Chapter 16: Chapter 16: In the Steps of the In the Steps of the ‘Diagram Makers’‘Diagram Makers’

Amy MenendezAmy Menendez

DefinitionsDefinitions AphasiaAphasia is the loss of a previously held ability is the loss of a previously held ability

to speak or understand spoken or written to speak or understand spoken or written language, due to disease or injury of the brain. language, due to disease or injury of the brain.

AlexiaAlexia is a neurological disorder marked by is a neurological disorder marked by loss of the ability to understand written or loss of the ability to understand written or printed language, usually resulting from a printed language, usually resulting from a brain lesion or a congenital defect. brain lesion or a congenital defect.

AgraphiaAgraphia is a cerebral disorder characterized is a cerebral disorder characterized by total or partial inability to write. by total or partial inability to write.

AnomiaAnomia is the inability to name objects or to is the inability to name objects or to recognize the written or spoken names of recognize the written or spoken names of objects. objects.

Broca’s AphasiaBroca’s Aphasia Broca’s aphasia is a Broca’s aphasia is a

type of aphasia type of aphasia caused by a lesion in caused by a lesion in Broca's area of the Broca's area of the brain. The brain. The predominant feature predominant feature is difficulty in is difficulty in finding and speaking finding and speaking words, yet patients words, yet patients have normal have normal comprehension.comprehension.Broca’s Area

Wernicke’s AphasiaWernicke’s Aphasia Wernicke’s aphasia is Wernicke’s aphasia is

a type of aphasia a type of aphasia caused by a lesion in caused by a lesion in Wernicke's area of Wernicke's area of the brain and the brain and characterized by characterized by grammatical but more grammatical but more or less meaningless or less meaningless speech and an speech and an apparent inability to apparent inability to comprehend speech. comprehend speech.

Wernicke’s Area

Conduction AphasiaConduction Aphasia Conduction Conduction

aphasia is a type of aphasia is a type of aphasia in which aphasia in which the lesion is the lesion is assumed to be in assumed to be in the association the association tracts connecting tracts connecting the various the various language centers language centers of the brain. of the brain.

Monsieur S.Monsieur S. Woke up one morning and could Woke up one morning and could

not read his newspaper.not read his newspaper. Could, however, recognize his Could, however, recognize his

own name, and could read figures.own name, and could read figures. Unable to write spontaneously or Unable to write spontaneously or

with dictation.with dictation. Comprehension of spoken Comprehension of spoken

language was normal, but when language was normal, but when he spoke he used wrong or he spoke he used wrong or malformed words. malformed words.

No difficulty recognizing people No difficulty recognizing people or objects.or objects.

Angular GyrusAngular Gyrus The angular gyrus is The angular gyrus is

a region of the a region of the inferior parietal lobe inferior parietal lobe of the brain that is of the brain that is involved in the involved in the processing of processing of auditory and visual auditory and visual input and in the input and in the comprehension of comprehension of language. language.

Jules DejerineJules Dejerine From studying Monsieur S. From studying Monsieur S.

Dejerine concluded damage Dejerine concluded damage to this area prevents the to this area prevents the conversion of conversion of representations of the representations of the appearance of words and appearance of words and letters into representations letters into representations of their sounds (of their sounds (alexiaalexia), and ), and also the conversion of also the conversion of representations of their representations of their sounds into representations sounds into representations of their appearance of their appearance ((agraphiaagraphia).).

Monsieur C.Monsieur C. Had alexia without Had alexia without

agraphia.agraphia. Although he could Although he could

write, he was unable write, he was unable to read what he had to read what he had written, unless he written, unless he could trace the letters could trace the letters with his fingers.with his fingers.

Unable to reproduce Unable to reproduce print as cursive or print as cursive or cursive as print.cursive as print.

Recognized patterns Recognized patterns without difficulty.without difficulty.

Dejerine’s Explanation of Dejerine’s Explanation of AlexiaAlexia

Because the left visual Because the left visual cortex had been destroyed cortex had been destroyed the letters and words could the letters and words could only have been seen only have been seen through signals reaching through signals reaching the right visual cortex.the right visual cortex.

For these letters and For these letters and words to be understood the words to be understood the right visual cortex would right visual cortex would have to be transferred to have to be transferred to areas of speech in the left areas of speech in the left hemisphere, but damage to hemisphere, but damage to the white matter in the the white matter in the hindermost part of the hindermost part of the corpus callosum made this corpus callosum made this impossible.impossible.

Dejerine’s Explanation of Dejerine’s Explanation of AgraphiaAgraphia

In the final attack on In the final attack on Monsieur C. The new Monsieur C. The new lesions destroyed the lesions destroyed the angular gyrus and angular gyrus and adjoining parts of both adjoining parts of both the temporal and the temporal and parietal lobes which parietal lobes which explained the explained the agraphia and agraphia and incomprehensible incomprehensible speech of Monsieur C.speech of Monsieur C.

Criticisms of the Diagram-Criticisms of the Diagram-making Approachmaking Approach

The localization of different functions were The localization of different functions were questioned. questioned.

Broca’s aphasia was simply the loss of ‘motor Broca’s aphasia was simply the loss of ‘motor images’ and Wernicke’s aphasia was a result images’ and Wernicke’s aphasia was a result of the loss of ‘auditory images’ failed to of the loss of ‘auditory images’ failed to account for the characteristic features of each.account for the characteristic features of each.

Although divided speech disorders into Although divided speech disorders into categories, and explained through models. The categories, and explained through models. The actual cases did not fit into the categories.actual cases did not fit into the categories.

Preoccupation with pinpointing damaged Preoccupation with pinpointing damaged centres or pathways and deducing the centres or pathways and deducing the consequences of the damage. (localization consequences of the damage. (localization approach)approach)

Cognitive Cognitive NeuropsychologistsNeuropsychologists

Cognitive Neuropsychology is a branch of Cognitive Neuropsychology is a branch of neuropsychology that aims to understand how neuropsychology that aims to understand how the structure and function of the brain relates the structure and function of the brain relates to specific psychological processes. It places a to specific psychological processes. It places a particular emphasis on studying the cognitive particular emphasis on studying the cognitive effects of brain injury or neurological illness effects of brain injury or neurological illness with a view to inferring models of normal with a view to inferring models of normal cognitive functioning. cognitive functioning.

““The most striking contribution of the cognitive The most striking contribution of the cognitive neuropsychologists has been to show that the neuropsychologists has been to show that the machinery handling language often behaves as machinery handling language often behaves as if it consists of interacting modules”.if it consists of interacting modules”.

Phonological and Lexical Phonological and Lexical Routes to ReadingRoutes to Reading

The phonological The phonological route to reading is route to reading is when we learn the when we learn the phonetics of phonetics of reading as well as reading as well as the rules of the rules of pronunciation.pronunciation.

The lexical route to reading The lexical route to reading is when we can read at a is when we can read at a glace without sounding out glace without sounding out letters or guidance from letters or guidance from rules. The spelling and rules. The spelling and pronunciation is already pronunciation is already stored in our brains.stored in our brains.

Hyena Yacht Colonel

Deep Alexia and Surface Deep Alexia and Surface AlexiaAlexia

When there is a block in the When there is a block in the phonological route, the patient is phonological route, the patient is said to be suffering from said to be suffering from phonological alexia or phonological alexia or deep alexiadeep alexia..

When there is a block in the lexical When there is a block in the lexical route the patient is said to be route the patient is said to be suffering from lexical alexia or suffering from lexical alexia or surface alexiasurface alexia..

Learning to Use WordsLearning to Use WordsSound

Patterns of Words

Meanings of Words

Appearances of Written

Words

Pathway A

Pathway C

Pathway B

Language DisordersLanguage Disorders She was able to read She was able to read

pronounceable non-words pronounceable non-words so her phonological so her phonological reading was intact. reading was intact. However, that couldn’t However, that couldn’t account for her being account for her being able to read words like able to read words like leopard, tortoise, and leopard, tortoise, and liquor.liquor.

Therefore, the lexical Therefore, the lexical route must include a route must include a pathway from the printed pathway from the printed word to the word sound word to the word sound that does not depend on that does not depend on comprehensioncomprehensionThis means pathway B, from sound patterns of words to appearances of written words, must exist!

Progressive Presenile Dementia

Language DisordersLanguage Disorders Had the ability to repeat and Had the ability to repeat and

write down spoken write down spoken sentences that she could not sentences that she could not understand, but could understand, but could understand what she had understand what she had written.written.

Inability to understand a Inability to understand a sentence after hearing it sentence after hearing it implies that pathway A, from implies that pathway A, from the sound of word to the the sound of word to the meaning of the word, was meaning of the word, was impaired.impaired.

Word-Meaning DeafnessThe fact that she could understand a sentence

after writing it down implies there is a route from the appearance of written words to the meaning of written words, so pathway C must exist!

Language DisordersLanguage Disorders When reading aloud, patients with Deep When reading aloud, patients with Deep

Alexia, tend to make semantic, word Alexia, tend to make semantic, word meaning, mistakes.meaning, mistakes.

These mistakes are significant because it These mistakes are significant because it not only shows a direct connection not only shows a direct connection between appearance of written words between appearance of written words and sound, pathway B, it also shows a and sound, pathway B, it also shows a direct connection between appearance of direct connection between appearance of written words and the meaning of written written words and the meaning of written words, pathway C.words, pathway C.

Right Brain vs. Left Right Brain vs. Left BrainBrain There is evidence to There is evidence to

support the right side of support the right side of the brain has to do with the brain has to do with object recognition, object recognition, spatial analysis, spatial analysis, recognition of musical recognition of musical pitch, timbre, and pitch, timbre, and harmony.harmony.

Emotional aspects of Emotional aspects of speech are controlled speech are controlled here.here.

The right half of the The right half of the brain is responsible for brain is responsible for controlling the left controlling the left hand, and the left visual hand, and the left visual field.field.

Gestures used to Gestures used to convey meaning are convey meaning are controlled in the left controlled in the left hemisphere.hemisphere.

Spoken language is Spoken language is on the left side of the on the left side of the brain. brain.

The left side of the The left side of the brain is also brain is also responsible for responsible for controlling the right controlling the right hand, and processing hand, and processing the right visual field.the right visual field.

Right Brain vs. Left Right Brain vs. Left BrainBrain

Look at the chart:Look at the chart:Say theSay the colorcolor not the word.not the word.

BlackBlack BlueBlue GreenGreenWhiteWhite GreenGreen RedRedGreenGreen AquaAqua YellowYellowYellowYellow PinkPink TanTanRedRed YellowYellow WhiteWhite

The Split BrainThe Split Brain Roger Sperry Roger Sperry

published a series published a series of papers in which of papers in which he described what he described what happened when he happened when he disconnected the disconnected the two hemispheres two hemispheres of the brain in of the brain in monkeys and cats.monkeys and cats.Optic Chiasma

Epilepsy and the Split Epilepsy and the Split BrainBrain

This procedure went from This procedure went from research in monkeys and research in monkeys and cats to research with cats to research with humans who had epilepsy.humans who had epilepsy.

The procedure was The procedure was performed, except the performed, except the optic chiasma was not optic chiasma was not cut.cut.

Not only did this prevent Not only did this prevent seizures from spreading seizures from spreading from one hemisphere to from one hemisphere to another it actually mad another it actually mad the seizures occur less the seizures occur less frequently. frequently.

Brain ScansBrain Scans PET scans allow us PET scans allow us

to measure changes to measure changes in local blood flow, in local blood flow, glucose consumption glucose consumption and and neurotransmitter neurotransmitter uptake.uptake.

MRI scans allow us MRI scans allow us to measure changes to measure changes in local blood flow in local blood flow and oxygen content. and oxygen content.

What Do These Scans Do What Do These Scans Do For Us?For Us?

These brain scans, These brain scans, specifically the specifically the PET scan, have PET scan, have shown us the parts shown us the parts of the brain of the brain associated with associated with auditory and visual auditory and visual stimuli.stimuli.

What Do These Scans Do What Do These Scans Do For Us?For Us?

They have shown us that They have shown us that our brains tend to store our brains tend to store information in a information in a phonological rather than phonological rather than visual form.visual form.

Findings indicate Findings indicate conditions that use the conditions that use the phonological store lead phonological store lead to an increase of blood to an increase of blood flow to the left flow to the left supramarginal gyrus.supramarginal gyrus.

Also indicate the sub-Also indicate the sub-vocal rehearsal system is vocal rehearsal system is associated with Broca’s associated with Broca’s area.area.

The supramarginal gyrus is involved with spatial orientation and semantic representation.

What Do These Scans Do What Do These Scans Do For Us?For Us?

These scans also These scans also provide us with provide us with insight to disorders insight to disorders such as dyslexia.such as dyslexia.

Once we have a full Once we have a full understanding of understanding of how these disorders how these disorders work, we can work to work, we can work to help people who help people who have them cope with have them cope with them better.them better.