Speech Production PDF

Chapter1 Speech Production All the sounds we make when we speak are the result of muscles contracting. The muscles in the chest that we use for brcathing produce the flow of air that is nccded for almost all speech sounds; muscles in the larynx produce many differ...

Chapter1 Speech Production All the sounds we make when we speak are the result of muscles contracting. The muscles in the chest that we use for brcathing produce the flow of air that is nccded for almost all speech sounds; muscles in the larynx produce many different modifications in the flow of air from the chest to the mouth. After passing through the larynx, the air goes through what we call the vocal tract, which ends at the mouth and nostrils; we call the part comprising the mouth the oral cavity and the part that lcads to the nostrils the nasal cavity. Here the air from the lungs escapes into the atmosphere. We have a large and complex set of muscles that can produce changes in the shape of the vocal tract, and in order to learn how the sounds of speech are produced it is necessary to become familiar with the different parts of the vocal tract. These different parts are called articulators, and the study of them is called articulatory phonetics. Stages in the Production of speech Raal pugla FOUR STAGES hebatd oante. nlCniy Jnitiation Par Toeg pkonation Oral-nasal process Articulation CamScanner 1 The initiation process InEnglish (and most cother other lan , all oeech sOunds reguire: langdortheir production. The airstream used for speech is always moving out of the lungs and up to the trachea vELLAM Pulmonicegressive 2 The phonation process At the upperend of the trachea, the air passes through the lary The larvnx contains the vocal folds, The space between the vocal folds is called glottis. This is where the process of phonation occurs. Glottis CamScanner 2 The phonation process Closed glottis: The vocal folds are brought together so that no air can pass between them. The resulting sound is called glottal stop. In some accents of English, the glottal stop can replace the sound /t/ in s like football, bottle, bit, etc. 2 The phonation process The vocal folds can be manipulated by the speaker and brought into different positions: Narrow glottis. When the vocal folds are brought together insucha way that only a narrow space is left for the air to pass through, the passage of air makes them. The resulting sound waves characterise voice SOunds. Thyr Caatilage Glotat Slit Catilane Catilan (n) voicing CamScanner  4 The articulation process the the airgoes into ether of these cavities, am produce the different English consonants. For example, when producing the sound /p/, the lips come together and and the air is relased with a puff of air. When producing the /m/the airis released different articulators to produce different sounds. The flow of air from the lungs during speech differs in several important respects from the airflow during quiet breathing. 1. during speech, three to four times as much air is exhaled as during quiet breathing. 2.In speech the normal breathing rhythm is changed radically (basicly): inhalation i more rapid and exhalation is much more drawn out. 3. The number of breaths per unit of time decreases during speech. 4.The flow of air is unimpeded during quiet breathing, whereas in speech the airflow encounters resistance from the obstructions and closures that occur in the throat and mouth. the function of breathing(exchange of oxvgen and carbon dioxide) continues with no discomfort to the speaker. Cs CamScanner  Mechanisms for expanding the lungs during both quiet breathing and speech ne ction of the (a sheet of che diaphragm (ity m Cular from the abdominal region) This contraction causes the diaphragm to lower and flatten out, leading to an increase in the size of the chest cavity. 2. The set of muscles between the ribs In the rib cage (the external intercostals) Air also flows inward when the muscles between the ribs (the external intercostal9 contract and the rib cage expands outward, thus increasing the size of the chest cavity Espkaian Contraction of these muscles causes the ribs to lift up, and because of the way that the ribs are hinged, they swing out, increasing the volume of the chest cavity. Since the lungs are attached to the walls of the chest cavity, when the chest cavity expands, either from diaphragm contraction or from rib movement, the lungs, being elastic, also expand. As the lungs expand, air flows in, up to the point when inhalation is completed CamScanner  During quiet breathing the diaphragm relaxes at this point, and During speech, however, the muscles of the stretched lungs begin to shrink, the diaphragm and the rib cage continue allowing air to flow out quite to be active, restraining the lungs from rapidly at the beginning. as with air escaping from a filled emptying too rapidly. balloon. RESPIRATION Oung ORs utn The Larynx & vocal tract Definition of the Larynx Also known as the "voice box," the larynx is important for breathing, speaking, and swallowing. The larynx is an organ made of bone and cartilage located in the center of the throat and contains the glottis. A structure of muscle and cartilage located at the upper end of the trachea (or windpipe) The first point where the airflow from the lungs encounters a controlled resistance. The resistance can be controlled by the different positions and tensions in the vocal cords (or vocal folds), two muscular bands of tissue that stretch from front to back within the larynx For speech the most important feature of the vocal cords is that they can be made to vibrate if the airflow between them is sufficiently rapid and if they have the proper CamScanner tension and proximity to each other. This apid vibration is calledI voicing v (or phonation). The frequency of vibration detemines the perceived pitch. The larynx is partially visible from the outside of your body. If you have a prominent "Adam's apple," you can sec it pretty casily the larynx is a delicate organ with many small parts. Each part serves a particular purpose. Epiglottis The topmost part of the larynx is the epiglottis. The epiglottis a picce of cartilage attachcd to the basc of the tonguc that protccts the windpipe when swallowing. Think of the cpiglottis as the "lid" of your larynx. When you swallow, it flaps over the a your top of r larynx to keep food and drink from entering your windpipe. IIf vou've ever laughed while cating or drinking and been scnt into a coughing fit, it's because the epiglottis didn't have time to close off the larynx before anything entered it. This allowed the food or drink to "go down the wrong pipe." Trachea The trachea is the lowest part of The trachea is a tube of membrane tissue and cartilage that connects the larynx to the lungs In other words, the trachea is the windpipe. This tube allows you to breathe through your nose and mouth. 9 CamScanner