Researchers discover how spelling errors slow down reading in Russian

Psycholinguists from the Centre for Language and Brain at HSE University–St Petersburg have shown that words that are frequently misspelled are processed more slowly by readers, even when presented with the correct spelling. The researchers confirmed this effect for the first time using Russian-language materials and found that response speed is most strongly linked to how confidently individuals can distinguish the correct spelling of a word from an incorrect one. The study has been published in The Mental Lexicon.

People are constantly exposed to misspelled words—in social media, chats, and comments. A spelling error may seem trivial—just an alternative way of writing a word, but it can still affect the reader. A few years ago, researchers showed that in English, the recognition of frequently misspelled words is slowed even when these words are spelled correctly. The effect was later confirmed for Chinese, Finnish, Greek, and Hebrew but found to vary across languages. In languages with opaque orthographies, such as English and Chinese, high-frequency words were more strongly affected, whereas in languages with transparent orthographies, such as Greek and Finnish, the effect was more pronounced for low-frequency words. Psycholinguists from the Centre for Language and Brain at HSE University–St Petersburg, in collaboration with colleagues from St Petersburg State University and the University of Nova Gorica (Slovenia), set out to examine whether this pattern holds for Russian. They also compared standard word recognition with intentional spelling error detection to determine whether words are processed in the same way in these two tasks.

First, using a corpus of social media texts, including posts, comments, and messages, the researchers selected 62 words that are frequently misspelled in Russian, and then conducted four online experiments with independent groups of participants, involving a total of 269 native speakers of Russian. In two experiments, participants were presented with real and nonce words and asked to determine as quickly as possible whether each word exists in Russian. 

In the other two groups, participants were asked to decide whether a word was spelled correctly or misspelled. Based on the results, the researchers assessed both reaction time and response accuracy. This design allowed them to compare word processing in tasks without a focus on spelling and in those that explicitly required the detection of spelling errors. 

The study showed that frequently misspelled words are indeed processed more slowly. The authors attribute this to spelling uncertainty: when correct and incorrect variants of a word compete in a person’s memory, the brain takes longer to recognise the correct form. When a word is stored in memory, its spelling, sound, and meaning are encoded together. If a person is frequently exposed to misspelled versions, these forms are also retained. As a result, the correct spelling competes with incorrect variants, slowing down recognition.

It was important to assess not only how often a word occurs in its incorrect form, but also how well participants can distinguish the correct spelling from the incorrect one. This factor showed the strongest correlation with reaction time. In contrast, word frequency and the number of possible erroneous variants had a weaker effect. 

'If a word is frequently misspelled and the reader is uncertain about its correct spelling, it becomes more difficult to process—even when written correctly. Moreover, the effect was stronger for low-frequency words, meaning that in this respect Russian behaves not like English or Chinese, but more like Finnish and Greek. This was somewhat unexpected, since Russian orthography is considered less transparent: one must pay attention to unstressed vowels, voiced and voiceless consonants, and many other features, whereas in Finnish and Greek words are largely spelled as they are pronounced,' explains Natalia Slioussar, Leading Research Fellow at the Centre for Language and Brain at HSE University–St Petersburg and co-author of the study.

In the error detection tasks, participants were more successful at identifying some spelling errors than others, partly depending on the type of spelling pattern. Words with an extra or missing double consonant were particularly challenging. By contrast, participants more easily recognised errors in words whose spelling can be verified by changing the word’s form. However, this effect emerged only when participants were consciously searching for spelling errors.

The results of the study are important not only for understanding how word processing works, but also for more practical applications, such as the design of spelling tests.

'We deliberately selected words that vary in complexity and are not too easy for most participants, in order to identify those more confident in recognising correct spellings. Such a set can be used as material for spelling tests,' explains study co-author Daria Chernova, Senior Research Fellow at the Institute of Cognitive Studies at St Petersburg State University. 

'Spelling memory is shaped by what we read every day. If we are exposed to many texts with misspelled words, they become part of our language experience alongside correct spellings. Therefore, it is worth reading high-quality books and articles more often,' comments Natalia Slioussar.

The study was conducted with support from HSE University's Basic Research Programme within the framework of the Centres of Excellence project.