Word recognition

Question 1

What is needed first in order to be able to recognise words?

Answer 1

Alphanumeric recognition (ability to recognise letters)

Question 2

What is template matching? Is it bottom-up or top-down processing?

Answer 2

The stimulus is matched to a template in long-term memory - bottom-up.

Question 3

What is feature analysis?

Answer 3

Features are analysed through cortical cell ‘filters’ which measure size, orientation, shape etc and matched to known templates.

Question 4

What is the pandemonium model by Selfridge (1959)?

Answer 4

There are four stages in cortical processing - split into ‘demons’.
1: Image demons detect the stimulus
2: Feature demons respond to an element of the stimulus (orientation, colour etc)
3: Cognitive demons react to the input and match the shapes by comparing templates and choosing which is most similar
4: Decision demon makes the final decision using input from cognitive demons

Question 5

Which areas of the visual pathway relate to each stage of the pandemonium model?

Answer 5

Image = retina
Feature = V1
Cognitive = V2/IT
Decision = ?

Question 6

What is structural modelling and why does it result in easier recognition?

Answer 6

Description of an object (e.g. describing how a letter looks), becomes easier bc px is able to imagine the shape

Question 7

What is the word superiority effect?

Answer 7

Letters are identified faster if they are in a familiar word or combination, possibly due to language rules/ redundant letters

Question 8

What are the reasons for the word superiority effect?

Answer 8

Pronounceability differences
Frequency
Meaningfulness
Orthographic regularity
Neighbourhood density

Question 9

What are pronounceability differences?

Answer 9

Non-words are harder to remember bc they aren’t recognised and don’t form memorable rounds

Question 10

What is frequency?

Answer 10

Real words are seen more often so are more easily remembered

Question 11

What is meaningfulness?

Answer 11

Real words have semantic meaning so are more easily remembered

Question 12

What is orthographic regularity?

Answer 12

Real words follow spelling conventions so are more easily recognised/remembered

Question 13

What is neighbourhood density?

Answer 13

Real words are normally similar to others

Question 14

Where is the Visual Word Form Area (VWFA) and what does it do?

Answer 14

Left fusiform gyrus
Perceives words

Question 15

Are words processed top-down or bottom-up?

Answer 15

Top-down

Question 16

What helps us to process words quickly?

Answer 16

Familiar letter, word and sentence combinations - allows for prediction so we don’t have to work as hard to understand it.

Question 17

Why can we still understand misspelt words?

Answer 17

We make guesses based on context around the words/letters so sometimes misspellings are missed bc we’re not actually reading every single letter/word

Question 18

What is the missing letter effect?

Answer 18

We skip over function words like ‘the’ and ‘and’ - they are processed quickly to help us understand sentence structure

Question 19

Does word spacing affect how easy it is to read sentences?

Answer 19

Yes - but easier to understand a sentence with no spacing than a combination of random words with no spacing

Question 20

What is alexia?

Answer 20

Complete inability to read words as a whole due to brain damage - may have to read one letter at a time. Might also struggle with number and face recognition

Question 21

What is bilateral projection?
How is a centrally fixated word processed?

Answer 21

There is a 2-3 degree overlap of the hemifields at the fovea
This means that a centrally fixated word is processed by both brain hemispheres, no crossing at the corpus callosum required (so processing is faster)

Question 22

What’s the evidence for bilateral projection?

Answer 22

Macular sparing - suggests healthy RGCs from one side still able to process vision when the other side is damaged
RGCs present on both sides of midline in monkeys

Question 23

What is the split fovea?
How is a centrally fixated word processed?

Answer 23

There is no overlap in the fovea, it’s split centrally
A centrally fixated word is processed half and half by each side of the brain and must be combined via the corpus callosum

Question 24

What’s the evidence for split fovea?

Answer 24

Macular sparing isn’t present in all hemianopias
Px’s with bisected corpus callosum find words easier to read if they are fixated to one side or the other (so one side of fovea/brain is processing it)