The Effect of Psychophysical Method on the Loudness of Continuous and Interrupted Pure Tones

1979 ◽  
Vol 22 (4) ◽  
pp. 717-730
Author(s):  
Dennis Hampton ◽  
Ira M. Ventry

Using the Bekesy tracking method for loudness judgment tasks such as most comfortable loudness (MCL) and recalled loudness (RL) measurements, normal listeners have tracked continuous (C) tones at lesser intensities than interrupted (I) tones. The resulting continuous/interrupted (C/I) separations have ranged up to 22 dB. Explanations of the unexpected C/I separations have not been in agreement. The purpose of this study was to investigate whether psychophysical method has a significant effect on the C/I separation. Subjects were six normal-hearing adults, each of whom participated in three practice and ten test sessions of one hour each. Thirty-six experimental conditions were presented. The test signals were C tones, 200/200 msec I tones and 200/800 msec I tones, all at 1 kHz. The reference intensities were 20, 50 and 80 dB SPL. The four methods were Bekesy tracking method (BTM), method of adjustment (MAdj), method of limits (ML) and method of constant stimuli difference (MCSD). Mean values for Point of Subjective Equality and C/I separation were calculated. C/I separations obtained with the BTM were significantly larger than C/I separations obtained with any other psychophysical method. These results demonstrate that C/I separations obtained during suprathreshold Bekesy tracking tasks by normal hearers are largely caused by the measurement method itself rather than by differences in C and I tone loudness. Time order errors could explain the BTM effect.

Perception ◽  
1986 ◽  
Vol 15 (3) ◽  
pp. 313-324 ◽  
Author(s):  
Victor J Manyam

Quantitative estimates of the spatial discriminative capacities of the visual and kinaesthetic systems in adults and children were obtained. Intersensory integration was investigated by including spatial discriminations based on congruent visual plus kinaesthetic reafference. The psychophysical method of adjustment was used with simultaneous comparisons of a fixed and a variable stimulus. The subject's task was to estimate when the variable stimulus (ellipse) was identical to the standard one (circle), under one of three modality conditions: vision, kinaesthesis, and vision plus kinaesthesis. After a pilot study with adults, children (aged 8, 10, and 12 years) and adults were both tested. Subjects from each age group were randomly allocated to each of the three experimental conditions. Results show that the visual and kinaesthetic estimates of the 8- and 10-year-old subjects did not differ significantly, but the visual responses of the adults and 12 year olds were significantly more accurate than corresponding kinaesthetic estimates. Bisensory estimates were significantly more accurate than visual responses only for the 8- and 10-year-old age groups. Intramodal comparisons showed the kinaesthetic estimates of the 8, 10, and 12 year olds to be significantly more accurate than the corresponding adult performance. Adult visual estimates were significantly more accurate than those made by 8 year olds, but were not significantly different from the visual responses of 10 and 12 year olds. Estimates based on bisensory reafference did not differ from each other across the four age groups. It is concluded that modality adeptness and dominance are task dependent and empirically determined rather than being innate properties of sensory systems. The data indicate that intersensory differentiation rather than integration occurs with maturity.


1980 ◽  
Vol 23 (3) ◽  
pp. 630-645 ◽  
Author(s):  
Gerald Zimmermann ◽  
J.A. Scott Kelso ◽  
Larry Lander

High speed cinefluorography was used to track articulatory movements preceding and following full-mouth tooth extraction and alveoloplasty in two subjects. Films also were made of a control subject on two separate days. The purpose of the study was to determine the effects of dramatically altering the structural dimensions of the oral cavity on the kinematic parameters of speech. The results showed that the experimental subjects performed differently pre and postoperatively though the changes were in different directions for the two subjects. Differences in both means and variabilities of kinematic parameters were larger between days for the experimental (operated) subjects than for the control subject. The results for the Control subject also showed significant differences in the mean values of kinematic variables between days though these day-to-day differences could not account for the effects found pre- and postoperatively. The results of the kinematic analysis, particularly the finding that transition time was most stable over the experimental conditions for the operated subjects, are used to speculate about the coordination of normal speech.


2005 ◽  
Vol 22 (3) ◽  
pp. 389-399 ◽  
Author(s):  
Marc Pouliot ◽  
Simon Grondin

One of the features of the auditory system is its ability to efficiently process events that occur in rapid succession. The aim of the present study is to propose a new way of investigating sensitivity to auditory tempo changes. More specifically, it proposes to compare the relative sensitivity (bias) to acceleration and deceleration in both musical and monotonal conditions. Bias was measured with (1) a conventional psychophysical method known as the method of constant stimuli (MCS) and (2) a so-called method of dynamic stimuli (MDS). The latter method consists in responding with a finger press as soon as a near-continual tempo change is detected. With the MCS, there was no preference, as estimated by the point of subjective equality, between acceleration and deceleration in the monotonal condition, but there was a preference in the musical condition that indicated more facility for estimating decelerations than accelerations. The results obtained with the MDS are consistent with the MCS results, given that the response time was faster for decelerations than accelerations in the musical condition but not in the monotonal condition. We conclude that the MDS is a sensitive tool for investigating slight tempo variations.


2005 ◽  
Vol 19 (2) ◽  
pp. 134-138 ◽  
Author(s):  
Anna Carolina Aguiar Cassanho ◽  
Aletéia Massula Fernandes ◽  
Luciane Dias de Oliveira ◽  
Claudio Antonio Talge Carvalho ◽  
Antonio Olavo Cardoso Jorge ◽  
...  

The aim of this study was to evaluate in vitro the antimicrobial activity of glass ionomer (GIC) and zinc oxide-eugenol (ZOE) cements against Candida albicans. Standardized GIC and ZOE specimens were maintained in contact with C. albicans suspension (1 <FONT FACE=Symbol>´</FONT> 10(6) cells/ml) at 37°C for 24 h, 48 h or 7 days. A control group without any testing cement was included. After the incubation period, aliquots of 0.1 ml were plated on Sabouraud's agar, and then the number of colonies was counted. The results were expressed as values of logarithms of colony-forming units per milliliter (log CFU/mL) and were analyzed statistically by Kruskal-Wallis ANOVA. After 48 h of incubation, the ZOE group presented no growth of C. albicans. GIC and control groups presented similar mean values at all tested periods. According to the results obtained, it could be concluded that, under the experimental conditions, ZOE cement was more effective in vitro against C. albicans than GIC.


2020 ◽  
Author(s):  
Juanjuan Wang ◽  
HaoRan Yang ◽  
Ning Xu ◽  
Chengqin Wu ◽  
ZengShun Zhao ◽  
...  

Abstract The long-term visual tracking undergoes more challenges and is closer to realistic applications than short-term tracking. However, the performances of most existing methods have been limited in the long-term tracking tasks. In this work, we present a reliable yet simple long-term tracking method, which extends the state-of-the-art Learning Adaptive Discriminative Correlation Filters (LADCF) tracking algorithm with a re-detection component based on the SVM model. The LADCF tracking algorithm localizes the target in each frame and the re-detector is able to efficiently re-detect the target in the whole image when the tracking fails. We further introduce a robust confidence degree evaluation criterion that combines the maximum response criterion and the average peak-to correlation energy (APCE) to judge the confidence level of the predicted target. When the confidence degree is generally high, the SVM is updated accordingly. If the confidence drops sharply, the SVM re-detects the target. We perform extensive experiments on the OTB-2015 and UAV123 datasets. The experimental results demonstrate the effectiveness of our algorithm in long-term tracking.


1980 ◽  
Vol 35 (5-6) ◽  
pp. 431-438 ◽  
Author(s):  
Peter Dancker

Abstract ATPase activity and ATP-Pi exchange of unregulated (without tropomyosin-troponin) and regulated (with tropomyosin-troponin) acto-HMM were measured in media containing 0.2 mg/ml actin, HMM, and (when present) tropomyosin-troponin, 2 mM MgCl2, 10 m M KCl, 2 mM NaN3, 10 mM Pi(pH 7.0), 3 mM ATP. The following mean values for ATPase activity and for the rate of incorporation of P, into ATP (each per mg HMM and per min) were obtained: unregulated acto-HMM 0.33 nmol Pi and 0.33 nmol Pi, regulated acto-HMM 0.54 nmol Pi and 1.06 nmol P*. The ratio of P4 incorporation rate to ATPase activity was 1.01 × 10-3 for unregulated and 2.02 × 10-3 for regulated acto-HMM. From these ratios and from the overall free energy change of ATP hydrolysis it was calculated that under the prevailing experimental conditions in unregulated acto-HMM 62% and in regulated acto-HMM 66% of the free energy change of ATP hydrolysis occurs after the release of phosphate from actomyosin. It is probably this part of the free energy change that is used by the muscle for the performance of work.


1950 ◽  
Vol 2 (1) ◽  
pp. 33-41 ◽  
Author(s):  
W. E. Hick

The difference threshold for the velocity of a seen object was measured by the method of constant stimuli, using two categories. An approximate correspondence with Weber's law was found, the divergence from it appearing, in general, as an increase of the threshold at both ends of the range of initial velocities. The Mean Threshold (0·5 probability of perception, corrected for guessing) was, in favourable conditions, about 12 per cent, of the initial velocity. Whether the stimulus was an increase or a decrease of velocity made no marked difference. With two moving objects, which converged, crossed, and then diverged, both suffering the same change of velocity, the threshold was higher. Velocity changes as low as 2 · 5 per cent, elicited a significant proportion of correct responses. Some theoretical points in connection with this are discussed. Responses to blank stimuli showed a strong tendency to guess “slower,” which tendency differed significantly in degree between most of the experimental conditions. Tests with reduced exposure times showed that exposures could be as short as 0 · 5 second (the velocity change occurring in the middle of the exposure) without appreciable detriment.


1980 ◽  
Vol 24 (1) ◽  
pp. 643-646
Author(s):  
Marian E. Benton ◽  
Robert P. Bateman

Twenty-five subjects performed tracking tasks with the right arm before and after cranking a bicycle ergometer with the left arm. Three experimental conditions consisted of cranking the ergo-meter for 60, 90, and 120 seconds. The results indicate there was a significant decrement in tracking performance the first ten seconds after each of the cranking periods. By thirty seconds after cranking, tracking performance returned to pre-cranking level for each of the conditions. The decrement was not attributable to heart rate or breathing rate increases which remained for periods of up to five minutes. The crossover fatigue effect warrants further study.


1937 ◽  
Vol 3 (2) ◽  
pp. 169-176 ◽  
Author(s):  
C. McC. Mottley

The European species of Salmo have fewer vertebrae than those from western North America, the mean values of two of each group as reared at the Cowichan hatchery being found to be: salar 59.0, trutta 58.3, gairdnerii 63.5, clarkii 62.5. Hatchery-reared gairdnerii were usually found to be different from those of the natural environment as well as varying with different experimental conditions, and even differed from their own parents, this seeming on the whole to be related to the temperature during development. A correlation was found between the length of the fish and the number of vertebrae. Caution is suggested in the use of the character for identifying populations of Salmo.


1975 ◽  
Vol 18 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Dale O. Robinson ◽  
John H. Gaeth

Seven normal-hearing subjects and seven subjects with mild bilateral high-frequency sensorineural hearing losses were studied to explore the presence of diplacusis. A tracking procedure of psychophysical method of adjustment-limits was used for pitch judgments rather than the traditional method of adjustment. Each subject was presented with a standard 4000-Hz tone for 500 msec and alternately a variable tone for 500 msec. Subjects were instructed to adjust the variable tone upward or downward in pitch to bracket the pitch sensation of the standard tone. Two intra-aural and two interaural listening conditions were studied. A graphic representation of the subjects' adjustments of the variable tone was obtained for each condition. The resulting tracing indicated frequency correlates to the pitch adjustments from which excursion width and constant error were calculated. Some hard-of-hearing subjects and one normal-hearing subject were found to have diplacusis. Subjects with hearing losses exhibited larger excursion widths for intra- and interaural listening conditions. Subjects with hearing losses tended to be less consistent in pitch judgments than normal-hearing subjects. These findings were interpreted to mean that bilaterally symmetrical hearing losses increase the incidence of pitch aberrations.


Sign in / Sign up

Export Citation Format

Share Document