Footnotes for Chapter 3

1. Though active pharyngeal expansion normally occurs only during voiced plosives (Chapter 7), it is possible that an unvoiced plosive might also involve a pharyngeal expansion. Such an expansion might be involved in the articulatory dynamics to produce pre- or post-release resonance effects.

2. One nonsense syllable was included to complete a pattern of contrasts. Due to the phonemic nature of the Korean orthography the syllable could be read unambiguously by any literate Korean speaker.

3. The actual circuit used contained some additional components which supplied a small current to compensate for the non-ideal rectifying action of the diode.

4. It has been shown lately that rates of tension buildup higher than that attained in a single twitch can be obtained by stimulating the motor nerve with interstimulus intervals just larger than the refractory period of the nerve fiber system (BULLER and LEWIS, 1965a; MARTENSSON and SKOGLUND, 1964.) Though this phenomenon may be of interest in the study of mechanism of muscle contraction, it is not clear that such interstimulus intervals are attainable in a controlled manner in the body, especially in centrally-mediated movement patterns. The phenomenon becomes significant only with stimulation frequencies of between 100 and 500 pulses/sec, while the most rapid motoneuron activation frequencies recorded have been about 50 pulses/sec (RUCH and FULTON, 1961, p.110; MARTENSSON and SKOGLUND, 1964, p.332). However there has been comparatively little recording from single motoneurons during various types of movements, due to the technical difficulties involved. New techniques for this type of recording are just now being developed (for example PIERCE et al., 1964).

5. Since many comments concerning the 'checking' of respiratory movements are traceable to STETSON's observations, it is interesting to note that much of STETSON's earlier work was concerned with movements of the extremeties, in which the physical inertia is an important factor. The effective inertia in a movement depends not only on the mass of the body being moved but on its acceleration. It is possible that STETSON failed to recognize that the acceleration of the respiratory structures in speech is small compared to the acceleration of the extremeties in most body movements.

6. For example, the voltage increase generated by the R-L-C-diode circuit of Figure 3.5.1,with switch S₂ closed, might have been slightly more appropriate.