Speech Science Final

• Acoustics is the study of sound
• Aerodynamics is the study of airflow
• Physiology and Kinematics involve the study of motion
• Dynamics focus on the forces that cause movement
• Psychoacoustics explores the relationship between physical properties of sound and perception
• Instrument measurement is a part of the study
• The source and medium must have mass and elasticity
• Fundamental Physical Quantities include:

  • Mass (m): the amount of matter something has
  • Weight is mass + gravitational pull
  • Air has mass and weight
  • Density = mass/volume
  • Affects magnitude of inertia
  • Length: the amount of spatial separation between two points
  • Time
• Derived Physical Quantities:

  • Displacement: a change in position (both distance and direction)
  • Velocity: displacement over time
  • Acceleration: change in velocity over time
  • Force: "push" or "pull"
  • Pressure: Force per unit area
• Physical properties of source and medium:

  • Density = mass/volume
  • Elasticity: restoring force
  • Momentum is directly proportional to mass and velocity (M=mv)
• Newton's Laws of Motion:

  • First Law: Inertia
  • Second Law: when a net force acts on an object, the object accelerates in the same direction as the force
  • Third Law: for every action (force), there's an equal and opposite reaction
• The Energy Principle states that energy is the capacity to do work
• Respiration Process:

  • Involves the expansion and contraction of thoracic cavities by the diaphragm and external intercostals
  • Air flows in due to the negative pressure between the parietal and visceral pleural walls
  • Phonation process involves the cycle of vibration of vocal folds
• resonator: something that is forced into vibration by another vibrator (sound sources)
• Resonators modify sound and they have a natural resonant frequency
• Mechanical resonators: object is forced into vibration
• acoustic: the air inside an object that is forced into vibration
• tidal volume: the total amount of air inhaled and exhaled in breath cycle
• residual volume: amount of air remains in lungs after mass exahle
• inspiratory volume: the volume of air that can be inhaled after tidal expiration
• expiratory reserve volume: the amount of air that can be exhaled after tidal expiration
• Vital capacity: the amount of air exhaled after deep inhale
• Functional residual capacity: amount of air in lungs after normal exhalation
• total lung capacity: amount of air lungs are capable of hold
• Boyles law: increase in volume, less pressure (vice versa)
• extended phonation: inspiratory muscle activation to slow exhalation for speech
• checking action: muscular activity which prevents the recoil forces of lungs
• control bigger breath with subglottal pressure by using more laryngeal effort and controlling respiratory airflow
• functions of the larynx: protect, push/pull, pulmonary function
• mucosal wave in phonation: proceeds inferior to superior cycle of VF vibration
• Phonation process: VF adduct, expiration starts (until medial compression overcomes VF), VFs blow apart (puff of air escapes), VFs sucked back together (Bernoulli effect), the cycle repeats
• VF vibration is affected by mass (more mass, less vibration), stiffness (higher stiffness, more vibration), length ( longer VF vibrate lower)
• Intensity depends on Medial Compression of Vocal Folds, length of closed phase of VF, amplitude, SP created
• VF cause resistance to airflow
• measuring aerodynamic properties of phonation: pressure, subglottal, intraoral, airflow, transglottal
• ohm's law: flow = air pressure/resistance
• Acoustic of voice: intensity and F0
• Perturbation: shimmer, jitter, and noise to harmonic ratio
• shimmer: cycle-to-cycle variability in VF vibration in amplitude
• Jitter: cycle-to-cycle variability in VF vibration in frequency