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The effects of an experimental sports drink (Q) were compared with a commercial sports drink (D) of proven ergogenic efficacy. Seven highly trained subjects performed two hours of cycle ergometry exercise at approximately 65% maximal aerobic power (VO2 max) while receiving levels of Q and D in quantities designed to supply approximately 28% of the total energy requirement of the exercise task. Both Q and D formulations were supplied at 15 minute intervals at 16 degrees C, in volumes required to provide equivalent carbohydrate loads from two products of differing concentrations and compositions. Q was equally as effective as D in terms of the maintenance of plasma glucose concentrations during exercise, while selected physiological indices of work performance favoured Q. However, the time course of plasma glucose concentration changes during and after exercise indicated a trend towards more rapid uptake and assimilation of carbohydrate in the case of Q. The findings suggest that Q may provide a more readily available carbohydrate source during exercise and may enhance work performance through its ergogenic properties.

The purpose of the present study was to investigate metabolic responses to submaximal and maximal exercise performed with trained versus untrained muscles. The subjects were 17 male college students randomly assigned to one of two experimental groups. Group II (N = 8) performed high intensity arm cranking exercise on a modified bicycle ergometer and Group II (N = 9) performed high intensity bench stepping with arms at sides to a height of 50·8 cm. Both groups trained three days per week for ten weeks. Each subject was tested twice at the beginning and twice at the conclusion of the ten week period. Discontinuous tests (5 min bouts) for determination of submaximal and maximal oxygen uptake ([Vdot]o2 max ) were randomly assigned and performed on bicycle and arm crank ergometers. respectively. [Vdot]o2 max (ml kg−1 min−1) significantly increased (19%) and submaximal heart rate (EKG) significantly decreased during arm testing of arm trained subjects. Similar results ( [Vdot]o2 max ml kg−1 min−1, incr...

The hearing of subjects participating in psychoacoustic experiments may be elevated (temporary hearing loss) due to environmental noises encountered prior to their arrival at the test site. Hearing threshold levels of trained subjects were measured immediately upon arrival at the Laboratory and again following individual 1/2, 1, and 2 hour periods in the quiet of an anechoic chamber. Comparisons of prequiet and postquiet thresholds revealed a slight trend of 1 or 2 decibles toward improved hearing after quiet. However, the changes in hearing thresholds were not statistically significant and were judged to be too small to be of practical significance.

Previous research on self-hypnosis has concentrated on the relationship between heterohypnosis and either self-directed self-hypnosis or self-initiated self-hypnosis. Despite widespread use of audiotapes to assist the process of self-hypnosis, no previous research has compared tape-assisted and self-directed self-hypnosis. Forty-eight inexperienced volunteers were hypnotized and taught self-hypnosis by posthypnotic suggestion and immediate practice in the office. They were randomly assigned to one of two experimental orders to practice self-directed and tape-assisted self-hypnosis. No differences were found between heterohypnosis or either type of self-hypnosis in response to behavioral suggestions. Experiential ratings, however, consistently favored heterohypnosis over either type of self-hypnosis. Tape-assisted self-hypnosis was consistently evaluated as superior to self-directed practice by newly trained subjects.

The present study assessed generalization of training effects using a video computer system (VCS) as a training medium for modifying acuity. Eighteen myopic volunteers were matched according to pre-training acuity and assigned to either fading and feedback training group or a practice only control. Subjects were pre- and post-tested on three measures: the Snellen Letter Chart, a Behavioral Acuity Test and a performance test with the VCS. Compared to controls, trained subjects displayed significant improvements in acuity on the Behavioral Acuity Test. These results suggest that training effects generalize to untrained stimuli. Implications for the clinical implementation of behavioral training procedures for modifying myopia are discussed.

The present study was undertaken to examine whether or not there were any differences between untrained and trained subjects in the changes of blood flow in the ipsilateral and contralateral lower limbs after isometric exercise. Blood flow of the thigh and calf in both right and left legs were measured simultaneously before and after isometric contraction with mercury-in-silastic strain gauge venous occlusion plethysmography. In the present study, the main pattern of blood flow responses in the active and non-active limbs was strikingly similar in all subjects: a significant fall in blood flow immediately after isometric contraction at a force of about 50% of maximal muscle strength for 15 sec was observed in the non-active lower limbs. Peak blood flow of the exercised thigh in the trained group was significantly higher than that in the untrained ones. From these results, it was suggested that higher blood flow after isometric exercise in the trained subjects may be due to the improvement of degree of vasodilation in the lower limb as a result of physical training.

1. 1. Measurements were made of the blood-debt repayments in the calf of 4 untrained subjects after they had run each of three distrances, 220 yards, 880 yards, and 2 miles, at a constant speed of 8.5 m.p.h. under natural conditions on an open-air track. Similar observations were made in a group of 4 athletes. 2. 2. A marked postexercise hyperemia occurred in both groups of subjects after all distances. 3. 3. In the untrained subjects, blood-debt repayment increased with distance up to 880 yards and remained constant with further increase in distance. 4. 4. In trained subjects the blood-debt repayment also increased with distance up to 880 yards, but after 2 miles it dropped to a level significantly lower than that after 880 yards. 5. 5. Blood-debt repayments are similar after a run of 880 yards at 8.5 m.p.h. and after a walk of the same distance at 5 m.p.h. 6. 6. It is concluded that at this speed of running there is no progressive build-up of metabolite either in trained or untrained subjects, although this does not exclude the possibility of such a build-up occurring at greater speeds.

Previous work and theories on the audiogyral illusion ( AGI ) were discussed. An experiment was performed on four trained subjects in order to test the hypothesis that the AGI results from a change in felt head posture during angular acceleration. In general, the results supported the hypothesis.

Protection against the effects of headward acceleration afforded by immersion in water has been assayed in the human centrifuge on 15 trained subjects. Immersion in water to the xyphoid afforded an average protection of 1.1 ± 0.1 G for vision and ear opacity and of 1.6 ± 0.2 G for ear pulse and heart rate. Deeper immersion, to the level of the third rib at the sternum increased the protection to 1.8 ± 0.1 G for vision and ear opacity and to 2.8 ± 0.2 G for ear pulse and heart rate. The protection afforded the various physiologic variables increased with the magnitude of acceleration tested. Protection against loss of consciousness may be greater than protection against blackout and is probably similar to the protection afforded the ear pulse and heart rate. The cardiovascular reactions produced by headward acceleration are qualitatively similar with and without water immersion. This finding does not support the concept that impediment to venous return is the primary determinant of man's tolerance to headward acceleration. Visual symptoms occurred at greater amplitudes of ear pulse, and presumably also at greater blood pressures at head level, during water immersion than during control runs. vision; arterial pressure; heart rate; venous return; arterial pulse in ear Submitted on May 13, 1963

Hues perceived in two-primary projections were predicted for all combinations of pairs of 31 different spectral primaries by use of our computerized version of the Helson–Judd formulation. The computer was instructed to note the absence from the predicted hues of any of the full possible complement of red, yellow–red, yellow, green–yellow, green, blue–green, blue, and red–blue. Experimental confirmation of the computations is reported, based on color naming by trained subjects of the cells in computer-generated quilts projected with a selection of near-spectral primaries. The results of these investigations confirm the usefulness of the Helson–Judd formulation as a means of translating from chromaticity to perceived color in colored displays.

On three trained subjects the effects of some drugs on a) the maximum oxygen consumption, b) the time of performance in an anaerobic exercise, c) the blood lactic acid, and finally d) the maximum heart rate, have been studied. The exercise was a run on a treadmill at 12 alternately 13.8 km/h on a 5% incline carried until exhaustion (ab. 5–6 mins).

Reaction time is measured from the onset of a signal flash to the manual release of a microswitch. Responses are made by two trained subjects over wide ranges of stimulus intensity and under varying conditions of signal flash and background field luminance. Two types of experimental conditions prevail: (1) variable flash luminance at each of three field levels, and (2) variable field luminance at three constant flash intensities. Thirty-six reactions are collected for every flash-field combination at each of two fixation positions (foveal and peripheral).The results are described by the following equation: T=1B logI/I0+K,where B, I0, and K depend upon the field luminance.

1. 1. The techniques of cross-spectral analysis have been applied to tremor of the outstretched fingers recorded simultaneously from both hands of eighteen healthy subjects and at repeated intervals in two trained subjects. 2. 2. The coherence between the tremor wave forms of the two hands was negligeable, averaging only about 0.03 in the group of subjects studied. There was no consistent phase relationship between the tremors of the two hands. 3. 3. The observed coherence between hands rarely exceeded the spurious coherence inevitable in statistical analysis of a finite sample. 4. 4. The absence of significant coherence between the tremor wave forms of the two hands is incompatible with the hypothesis that tremor arises from a common source such as cardiac thrust, or from a single tremor “pacemaker” in the central nervous system. 5. 5. There was a significant relationship between the over-all amplitudes of tremor, peak frequencies and relative sizes of peak of tremor of the two hands in the group of subjects studied and usually in the individual. Such similarities are not the result of a common origin for tremor, but suggest that many of the factors affecting tremor act on both arms to the same degree.

RESULTS reported earlier1–5 have suggested that acquired information can be transmitted to naive animals by giving them material extracted from the brain of trained subjects. In most of these experiments, as in others6–11, transfer of information was suggested by varying degrees of statistical probability and it was challenged by negative results obtained in other laboratories12.

The study sought to determine whether operational communications personnel can rate their performance in transcribing voice radio messages partially embedded in noise with sufficient precision for the ratings to have potential operational utility. Eight experienced communications operators rated their confidence in the accuracy of their reception and transcription of messages received at three signal-to-noise ratios (-6 db, 0 db, +6 db), using a five-point rating scale. As a control, subjects also received and transcribed the messages without making ratings. Measures of transcript accuracy and expressed confidence in transcription were compared with results from a prior study in which subjects had no formal training or experience in communications or transcription. Experienced operators were highly successful in judging their own accuracy, the relationship between confidence and accuracy being r sub tet = .78. Some overconfidence at the upper end of the rating scale and underconfidence at the lower end were evident. Intelligibility improved from 20% to 88% as signal-to-noise ratio increased. The communications operators performed better than the non-communications trained subjects in the former study both in accuracy of transcription and in precision of confidence ratings. Judging the transcription did not affect the average accuracy of the transcripts in either study. In both studies, subjects tended to make effective use of less than all five points of the confidence rating scale.

This study was designed to measure the effect of various signal-to-noise ratios on the comprehension of electrolaryngeal speech by sophisticated and naive subjects, and the effect of training on naive subjects. It was hypothesized: (1) a 9 dB signal-to-noise ratio listening condition would permit the subjects in all three groups to maintain a high degree of comprehension of the electrolaryngeal speaker's message; (2) reducing signal- to-noise ratios would produce a difference between the intelligibility scores obtained by the sophisticated group and the untrained naive group; (3) naive trained subjects would maintain intelligibility scores not significantly different from those of the sophisticated subjects across the three listening conditions. Video training and task tapes were used to provide training and measure intelligibility. Scores from subject performance were analyzed statistically and the conclusions were: (1) a 4 dB signal-to-noise ratio produced a high intelligibility function; (2) below 4 dB listeners demonstrated a decrease in ability to comprehend; (3) no significant difference was found between 4 and 9 dB conditions; (4) trained naive subjects did not score significantly different from sophisticated subjects.

Publisher Summary This chapter explains the different aspects of senses and communication. In some studies of hand–eye adaptation of trained diver subjects in contrast with the untrained subjects, there is a recovery period in which the trained subjects showed remarkable deterioration in hand–eye coordination, and this apparently persisted for quite a while. The subjects wore normal diving masks because of distortion as a result of the normal face mask. The overestimation apparently occurs at distances beyond 4–5 ft and is apart from the usual magnification, which accounts for the data at lesser distances. In otolaryngology, sudden deafness in the non-diving population is frequently seen. There is the possibility that vascular insufficiency plays a real role, whether on the basis of intravascular sludging, intravascular bubble formation, or localized spasm of the end artery.

We examined the effect of resistance training on the response of mixed muscle protein fractional synthesis (FSR) and breakdown rates (FBR) by use of primed constant infusions of [2H5]phenylalanine and [15N]phenylalanine, respectively, to an isolated bout of pleiometric resistance exercise. Trained subjects, who were performing regular resistance exercise (trained, T; n = 6), were compared with sedentary, untrained controls (untrained, UT; n = 6). The exercise test consisted of 10 sets (8 repetitions per set) of single-leg knee flexion (i.e., pleiometric muscle contraction during lowering) at 120% of the subjects’ predetermined single-leg 1 repetition maximum. Subjects exercised one leg while their contralateral leg acted as a nonexercised (resting) control. Exercise resulted in an increase, above resting, in mixed muscle FSR in both groups (UT: rest, 0.036 ± 0.002; exercise, 0.0802 ± 0.01; T: rest, 0.045 ± 0.004; exercise, 0.067 ± 0.01; all values in %/h; P< 0.01). In addition, exercise resulted in an increase in mixed muscle FBR of 37 ± 5% (rest, 0.076 ± 0.005; exercise, 0.105 ± 0.01; all values in %/h; P < 0.01) in the UT group but did not significantly affect FBR in the T group. The resulting muscle net balance (FSR − FBR) was negative throughout the protocol ( P < 0.05) but was increased in the exercised leg in both groups ( P < 0.05). We conclude that pleiometric muscle contractions induce an increase in mixed muscle protein synthetic rate within 4 h of completion of an exercise bout but that resistance training attenuates this increase. A single bout of pleiometric muscle contractions also increased the FBR of mixed muscle protein in UT but not in T subjects.

Several studies analyzed the effectiveness of cold-water immersion (CWI) to support recovery after strenuous exercise, but the overall results seem to be conflicting. Most of these studies analyzed only short-term recovery effects, whereas the adaptational aspect has been widely neglected. Therefore, we analyzed the effects of repeated cooling after training sessions (CWI) on adaptations to strength training. Seventeen trained male students volunteered the study. After a 2-week familiarization period, a pretest (T1) of 1 repetition maximum (RM) and 12RM was conducted followed by the 5-week strength training period (within-subject design). After the posttest (T2) and a 2-week detraining period, a retention test (T3) was carried out. Directly after each training session, CWI was applied for 1 randomly assigned leg. Cooling consisted of 3 4-minute intervals with a 30-second rest period. The other leg was not cooled. A significant increase in 1RM and 12RM from baseline to T2 and T3 (p < 0.001), respectively, and a further significant increase in 12RM from T2 to T3 (p ≤ 0.05) were observed. In addition, a tendency for a large leg effect with higher values for the "control leg" in both parameters (p = 0.08 each) and a moderate time × leg interaction in favor of the control leg was found (1RM: p = 0.11; 12RM: p = 0.09). The percentage change differences between both conditions were 1.6% for the increase in 1RM from T1 to T2 and 2.0% from T1 to T3 in favor of the control leg. Long-term strength training adaptations in trained subjects can be negatively affected by CWI. However, effects were small, and the practical relevance relative to possible recovery effects needs to be considered in a sports practical setting.

The Gjessing (GE) and the wind resistance (Concept II, CII) rowing ergometers were compared in 11 trained subjects during incremental exercise. Maximum power was 255 (200-370) W on GE, but 294 (204-393) W in CII (median and range, p < 0.05). If power was directly measured by a strain gauge and a displacement transducer in the CII, a 5.1% (3.2%-7.8%) higher maximum performance was obtained (314 [223-413] W, p < 0.05). Maximum stroke rates were higher in GE (33 [27-37]/min) than in CII (29 [24-35]/min, NS). Blood lactate increased faster with work rate and lactic anaerobic threshold was therefore lower in GE. Blood lactate was higher for every heart rate for GE compared to CII. This suggests higher anaerobic effort in GE rowing.

Background Zeolites are crystalline compounds with microporous structures of Si-tetrahedrons. In the gut, these silicates could act as adsorbents, ion-exchangers, catalysts, detergents or anti-diarrheic agents. This study evaluated whether zeolite supplementation affects biomarkers of intestinal wall permeability and parameters of oxidation and inflammation in aerobically trained individuals, and whether it could improve their performance. Methods In a randomized, double-blinded, placebo controlled trial, 52 endurance trained men and women, similar in body fat, non-smokers, 20–50 years, received 1.85 g of zeolite per day for 12 weeks. Stool samples for determination of intestinal wall integrity biomarkers were collected. From blood, markers of redox biology, inflammation, and DNA damage were determined at the beginning and the end of the study. In addition, VO2max and maximum performance were evaluated at baseline and after 12 weeks of treatment. For statistical analyses a 2-factor ANOVA was used. Results At baseline both groups showed slightly increased stool zonulin concentrations above normal. After 12 weeks with zeolite zonulin was significantly (p

Getting to know the capacities and limitations of the reasoning brain can help us to understand why some learning situations are efficient while others are not. Brain imaging techniques can offer this information, hence current neuroscience is inclined to use service-learning methodologies which include emotion when measuring mental and brain learning efficiency. In this paper we collect results from empirical research on logico-emotional training based in control by inhibition strategies. This strategy consists in training subjects in self-instructions to avoid falling into the perceptive pairing bias. Results show an increase in the percentage of success from 10% to 90% of the trained subjects, as opposed to subjects trained with other methodologies commonly used in the classroom. As a conclusion, it has been shown that brain activity hints of metacognition imply a deeper and more successful learning experience in the teacher/pupil diad.Key words: Social competence, Young, Older persons, Computer technology, Social abilitiesResumen.Conocer las capacidades y limitaciones del cerebro que razona puede ayudarnos a entender por qué algunas situaciones de aprendizaje son eficaces y otras o no. Las imágenes cerebrales proporcionan esta información de modo que la neurociencia actual se inclina por metodologías de enseñanza-aprendizaje que incluyen la emoción al apreciar su eficacia a nivel mental y cerebral. En este artículo se recogen los resultados de investigaciones apoyadas en el entrenamiento logicoemocional fundamentado en la estrategia control por inhibición. Esta estrategia consiste en entrenar al sujeto en autoinstrucciones para impedir que caiga en la trampa de sesgo de emparejamiento perceptivo. Los resultados muestran un aumento de porcentaje de éxito de un 10% a un 90% en los sujetos entrenados en este tipo de práctica, frente a sujetos entrenados con otro tipo de metodologías utilizadas frecuentemente en las escuelas. Conclusión, “sentir la sensación de lo que sucede” conlleva una experiencia de aprendizaje más comprometida y exitosa en la díada maestro/aprendiz.Palabras clave: Control por inhibición, Metacognitivo, Neurociencia, Lógicoemocional.

This study examines the effect of beer assessment training on verbal and nonverbal performance. Two groups of subjects are asked to sort, match, and describe a set of 12 beers (6 supplemented and 6 commercial beers). Subjects from the first group are enrolled in a beer-training program. Subjects in the second group are untrained beer consumers. Results show that although both groups perform the matching task equally well, trained subjects performed better on supplemented beers and untrained subjects on commercial beers. Examination of the generated vocabulary shows that 44% of the terms are common to trained and untrained subjects. However, an analysis of the terms' efficiency shows that whereas for trained subjects, precise terms are more efficient than intensity or hedonic terms; the opposite is observed for untrained subjects. This suggests that it is not the term itself that is important but the common reference associated to it. Les roles des panels d'experts dans les industries est important en developpement mais aussi en controle de routine pour maintenir la qualite du produit. Ils sont selectionnes pour leur habilite sensorielle et entraines a decrire les caracteristiques des produits, a les differencier et a mettre en evidence leurs defauts. Cette etude examine l'effet de l'entrainement a l'evaluation sensorielle de la biere sur les performances verbales et non verbales. 2 groupes de sujets doivent trier, opposer, decrire une serie de 12 bieres (6 supplementees et 6 commerciales). Les sujets du premier groupe sont engages dans un programme d'entrainement d'evaluation sensorielle de la biere. Les sujets du second groupe sont des consommateurs non entraines. Les resultats montrent que la principale difference entre les 2 groupes est la qualite du vocabulaire utilise.

In 8 trained subjects (T) and 9 untrained subjects (UT), lipid peroxidation (LPO), total antioxidant capacity (TRAP), superoxide dismutase, catalase, and glutathione peroxidase (GPx) activities were measured in the blood before and after three different intensities of exercise on the treadmill, determined from ventilatory threshold and maximal oxygen uptake data, obtained from a maximal aerobic power test. In plasma, LPO decreased from 3589 ± 193 to 3274 ± 223 cps•mg Hb−1(p −1trolox (p −1•mg protein−1) and high (21.75 ± 4.91 to 12.1 ± 2.46 nM•min−1•mg protein−1) intensities (p −1) and moderate (8.89 ± 0.98 to 10.44 ± 0.86 U SOD•mg protein−1) intensity in UT (p

Highly trained subjects completed 500 trials under a signal detection rating scale procedure that tested visual sensitivity at five phases of the menstrual cycle under light and dark adaptation. Sensitivity was reliably increased at ovulation under dark adaptation. In contrast with this, light-adapted sensitivity did not change with phase. Previous research has not shown this pattern of result.

Frequency discrimination for the seventh tone in ten‐tone sequences was examined in a same‐different delayed comparison procedure with highly trained subjects. Performance for interstimulus intervals (ISIs) of 8 or 16 sec was compared for blank ISIs vs ISIs containing interpolated tonal stimuli. Unlike some recent reports, the level of performance observed for a blank ISI was not reduced by interpolated stimuli or an interpolated task. The parameters included similarity of the interpolated stimulus to the standard, presence or absence of a decision task, and placement of the interpolated stimuli and task in the ISI. The result suggests that the capacity for brief auditory memory for nonverbal material may be organized differently from that serving verbal memory. [This research was supported by NINDS Grant No. NS03856 and NIGMS Grant No. GM1900.]

Localization in the median horizontal plane for a speech shaped noise was evaluated under varying degrees of occlusion for 25 trained subjects, all with normal hearing. Binaural test conditions were (1) unoccluded; (2) occluded, ear plug; (3) occluded, earmuff; (4) occluded, helmet; and (5) occluded, helmet with faceplate. The object of these conditions was to measure the degradation of localization ability for speech shaped noise when wearing earplugs, muffs, or helmets. The subjects' task was to center a noise signal in the median horizontal plane to a visual reference point fixed @ 0° azimuth, see [J. D. Harris, Acta Otolaryngol. Suppl. 298 (1972)]. Significantly worse localization occurred with the helmet conditions as compared to all others, followed in turn by performance with earmuffs, then plugs and finally unoccluded. Localization performance was negatively correlated to overall attenuation of the various test devices. This indicated that spectral shape of the sound source, modified by the insert...

Although tests made on aviators and other observations at high altitudes indicate that O2-lack causes sensory disturbances,1 particularly in vision, no systematic study seems to have been made in which the influence of various O2- and CO2-tensions was investigated in regard to sensory functions. Such a study seems to be of particular interest since the importance of these factors for various reflexes is well known. The present paper is based upon 96 audiometer experiments carried out on 6 thoroughly trained subjects. The administration of various O2-, N2- and CO2-air mixtures, which were inhaled from several large Douglas bags, was preceded and followed by control periods in which the threshold for a certain sound was determined in intervals varying between 1 and 4 minutes. Long control series extending over several hours were also carried out in order to determine the spontaneously occurring variations in threshold. The observation room was nearly sound proof.In 37 experiments the influence of breathing ...

Pitch discrimination data for pure tones have been obtained for two trained subjects at frequencies of 250, 1000, and 4000 cps. Two psychophysical procedures were used: In one method (Munson and Gardner's ABX procedure) the subject votes whether the third in a series of three tones sounds more like the first or the second of the series. In the second method (used extensively by Harris) the subject is presented with a standard tone followed by a test tone, and he judges whether the test tone is higher or lower than the standard. The difference limens measured by the second method are for both subjects smaller (by a factor of two or more) than those found by the ABX procedure. This fact gains in significance since one subject has small DLs while the other has rather large ones. Judgmental data obtained from a limited choice situation can provide at best an upper bound for so-called ultimate sensory capacity. Practically speaking, the second method not only yields smaller DLs, but is also easier on the subje...

An intensive study of the attenuation properties of numerous ear protectors and the statistical treatment of the data obtained, explains and/or documents many previously suspected or noted irregularities in measurement procedures. Detailed data on subjective measurement, directionality, linearity, and asymmetry of attenuation of ear protectors were collated. These findings will be presented along with a description of the nonparametric statistics used to ascertain central tendencies, sources and magnitudes of variability, and degrees of correlation of the data. In the study, nine ear protectors, 10 trained subjects, and two artificial heads were utilized. The USA Standards Institute's method (i.e., free‐field threshold shift) was used to obtain subjective measurements. The artificial heads were employed for the acquisition of detailed information on the noise‐exclusion properties of each ear protector.

Threshold measurements were made by two automatic audiometers; (1) continuously variable frequency tracing audiometer with an attenuation step of 0.25 dB; (2) continuously changing discrete individual frequency tracing audiometer with an attenuation step of 1.0 dB. Five trained subjects with bilateral normal hearing, four subjects with unilateral cochlear lesion, and four subjects with unilateral retrocochlear lesion were tested. For both pulsed and continuous tones, there was no observable difference in thresholds between two audiometric measurements for subjects with bilateral normal hearing and for ears with normal hearing in subjects with unilateral hearing impairment. The ears with cochlear lesion indicating abnormal rapid adaptation showed slightly greater separation between pulsed and continuous tone thresholds by continuously variable frequency tracings than by continuously changing discrete frequency tracings. For the ears with retrocochlear lesion indicating abnormal slow type of adaptation, muc...

The effects of element speed and element pitch contour were studied for synthetic vowels /i, ae, a, u/ in various permuted sequences. Four trained subjects were asked to identify temporal order in this closed response vowel set. A high‐level stimulus uncertainty procedure was used. Subjects were near perfect performance at element durations ranging from 90–150 ms. They were above d′ = 1.0 level at 30 ms per element and d′ = 2.0 at 60 ms per element. Performance on individual sequence permutations varied little at 90–150 ms per element but varied between chance and slightly above d′ = 2.0 at both 30 and 60 ms per element. The effect of normalizing element pitch contours was negligible for individual sequence permutations at all element speeds. The duration threshold of vowel sequence identifiability (125–200 ms per element) reported by other investigators using a recycling presentation format is considerably longer than these 30–60 ms per element thresholds. A more sensitive approach to determine absolute d...

It has been generally accepted that during exercise at sea level, the pulmonary system of normal, healthy individuals is capable of maintaining arterial oxygen tension at near resting levels. However, recent evidence questions whether this generalization applies to the highly trained endurance athlete who is capable of achieving very high levels of metabolic demand. Hence, the purpose of these experiments was to examine the relationship between maximal oxygen consumption (VO2max) and arterial oxygen-hemoglobin saturation (%SaO2) during short-term heavy exercise in trained athletes and untrained individuals. Ten trained distance runners and 7 untrained males exercised at 95% of VO2max for 3 min. Minute-by-minute measurement of %SaO2 was obtained via ear oximetry. The correlation coefficients between %SaO2 and VO2max during exercise were r = -0.68, r = -0.74, and r = -0.72 (P less than 0.05) for minutes 1 through 3, respectively. In general those individuals with the highest VO2max showed the greatest decrease in %SaO2. By comparison there was no difference (P greater than 0.05) in resting %SaO2 between the trained (96.3 +/- 0.2% [SE]) and the untrained (96.3 +/- 0.4%) subjects. However, at minute 3 of exercise, %SaO2 was significantly lower (P less than 0.05) in the trained subjects (87.0 +/- 0.7%) than in the untrained subjects (92.6 +/- 0.7%). These data demonstrate that arterial desaturation occurs in healthy, highly trained endurance athletes during heavy exercise and that the level of the arterial desaturation is inversely related to VO2max.

Composers' pulses are patterns of expressive microstructure (i.e., timing and amplitude modulations) said to convey individual composers' personalities when implemented in computer performances of their music [see M. Clynes, in Studies of Music Performance, edited by J. Sundberg (1983), pp. 76–181]. The present research continued the perceptual evaluation of such pulses, which so far has yielded inconclusive results [B. H. Repp, Music Perception (in press)]. The initial bars of five piano pieces by each of four composers (Beethoven, Haydn, Mozart, and Schubert) were played on a computer‐controlled electronic piano with each of the four composers' pulses (following Clynes' specifications as closely as possible) and also in a deadpan version. Listeners judged to what extent each computer performance conveyed the composer's characteristic expression, relative to the deadpan version. Pilot results provide occasional positive support for the Beethoven and Haydn pulses, but none at all for the Mozart and Schubert pulses. Additional data will be reported from musically trained subjects who also listened to computer performances in which the timing and amplitude components of the pulses were applied separately. [Work supported by NIH‐BRSG.]

The terms consonance and dissonance refer to subjective impressions of musical sounds. No studies have examined perception of consonance with stimuli other than two‐note chords. Naive and musically trained subjects rated the degree of consonance and dissonance (both smoothness and pleasantness judgments) of major, minor, diminished, and augmented three‐ and four‐note chords. These chords were presented in root position, first inversion, and second inversion and varied in their harmonic structures and intonations. Naive subjects were strongly influenced by harmonic structures of chords. Neither group of subjects made judgments contingent on the intonation system used. Both naive and musically trained subjects rated major chords as most consonant, followed by minor, diminished, and augmented chords. These patterns occurred in all conditions and were most pronounced for musically trained subjects. When all of the harmonics were present, root‐position chords were rated as most consonant and second inversions least consonant. These findings are discussed in terms of theories of consonance and dissonance.

During rounded vowels the outer end of the vocal tract may be modeled as an ellipse in the plane perpendicular to the midline. But in other vowels the termination of the vocal tract has a more complex shape because the corners of the lips are not in the same plane as the opening in the midline. in order to investigate appropriate ways of modeling lip actions, three trained subjects were recorded and photographed while saying pairs of vowels such as [i, y; e, o; Ɯ, u]. In saying each pair subjects took care to hold the tongue position steady and to move only the lips. For each of the rounded vowels a computer model was set up with the observed lip opening and the vocal tract shape that produced the best match to the observed formant frequencies. With this vocal tract shape maintained, the lip opening was then set to that observed in the corresponding unrounded vowel. By varying the distance of the lip opening from the glottis, a program found the best acoustic match to the unrounded vowel. The results indicate the way in which the apparent location of the termination of the vocal tract varies with lip opening.

We report upon exemplary measurements of group‐delay distortions as induced into electroacoustical transmission by the fact that earphones and loudspeakers are not necessarily minimum phase systems. Additional psychoacoustical tests showed that the measured distortions are on the order of the limit of perceptibility or exceed this limit. The limit of perceptibility of group‐delay distortions depends strongly upon the kind of signal, the shape of the group‐delay curve, and the state of training of the subjects. For short sound pulses and group‐delay distortions as produced by second‐order all‐pass filters we found in diotic presentation, with one all‐pass at frequencies between 1 and 4 kHz, a limit of group‐delay perceptibility between 1 and 2 msec for untrained subjects and 0.4 msec for trained subjects. Further experiments with up to 20 all‐pass filters showed that for group‐delay curves with multiple maxima and minima the limit of perceptibility has a value of about 0.6 msec (peak to valley) for trained subjects.

The three Lisker—Abramson CV series (ba‐pa, da‐ta, ga‐ka) were computer synthesized at C.I.D. in 1‐msec steps. For each 84‐trial block of a high‐uncertainty, same‐different task (no feedback), one of the three continua was chosen at random. On each trial, the ability of three naive listeners to resolve for differences among VOT pairs ranging from VOT = 10–80 msec, in 10‐msec steps was tested. As expected, there was a local maximum performance for each of the three speech continua, thus satisfying one criterion for categorical perception. A minimum‐uncertainty AX task (with feedback) was run with three highly trained subjects for the ga‐ka continuum. Only one standard VOT was presented in a block of trials. Results were not categorical: the minimum detectable ΔVOT was less than 2 msec at VOT = 10 msec and increased as VOT increased. Our results indicate that trained listeners can utilize subtle stimulus cues in synthetic speech if stimulus uncertainty is minimized. [Supported by a grant from NINCDS.]

Acoustical correlates of stress can only be evaluated in comparison with some “standard” specifying which syllables are actually stressed. The standard should be consistent from time to time, and largely independent of talker and listener idiosyncrasies. Three phonetically trained subjects listened repeatedly to spoken texts and spontaneous sentences, until they could categorize each syllable as either stressed, unstressed, or reduced. This procedure was repeated three times for each speech text and listener. Two listeners differed from each other on only about 5% of all syllables as to whether they were perceived as stressed or not. Each also showed only about 5% confusions in decisions about stressed syllables from one trial to another. Unstressed and reduced levels were much more frequently confused. The third listener gave less consistent results. Subjects' judgments of stress when given only the written text were of comparable consistency, but did not correspond well with perceptions with speech, if the speech was spontaneous rather than spoken texts. Stress perceptions consequently may be suitable for evaluating acoustical correlates to within a 5% tolerance in overall location scores. Pooling the perceptions from several trials and several listeners may improve the stability of this “standard” for stress assignment.

A new illusion is described, produced by presenting two repeating sequences of Shepard tones, one to each ear. Each tone consisted of several sinusoidal components separated by octaves, and the tones were generated under various fixed spectral amplitude envelopes. The pitches were as in the scale illusion [D. Deutsch, J. Acoust. Soc. Am. 57, 1156–1160 (1975)], omitting those standing in octave relation. Thus B‐E‐G‐G‐E‐B was presented to one ear, while D‐A‐F‐F‐A‐D was presented to the other ear. Musically trained subjects notated separately the sequences that they heard in each ear. Most subjects reorganized the tones in accordance with pitch proximity, so that they obtained the illusion of B‐A‐G‐G‐A‐B in one ear, together with D‐E‐F‐F‐E‐D in the other ear. The apparent locations of the two sequences were often independent of the positioning of the earphones. Further, the subjects generally reported the two sequences as in different octaves. Analogous effects were obtained with binaural presentation of simultaneously ascending and descending Risset glides. [Work supported by NIMH.]

A series of experiments designed to investigate the “precedence effect” in lateralization space were conducted using a two‐alternative, forced‐choice paradigm. Stimuli consisted of 40‐μs transients separated by inter‐click intervals (ICIs) of 0.38f–30 ms. In a two click paradigm (experiment 1) interaural differences of time (IDT) thresholds were determined independently at click positions 1 and 2. Thresholds measured at click 2 ranged from 12 μs at extended (over 5 ms) and short duration (less than 1 ms) ICIs to a peak of 250 μs at ICIs of 1.75–2.35 ms. Thresholds measured at click 1 were uniform across ICIs, constant at approximately 15–25 μs. Experiment 2 consisted of a three click paradigm where the ICI between clicks 2 and 3 was held constant at a value where subjects in experiment 1 had peaked (1.75–2.35 ms), while the ICI between clicks 1 and 2 was varied from 0.38 to 10 ms. IDT thresholds were measured for click 3. Results show a U‐shaped function for which thresholds drop below 30 μs for click 3 at ICIs between 2–8 ms, with the effect returning at long and short duration ICIs. Experiment 3 consisted of click trains of n = 2, 3, 4, 5, 6, and 12 where ICI was held constant at subjects' peak value in experiment 1 and IDT thresholds were measured at the last click in the train. Results show a negatively decelerating function as n increases, wtih IDT thresholds falling from 250 down to 20 μs. The most dramatic find in these series of experiments, however, was the surprising yet compelling dissipation of “suppression” in the temporal window of interest (1‐ to 5‐ms ICIs) over multiple runs. Thresholds fell by 5 to 10 folds, matching values reported by Perrott et al. (in press) in the free field. Across variations of stimulus duration, form, intensity, or frequency, highly trained subjects showed no recovery of the precedence effect. [Work supported by NSF and NIH.]

Certain patterns of pitch, such as chords and scales, are central to the organization of traditional music. These patterns are identified by standardized nomenclature, and form a basis for analytical listening to music. The auditory processes involved in recognition may be revealed by comparing the ability of trained subjects to categorize these standard patterns. Perceptual confusion among standard, three‐tone stimuli was studied in 19 musically trained subjects. A solid‐state organ, interfaced to a digital computer, was used to present the stimuli; a terminal connected to the same computer was used to collect the responses. All subjects received the same stimuli, randomly accessed by the computer program. The subject indicated whether the signal presented was major, minor, augmented, or diminished. The three‐note signals were presented in three manners: simultaneously, ascending (in pitch), and descending. All stimuli were presented at both O.2‐ and 0.1‐sec note duration. Accuracy wan least for shorter ...

In a four‐level 2AFC paradigm, trained subjects had to discriminate time intervals that were marked by tone bursts of unequal duration (10 and 100 msec). Time differences discriminable at the d′ = 1 level, ΔTThresh, were determined in the 10–100‐msec range of time intervals (onset to onset). When the frequencies and intensities of all markers were held constant (1 kHz and 86 dB SPL), ΔTThresh was a monotonic function of T. This relation became non‐monotonic when the level of the first marker was decreased to 36 dB SPL or as the two marker frequencies were made different from each other by two octaves. Thus, a discrepancy in either the level or the spectrum of two time‐marker sounds may constitute an acoustic basis for the nonmonotonic VOT discrimination functions, despite the fact that the depth of the local minimum found in the present data is less than that observed in VOT experiments. [Supported by a grant from NINCDS.]

Factual evidence that is slowly being accumulated both in this country and in Canada, although it is as yet meager, shows that nutritional deficiency disease prevails in many parts of the country. 1 Sebrell 2 believes that it is no exaggeration to say that at least one third of the American population is eating a diet which is not adequate in all respects. Basing our judgment on the requirements which modern nutritionists consider as optimum nutrition, not mere adequacy, we believe that widespread improvement in health is possible. The evidence of malnutrition is not restricted to low income groups or families on relief but is just as apt to be found in the middle and upper class families. Although it was suspected that the average American diet might be well below the optimum in certain essential nutrients, there was no means of proof available until the classic publication of Stiebeling

Speech‐spectrogram pattern‐matching experiments were conducted on the members of an 8‐family population. A 5‐word vocabulary was excerpted from normal and whispered narrative speech for each member of the 8 families, which consisted of father, mother, and a 5‐ or 6‐yr‐old son. Trained subjects were able to select the proper parents of children for 28% of the attempts. When children were matched with parents separately, the success was 17.5% with mothers and 21.5% with fathers. Husbands were spectrographically matched with wives correctly in 23% of the attempts. The chance expectancy of a correct match in the above data was approximately 2.0%. Sufficient evidence of familial influence in speech patterns was found to suggest that a more sophisticated experiment be performed.

Four trained subjects listened to successive sequence bursts, each burst consisting of three component items (filtered 1000‐Hz square wave; noise band, 2500‐Hz tone) repeated several times without pauses between items, until they decided whether alternate bursts had these items in the same or different order. Prior training consisted of listening to known same or different sample sets as requested by the subject until he indicated readiness to receive these sets as unknowns. Same/different recognition was significantly above chance for at least half of the subjects at each of three interburst intervals (50 msec, 1.5 sec, 3 sec) for item durations from 5 through 400 msec. With items shorter than 100 msec, the order could not be identified, and judgments were based on pattern “quality.” In separate experiments with single stimulus bursts, four listeners were trained by receiving immediate feedback concerning their accuracy in identifying (naming) order. For two item sequences (square wave and noise), correct identification was obtained for item durations from 5 through 400 msec. When these stimulus pairs were preceded and followed by a tone of the same duration as the test items, accurate identification was obtained for item durations from 10 through 400 msec. [Research supported by NSF.]