Exploring the Double Deficit Hypothesis and Working Memory ‎Span in Iranian EFL Learners: A Cognitive‑Psycholinguistic ‎Review

The Double Deficit Hypothesis (DDH) postulates that impairments in ‎phonological awareness and rapid automatized naming (RAN) constitute ‎two distinct and additive sources of reading difficulty. Although originally ‎conceptualized within the domain of developmental dyslexia in alphabetic ‎L۱ contexts, its theoretical relevance has increasingly extended to second‑‎language (L۲) reading environments. This review synthesizes international ‎literature on DDH and working memory (WM), and integrates emerging ‎empirical evidence from Iranian EFL learners. Iranian learners represent a ‎linguistically and educationally distinctive population characterized by ‎diglossic L۱–L۲ relations, orthographic depth differences, and high ‎cognitive demands in foreign‑language reading acquisition. Findings from ‎Iranian studies indicate that limitations in WM capacity and phonological ‎processing significantly predict L۲ reading comprehension, vocabulary ‎learning, and fluency performance. Additionally, research demonstrates ‎substantial overlap between deficits described by DDH and the cognitive ‎challenges documented among Iranian EFL students. This article critically ‎reviews theoretical frameworks, evaluates cross‑linguistic considerations, ‎and identifies contributions and gaps in the Iranian literature. Implications ‎are presented for cognitive‑informed assessment, targeted intervention, ‎and the refinement of EFL reading pedagogy within Iran. ‎

کلیدواژه ها:

Double Deficit Hypothesis ، Iranian EFL Learners ، Rapid Automatized Naming ، Reading ‎Deficiencies ، Working Memory ، ‎