W4: Words, word recognition and lexical decision tasks Flashcards
What are words?
Arbitrary symbols
There are a few exceptions: onomatopoeia that are designed to sound like the thing e.g. boom
What are lexical decision tasks?
Need to decide whether words are real words or not
Reaction time is measured in milliseconds
Reaction times in LDT are made up of what?
Lexical access (if the word is available in lexicon)
Decision making
Tapping computer key
What kind of trade-off is there in LDT and are there any gender differences?
Speed-accuracy trade off
Women are more likely to be accurate, men are more likely to be fast
What types of tasks are there in LDTs?
Semantic categorisation
Priming
What is semantic categorization?
Accessing what you know about an object - you need to think about its meaning and how it relates to other things
E.g. are the following objects bigger or smaller than a teacup
Priming in a LDT?
Presenting a priming stimulus before the target
When you see the word ‘nurse’ it becomes activates and this activation spreads to related words
Then, because of this activation recognition of other words such as doctor are quicker
What is stimulus-onset asynchrony (SOA)?
The time between the priming stimuli and the target stimuli
What factors affect word recognition (5)?
Physical interference
Frequency, familiarity and age of acquisition
Word length
Neighbouring effects (similar words)
Priming
How might physical interference affect word recognition?
Stimulus degradation
distortion
contrast reduction (background noise)
Backwards masking
presenting another stimulus immediately after target stimulus
How does frequency affect word recognition?
It’s about how often a word tends to appear in print/conversation
There are slight differences for written and spoken language (some things are said more than they are written)
Quicker and more accurate responses to high than to low-frequency words
However, frequency does not always equal…
Familiarity
How is frequency related to word length?
More common words tend to be shorter
How does age of acquisition affect word recognition?
Words learnt at an earlier age are responded to quickly
How does word length affect recognition?
Expect: longer response time for longer words
There is some word length effect, especially if the word is 5-12 letters long
Explain neighbourhood effects in word recognition
For low-frequency words specifically, words are responded to faster/more accurately if they have a large neighbourhood size (words similar but only vary in one sound or one letter)
Word status in word recognition?
People respond faster/more accurately to real words than to non-words
More plausible-looking non-words are responded to more slowly than less plausible looking nonwords (take time to realise they aren’t a word if they look like they may be whereas can respond quickly if they really do not look like a word)
How does repetition priming work?
It is easier to identify a word the second time you see it
What is form-based priming?
When a word is primed by a similar-looking word
Form - From
What is semantic priming?
Easier to identify a word if you’ve seen a word related in meaning
Bread – Butter
What are the 3 arguments as to how morphologically complex words are stored in the lexicon?
- Full listing
- Obligatory decomposition
- Dual-pathway
What is the full listing hypothesis?
Each word has a separate entry (lexeme) in the lexicon
Each variant has its own representations (glass, glasses, glassy, glasshouse)
What is the obligatory decomposition hypothesis?
Words are stored in root/base form and stripped of any affixes
Have a general rule and a list of exceptions
Eg. WALK and all of the bits that go with it ‘s’, ‘er’ and ‘ed’
Obliged to break words down into little bits
To produce them, you access individual morphemes and combine them to make a word
To comprehend: strip word of its affixes and activate the root word plus bound morphemes
What is the dual pathway hypothesis?
Most words are stored in their root form with rules for adding inflections and other affixes
However, some common derived/inflected forms have their own listing
Bit of both of the other two theories
What are the models of lexical access (3)?
Serial search (Forsters model)
Parallel access( Morton’s model & Modern interactionist models)
Explain serial search models of lexical access
You encounter a word
Then consult the lexicon - is it familiar?
Retrieve information on that word
Only one lexical entry scanned at a time
What is Forsters serial search model?
Each word is present in only one place in the lexicon BUT they can be accessed from various ‘access files’
These access files can be orthographic (visual), phonological (sound) and semantic/syntactic (meaning and grammar) - but can only use one at a time
Search to derive words location and partial info
THEN you need to search for words unique location and full information in the MASTER LEXICON
What is the master lexicon?
Organized into bins - access files direct search to the most appropriate bin
Entries are searched one by one until the exact match to the perceptual input is found
Most frequent entries are on the top
Explain Morton’s logogen model (parallel access model)
Words are accessed by being accessed to a certain threshold
Each word/morpheme has its own logogen - these logogens count the number of features that a lexical entry shares with the input
Info from the stimulus accrues in parallel - these logogens race to reach the activation threshold
Activation reaches one logogens pre-determined threshold and the word is recognized
- Logogen returns to resting level slowly
Word frequency in parallel access models?
Frequently used words have representations with lower thresholds so recognised quickly
Explain the connectionist model
Computer models of cognitive processing with nodes and connections between these nodes
Organisation: strength of the connection between nodes, based on past association. If they are strong they are likely to excite and activate others
Explain how words change in rapid speech and a study that relates to this
The speed of connected speech is fast, words are not clearly articulated yet we understand
- sometimes we need context to understand
- word boundaries are lost in fluent speech
Pollack and Pickett
- Spliced individual words from fluent speech and replayed to participants in isolation.
Listeners found them unrecognisable
How long do pauses during speech last? and how often do they occur?
200-250 ms
Occur every 5-8 words, occupying 40-50% of speaking time
If the planning demands on the speaker are reduced, do pauses decrease?
If reading aloud from a script, pauses are reduced but still occupy 20% of speech
Suggests that pauses are necessary outside of planning
Pauses may be unfilled (e.g. silence), but also filled. What can be used to fill a pause?
Repetition
False starts
Parenthetical remark ‘you know…, like..’
What are the two kinds of planning that may constitute pauses?
Macroplanning
Microplanning
What is microplanning?
May have difficulty retrieving individual word - this is more common before low-frequency words
(tip-of-the-tongue phenomenon)
What is macroplanning?
Difficulty determining syntax and context
Seems to determine more pauses than microplanning difficulties
What is prosody?
The acoustic cues accompanying the spoken sentence including:
Intonation (changes in pitch)
Word stress (emphasising different words)
Pauses (help to understand sentences)
Vowel lengthening
Are we taught prosody?
No, no one teaches us this. We just pick it up
What can prosody help with?
Sentence processing
Signals whether the speaker is happy, sad, angry, sarcastic
Disambiguates meaning
What is parsing and why is it important?
Parsing is the assignment of words in a sentence to their linguistic categories (noun, verb, adjectives)
Vital for COMPREHENSION: What makes an alcoholic (noun vs. adjective) drink (verb vs. noun)
And PRODUCTION: the present (adjective vs. noun) studies (noun vs. verb) results
We need to know what the words are in order to understand
