Reading real words versus pseudowords: A meta-analysis of research in developmental dyslexia.

Abstract

Word reading is critical for reading development. However, it has long been debated on the processes involved in real word and pseudoword decoding in developmental dyslexia (DD). We conducted a meta-analysis of 28 neuroimaging studies (519 participants with DD, 562 typical readers, age range 5–63 years, female 37.65%, 382 foci, 64 experimental contrasts) using effect-size signed differential mapping. Individuals with DD compared with typical readers showed hypoactivity in the left-lateralized reading network, including the occipitotemporal regions, temporoparietal regions, and inferior frontal gyri (pars triangularis and pars opercularis), in real word and pseudoword decoding. In pseudoword compared with real word decoding, hypoactivity was more severely reduced in the inferior frontal gyrus (pars opercularis). Metaregression showed that no hypoactivity was associated with age in real word decoding, whereas in pseudoword decoding, hypoactivity in the left superior temporal gyrus was negatively associated with age and hypoactivity in the left inferior temporal gyrus was quadratically associated with age. Accommodating the connectionist triangle model, our findings demonstrate that DD may be associated with abnormalities in both the direct orthography–phonology and the indirect orthography–semantics–phonology pathways across real word and pseudoword decoding. Compared with real word decoding, pseudoword decoding in those with DD may be more associated with abnormalities in the indirect pathway. With development, abnormalities in both pathways seem stable in real word decoding. In pseudoword decoding, abnormalities in the indirect pathway become more severe initially but could be improved in later development; abnormalities in the direct pathway could be persistently becoming more severe with age.

The development of orthography and phonology coupling in the ventral occipito-temporal cortex and its relation to reading.

“…Also, our study tests developmental processes on real words (nouns) which have a strong semantic aspect as opposed to grammatical words or pseudowords. Because it was shown that lvOT processes are modulated by semantic factors (Wang et al, 2018) a different developmental pathway might be expected in the case of grammatical words or pseudowords (McNorgan & Booth, 2015; Zhang & Peng, 2022).…”

Dyslexia: Causes and Concomitant Impairments

“…The question of whether an impairment is a cause of DD or whether it is merely an accompanying deficit with no causal significance is also fundamental to the assessment of neural dysfunctions that may occur together with impaired abilities such as dyslexia [ 161 , 162 ]. Theories regarding the neural basis of DD mainly rely on functional magnetic resonance imaging (fMRI) studies [ 125 , 126 , 127 , 128 , 129 , 163 , 164 , 165 , 166 , 167 , 168 , 169 , 170 , 171 , 172 , 173 , 174 , 175 , 176 , 177 , 178 , 179 , 180 , 181 , 182 , 183 , 184 , 185 , 186 , 187 , 188 , 189 , 190 ]. An increase in the blood-oxygen-level-dependent (BOLD) signal in an area of the brain shows that this area is receiving sensory afferents or input from other brain areas [ 191 , 192 ].…”

Phonological and morphological literacy skills in English and Chinese: A cross‐linguistic neuroimaging comparison of Chinese–English bilingual and monolingual English children

“…Neurobiological theories of literacy development have largely been built on evidence from alphabetic languages (Ip et al, 2019; Yan et al, 2021). Much of this evidence comes from studies using phonological tasks that have linked phonology to literacy success and dyslexia (Maisog et al, 2008; Martin et al, 2016; Saygin et al, 2013; Zhang & Peng, 2022). At the core of these theoretical perspectives of the reading brain and resulting evidence is the functionality of the left superior temporal gyrus (STG) for recognizing word sounds in speech and print (Binder, 2017; Chyl et al, 2018).…”