Lecture6

Language – Understanding Words : Language – Understanding Words At the end of the lecture you will have learned that words are stored in the mental lexicon characteristics of words can influence the way we recognise them CORE READING: Parkin, A. (2000). Essential Cognitive Psychology. Ch 11 SUPPLEMENTARY: Gleitman, et al. (1999). Psychology; 5th Edition. Ch 9 Berko Gleason, et al. (2001). Psycholinguistics. Harcourt Brace, Ch 4 AIMS to examine how we store and process words Overheads http://129.215.50.40/Staff/ra/jsimner/teaching.html


Understanding words : Understanding words Average person has around 75,000 words in memory Takes only 250 msec (¼ sec) to find a word from among 75,000 Lexical Access retrieving a word from the mental lexicon accessing its lexical entry Mental Lexicon mental storehouse of words (in LTM) like a mental dictionary Lexical Entry the information about a word in the mental lexicon Spelling Pronunciation Meaning Syntactic category (noun, verb, etc.)


Random Organisation? : Random Organisation? cloth snooker marathon chair hillside telephone chop monkey horse cheese ballroom cake rain cliff floor slide bomb concert cleaner pullover television piano


The Organisation of the Lexicon : The Organisation of the Lexicon We can find out how words are organised by looking at things that make lexical access easy or hard How do we know whether a word is easy or hard to access? Lexical decision task


Lexical Decision Task : Lexical Decision Task Press YES or NO for whether the following is a real word in English: Non-words (BRUKE) are ‘fillers’ Just to check the subject is paying attention We only look at real words FAST response = easy to access SLOW response = hard to access HOUSE NOIK SLEEP NURSE BRUKE (450 msec) (500 msec)


What affects lexical access time? : 1. Word Frequency High frequency words = common words (cat, mother, house) Low frequency words = uncommon words (accordion, compass) What affects lexical access time? High frequency are faster to access than Low frequency even when they’re balanced on other features (e.g. length) E.g. Pen vs. Pun Rubenstein et al. (1970) What can this tell us about the organisation of the lexicon?


The Logogen Model Morton (1969) : The Logogen Model Morton (1969) Accounts for the frequency effect The lexical entry for each word comes with a logogen The lexical entry only becomes available once the logogen ‘fires’ When does a logogen fire? When you read/hear the word


Slide8 : Think of a logogen as being like a ‘strength-o-meter’ at a fairground When the bell rings, the logogen has ‘fired’


Slide9 : what makes the logogen fire? seeing/hearing the word what happens once the logogen has fired? access to lexical entry!


Slide10 : High frequency words have a lower threshold for firing E.g. cat vs. cot So how does this help us to explain the frequency effect? Low freq takes longer


Slide11 : Subject sees 2 words Must say YES or NO whether both are real words doctor grass doctor nurse … because nurse is already ‘warmed up’ by having just activated doctor 2. Semantic Priming Effects (Meyer andamp; Schvandeveldt, 1971) What affects lexical access time?


Slide12 : canary bird animal ostrich mammal Spreading Activation Model yellow doctor dentist fever green baby cradle bed hospital sun rain heat grass nurse delirium


Slide13 : canary bird animal ostrich mammal Spreading Activation Model yellow doctor dentist fever green baby cradle bed hospital sun rain heat grass nurse delirium


Fits nicely with Logogen Model : Fits nicely with Logogen Model Each of the nodes in the network has a logogen with it


Slide15 : canary bird animal ostrich mammal Semantic Network yellow doctor dentist fever green baby cradle bed hospital sun rain heat grass nurse delirium


Fits nicely with Logogen Model : Fits nicely with Logogen Model When we read doctor, its logogen fires doctor gets ‘activated’ Each of the nodes in the network has a logogen with it The activation from doctor spreads to nurse, this lowers the threshold for nurse so make nurse faster to access


Slide17 : spreading activation from doctor lowers the threshold for nurse to fire So nurse take less time to fire


Slide18 : like semantic priming, but for word related in sound (not meaning) trail chute shoot chute … because chute is already ‘warmed up’ by having just activated shoot 3. Phonological (sound) Priming (Evett andamp; Taylor, 1982) What affects lexical access time? What does this tell us about how the lexicon is organised? not only a semantic network but also an phonological network


Slide19 : canary bird animal ostrich mammal Semantic Network yellow doctor dentist fever green baby cradle bed hospital sun rain heat grass nurse delirium


Slide20 : poor pour shorn prawn pawn Phonological Network shin shoot chute shore sharp door dirt shirt short chin ship gin harp sure court


What affects lexical access time? : What affects lexical access time? 4. Unusual spelling (e.g. yacht) (Neighbourhood effects) Parkin et al. (1986) yacht peach … because peach has lots of spelling neighbours (e.g. reach, peace, beach, pea) Matched on frequency Having lots of neighbours means there’s constant activation in your neighbourhood this eventually starts to lower the firing threshold


Slide22 : reach Orthographic (=spelling) Networks teach pea read peach feature peat beach peace peal pace feast pest ache yacht yak This repeated activation starts to lower the threshold of peach so peach becomes easier to fire


Summary : Summary Each lexical entry in the mental lexicon comes with a logogen Words related by… meaning are linked in a semantic network sound are linked in a phonological network spelling are linked in an orthographic network Lexical access can be influenced by the following word characteristics: Word frequency Word meaning (if the word is related in meaning to one that has just been activated – Semantic priming) Word phonology (if the word sounds like a word that has just been activated – Phonological priming) Spelling regularity (neighbourhood effect)


Readings : Readings CORE READING: Parkin, A. (2000). Essential Cognitive Psychology. Psychology Press, Chap 11 SUPPLEMENTARY READING: Gleitman, et al. (1999). Psychology; 5th Edition. Norton. Chapter 9 Berko Gleason, J, et al. (2001). Psycholinguistics. Harcourt Brace, Chapter 4 Gernsbacher, M. A. (1994). Handbook of Psycholinguistics. Academic Press. Chapter 9