Reading for reading aloud

Models of reading aloud – Dual-route & Parallel-distribution processing approaches (Coltheart, 1993)

• Argued that various facts about skilled reading aloud cannot be explained by any model unless that model possesses a dual-route architecture (lexical nonlexical routes from print to speech)

• Fundamental property of dual-route models of reading is the idea that skilled readers have at their disposal two different procedures for converting print to speech

  1. A dictionary lookup procedure

  2. Letter to sound rule procedure

• Lexical route of reading aloud

  1. Any word the reader has learned is represented as an entry in a mental dictionary or internal lexicon

  2. words can be read aloud by accessing the word’s lexical entry from its printed form & retrieving from that entry the word’s pronunciation

  3. will succeed when the input string is a word but will deliver no output when it is a non-word

• Nonlexical route of reading aloud

  1. Readers read aloud pronounceable letter string that they have never seen before

  2. Non-words do not possess lexical entries

  3. Allows the correct reading aloud of pronounceable nonwords & of words that obey the spelling-sound rules of English

     • Will deliver incorrect translations of the exception or irregular words of English words

  4. Will deliver correct output when input string is a non or a regular word

  5. Will deliver an incorrect output (regularisation error) when input string is an exception word

• Glushko (1979) & Marcel (1980)

  1. Argued that nonwords are read aloud by some form of analogy process

  2. Involves a nonword activating the lexical entities for words that are orthographically similar to it

  3. Nonword reading is not nonlexical & is not based on explicit tules

• Dual-route model

  1. Provides a strong explanation for reading aloud particularly in cases of brain damage affecting reading ability

  2. Suggests reading aloud operates via 2 distinct pathways

     • Lexical route (whole word processing)

       • Direct word recognition

       • used for familiar

       • used for both regular and irregular words as long as they are known

       • words are recognised from a mental lexicon (bypassing phoneme-to-grapheme conversion)

     • Nonlexical route (phonological conversion)

       • Grapheme-to-phoneme conversion

         • Converts letters in sounds

           • Explains why we can read new words aloud even if we've never seen them before

       • used for unfamiliar words

       • used for novel/non-words

     • accounts for differences between regular, irregular & non words in reading performance

• Evaluation of the dual route model

  1. More comprehensive explanation for reading aloud  

  2. Acknowledges further refinements in both models are necessary to fully understand the reading process

  3. Surface dyslexia

     • P w/damage to the lexical route struggle to read non-words but can read familiar words correctly

     • These patterns support existence of 2 distinct processing routes

  4. Alternative models struggle to accounr for double dissociations seen in acquired dyslexia

     • Parallel Distributed processing model (PDP)

       • Based on the connectionist principle, using networks of simple processing units

       • Learning occurs through statistical patterns in training data rather than separate processing units

Modelling reading: the dual route approach (Coltheart, 2005)

• The idea of two reading pathways dates back to de Saussure (1922).

• Became widely recognised in the 1970s (e.g., Forster & Chambers, 1973; Marshall & Newcombe, 1973).

• Evolved into explicit box-and-arrow models (e.g., Baron, 1977).