1. Study of the neural bases of language development and use
Language and the Brain
Study of the neural bases of language development and use

2. Neuro and Psycholinguistics
Neurolinguistics: the study of the neural and electrochemical bases of language development and use.
Psycholinguistics: the study of the acquisition, storage, comprehension and production of language.

3. The Brain: Children vs. Adults
Child’s brain trauma and brain Plasticity
Adult’s brain trauma and irreversible damage
C.f. Critical Period Hypothesis (CPH)

4. The Brain: Basics The Hemispheres Left Hemisphere Right Hemisphere
Connected by corpus collosum –a bundle of 200 million nerve fibers

5. The Brain: Basics 1/4” thick layer covering the brain
Makes human capable of higher cognitive functions
Gyri (bumps)
Fissures (depressions)
The Cortex

6. The Brain: Basics White matter – nerve cell fibers
Reflex actions – breathing, heartbeat, etc.
Sub-cortex

7. The Brain: Basics Frontal Lobe Parietal Lobe Temporal Lobe
The Lobes
Frontal Lobe
Parietal Lobe
Temporal Lobe
Occipital Lobe

8. The Brain: Basics Frontal Lobe
Concerned with reasoning, planning, parts of speech and movement (motor cortex), emotions, and problem-solving.

9. Dr. Walter Freeman, the Lobotomist
Beulah Jones:
Howard Dully:

10. The Brain: Basics Parietal Lobe
Concerned with perception of stimuli related to touch, pressure, temperature and pain.

11. The Brain: Basics Temporal Lobe
Concerned with perception and recognition of auditory stimuli (hearing) and memory (hippocampus).

12. The Brain: Basics Occipital Lobe
Concerned with many aspects of vision.

13. Lateralization and Contralateralization specialization of the hemispheres
corpus callosum
Right hemisphere
Control LEFT side of body
Music
Non–linguistic sounds
Patterns recognition
Visual and spatial skills
Left hemisphere
Control RIGHT side of body
Language
Analytic reasoning
Time
Arithmetic

14. Lateralization and Contralateralization Split Brain Patient with Commissurotomy

15. Evidences of contralateralization
1. Split–brain patients
Corpus callosum is
surgically severed, i.e.,
no communication
between left and right
Hemispheres.
Blindfolded patient cannot
say the name of the object
put in his/her left hand.

16. Evidences of contralateralization
2. Dichotic
listening test
Non-linguistic sounds
are processed quickly
when heard by the left
ear, while linguistic
sounds are processed
quickly when heard by
the right hear

17. Evidences of contralateralization
3.Hemispherectomy Hemispherectomy involving the left hemisphere results in Aphasia To minimize the damage, brain mapping will precede the operation

18. Brain Mapping

19. Left hemisphere of human brain
Language Center (on the left hemisphere)
Broca’s area: organizes the sound patterns of language
Wernicke’s area: comprehends words
Arcuate fasciculus: nerve fibers connecting Broca and Wernicke’s area to allow information sharing
Angular gyrus: converts visual stimuli into auditory stimuli

21. Aphasia Stroke TBI (Traumatic Brain Injury) Aneurism
Aphasia is an impairment of language. An acquired communication disorder that impairs a person’s ability to process language, but does not affect intelligence.
Possible causes:
Stroke
TBI (Traumatic Brain Injury)
Aneurism

22. Aphasia Broca’s Aphasia Wernike’s Aphasia Conduction Aphasia
Global Aphasia
Alexia,
Agraphia

23. Broca’s Aphasia Identified by Paul Broca, Neurologist, 1861
Patient "Tan": intelligent, good language comprehension, severe deficit in speech production
Postmortem: brain showed selective damage at junction of frontal, parietal, temporal lobes, left hemisphere

24. Broca’s Aphasia: Lesion Site

25. Broca’s Aphasia Caused by damage to Broca’s area
An expressive disorder (telegraphic speech, difficulty forming complete words)

26. Wernike’s Aphasia Identified 1873 by Carl Wernicke
Patient with reasonably good speech, very poor language comprehension
Autopsy showed selective damage in rear parietal/temporal region, left hemisphere

27. Wernicke’s Aphasia: Lesion site

28. Wernicke’s Aphasia Caused by damage to Wernicke’s area
Comprehension disorder (trouble understanding and interpreting lexicon, incoherent speech)

29. Conduction Aphasia
The arcuate fasciculus: a bundle of nerve fibers connecting Wernicke’s area to Broca’s, is essential for normal language function. Damage to it causes conduction aphasia.
Speech is“fluent”, auditory comprehension relatively good, but repetition of heard words is impaired.

30. Global Aphasia Produce few recognizable words
Understands little or no spoken speech
Can neither read or write
Usually seen after patient has suffered a stroke and may rapidly improve if the damage has not been too extensive. Greater brain damage, more severe and lasting disability.

31. Aphasia Alexia: an inability to read and comprehend written words
Agraphia: an inability to write words