Why It’s Harder for Adults to Learn to Read

Despite a steady rise in literacy rates over the past 50 years, there are still an estimated 773 million adults worldwide who cannot read or write in any language (UNESCO 2022).  While policymakers and academics have primarily focused on educating children, and for good reason, adult learning and education (ALE) programs are an important component of addressing the literacy gap.  Yet 42 percent of countries spent less than one percent of their public education budgets on such programs, and adult literacy programs are often characterized by low attendance, high dropout, limited skills attainment, and rapid skills depreciation.

Why is literacy learning in adulthood so difficult?  In a new working paper, we examine both theory and empirics to better understand just that, and how programs can address it.

Overall, the paper points out three key learnings, set out below.

1. Adults face barriers to learning, including higher opportunity costs and lower brain plasticity

Unsurprisingly, adults face unique barriers to learning, compared with children. As we get older, things can get…well, more difficult. Studies from the fields of cognitive psychology and educational neuroscience show that attaining the foundational skills of literacy can be challenging, not only due to the complexity of the task—which involves multiple areas of the brain—but also lower levels of “brain plasticity”. This becomes even more difficult if the language is “opaque” (a limited correspondence between letters and their sounds), or when learning new scripts—recent research posits that adults become dyslexic for new alphabets at about the age of 19 (Abadzi 2019). This, combined with socio-economic factors—the high opportunity costs of adults’ time, difficult learning environments, uncertain returns with education—can make adult literacy challenging.

2. Adult education programs rarely address these constraints, which limits their impacts on sustained learning

Empirical research on adult education programs suggests that the results are mixed. In general, existing evidence suggest that adult education programs are more successful in boosting math skills, rather than reading skills, and when reading gains do occur, adults do not achieve fluency and hence these gains cannot be easily sustained (Alamprese et al 2011, Sabatini et al 2011, Aker et al 2012, Banerji et al 2017, Abadzi et al 2010, Aker et al 2012, 2019, 2020). This is potentially due to a number of reasons-the failure of adult education curricula to position literacy as relevant to daily life, with corresponding impacts on learning, motivation and time for practice; the timing of literacy programs around the agricultural calendar, with important implications for the curriculum and insufficient time for adults to practice; the time commitment (which is significant) as compared to adults’ busy lives; and the neurocognitive obstacles to adult learning, which impede learning, and further decrease motivation.

3. Adult education programs are most successful when social, economic, and neurocognitive factors are incorporated

All of this suggests that adult education programs have the potential to be more successful when they address the key barriers to learning in adulthood. This not only means that the material should be properly sequenced, but also that students can read fast enough in order to understand what they are reading. This requires that students are given sufficient (and flexible) time to practice, perhaps via the provision of perceptually enhanced texts (e.g., large text size and spacing with many pages for practice (Abadzi 2019).  At the same time, this need for sufficient practice must be balanced with the opportunity costs for adult learners—either by having programs at certain times of day or year, or allowing it to be done remotely. And learning and time must be done in conjunction with addressing learners’ intrinsic and extrinsic motivation, in part by making such skills relevant to daily life, allowing for practice outside of the classroom, allowing students to experience “quick wins” or providing scholarships (or other support). Research using simple mobile phones as a pedagogical device in Niger and the US have suggested that potentially simple technologies may overcome some of these constraints—by allowing students to learn more flexibly, use their skills daily and practice outside of the classroom (Aker et al 2012, Ksoll et al 2018). 

For more, read the working paper.


CGD blog posts reflect the views of the authors, drawing on prior research and experience in their areas of expertise. CGD is a nonpartisan, independent organization and does not take institutional positions.