Robin van Rijthoven

14 Chapter 1 Compensatory semantic abilities in children with dyslexia Results from neuroimaging studies have indicated that children with dyslexia, in contrast to typically developing children, show differences in brain activation during reading and spelling with underactivation in the posterior regions of the brain and relative overactivation in the anterior regions of the brain (Georgiewa et al, 2002; Hoeft et al., 2007; Shaywitz et al., 2005; Turkeltaub et al., 2003). The posterior regions are associated with the phonological deficit (Brunswick et al., 1999; Georgiewa et al., 1999). The anterior regions are known for various aspects of language processing (Bookheimer, 2002), making efficient processing of language possible (Bookheimer, 2002), such as encoding new memories, retrieval and selection of declarative and procedural knowledge (Buckner et al., 2001; Ullman, 2004), and memorization of verbal information (Smith & Jonides, 1999). Based on these findings, Kearns and colleagues (2019) and Hoeft et al. (2011) suggested that children with dyslexia may use different pathways to read compared to typically developing peers in an attempt to compensate for the dysfunctions in the posterior regions of the brain. This line of reasoning fits with the idea of Multifactorial causal models of dyslexia, in which both weaknesses and strengths together determine reading and spelling levels. It is also in line with the triangular framework, in which semantic representations are reciprocally connected to both phonological and orthographic representations (Seidenberg & McClelland, 1989). When the quality of semantic representations increases, phonological representations are pressured to improve as well according to the lexical restructuring hypothesis (Metsala & Walley, 1998). Indeed, prior behavioural research found a reciprocal connection between semantic and phonological representationsin the mental lexicon (Li et al., 2004). The development of these semantic representations may therefore give a boost to the development of phonological abilities (Duff et al., 2015; Haft et al., 2016; Hulme et al. 2010; Torppa et al.; 2010; Van Goch et al., 2014) and facilitate the process of learning to read (e.g., Van Bergen et al., 2014a) and spell (Ouellette, 2010; Tainturier & Rapp, 2001). Phonological and semantic skills may influence reading development from its earliest stages and influence each other as well (e.g., Laing & Hulme, 1999). In addition, Nation and Snowling (2004) and Ouellette and Beers (2010) showed that within the typically developing readers, semantic abilities beyond phonology make important contributions to word recognition development. Furthermore, Gijsel (2007) concluded that semantic orientated reading programs worked just as well as programs that focus on phonological training only. Prior research regarding reading indeed showed the benefits of well-developed semantic representations (e.g., Gijsel, 2007; Nation & Snowling, 2004; Torppa et al., 2010) and suggested semantic representations to play a role in spelling development as well (Ouellette, 2010; Ouellette & Fraser, 2009; Tainturier & Rapp, 2001).