Week 10 - topic 3

Question 1

Pure alexia

Answer 1

• sometimes called pure word blindness, a loss of the ability to read without the loss of the ability to write
• Patients with pure alexia can recognize words that
are spelled out to them
• Therefore it is a perceptual disorder that is similar
to pure word deafness except that the patient has
trouble processing visual rather than audio
information.
• Caused by lesions that prevent visual information
getting to the visual association cortex of the left
hemisphere

Question 2

Reading

Answer 2

Reading involves two processes:

1. Direct recognition of the word as a whole.
2. Sounding out the word, letter by letter.

We use whole word reading (1) to process familiar words that we know.
We use phonetic reading (2) to process unfamiliar words that we don’t know (i.e. sounding words out)

Question 3

Acquired dyslexia

Answer 3

• Difficulties reading due to acquired brain damage:
1. Surface dyslexia - Deficit in whole word reading

2. Direct dyslexia – Deficit in understanding written
   words (not recognizing them)
3. Phonological dyslexia – deficit in sounding words
   out

Question 4

Surface dyslexia

Answer 4

• People with the disorder make errors related to
the visual appearance of words and to pronunciation rules – not to the “meaning” of words
• The individual can still “sound out” words, but will
make errors if the word doesn’t ‘sound’ how it is spelled
• Can read the word “hand” (regular spelling), but can’t read the word “pint” or “yacht” (irregular spelling).
• Can read nonwords (“glab”)
• Because the individual cannot recognize whole words, they have to listen to their own pronunciation (i.e. sounding out) to understand what they are reading

Question 5

Phonological dyslexia

Answer 5

• Opposite symptoms to surface dyslexia
• Individual can read using the whole-word process, but not the sounding out process.
• So, pronouncing familiar words is easy for these
individuals, but learning new words is more challenging

Question 6

Acquired dyslexia - what area of the brain is impacted

Answer 6

• Evidence suggests that the process of whole-word
reading involves the visual word form area (VWFA)
which is a region of the fusiform gyrus on the base of the temporal lobe.
• Exact location of phonological reading processes
somewhat uncertain – May involve a region that
surrounds the temporoparietal cortex and then follows a fibre bundle from this region to the inferior frontal cortex (including Broca’s area). The VWFA also appears to play a central role.

Question 7

Visual word form area

Answer 7

• Written words are visual. Therefore, there has to be
some part of the visual association cortex involved in
perceiving written words.
• VWFA found in the fusiform cortex of the left
hemisphere.

Question 8

Children and VWFA

Answer 8

• Reading words influences the development of neural
circuitry in the visual word form area
• Bren et al. (2010) – functional imaging study which
showed children who had not yet learned to read words
• At the beginning of the study, the words activated the
ventral occipitotemporal region in both hemispheres
• After 3-4 hours reading lessons (associate the words
with particular sounds) – the sight of the words activated only the left hemisphere

Question 9

Whole word reading and the VWFA

Answer 9

• Experienced readers take the same amount of time to read 3 letter and 6 letter words
• Whole word reading involves the VWFA – so this means that whole word reading doesn’t require processing of individual letters
• Damage to VWFA = surface dyslexia

Question 10

Dysgraphia

Answer 10

• Dysgraphia is a writing disturbance, common with dyslexia

* Various different types of writing disturbances.

Question 11

Writing and the brain

Answer 11

• Writing disorders can be related to spelling problems, or problems with making accurate movements of fingers, motor control etc.
• Many regions of the brain are involved in writing. For example, damage associated with different aphasias can result in similar writing impairments as those seen in speech.
• Organisation of the motor aspects of writing involves the dorsal parietal lobe and the premotor cortex. Damage to these regions results in dysgraphia

Question 12

Writing skills

Answer 12

• Like reading (which involves phonetic and whole word processing routes), writing involves more than one method.

Skills
• Audition
• Vision
• Memorization
• Motor memory

Question 13

Using audition in writing

Answer 13

• When children are learning a language, they first learn to recognize word sounds, then they learn to say the words, read them, and finally, write them
• Reading and writing depend on earlier learned skills
• To write a word, we must be able to “sound them out”

Question 14

Using vision in writing

Answer 14

• We might write by transcribing an image of what a
particular word looks like (copying a visual mental image)
• E.g. “looking off into the distance” to picture a word so you can remember how to spell it.
• This would involve visual memories

Question 15

Using memorization in writing

Answer 15

• Method of writing that involves memorizing letter
sequences
• We learn these sequences the same way we learn poems or musical lyrics
• E.g. saying the alphabet song you learn when you are a kid as an adult.
• It involves memorizing a sequences of letter names, not translating sounds into letters

Question 16

Using motor memory in writing

Answer 16

• We memorize motor sequences for typing or writing very familiar words such as our own names
• For example, there was a case of a man with brain
damage to ventral left front lobe that specifically impaired his ability to type (Otsuki et al.,, 2002)
• There has also been a case of someone who had specific deficits in motor memory for texting following a stroke of the junction between the left parietal and occipital lobes (Thomas and Mestre, 2017)

Question 17

Neural basis of writing - phonological dysgraphia

Answer 17

Neurological evidence provides strong evidence that we use audition, vision and memorization in writing

1. Phonological dysgraphia - a writing disorder in which
   the person cannot sound out words and write them
   phonetically.
   -> Appears to be caused by damage to regions of the
   brain involved in phonological processing and
   articulation (e.g. Broca’s area, ventral precentral gyrus and insula)

Question 18

Neural basis of writing - orthographic dysgraphia

Answer 18

Neurological evidence provides strong evidence that we use audition, vision and memorization in writing

2. Orthographic dysgraphia - a writing disorder in which
   the person can spell regularly spelled words but not
   irregularly spelled ones (i.e. a disorder of visually
   based writing)
   -> Appears to be caused by damage to the visual word
   form area

Question 19

Neural basis of writing - memory and writing

Answer 19

Neurological evidence provides strong evidence that we use audition, vision and memorisation in writing

3. Memory and Writing – patient who suffered a left
   hemisphere stroke that severely disrupted his ability to
   spell words orally and impaired his ability to recognize
   words that the examiners would spell aloud.
   -> Presumably, his ability to spell written words depended on the first two methods of writing: auditory and visual

Question 20

Reading and writing areas and functions

Answer 20

*look up image