Vocal pedagogy Respiratory Anatomy

Respiratory system Lungs provide airflow which is the power/fuel for the voice Essential to life Part of the autonomic nervous system- so happens without conscious thought Provides oxygen for body function and disposes of waste carbon dioxide.

Structure of the lungs Trachea, left and right bronchus to bronchioles then alveoli. There are between 20 and 30 generations of branches. Left has 2 lobes and right has 3 Between the lungs is the mediastinum a space containing the heart, trachea oesophagus and blood vessels. The surface area of the alveoli is a similar size to a tennis court and so allows rapid exchange of gases.

Lobes of lungs

Structure of the lungs The lungs are encased in a double plural membrane. This is one continuous sac which doubles back on itself. The Visceral Pleura adheres to the lungs and the out parietal pleura encases the chest wall. The intrapleural space contains a lubricating fluid. It is not a real space but a place of negative pressure keeping the two membranes adhered together. The fluid allows the membranes to slide over each other easily during expansion and contraction with breathing.

Action of the lungs The negative pressure means that the surface tension keeps the two surfaces together preventing the lung from collapsing. Air is drawn into the lungs through the nose or mouth, through the larynx and trachea. The trachea is a flexible tube made up of rings of cartilage. The rings are incomplete giving flexibility to the tube.

Airflow Air moves into an area of lower pressure created by the mechanical expansion of the ribs The trigger to inhale comes from the medulla of the brain in response to receptors detecting the presence of CO2 Blowing a balloon positive pressure Emptying a balloon higher pressure of air inside created by “walls” of the balloon

Action of bellows

Skeletal support of the lungs The spinal column is divided into 5 areas. Each part has numbered vertebrae Cervical - C1-7 Thoracic - T1-12 Lumbar - L1-5 Sacral - S1-5 Coccygeal - Cg1-5 Coccyx

Spinal column

Ribs and sternum The thoracic vertebrae provide the attachment of the twelve ribs at the back The Sternum made up of the manubrium, body of sternum and xiphoid process with which the true ribs articulate at the front

Sternum

Rib Cage

False ribs 8-12 The 8-10 pairs of ribs connect to the sternum indirectly via the costal cartilages of the ribs above them. Their elasticity allows ribcage movement for respiratory activity. The phrase floating rib refers to the two lowermost 11 and 12 rib pairs; so-called because they are attached only to the vertebrae–and not to the sternum or cartilage of the sternum. These ribs are relatively small and delicate, and include a cartilaginous tip.

Muscles of respiration

Inspiratory muscles

Quiet Inspiration Diaphragm when it contracts it becomes less domed and flatter increasing the size of the thoracic cavity Question can you put your hand on your diaphragm? External intercostals (note the direction of the muscle fibres.)

Diaphragmatic movement

Rib expansion Upper ribs are hinged with the sternum so they move forwards when raised. This does not increase the size of the lungs as much as lower ribs and is considered inefficient Lower ribs (5 upwards) move more like a bucket handle outwards and upwards

Muscles of forced inspiration Costal elevators Sternocleidomastoid Scalenes Pectorals Latissimus dorsi Levatores costarum Serratus posterior superior

Accessory muscles of inspiration

Expiration Passive at rest Recruitment muscles for Forced expiration Controlled expiration in speech and song

Expiration Muscles of Expiration In “quiet” or “resting” breathing expiration is passive, that is muscle contraction is not required. Muscular activity is encountered when the expiration is “forced” out rapidly, when expiration goes below the resting level, or when the expiratory flow is controlled as during speech breathing. While speaking, muscular force can be used to prevent the ribcage from descending too quickly. The following muscles can be used to forcefully exhale, to exhale below the resting level or to check the expiratory direction of the ribcage. The internal intercostal muscles lie deep to the external intercostals. The muscle fibres run in an opposite direction to the external intercostals - they run down and laterally. The rectus abdominus muscle is a paired muscle which lies lateral to the abdominal midline. The external oblique muscle is a paired muscle which runs in the same direction that the external intercostal muscles travel. As with the external intercostal muscles, placing your hands in your pockets mimics the direction of muscle fibres. The internal oblique muscle is a paired muscle which underlies the external obliques and runs in the opposite direction with fibres originating from the iliac crest and inguinal ligament and inserting into the cartilaginous portion of the lower 4 ribs. The transverse abdominus muscle is a paired muscle that forms the deepest muscular layer of the abdomen. The quadratus lumborum is a quadrilateral-shaped sheet of muscle which runs from the iliac crest and insert into the transverse processes of the lumbar vertebrae and the twelfth rib. As its origin and insertion points suggest, this is a muscle of the posterior abdominal wall.  Useful facts about breathing Usually breathe 12-20 times a minute Inspiration : expiration changes from rest to speech 40 : 60 Rest 10 : 90 Speech with oral breathing  

Active Expiration While speaking, muscular force can be used to prevent the ribcage from descending too quickly. Either to forcefully exhale, or to exhale below the resting level. The internal intercostal muscles which lie deep to the external intercostals act in this way. The muscle fibres run in an opposite direction to the external intercostals - they run down and laterally.

Other muscle of expiration Rectus abdominus muscle External oblique muscle Internal oblique muscle Transverse abdominus. Quadratus lumborum