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Do Illiterates Have Illusions? a Conceptual (Non)Replication of Luria (1976)

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Do Illiterates Have Illusions? a Conceptual (Non)Replication of Luria (1976) J Cult Cogn Sci (2021) 5:143–158 https://doi.org/10.1007/s41809-021-00080-x (0123456789().,-volV)( 0123456789().,-volV) RESEARCH PAPER Do illiterates have illusions? A conceptual (non)replication of Luria (1976) Mrudula Arunkumar . Jeroen van Paridon . Markus Ostarek . Falk Huettig Received: 17 February 2021 / Revised: 17 February 2021 / Accepted: 21 May 2021 / Published online: 1 June 2021 Ó The Author(s) 2021 Abstract Luria (Luria, Cognitive development: Its Keywords Culture Á Literacy Á Visual perception Á cultural and social foundations, Harvard University Visual illusions Press, 1976) famously observed that people who never learnt to read and write do not perceive visual illusions. We conducted a conceptual replication of the Luria study of the effect of literacy on the Introduction processing of visual illusions. We designed two carefully controlled experiments with 161 participants Psychology, the study of human behavior, is not with varying literacy levels ranging from complete immune to the influences of Zeitgeist and the domi- illiterates to high literates in Chennai, India. Accuracy nant political movements and ideologies of the time. and reaction time in the identification of visual shape The history of psychology in the 1920s and 30 s and color illusions and the identification of appropriate includes dark chapters such as the eugenic movement, control images were measured. Separate statistical which aimed to provide (pseudo)scientific explana- analyses of Experiments 1 and 2 as well as pooled tions for the claim that desirable qualities are hered- analyses of both experiments do not provide any itary traits to justify white supremacy and scientific support for the notion that literacy affects the percep- racism. The 1920s and 30 s also saw the rise of social tion of visual illusions. Our large sample, carefully utopian thinkers who advanced the idea of the social controlled study strongly suggests that literacy does origin of psychological processes and the mind. At the not meaningfully affect the identification of visual forefront of this movement were renowned Russian illusions and raises some questions about other reports psychologists Lev Vygotsky and Alexander Luria. of cultural effects on illusion perception. Strongly influenced by the ideas of Lev Trotsky, the Bolshevik revolution in 1917, and the founding of the Soviet Union, they embarked on a radical quest for a ‘new psychology’ towards the ‘socialist alteration’ for & M. Arunkumar ( ) Á J. van Paridon Á the ‘new man’ (Yasnitzky, 2019). M. Ostarek Á F. Huettig Max Planck Institute for Psycholinguistics, Nijmegen, the A main project of the Vygotsky-Luria ‘utopian Netherlands science of the superman of the communist future’ e-mail: [email protected] (Yasnitzky, 2019) was Luria’s large-scale investiga- tion of the effects of the rapid and forced ‘modern- F. Huettig Centre for Language Studies, Radboud University, ization’ and collectivization (i.e. adopting a Soviet Nijmegen, the Netherlands 123 144 J Cult Cogn Sci (2021) 5:143–158 model of cooperative agriculture) on cognition in research in Russia suggests that Luria’s description of illiterate peasants in Uzbekistan in 1931–1932. the illusions study is ‘‘not entirely quite accurate’’ Vygotsky and Luria believed that modernization in (Lamdan, 2013, p. 75). It has been suggested that he the Soviet Union, including changes in the education published the illusion results in 1976 only because system, would lead directly to a revolution in cogni- Koffka, the Gestalt psychologist who had been part of tive activity because all cognitive processes, they the illusions project, had very much disagreed with proposed, were socio-historical in nature (Luria, Luria’s interpretation (Allik, 2013). Yasnitzky (2019) 1976). The Soviet republic of Uzbekistan in Central has even argued that the Vygotsky-Luria research Asia provided Vygotsky and Luria with the perfect program in Uzbekistan ‘‘has for a long time been testing ground for these ideas. The vast majority of interpreted as one of the greatest success stories of the Uzbeks were completely illiterate (mostly villagers so- called ‘‘cultural-historical’’ psychology, but … it living in remote countryside) but enrolled in state was in fact probably the worst ever failure of Vygotsky literacy programs by the new rulers. and Luria’’ (p.15). This appears currently not to be Luria (1976) studied several areas with potential widely known outside of Russia, perhaps because of effects on perception and cognition including object the lasting influence of American psychologist Jerome naming, abstraction, syllogisms, and reasoning. Luria Bruner who heavily promoted and praised Vygotsky’s was most impressed, however, by the effects of work as ‘genius’ (e.g. Bruner, 1985; see the chapters in literacy on the perception of visual illusions, sending Yasnitzky, 2019, for a radical re-evaluation of a triumphant (but probably also, politically, tongue in Vygotsky’s research and legacy). cheek) ‘‘the Uzbekis have no illusions’’ telegraph In the present study, we had a fresh look at the effect message to Vygotsky (apparently intercepted by the of literacy on the processing of visual illusions. We KGB, who indeed took it as meaning Uzbekis were conducted two carefully designed and controlled disillusioned about Soviet rule, Nell, 1999). experiments with people with varying literacy levels Luria claimed ‘‘the number of illusions fluctuated (ranging from complete illiterates to high literates) in strongly, increasing to 75.6% as the educational level Chennai, India. We measured accuracy and reaction of the subjects rose… thus the data clearly show that time in the identification of two types of visual optical illusions are linked to complex psychological illusions (shape, color) and appropriate control processes that vary in accordance with socio-historical images. development… we can readily distinguish specific There are two reasons why it is important to geometrical structures that yield a high percentage of conduct another investigation of the relationship illusions among subjects with a higher educational between literacy and the perception of visual illusions level but that give rise to no such illusions among despite the unreliability of Luria’s (1976) findings. illiterate subjects’’ (p. 43, Luria, 1976.). Luria’s First, literacy is a relatively new human cultural account of the literacy research in Uzbekistan had an invention: the ability to read cannot have evolved enormous impact (his 1976 book has been cited more (Dehaene & Cohen, 2007; Huettig et al., 2018). The than 3500 times according to Google Scholar, Febru- first proper writing systems were invented between ary, 2021) and is still widely regarded as a seminal 5000 and 6000 years ago. On an evolutionary time finding in the study of cultural effects on perception scale, 5000–6000 years are only a tiny proportion of and cognition (e.g. ‘‘an important observation, which the existence of our species. Furthermore, until two to is now confirmed in many studies’’, p. 45, Kotik- three hundred years ago reading and writing was Friedgut, 2006). restricted to small groups of privileged individuals Russian scholars however have recently cast doubt (clergy or the wealthy who could afford education) but on Luria’s results (Allik, 2013; Goncharov, 2013; almost everybody else until very recently was illiter- Lamdan, 2013; Lamdan & Yasnitsky, 2016; Proctor, ate. This is far too short a time for evolution to have 2013; Yasnitzky, 2013). His 1976 description lacks created a genetically specified network in the brain methodological detail and rigor. Luria did not use that supports the task of reading. In other words, standardized tests but developed his own, which he effects of reading and writing on cognition are regarded as more meaningful than the tests developed cultural, and many such effects have been observed. and validated in other cultures. Recent historical Learning to read and write improves phonological 123 J Cult Cogn Sci (2021) 5:143–158 145 awareness (Morais et al., 1979), verbal memory time in the identification of visual shape (including all (Demoulin & Kolinsky, 2016; Smalle et al., 2019), the illusions that Luria tested such as the Mu¨ller-Lyer mirror image discrimination (Fernandes et al, 2021; illusion) and color illusions. We conducted two Kolinsky et al, 2011; Pegado et al., 2014), visual experiments. The second experiment was almost search (Olivers et al., 2014), face recognition (Van identical to the first but with minor changes in the Paridon et al., 2021), prediction in speech (Favier methodology that will be explained in detail in the et al., in press; Huettig & Pickering, 2019), and even method section of Experiment 2. Crucially, in both non-verbal intelligence as measured by Raven’s experiments we included appropriate control images progressive matrices (Hervais-Adelman et al., 2019; for each visual illusion. This allowed us to test whether Olivers et al., 2014; Skeide et al., 2017). any apparent literacy effect may ‘just’ be a literacy- Second, there are other reports in the literature related response bias rather than a literacy-related about effects of culture on the perception of visual difference in the visual perception of the illusion. illusions. Most well-known (and cited more than 1300 times, Google Scholar, February 2021) is Segall et al. (1966) finding that both children and adults from a Experiment 1 wide range of human societies show cultural differ- ences in the susceptibility to five different illusions
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