How Deep is Your Language?

Why are some languages easier to learn than others?

Reading is an essential skill, yet not all learners become proficient readers and many people struggle to develop literacy skills. Evidence indicates that some languages are easier to learn than others, the key thing being the depth of the orthography of that language. This refers to the spelling system of a language, the system by which the spoken language is recorded in written form.

What are ‘shallow’ and ‘opaque’ orthographies?

The orthography of a language is described as being ‘shallow’ or ‘transparent’ at one end of the scale, and ‘deep’ or ‘opaque’ at the other. The difference between the two is the extent to which letters consistently represent sounds. In other words, in a language with a  transparent orthography, written words are easier read because the letters always represent the same sound. Conversely, in a language with an opaque orthography, literacy can be harder to attain because letters don’t always represent the same sounds. 

Italian, Spanish and Ivrit (Hebrew) are examples of transparent languages. Letters consistently represent the same sounds and combinations of letters are pronounced the same, with some rare exceptions. Learners of transparent languages acquire literacy skills more easily and tend to experience fewer difficulties than learners of opaque languages. For example, research demonstrates that Italian learners are only half as likely to show signs of dyslexia than English learners. 

Why might this be? Well, one reason could be that English is opaque because there is a highly irregular and inconsistent relationship between letters and sounds. Some letters represent a number of different sounds, and single sounds can be represented by a number of different letters. It’s a complicated system to learn.  

What does an opaque language look like?

To illustrate what the opacity of English means in practice, read the following words, all of which follow the same spelling pattern, out loud: 

Tough      Through      Bough     

Cough    Thorough     Hiccough

See?

Seymour et al (2013) examined the acquisition of reading skills of children in 13 different European languages and found clear evidence to support the hypothesis that orthographic depth affects literacy learning. In other words, children learning opaque languages are more likely to experience difficulty learning to read than those learning transparent languages. Italian has 26 rules to learn, which takes about six months; English takes longer because there are many irregularities, and several hundred rules. 

Can someone be dyslexic in one language but not in another?

Wydell and Butterworth (1999) highlighted the case of Alan, whose parents were English, but he was born and grew up in Japan. He could pass as a native speaker of either language. What was particularly interesting about him was that he was severely dyslexic in one language, but in the top 10% of readers of his age. Which way round do you think? 

That’s right, while he was severely dyslexic in English, he excelled in Japanese. And research by US and Chinese scientists shows that it is possible for one person to be dyslexic in one language but not another. This is because different orthographies require us to use different parts of our brains to learn to read. Learning Chinese, a language in which each character maps onto a whole syllable, creates specific demands on the areas in the brain that remember visual patterns, while learning English, in which each sound (or phoneme) maps onto a single letter, uses the areas of the brain for phoneme processing. Different skills, different demands. 

Difficulty ‘segmenting’ syllables into separate sounds is a key issue in dyslexia and therefore dyslexia learners fare far worse learning English than they do in Chinese. 

Interestingly but not surprisingly given all of the above, the prevalence of dyslexia is reported to be much higher in English than in Chinese populations.  

Butterworth (1992) surveyed 8000 Chinese school children and found that approximately 1.5% were dyslexic. This suggests that although a difficulty blending and segmenting words into phonemes may be a sign of dyslexia in a reader in any language, it will be more pronounced and severe in a language which is reliant on phoneme processing, such as English. The trick for English learners is to apply a few different approaches to literacy acquisition, rather than rely on just one.