Speech and language

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. 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

18. Speech is endowed with richness and vitality • Aprosodyis seen in lesions involving inferior division of right Middle cerebral artery