2. Speech and language

3. significance Social interaction and private intellectual life
Any disturbance due to brain disease- functional loss more grave than blindness, deafness and paralysis

4. language Symbolic representation of objects, actions and events
Mirror of higher mental activity
Means of communication between patient and physician- medium of delicate interpersonal transaction

5. Abilities in which humans surpass other animals
Developing and using verbal symbols for our ideas
Transmitting those ideas by written or spoken word
Facility to use our hands
Both language and manual dexterity are functions of dominant hemisphere

6. Emotional language Seen in other animals – by vocalization or gestures
It is a feeling or reaction of that moment
Earliest modes of emotional expression appear in infancy
Emotional expression is well developed in human infants even when cerebrum is immature

7. Utterances used to express joy, anger, fear are retained even after destruction of all language areas in the dominant hemisphere

8. Symbolic language Essence of language
Means of transferring ideas from one person to another
Learned – subject to social and cultural influences of the environment
Learnt only after nervous system has attained a certain level of maturity

9. Mature language involves comprehension,
formulation and transmission of ideas and feelings
using verbal symbols, sounds, gestures
their sequential ordering according to accepted rules of grammar

10. Needs
Thinking
Analysis
Synthesis
Creativity

11. Speech and language are closely interwoven but not synonymous
Derangement of language reflects an abnormality of brain – specifically the dominant hemisphere
Speech disorder may have a similar origin, but not necessarily; it may be a result of abnormalities in different parts or extracerebral mechanisms

12. Speech refers to articulation and phonetic aspects of verbal expression

13. types of speech Exophasia = external speech
Expression of thought by spoken or written words, comprehension of spoken or written words of others
Almost continuous when humans gather

14. Introphasia = internal speech Silent process of thought and formulation in our minds of unspoken words

15. connections Arcuate fasciculus connects sensory and motor speech areas
Short association fibres connect Broca’s area with lower part of motor cortex that innervates muscles of lips, tongue and pharynx

16. Perisylvian cortical areas connected to
Striatum, thalamus
Corresponding areas in non- dominant hemisphere via corpus callosum and anterior commissure

17. Communication by language involves more than just selecting words and then assembling them according to grammatical rules.
Most of the emotional content, and part of the linguistic content as well, is conveyed by varying emphases.
This is true of language generally, but especially of spoken language

18. Cerebral Dominance and Its Relation to Language and Handedness
There are many ways of determining that the left side of the brain is dominant
by the loss of speech that occurs with disease in parts of the left hemisphere and its preservation with lesions involving corresponding parts of the right hemisphere
by preference for and greater facility in the use of the right hand, foot, and eye;

19. by the arrest of speech with a focal seizure or with electrical or magnetic stimulation of the anterior (left) language area;
by dichotic listening, in which different words or phonemes are presented simultaneously to the two ears (yielding a right ear–left hemisphere advantage

20. by observing increases in cerebral blood flow during language processing
by lateralization of speech and language functions following commissurotomy.

21. anatomic differences between the dominant and the nondominant cerebral hemispheres.
Yakovlev and Rakic, in a study of infant brains, observed that the corticospinal tract coming from the left cerebral hemisphere contains more fibers and decussates higher than the tract from the right hemisphere

22. More pertinent to language, the planum temporale, the region on the superior surface of the temporal lobe posterior to Heschl gyri and extending to the posterior end of the sylvian fissure, is slightly larger on the left in 65 percent of brains and larger on the right in only 11 percent (Geschwind and Levitsky).

23. LeMay and Culebras noted in cerebral angiograms that the left sylvian fissure is longer and more horizontal than the right and that there is a greater mass of cerebral tissue in the area of the left temporoparietal junction.

24. Anatomy of language functionsA
The conventional teaching, based on correlations between various disorders of language and damage to particular areas of the brain, postulates four main language areas, situated in most persons in the left cerebral hemisphere

25. The entire language zone that encompasses these areas is perisylvian, i.e., it borders the sylvian fissure.
Two language areas are receptive and two are executive, i.e., the latter are concerned with the production (output) of language.

26. The main receptive area, subserving the perception of spoken and probably of internal language, occupies the posterosuperior temporal area (the posterior portion of area 22) and Heschl gyri (areas 41 and 42).

27. The posterior part of area 22 in the planum temporale is referred to as Wernicke area.
A second receptive area occupies the angular gyrus (area 39) in the inferior parietal lobule, anterior to the visual receptive areas

28. The supramarginal gyrus, which lies between these auditory and visual language "centers," and the inferior temporal region, just anterior to the visual association cortex, are probably part of the language apparatus as well.
Here are located the integrative centers for crossmodal visual and auditory language functions.

30. The main executive, or output, region, situated at the posterior end of the inferior frontal gyrus (Brodmann areas 44 and 45), is referred to as Broca area and is concerned with motor aspects of speech

31. These sensory and motor language areas are intricately connected with one another by a rich network of nerve fibers
one large bundle of which, the arcuate fasciculus, passes through the isthmus of the temporal lobe and around the posterior end of the sylvian fissure

32. other connections may traverse the external capsule of the lenticular nucleus (subcortical white matter of the insula).
Many additional corticocortical connections lead into the perisylvian zones and project from them to other parts of the brain.

33. Of special importance for the production of speech are the short association fibers that join the Broca area with the lower rolandic cortex, which, in turn, innervates the muscles of the lips, tongue, pharynx, and larynx

34. The perisylvian language areas are also connected with the striatum and thalamus and with corresponding areas in the minor (nondominant) cerebral hemisphere through the corpus callosum and anterior commissure

35. there remains considerable difference of opinion concerning the status of cortical language areas
objection has been made to calling them "centers," for they do not represent histologically or circumscribed structures of constant function.

36. Role of non-dominant hemisphere
Modulative aspects of language
Prosody
Melody of speech
Its intonation, inflection, and its pauses
All these have emotional overtones
Prosody and gestures accompanying them enhance the meaning of spoken word

37. Speech is endowed with richness and vitality
Aprosody is seen in lesions involving inferior division of right Middle cerebral artery

38. The right hemisphere system for generating and comprehending prosody is apparently organized in a fashion analogous to the left hemisphere system for producing and comprehending language.

39. That is, the right inferior frontal gyrus is involved in producing prosody, and the right posterior temporoparietal region in comprehending it

40. One of the first patients described with a deficit related to prosody was a schoolteacher with right frontal damage who began to have difficulty controlling her students because she was unable to convey anger or authority by voice or gesture (even though the feelings were there).

41. She had motor aprosodia.
Patients with more posterior lesions on the right may have sensory aprosodia and have difficulty comprehending the emotional content of the speech or gestures of others.