COMD 5070 Exam 1

Scientific Method - answer-empirical, deterministic, predictive, parsimonious Empirical - answer-based on data Deterministic - answer-obeys physical laws Predictive - answer-If you do this, then this will happen Parsiminious - answer-uses the simplest explanation possible Why use technology? - answer-overcome listener bias, describe severity objectively, track progress over time, ASHA's focus on evidence-based practice, provide biofeedback to patient How to overcome listener bias? - answer-consistent, reliable measurements How to track progress over time? - answer-demonstrate treatment efficacy Biofeedback example - answer-vizipitch- allows client to view intonation patterns on a screen so they can see & monitor their own progress Things clinicians can do that technology can't - answer-understand the numbers, examine qualitatively and quantitatively, judgments/ interpreting data Why understand technology? - answer-SLP needs to know normal & disordered physiology; can only provide rational treatment if data is understood; need to know what numbers from instruments represent; provide expert interpretation 3 key arenas of Speech Science - answer-acoustic phonetics, physiologic phonetics, speech perception Physiologic phonetics - answer-kinematics, aerodynamics, electromyography Frequency - answer-how often a waveform repeats; measured in Hz Simplest sounds - answer-pure tones Complex tones - answer-have more than 1 sine wave (more than 1 sound being produced together, & they blend); have many frequencies; F0 = strongest; perceived pitch follows fundamental; human voice has F0 and harmonics; auditory system responds to all frequencies Pitch perception - answer-linked to frequency; order on a musical scale; subjective perception; can't be measured w/ instruments; listener matches perceived pitch to that of a pure tone of a known frequency Frequency Difference Limens (DL) - answer-smallest detectable change in frequency; dls increase w/ stimulus frequency; high frequency sounds must differ more to be heard as different in pitch; as intensity increases, dls become larger Intensity of speech - answer-measured in db SPL Db SPL = - answer-20 (log10 PO/PR) Periodic relationship - answer-if frequencies in a complex tone are in a mathematical relationship to one another such that the harmonics are multiples of the fundamental; if not periodic, sounds jarring/ discordant Missing fundamental - answer-listen to a harmonic series; actual fundamental can be absent; timbre/ quality is different; pitch is still perceived as the same; brain processes harmonic structure & fills gap by calculation/ interpolation; cheap audio equipment- stimulated bass; AKA "residue pitch" Pitch perception in music - answer-A or B sounds equivalent up or down; some note pairs blend harmoniously, some are dissonant; harmonic frequencies match or don't Octave - answer-doubling/ halving of frequency Intensity - answer-measured with a sound level meter; power per unit area Intensity formula - answer-watts/meter squared Loudness - answer-a perceptual characteristic; judged by listener (not right or wrong); linked to intensity by psychophysical scale Magnitude rating - answer-the process of plotting psychological perceptions of intensity Recruitment - answer-an abnormal growth in loudness Effect of frequency on loudness - answer-hearing more sensitive at some frequencies (lowest thresholds from Hz); thresholds increase for lowest & highest frequency sounds; audiometers use HL, not SPL because of the unequal response Linking db & loudness - answer-individual responses vary- influenced by study methodology & instructions to listeners; general rule: 6-10 db increase perceived as twice as loud; individual perception not wrong Duration & loudness - answer-longer tones are more audible Root mean square - answer-mic signals always change, and with them so does amplitude; to measure this, we need to square- makes all values positive; get the average of squared values & get the square root of all the values Acoustic power - answer-measures amount of energy transfer in a given amount of time; measured in watts; describes how much energy is radiated/ transferred by the system Home stereos - answer-are transducers (convert electric energy into acoustic energy); energy output by a stereo system not experienced the same way from different distances; radiates outward from the source in a sphere; as the radius gets bigger, the energy is spread over a much larger sphere Area of a sphere - answer-4πr squared Inverse square law - answer-intensity diminishes in proportion to the square of the distance from the source Regulating speech effort - answer-subglottal pressure drives speech; more driving pressure for loud speech; larger vocal fold excursions (more forceful vocal fold collisions); range of loudness changes w/ pitch; voice range profile; measures db across F0 range; more popular in europe; not as standardized as audiograms Voice range profile (VRP) - answer-measures vocal range; data collection VRP data collection - answer-1) find out client's min & max F0 2) find 10 points along that range; could use linear scale (Hz increments) or a logarithmic scale (in semitones)