a cultural activity (reading), but at the same time also show a simple and cost-effective way to unleash the reading fluency potential of millions of children worldwide. (AU)

• FAPESP's process: 13/07699-0 - Research, Innovation and Dissemination Center for Neuromathematics - NeuroMat
• Grantee: Oswaldo Baffa Filho
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC