Differential vowel duration associated with children's word-final fricative deletion.

This study assessed whether 3 children, 5 to 6 years old, who deleted word-final fricatives preserve the voicing contrast for those fricatives by producing dif ferential duration of the preceding vowel. The children's CV syllable productions were compared to their CV(C) syllable productions in which the final consonant was intended but actually deleted. Analysis indicated that all 3 children exhibited significantly longer vowel duration, in CV syllables than in CV(C) syllables. This differential duration of the preceding vowel was shown in both isolation and carrier phrase conditions. Of the 3 children 2 preserved the voicing contrast by showing significantly longer vowels preceding voiced consonants as compared to voiceless consonants. One child did this in both isolation and carrier phrase conditions and the other child did this in isolation only. All 3 children manipulated vowel duration to signify the linguis tic contrast, therefore these findings support a linguistic perspective of speech development which focuses on the acquisition and knowledge of the linguistic rules of the language. In addition, the large amount of variability in vowel duration for CV and CV(C) syllables and the marked variability in performance across children support a biological view of a developing vocal tract undergoing structural and physiological changes.

Do different dialytic techniques have different atherosclerotic and antioxidant activities?

To compare the chronic effect of several dialytic techniques (bicarbonate dialysis, BHD; acetate free biofiltration, AFB; hemodiafiltration, HDF; paired filtration dialysis, PFD) on atherosclerosis and antioxidant activity, three different indices were created. The first (atherosclerotic index = AI) is formed using the sum of three plasma substances: MDA, Hcy, and Cys (malondialdehyde, homocysteine, cysteine). The second (antioxidant activity index = AOAI) is the sum of five erythrocyte (E) parameters: E-GSH, GPx, CAT, SOD, GR (E-glutathione, E-glutathione peroxidase, E-catalase, E-superoxide dismutase, E-glutathione reductase). The third (defense index = DI) is derived from the previous two: (AOAI - AI). The indices were so expressed as AI in mmol/L, AOAI in U/g hemoglobin (Hb), and DI in arbitrary units. These indices were calculated in 20 controls and 51 chronic HD patients (26 female, 25 male) before, during, and after the first session of the week. HD patients were divided according to their dialytic technique: BHD, n = 35; AFB, n = 5 patients; HDF, n = 7 patients; or PFD = 4 patients. All patients had been treated with a given technique for at least 12 months, before entering the study. As expected, HD patients had AI values higher than controls, both before and after the session, with a mean value of 541 (before) and 331 (after), whereas controls had a mean value of 205. The AOAI was lower than controls, both before and after the session, the mean value being 1,122 (before) and 1,582 (after), that of controls being 2,424. In all cases, PFD gave the best "acute" results; at the end of a PFD session, near normal values of AI, AOAI, and DI (defensive index = AOAI - AI) were obtained.

A study of the self-talk of adults who do and do not stutter.

This is a preliminary investigation of the differences in positive and negative self-talk reported by groups of people who do and do not stutter. 10 people who stutter, all who had experience with stuttering therapy, were matched with 10 participants who did not stutter. Each participant, in both groups, was engaged in a session to evaluate speech in a format similar to a professional diagnostic session for stuttering. Each participant was asked to stop at specific times during the session and describe thoughts of that moment as either positive or negative. This procedure is similar to thought sampling and in vivo cognitive assessment used in cognitive-behavioral treatments and research. The participants' reports were taken during a baseline period, during a period in which they were thinking about their speech, and during three different speaking tasks. The reports given by the group of people who stutter were compared to the reports given by the group of individuals who did not stutter. Statistical analyses showed no differences between the thoughts reported by the two groups during the entire session, and no differences between groups during the three separate tasks (baseline, thinking about their speech, and the speaking tasks). Possible explanations and suggestions for research are discussed.

Role of cellulosic and noncellulosic membranes in hyperhomocysteinemia and oxidative stress.

Hyperhomocysteinemia is an independent risk factor for cardiovascular morbidity and mortality in end-stage renal disease (ESRD) with an increased relative risk (RR) of 1% per micromol/L in total homocysteine concentration. In ESRD patients who undergo hemodialysis (HD), the antioxidant system is largely inadequate in correcting the imbalance between generation and scavenging of reactive oxygen species (ROS). To clarify the role of several cellulosic (CMs) and noncellulosic of synthetic membranes (NCMs) upon hyperhomocysteinemia and the oxidative stress, we measured plasma (P) homocysteine (t-HCY), plasma lipid peroxidation (LPO), and erythrocyte (E) concentration of several antioxidant enzymes in 20 normal subjects, in 35 HD patients treated with CMs, and in 29 patients treated with NCMs. Before, during, and after the first session of the week (at times 0', 120', end, 30' after HD end), blood samples were drawn. Plasma (P) homocysteine (t-HCY), cysteine (CYS), malondialdehyde (MDA), erythrocyte (E)-glutathione (GSH), glucose-6-phosphodehydrogenase (G6PD), glutathione reductase (GR), glutathione peroxidase (GPx), catalase (CAT), and superoxide-dismutase (SOD) were determined. The dialytic procedure significantly decreased the three plasma parameters, but none normalized (as a mean). The E-enzymes scavenging ROS (lower than normal before session) increased throughout the session, but the normal range of activity was never reached. Different membranes have shown different effects. When these effects on P and E spaces were pooled, we were able to classify the membranes as follows. In a general sense, cellulosic membranes are less effective than synthetic membranes both on lipoperoxides (LPO) and antioxidant activity (AOA). Among synthetic membranes, PMMA is the best membrane both for plasma values and lesser enzymatic derangement during the session. A practical system for classifying the anti-atherosclerotic action and antioxidant activity of dialytic membranes is proposed.

Dialysis kinetics of homocysteine and reactive oxygen species.

In patients with chronic renal failure who undergo hemodialysis (HD), the antioxidant system is inadequate to correct the imbalance between the generation and scavenging of reactive oxygen species. To clarify the role of six different membranes on oxidative stress, the authors measured plasma lipid peroxidation and erythrocyte (E) concentrations of several antioxidant enzymes in 30 HD patients: 20 on bicarbonate HD, 4 on paired filtration dialysis, 3 on acetate free biofiltration, and 3 on hemodiafiltration. Before, during, and after the first session of the week (at times 0, 30, 60, and 120 min, end, and 30 min after end of HD), several blood samples were drawn. Plasma (P) homocysteine (HCY), cysteine (CYS), malondialdehyde (MDA), E-glutathione (GSH), glucose-6-phosphodehydrogenase, glutathione reductase (GR), glutathione peroxidase (GP), catalase (CAT), and superoxide dismutase (SOD) were determined. All six membranes (Hemophan [HEMO]; cellulose diacetate [DIAC]; acrylonitrile-69 [AN69]; polymethylmethacrylate [PMMA]; cuprammonium rayon [CURAY]; polysulfone plus hemophan [PS + HEMO]) induced a significant decrease in plasma lipid peroxidation (p < 0.001) and an increase in E-GSH, GR, GR + flavinadenine dinucleotide, GP, and SOD (p < 0.001). Some membranes, however, showed some peculiar effects on reactive oxygen species: HEMO is better than DIAC, as far as P-MDA and P-HCY are concerned; PMMA induces higher changes in E-GR and P-CYS than does HEMO; and patients chronically using PMMA and PS + HEMO membranes show the lowest P-HCY levels both before and after dialytic sessions. Based on these changes, implications as to the effects on vascular disorders could be derived.

Listener ratings of the intelligibility of tracheoesophageal speech in noise.

The purpose of this investigation was to determine the extent to which listener ratings of the intelligibility of tracheoesophageal puncture (TEP) speech vary as a function of different signal-to-noise ratios. Fifty college students, 25 men and 25 women (Median age = 19.7 years) participated in the study. They were instructed to assign numbers to audio-recorded speech samples in each of nine signal-to-noise ratio conditions (+65 dB, +20 dB, +15 dB, +10 dB, +5 dB, 0 dB, -5 dB, -10 dB, and -15 dB) in two separate magnitude estimation scaling tasks. During Task 1 the subjects rated the intelligibility of a TEP speech sample. In Task 2 the subjects rated the intelligibility of a normal speech sample. The results indicated that as the levels of background noise increased, listener ratings of intelligibility decreased (F 8,392 = 37.84; p < or = .0001).

Factors related to magnitude estimation scaling of complex auditory stimuli: aging.

The purpose of this study was to examine the effects of aging on magnitude estimation scaling of the loudness of complex auditory stimuli in the form of rock music. The subjects were 10 young adults (M age = 19.3 yr.), and 10 older individuals (M age = 54.2 yr.). The older individuals' mean numerical responses suggested that they perceived the rock music stimuli as louder for all nine suprathreshold intensities tested. The older group of subjects may have perceived the suprathreshold stimulus intensities as being louder because of physical and affective changes that naturally occur in central auditory processing during the aging process.

Magnitude estimation scaling of the loudness of a wide range of auditory stimuli.

The study of the perception of loudness lends itself well to the psychophysical scaling technique of magnitude estimation. This study was designed to extend the range of auditory stimuli used to study the magnitude estimation scaling of loudness. The five stimuli chosen were a 1000-Hz pure tone, narrow band noise (700-1300 Hz band width), broad band noise (100-10,000 Hz band width), rock music, and babble speech, i.e., speech in which meaning is not discernible because several individuals are talking at once. Subjects were 30 normal young women (M = 19 yr.). During the auditory magnitude-estimation task for each of the five stimuli, a subject was instructed to assign numbers to stimulus presented in a randomly ordered series of nine sensation levels (10, 20, 30, 40, 50, 60, 70, 80, and 90 dB SL). Multivariate analysis of variance for repeated measures indicated there were no significant differences in the numerical responses of the subjects for the five stimuli. A possible explanation for these results is the presence of an underlying stabilizing factor (internal scaling mechanism) that allows adults to scale loudness consistently irrespective of the type of auditory stimulus.

Free radicals and oxidative stress challenge dialysis patients: effects of two different membranes.

Patients with end-stage renal disease (ESRD) who undergo hemodialysis manifest pronounced oxidative stress (OS), for the antioxidant system is inadequate to correct the imbalance between generation and scavenging of reactive oxygen species (ROS). To clarify the role of two different membranes on the OS, we measured plasma lipid peroxidation (LPO) and erythrocyte concentration of several antioxidant enzymes on 20 controls and 6 patients on bicarbonate dialysis (BHD). At 7 days intervals, 2 BHD sessions were done on the same 6 hemodialysis patients: the two BHD sessions were similar, except for the membrane used (cuprophan, first study; regenerated cellulose = Bioflux, second study, 7 days later). Before, during, and after each session (0', 30', 60', 120', end, 30' after BHD end), several blood samples were drawn. Lipid peroxidation and erythrocyte glutathione (GSH), superoxide dismutase (SOD), and catalase were spectrophotometrically determined (Bioxytech, France), but for erythrocyte glutathione peroxidase (Gpx) and G-6-PD, Gunzler's and Beutler's methods were used, respectively. Both membranes induce a significant decrease in LPO (p < 0.01) and an increase in erythrocyte SOD (p < 0.05). Bioflux shows some peculiar effects: a significant increase in erythrocyte GSH (p < 0.05) and erythrocyte catalase (p < 0.01) with a gradual increase of erythrocyte SOD and catalase/SOD ratio. Cuprophan, on the contrary, causes a sudden increase in erythrocyte SOD, while erythrocyte catalase decreases. These data support the view that Bioflux induces an OS lower than cuprophan because with the former, increased H2O2 production leads (thanks to catalase and GPx action) to water generation. With cuprophan, instead the reduced SOD/catalase ratio causes a greater H2O2 generation and a lower conversion to water.

Magnitude estimation scaling of annoyance in response to rock music: effects of sex and listeners' preference.

The present study parallels an earlier one Fucci, Petrosino, and Banks in 1994 concerned with sex and listeners' preference effects on magnitude estimation scaling of rock music. The difference between the two studies is that the subjects in 1994 were asked to scale "loudness" while the present subjects were asked to scale "annoyance." The prior results and those of the present study were different, i.e., the women's preference appeared influential in the magnitude estimation scaling of rock music previously but here the men's preference appeared influential. If subjects are instructed to judge the annoyance of an auditory signal, they may respond differently than if asked to judge its loudness. Judgments of annoyance appear to be more context dependent whereas loudness judgments may reflect a perceptual process more closely related to physical aspects of the signal.

The effect of preference for three different types of music on magnitude estimation-scaling behavior in young adults.

The purpose of the present study was to assess the effect of preference for three different types of music on magnitude estimation scaling behavior in young adults. Three groups of college students, 10 who liked rock music, 10 who liked big band music, and 10 who liked classical music were tested. Subjects were instructed to assign numerical values to a random series of nine suprathreshold intensity levels of 10-sec, samples of rock music, big band music, and classical music. Analysis indicated that subjects who liked rock music scaled that stimulus differently from those subjects who liked big band and classical music. Subjects who liked big band music scaled that stimulus differently from those subjects who liked rock music and classical music. All subjects scaled classical music similarly regardless of their musical preferences. Results are discussed in reference to the literature concerned with personality and preference as well as spectrographic analyses of the three different types of music used in this study.

Linguistic aspects of magnitude-estimation scaling of instrumental music, instrumental music with vocal accompaniment, and spoken lyrics.

An analysis of variance of magnitude estimates of loudness of three different types of complex auditory stimuli, instrumental music, instrumental music with vocal accompaniment, and spoken lyrics showed, for 100 young adults, no differences for the types of stimuli. The linguistic aspects of these complex auditory stimuli do not differentially influence loudness judgments.

Age-related differences in acoustical aspects of contrastive stress in women.

The purpose of this investigation was to compare the fundamental frequency (F0), durational, and sound pressure characteristics of speech during production of contrastive stress, a suprasegmental component of speech, in young adult and elderly women. Results indicate that, while both groups significantly increased F0, duration, and sound pressure level during production of contrastive stress, elderly women increased F0 to a significantly greater extent than young women and, for all acoustic parameters, the groups were dissimilar in position effects. In spite of the age related differences, such differences did not appear to limit the ability of elderly women to provide linguistic information through prosody. However, they may do so differently from young women. These findings may have implications in terms of treatment of speech disorders in the elderly.

Oral vibrotactile assessment procedures: modifications.

An ongoing process to develop oral vibrotactile instrumentation that can be standardized and used in practical assessment of the oral tactile sensory system was reported in The International Journal of Orofacial Myology in March, 1990, by Fucci, Petrosino, and Harris. The material presented in the present article reflects the current research and future direction that the development of this instrumentation is taking. Potential benefits of this instrumentation for individuals working in the area of orofacial myofunctional disorders are suggested.

Language familiarity in magnitude-estimation scaling of loudness by young adults.

The purpose was to examine the effect of language familiarity on magnitude-estimation scaling of loudness by young adults. Two groups of subjects participated in this study. Group 1 of 20 subjects (M age = 23.95 yr.) were familiar with English and not familiar with Hindi. Group 2 of 20 subjects (M age = 24.30 yr.) were familiar with English as well as Hindi. Two separate magnitude-estimation scaling tasks were performed. On the first scaling task, an English sentence was used as the stimulus, and on the second scaling task, a Hindi sentence was used as the stimulus. Statistical analysis showed that there was no significant difference between the two groups in loudness judgments of the English and Hindi sentences. Subjects scaled the loudness of an unfamiliar language in the same manner as they scaled the loudness of a familiar language. The findings suggest that magnitude-estimation scaling is an effective measure of loudness whether the language being listened to is familiar to the listener.

The plasma glutathione peroxidase enzyme in hemodialyzed subjects.

The kidney is probably the major site of production of the plasma enzyme glutathione peroxidase (GSHPx-P). For this study, GSHPx-P activity was determined in 40 healthy people, in 34 patients with differing degrees of renal impairment, and in hemodialysis patients from whom blood samples were withdrawn either before or after each session (18 patients) or throughout the dialysis session (27 patients). Hemodialysis patients were treated by means of different techniques (bicarbonate hemodialysis, hemodiafiltration, and acetate free biofiltration), and different membranes (cuprophane, polyacrylonitrite, and polymethylmethacrylate). The following results were obtained: 1) GSHPx-P activity was significantly decreased in renal impairment patients; 2) GSHPx-P activity negatively correlated with serum creatinine values in renal impairment patients (r = -0.55; p < 0.001); and 3) the enzyme activity slightly increased after the session in hemodialysis patients. The following conclusions can be drawn: GSHPx-P activity could be new index of renal function, because it was decreased in patients with renal failure; the decrease in GSHPx-P activity paralleled the severity of renal impairment, and was maximal in hemodialysis patients; GSHPx-P activity was slightly raised at the end of the hemodialysis session, concomitant with other enzyme activities (aspartate transaminase, alanine transaminase, and alkaline phosphatase) and total protein concentration. This seems to be attributable to the process of water loss rather than other hypothetical mechanisms, such as A) enzyme activation by either peroxide generation during blood-membrane contact, or by the removal of a hypothetical inhibitor; and B) de novo synthesis in the residual renal mass or in other sites of production.

Effect of personality on magnitude-estimation scaling of complex auditory stimuli.

The purpose of the present study was to examine the effect of the personality trait of extraversion/introversion on magnitude-estimation scaling of complex auditory stimuli. Two groups of subjects, 10 who liked rock music (M age = 22.4 yr.) and 10 who disliked rock music (M age = 21.9 yr.), were tested. Subjects were instructed to assign numerical values to a random series of nine suprathreshold intensity levels of a 10-sec. sample of rock music. Each subject was given the Eysenck Personality Inventory, a test designed to measure the personality trait of extraversion/introversion. Statistical analyses indicated that the personality trait of extraversion/introversion did not appear to have an effect on the way the subjects scaled the rock-music stimulus.

Lingual vibrotactile magnitude-estimation scaling using a limited set of suprathreshold stimulus intensities.

The purpose of the present study was to assess feasibility of lingual vibrotactile suprathreshold testing with a limited number of intensities. 25 subjects ranging in age from 18 to 26 years (M = 19 yr.) participated. Two magnitude-estimation scaling tasks were presented to each subject with 1 wk. between tasks. One magnitude-estimation task involved eight suprathreshold intensities and the other involved four. Statistical analyses showed that there was no difference in subjects' responses to the two scaling efforts. In pure research endeavors it might make sense to continue to obtain as many magnitude-scaling data points as possible, but practical prudence may dictate a limited set of suprathreshold intensities for efficiency and subjects' comfort.

Effects of gender and listeners' preference on magnitude-estimation scaling of rock music.

The purpose of the present study was to examine the effects of gender and listener preference on magnitude-estimation scaling of rock music. Four groups of young adults were tested: 14 women who liked rock music, 14 women who disliked rock music, 14 men who liked rock music, and 14 men who disliked rock music. Subjects were instructed to assign numerical values to a random series of nine suprathreshold intensity levels of a 10-sec. sample of rock music. Analysis indicated that there was no difference in scaling performance between women and men. There was a difference in scaling performance between the group of women who liked rock music and the group of women who disliked rock music. There was no difference in the way the two groups of men performed the scaling task. These results suggest that men and women perform magnitude-estimation scaling of rock music similarly. Women, however, allow preference to influence how they choose numbers during magnitude-estimation scaling tasks whereas men do not.