1. Models of Production and Comprehension [1] Ling4-437

2. Course outline and objectives  The course presents some of the basic models of language processing as well as some language production models  AIMS: To familiarize students with the METHODOLOGY used to investigate more and less subconscious processes of language perception and production

3. Aims (contd.)  To discuss (and reconcile) the claims made by opposing camps as to whether language is an autonomous system of cognition or a highly interactive one.

4. Emphasis on:  Visual and spoken word recognition  Sentence processing concentrating on the effects of CONTEXT on AMBIGUITY RESOLUTION.  Models of word production  Students are encouraged to design and carry out a small scale experiment in the LANGUAGE DEVELOPMENT LAB.

5. VISUAL WORD RECOGNITION  How a written word is recognized  Initial contact  Lexical selection  Word recognition

6. Old method  Tachistoscopic identification—  THRESHOLD for each item –  subliminal perception

7. Reaction time (RT) techniques  i. Naming task : naming latency is measured. ii. Lexical decision task: whether a string of letters is a word or not. Reaction times and error rates are measured. Problem: Speed-error trade-offs. iii. Semantic categorisation task: whether a word belongs to a specific semantic category (semantic field).

8. However  Absolute reaction time is not significant; only in relation to conditions.  Naming and lexical decision tasks tap different aspects of processing.

9. METHODS FOR TESTING WORD RECOGNITION  Brain scanning or imaging  Eye movements in reading.  Saccades and fixations.  More time looking at more unpredictable words: highly predictable ones can be altogether skipped.  Going back to avoid or restore mistakes involves regressive eye movements: these are important for finding out how we disambiguate ambiguous material.

10. PRIMING  It is easier to recognize a word when a semantically related word is presented just before it. SEMANTIC PRIMING. (doctor / nurse)  Priming is best reserved for methodology of investigating what happens when one word precedes another. Facilitation vs. Inhibition.  Stimulus-onset asynchrony (SOA) Prime- target: manipulating the relation between the prime and the target and by varying the SOA we learn a lot about visual word recognition.  A sentence or a whole picture could be the prime.

11. WHAT MAKES WORD RECOGNITION EASIER OR HARDER  Interfering with identification: we can make a word harder to recognize by degrading its physical appearance (stimulus degradation).  Breaking up the letters or reducing the contrast btw word and background or by rotating the word to an unusual angle.

12. WHAT MAKES WORD RECOGNITION EASIER OR HARDER (cond.)  Frequency of a word. Frequency counts are important: listing the occurrence per million of a large number of words (Kucera & Francis 1967 based on American English).  There are however differences between dialects (sidewalk vs. pavement) and btw written and spoken word frequency.  Familiarity is based on the idea that there is large variation on the basis of the experiential familiarity with low frequency words

13. WHAT MAKES WORD RECOGNITION EASIER OR HARDER (cond.)  Age at which you first learn a word (AOA): also with brain damaged patients, words with early AOA are easier to produce.  Cumulative frequency: how often the word is encountered throughout the lifespan.  AOA particularly affects word reading while cumulative frequency affects all tasks. !!! AOA as a result of loss of plasticity

14. LENGTH EFFECTS How can we measure word-length?  a. the time it takes to say it,  b. number of letters  c. number of syllables

15. NEIGHBORHOOD EFFECTS  some words have a large number of words that look like them. N-statistic: the number of words that can be created by changing one letter of the target word. N is a measure of neighborhood size (density). (e.g. mine vs. much)  Words with a high N are easy to recognize all else being equal. Clear benefits are only found though for low-frequency words: those with high N are faster to recognize, name and in lexical decision tasks than those with a low N.

16. WORD VS NON-WORD EFFECTS  words are responded to faster than non-words. Less plausible non-words are rejected faster than more plausible non-words.  Plausible non-words (i.e. ‘possible’ words) are called pseudowords.

17. REPETITION PRIMING  Once you identify a word, it is easier to identify it the next time you see it.  The technique of facilitating recognition of a word by repeating it, is called repetition priming.  Long-lasting effect (over several hours or even longer).  Repetition priming interacts with frequency. Results more obvious for low frequency words (frequency attenuation).

18. FORM-BASED (orelse Orthographic) PRIMING  ‘CONTRAST’ primes ‘CONTRACT’; orthographic priming. Very dubious effects (only with primes masked at short SOAs so that the prime is not consciously perceived).