Magnitude-estimation Responses Research Articles

Magnitude-estimation scaling of computerized (digitized) speech under different listening conditions.

The purpose of this study was to evaluate the quality of tape-recorded speech sentences and speech sentences digitized at low, moderate, and high sampling rates by young adults under different listening conditions (quiet vs noise) using magnitude-estimation scaling. A single group of 24 young adults participated as subjects. The tape-recorded speech sentences and digitized speech sentences were presented to each subject in quiet and in the presence of background noise at a signal-to-noise ratio of 0 dB. The subjects were instructed to use magnitude-estimation scaling to evaluate these sentences by assigning a number that corresponded to the speech quality of each sentence. An analysis of variance with repeated measures was performed to assess the effects of mode of speech and listening condition on the magnitude-estimation responses. The analysis showed that the main effects for mode of speech and listening condition were statistically significant. The interactions of mode of speech by listening condition were also statistically significant. Pairwise comparisons showed that the magnitude-estimation responses were higher in the quiet condition than in the corresponding noise condition for each level of mode of speech. Based on the results, the implications of the present study and several avenues for later research are discussed.

Hearing threshold shift during auditory magnitude estimation.

The purpose of the present experiment was to determine the extent of hearing threshold shift that may occur during an auditory magnitude-estimation task involving stimulus intensities as great as 80 dB sensation level. Also, possible influences of hearing threshold shift on numerical magnitude-estimation responses and magnitude-function slopes were investigated. Results indicated that hearing threshold shift was insignificant (1-2 dB). Consistent small increases in numerical magnitude responses were observed on a magnitude-estimation task where hearing thresholds were retested between stimulus presentations versus a magnitude-estimation task where hearing thresholds were not retested. The stability of auditory magnitude functions across different conditions in the current investigation was in agreement with vibrotactile magnitude-scaling behavior observed by Fucci, et al. in 1989 and 1991. The over-all results supported the concept of an absolute, internal sensory-scaling mechanism being operable during magnitude estimation of auditory stimuli as discussed by Zwislocki and Goodman in 1980.

Magnitude-Estimation Scaling of Speech Intelligibility: Effects of Listeners' Experience and Semantic-Syntactic Context

Fifteen speech-language pathologists with extensive experience judging speakers' intelligibility and 15 control subjects with no such previous experience provided magnitude-estimation responses for two sets of nine audiotaped speech samples. These samples were three utterances composed of a group of 17 words that contained all the consonant phonemes of English. These words were arranged to form a set of either meaningful or nonsense utterances. Nine separate versions of both the meaningful and nonsense utterances were created by systematically increasing the number of phonemes produced incorrectly on each of the nine recordings. The analysis indicated no significant difference between the magnitude-estimation scaling responses of experienced and inexperienced listeners. A significant over-all difference was found for listeners' responses to meaningful versus nonsense utterances. The advantages of magnitude-estimation scaling as a measure of speakers' intelligibility are discussed.

Lingual Vibrotactile Threshold Shift during Magnitude-Estimation Scaling: Effects on Magnitude-Estimation Responses and Scaling Behavior across Age

The purpose of this study was to investigate the effects of age on tactile threshold shifts occurring during magnitude-estimation scaling of vibratory stimuli presented to the dorsal surface of the tongue. Relationships of the lingual vibrotactile threshold shifts to suprathreshold stimulus intensity, magnitude-estimation responses, and over-all scaling behavior were explored. Three groups differing in mean age participated in this study (Group 1 8.05 yr., Group 2 19.46 yr., and Group 3 56.2 yr.). Each subject performed two magnitude-estimation tasks. In one task, threshold of sensitivity was measured after every suprathreshold numerical response to the subject. If a threshold shift was recorded, threshold was allowed to return to the pretest baseline level continuing to the next suprathreshold stimulus presentation. The results showed that threshold shift during magnitude-estimation scaling took place for all three age groups and that the shift was related to the intensity of the suprathreshold vibratory stimulus being applied to the tongue. They also showed that Group 2 (young adults) performed magnitude-estimation scaling differently when threshold shift was controlled than when it was not. The other two groups of subjects were not similarly affected.

Vibrotactile threshold shift during magnitude-estimation scaling on the hand; effects on magnitude-estimation responses and scaling behavior : D. Fucci, L. Petrosino and S. Wagner 1989 Perceptual and Motor Skills69, 187–194. (8 pages, 1 figure, 0 tables, 20 references) (in English)

Vibrotactile threshold shift during magnitude-estimation scaling on the hand; effects on magnitude-estimation responses and scaling behavior : D. Fucci, L. Petrosino and S. Wagner 1989 Perceptual and Motor Skills69, 187–194. (8 pages, 1 figure, 0 tables, 20 references) (in English)

Critical bands and mixed-frequency scaling: Sequential dependencies, equal-loudness contours, and power function exponents

Stimuli of random intensities and various but predictable frequencies were presented for repeated magnitude estimations on the same scale (mixed-frequency scaling). The frequencies for a particular judgment session were selected so that they lay either inside each other's critical bands or outside them. Contrastive dependencies of current magnitude estimation responses on previous stimuli of a different frequency were significantly affected by whether the two frequencies were inside or outside each other's critical bands, while assimilative dependencies were not. This reinforces the idea that such dependencies are sensory in nature and arise from a different mechanism than do the assimilative dependencies. Mixed-frequency scaling of loudness also gives rise to cross-frequency matching functions from which equal-loudness contours can be calculated. These contours calculated from the present judgments are similar to those produced from other methods, even when they are extrapolated to untested intensities. Power function exponents for loudness scaled in this way are larger for lower frequencies, as has been found in previous studies, and are consistent with the flattening of the calculated equal-loudness contours for low frequencies as intensity increases.

Using Magnitude Estimation Scaling to Examine the Validity of Nursing Diagnoses

This paper describes the use of magnitude estimation scaling in the validation of the critical defining characteristics of nursing diagnoses. Magnitude estimation is a sensitive and accurate technique producing ratio level scales that offer advantages over ordinal level scales frequently used in validating nursing diagnoses. Magnitude estimation responses permit a consensus pattern to be achieved by producing stable and repeatable judgments to validate the importance of each sign and symptom investigated. Thus, magnitude estimation shows promise as a methodologic strategy for validating the critical defining characteristics of nursing diagnoses, thereby expanding the effort to identify and classify nursing phenomena.

Speech Clarity/Intelligibility: Test-Retest Reliability of Magnitude-Estimation Scaling

The reliability of magnitude-estimation scaling as a measure of overall clarity of speech was investigated. 40 subjects (M age = 19 yr.) provided magnitude-estimation responses for nine audiotaped versions of a nonsense sentence varying systematically in number of correct consonant phonemes. There was no significant difference in the magnitude-estimation responses of the subjects during two test sessions separated by one week. Analysis suggested that magnitude-estimation scaling is a reliable measure of speech clarity/intelligibility. This finding is discussed in relation to speech samples varying in aspects other than number of consonant phonemes correct and possible further clinical research applications.

Vibrotactile threshold shift during magnitude-estimation scaling on the hand: effects on magnitude-estimation responses and scaling behavior.

The purpose of the present study was to determine whether threshold shifts occurred during magnitude-estimation scaling of suprathreshold stimuli presented to the thenar eminence of the right hand. Possible relationships of the vibrotactile threshold shifts to suprathreshold stimulus intensity, magnitude-estimation responses, and over-all scaling behavior were explored. A single group of 14 subjects whose ages ranged from 18 to 22 yr. participated. Each subject performed two magnitude-estimation tasks. In one of the tasks threshold of sensitivity was determined after every suprathreshold numerical response of the subject. If a threshold shift was recorded, threshold was allowed to return to pretest baseline level before continuation to the next suprathreshold stimulus presentation. Analysis showed that threshold shift did occur during vibrotactile magnitude-estimation scaling on the hand and that it was related to suprathreshold stimulus intensity. Results also showed that the subjects' numerical magnitude-estimation responses and over-all scaling behavior in the form of power function exponents were not statistically different for the two scaling tasks.

Lingual vibrotactile threshold shift during magnitude-estimation scaling: effects on magnitude-estimation responses and scaling behavior.

The purpose of the present study was to determine if lingual vibrotactile threshold shifts occurred during magnitude-estimation scaling of suprathreshold stimuli presented to the dorsal surface of the tongue. Possible relationships of the lingual vibrotactile threshold shifts to suprathreshold stimulus intensity, magnitude-estimation responses, and overall scaling behavior were explored. A single group of 24 subjects with an age range of 18 to 22 years participated in this study. Each subject performed two magnitude-estimation tasks. In one of the tasks, threshold of sensitivity was determined after every suprathreshold numerical response of the subject. If a threshold shift was recorded, threshold was allowed to return to the pretest baseline level before continuing to the next suprathreshold stimulus presentation. The results showed that threshold shift did occur during lingual vibrotactile magnitude-estimation scaling, and that it was related to suprathreshold stimulus intensity. The results also showed that the numerical magnitude-estimation responses of the subjects were different for the two scaling tasks. Overall scaling behavior of the subjects in the form of power-function exponents was not different for the two tasks.

Effects of auditory masking on lingual vibrotactile magnitude-estimation scaling responses of young children.

Studies of lingual vibrotactile magnitude-estimation scaling have focused primarily on the responses of normal young adults. Little is known about the scaling responses of young children to suprathreshold vibratory stimulation because of the complexities of the experimental procedure. Binaural auditory masking is one aspect of the procedure that has recently been studied in adults. The purpose of this study was to investigate the effects of binaural auditory masking on lingual vibrotactile magnitude-estimation responses of young children. Four children whose mean age was 4.6 yr. completed magnitude-estimation scaling tasks for eight lingual vibrotactile suprathreshold intensity levels (6, 10, 16, 20, 26, 30, 36, 40 dB SL) under masking and no masking conditions. Results suggest possible effects of auditory masking on the lingual vibrotactile magnitude-estimation scaling responses of these young children that have not been found for such responses of adults.

Circular vection is independent of stimulus eccentricity.

The sensation of self-rotation induced by viewing a surround rotating about the observer's vertical axis (circular vection or CV) was investigated with equal-area stimuli located in either the central, the mid-peripheral, or the far-peripheral visual field. Magnitude estimation responses indicated greater CV with larger stimulus area, but no significant differences in CV sensations as a function of stimulus eccentricity. This pattern of results does not support the belief that CV is dominated by peripheral stimulation when equal-area stimuli are compared.

Stimulus duration effects on vibrotactile magnitude estimation for the tongue and hand

The present study was designed to investigate the effect of stimulus duration on vibrotactile sensation magnitude for the lingual dorsal surface and the thenar eminence of the right hand through use of the psychophysical scaling method of magnitude estimation. Magnitude estimation values for the tongue and hand were derived from 20 normal young adults. Measurements were made at a frequency of 250 Hz with stimulus durations of 100, 500, and 1,000 msec. Results showed the upper power function exponents to be steeper at all three stimulus durations for the lingual dorsal surface than for the thenar eminence, and the exponents for both the tongue and hand were smaller for 1,000 msec than for 100 msec. Pearson product moment correlations were performed on the subject magnitude estimation responses for the three stimulus durations. The durational correlations were performed independently for both test structures. Correlation coefficients for both test structures at all three stimulus durations tended to increase as stimulus intensity was increased. The correlation coefficients did not reflect changes in the relationship between individual subject responses as a result of stimulus durational changes at any of the sensation levels tested. Results are compared to previous research and discussed in terms of internal scaling mechanisms and learning effect.

Effects of exposure to psychophysical scaling on lingual vibrotactile magnitude estimation and magnitude production.

The purpose of the present study was to determine if the results obtained by the scaling methods of magnitude estimation and magnitude production could be influenced by providing subjects with prior exposure to psychophysical scaling in the form of magnitude estimation or magnitude production. Group 1 (n = 10, Mage = 21.1 yr.) performed lingual vibrotactile-magnitude estimation followed by lingual vibrotactile magnitude production. Group 2 (n = 10, Mage = 19.7 yr.) performed lingual vibrotactile-magnitude production (using the magnitude-estimation responses provided by Group 1), followed by lingual vibrotactile-magnitude estimation. For the magnitude estimations there was no over-all statistically significant difference between the two groups, but there was for the magnitude-production values. Magnitude-estimation scaling was apparently not influenced by prior exposure to magnitude production, while magnitude-production scaling was influenced by prior exposure to magnitude estimation. The results are discussed in terms of how subjective scaling behavior in psychophysical experimentation may be influenced by the interaction between an absolute internal scaling mechanism and parameters set by the experimenter, such as scaling method and range of stimulus intensity.