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PubMed1985

Categorical perception of speech sounds via the tactile mode.

The usefulness of tactile devices as aids to lipreading has been established. However, maximum usefulness in reducing the ambiguity of lipreading cues and/or use of tactile devices as a substitute for audition may be dependent on phonemic recognition via tactile signals alone. In the present study, a categorical perception paradigm was used to evaluate tactile perception of speech sounds in comparison to auditory perception. The results show that speech signals delivered by tactile stimulation can be categorically perceived on a voice-onset time (VOT) continuum. The boundary for the voiced-voiceless distinction falls at longer VOTs for tactile than for auditory perception. It is concluded that the procedure is useful for determining characteristics of tactile perception and for prosthesis evaluation.

Adult↗

PubMed1991

Following up on treated stutterers: studies of perceptions of fluency and job status.

The present research aimed to investigate perceptions of fluency of persons treated with a fluency shaping technique called smooth speech. Four separate studies were conducted. The first showed that virtually all those treated were satisfied with their fluency following treatment. However, this satisfaction decreased to under half in the long term. The second study showed considerable opportunity in the long term for job promotion and upgrade in occupation for persons successfully completing a smooth-speech program. The third study compared employer perceptions of their employees' speech between a group who had received treatment for stuttering and a nontreatment control. The employers' perceptions of the treatment group were significantly enhanced, whereas no significant change occurred in employers' perceptions for the control group. The last study explored possible determinants of relapse in a population of treated stutterers. Results showed that most had experienced some degree of relapse, but had subsequently recovered. Few believed their relapse was associated with being embarrassed about using smooth speech. The majority believed their relapses were related to feeling pressured to speak faster. Investigating perceptions of fluency following treatment for stuttering seems an important goal for research in order to enhance treatment effectiveness. Directions for further research into this area are discussed.

Adult↗

PubMed1999

Alcoholic beverage choice, risk perception and self-reported drunk driving: effects of measurement on risk analysis.

AIMS: The present study examined effects of measurement on risk curve analysis in an application involving prediction of frequency and indicator measures of drunk driving with beverage-specific alcohol consumption and risk perception measures. DESIGN AND PARTICIPANTS: From a 1995 in-person survey of the US adult household population (response rate = 77%) the responses of 1260 adult drivers who reported any drinking in the prior year were selected for analysis. Regression and graphical techniques were used to investigate relationships between drinking pattern, beverage choice, perception of risks of drinking before driving, and frequency of drunk driving. MEASUREMENTS: Self-reported drunk driving (occurrence) was measured by a question assessing driving after drinking enough to be in trouble if stopped by the police within the prior 12 months; those affirming this (n = 191) were asked how many times they did so (frequency). Alcohol consumption was assessed by beverage and in combination. Risk perception was assessed as a factor score from three correlated measures. Demographic variables included age, ethnicity, education and income. FINDINGS: Controlling for demographics, heavy beer consumption (p < 0.01) more than heavy wine (NS) or liquor/spirits (p < 0.05) intake was strongly predictive of risk perception. A regression analysis showed a significant interaction between heavy beer consumption and perceived risk (p < 0.001) in predicting reported frequency of drunk driving, after controlling for heavy beer consumption (p < 0.05), total alcohol consumption and risk perception (both ps < 0.001). No interactions were important in equivalent models predicting dichotomous occurrence. Graphic analysis showed the shape of the risk curve is altered when frequency of drunk driving is taken into account rather than simple occurrence. CONCLUSIONS: Individuals' underestimation of beer's intoxicating effects, compared to other alcoholic beverage types, helps explain beer's over-representation in drinking driving violation reports. There is a need for creative public health campaigns designed to inform young men of beer's alcohol content and associated risks.

Adult↗

PubMed2000

The perception of dyspnoea in patients with asthma, before and following treatment with inhaled glucocorticosteroids.

This study was designed in order to establish the perception of breathlessness during rest and while breathing against resistance, in patients with asthma, before and after 8 weeks of inhaled glucocorticoids (IGC) treatment and to compare these parameters in patients with and without improvement in FEV1. Sixty-seven asthmatic patients, with moderate asthma, attending the asthma clinic, and 20 normal subjects were studied. After a 2-week run-in period, in which the subjects were asked to use exclusively beta2-agonists as needed, the asthmatic patients were randomized to receive either treatment with IGC, 250 microg of fluticasone propionate (FP) twice a day, via a diskhaler (47 patients), or to receive placebo (20 patients) and to serve as a control group, for 8 weeks. Spirometry and measurements for the sensation of dyspnoea were performed before and at the end of the treatment period. The mean dyspnoea score during breathing against resistance was significantly lower (P<0.05) in the patients with asthma than in normal subjects, before entering the study. Following 8 weeks of inhaled FP, there was a significant improvement in the mean dyspnoea score during breathing against resistance in the asthmatics receiving IGCs but not in the control group (P<005). In the study group 32 patients had an improved FEV1 > 15% and 15 patients did not. There was a statistically significant difference in perception of dyspnoea (P<0.01), between the group of patients with a improved FEV1 and the group of patients that were under IGC treatment without improvement in their FEV1. There was also a difference in the mean beta2-agonists consumption between the two groups (P<0.01). Asthmatic patients have a significantly lower perception of dyspnoea compared to normal subjects. IGC treatment was associated with increased perception of dyspnoea. However, this improvement was noted only in patients with improved FEV1, while the patients without improvement remained with an equal degree of dyspnoea perception and beta2-agonists consumption.

Administration, Inhalation↗

PubMed2003

[Oropharyngeal vocal tract space during singing--comparison of tactile-kinesthetic and auditory perception with objective endoscopic findings].

BACKGROUND: In this study we compared the perceived diameter of the vocal tract's oropharyngeal part with the diameter that was determined endoscopically. METHODS: 28 singers (13 male, 15 female) were examined with transnasal fiberscopic pharyngoscopy while singing the vowels /a/, /i/ and /u/ in 4 different timbres (normal, opened, covered, dumpled) and 3 different pitches (chest/modal register, subjective comfortable pitch for singing, head/falsetto register). The tactile-kinesthetic and auditive rating of the singers, the auditive rating of a singing teacher and the visual-endoscopic analysis of three laryngologists were compared. RESULTS: The tactile-kinesthetic and auditory self-perception of the singers was quite different from the auditive perception of a singing teacher and visual endoscopic findings of the laryngologists. The singers had the impression that the different singing timbres (normal, opened, covered, dumpled) influence oropharyngeal vocal tract space during singing. They judged the vowel itself and the pitch as having very little influence. Based on his auditory perception, the singing teacher also rated that the timbre plays an important role for the oropharyngeal vocal tract space but he found vowels to be the parameter with the greatest impact. Via visual endoscopic examination we found that, among the three parameters (vowel, timbre, pitch), the different vowels are most influential on the oropharyngeal vocal tract space. Analysis of video sequences revealed that pitch and timbre are less important. CONCLUSION: Subjective tactile-kinesthetic and auditory perception of the singers differs from auditory perception of the singing teacher as well as from endoscopic findings. The endoscopically determined oropharyngeal vocal tract space during singing the vowels /i/ or /u/ tends to be larger compared to the oropharyngeal vocal tract space while singing the vowel /a/.

Adult↗

PubMedDate not supplied

[Are specific developmental language disorders caused by deficits in auditory perception?].

BACKGROUND: Specific language impairment is assumed to be caused by deficits in auditory perception and therefore the training of auditory abilities is recommended as a treatment. Our study focussed on the question of whether a correlation between language disorders and auditory perception abilities can be proven empirically. PATIENTS: 23 language impaired children and 52 controls aged 7 to 11 years were examined. METHOD: Auditory abilities were measured by means of a battery of nonverbal and verbal tests. The children had to identify tones of different frequencies, loudness, duration or patterns as well as every day sounds and mixtures of such sounds. Noise-overlaid, time-compressed and frequency-limited speech tasks, and binaural summation tasks were also used. In addition, phoneme discrimination ability and auditory memory were assessed. RESULTS: Language impaired children scored low on phoneme discrimination and auditory memory tests but not on nonverbal or verbal auditory perception tasks. There are significant correlations between their expressive language ability and their scores on phoneme discrimination, auditory memory and sound duration identification tests. CONCLUSIONS: The results do not support the assumption that developmental language disorders are associated with auditory perception deficits. However, there are indications that auditory memory and time processing are deficient. Thus, training of auditory perception does not appear to be a suitable treatment for language impaired children.

Audiometry, Pure-Tone↗

PubMed1991

Some observations on the perception of Marroquin patterns.

Demonstrations are presented to show that the perception of structure in Marroquin patterns is disrupted if the dots comprising the pattern have opposite contrast polarity, and also if the dots comprising the pattern are separated in stereoscopic depth. It is also demonstrated that the perception of structure in a Marroquin pattern is made possible if the pattern is separated in stereoscopic depth from 'noise' dots, where the pattern structure cannot be perceived in either half of the unfused stereogram. In these respects the perception of Marroquin patterns is similar to the perception of Glass patterns. These findings are thus consistent with the proposal that the perception both of Marroquin and of Glass patterns is based on the construction of virtual lines.

Attention↗

PubMed1995

Binocular perception of slant about oblique axes relative to a visual frame of reference.

From the literature it is known that the processing of disparity for slant is different in the presence and in the absence of a visual frame of reference. The experimental finding that vertical disparity is not processed for slant perception in the presence of a visual reference is elaborated. This theoretical analysis results in a reduction of the three basic first-order transformations between the retinal half images (divergence, rotation, and deformation) to only two basic orthogonal transformations. The first of these, horizontal scale, results in slant perception about the vertical axis, whereas the second, horizontal shear, results in slant perception about the horizontal axis. These transformations are based primarily on horizontal disparity. It is shown experimentally that in the presence of a frame of reference the amount of vertical transformation that is added to the two basic transformations (horizontal scale and shear) of a random-dot stimulus is indeed irrelevant for slant perception. It is suggested that, in the presence of a visual reference, slant perception about oblique axes is based solely on linear combinations of the horizontal-scale and horizontal-shear transformations. Subjects are able to reproduce slants about oblique axes experimentally merely by combining horizontal scale and shear.

Adult↗

PubMed2003

Prior knowledge about display inversion in biological motion perception.

Display inversion severely impedes veridical perception of point-light biological motion (Pavlova and Sokolov, 2000 Perception & Psychophysics 62 889-899; Sumi, 1984 Perception 13 283-286). Here, by using a spontaneous-recognition paradigm, we ask whether prior information about display orientation improves biological motion perception. Participants were shown a set of 180 degrees inverted point-light stimuli depicting a human walker and quadrupeds (dogs). In experiment 1, one group of observers was not aware of the orientation of stimuli, whereas the other group was told beforehand that stimuli will be presented upside down. In experiment 2, independent groups of participants informed about stimulus orientation saw the same set of stimuli, in each of which either a moving or a static background line was inserted. The findings indicate that information about display inversion is insufficient for reliable recognition of inverted point-light biological motion. Instead, prior information facilitates display recognition only when it is complemented by additional contextual elements. It appears that visual impressions from inverted point-light stimuli remain impenetrable with respect to one's knowledge about display orientation. The origins of orientation specificity in biological motion perception are discussed in relation to the recent neuroimaging data obtained with point-light stimuli and fragmented Mooney faces.

Adolescent↗

PubMed2005

Perception time measured with the slope-transition paradigm (STP): category, set size, and task manipulations.

A perception time measure was obtained with the 'slope-transition paradigm' (STP), which is described in detail. In two experiments with the paradigm, participants viewed two sequential data frames, each presented for a wide range of durations. They made a binary response based on combined information from the two frames. The results showed piecewise linear response-time versus frame-duration functions with a slope-0 branch at short durations, followed by a slope-1 branch. The duration where the two branches met (the slope transition) was interpreted as the end of the perception of frame 1. For longer durations, the participant had completed the perception of frame 1 and was forced to waste time waiting for data from frame 2. In experiment 1, an odd-digit enumeration task was used, and set size and distractor category (even digits versus consonants) were varied. In experiment 2, a same/different task with digits was used and the type of judgment (literal versus parity) was varied. Perception time increased with set size. Distractor category and judgment type affected post-perceptual processes. The perception time measure of the STP is considered in relation to the attentional blink, repetition blindness, and object files.

Choice Behavior↗

PubMed2002

Perception of biological motion without local image motion.

A vivid perception of the moving form of a human figure can be obtained from a few moving light points on the joints of the body. This is known as biological motion perception. It is commonly believed that the perception of biological motion rests on image motion signals. Curiously, however, some patients with lesions to motion processing areas of the dorsal stream are severely impaired in image motion perception but can easily perceive biological motion. Here we describe a biological motion stimulus based on a limited lifetime technique that tests the perception of a moving human figure in the absence of local image motion. We find that subjects can spontaneously recognize a moving human figure in displays without local image motion. Their performance is very similar to that for classic point-light displays. We also find that tasks involving the discrimination of walking direction or the coherence of a walking figure can be performed in the absence of image motion. Thus, although image motion may generally aid processes such as segmenting figure from background, we propose that it is not the basis for the precept of biological motion. Rather, we suggest biological motion is derived from dynamic form information on body posture evolving over time.

Humans↗

PubMed2001

What visual perception tells us about mind and brain.

Recent studies of visual perception have begun to reveal the connection between neuronal activity in the brain and conscious visual experience. Transcranial magnetic stimulation of the human occipital lobe disrupts the normal perception of objects in ways suggesting that important aspects of visual perception are based on activity in early visual cortical areas. Recordings made with microelectrodes in animals suggest that the perception of the lightness and depth of visual surfaces develops through computations performed across multiple brain areas. Activity in earlier areas is more tightly correlated with the physical properties of objects whereas neurons in later areas respond in a manner more similar to visual perception.

Brain↗

PubMed2004

Comparison of speech perception between monaural and binaural hearing in cochlear implant patients.

OBJECTIVE: To assess the advantages of binaural hearing for cochlear implant (CI) users using a hearing aid (HA) for the contralateral ear. MATERIAL AND METHODS: The subjects comprised 3 males and 3 females (age range 48-84 years). All of them had been using a CI and HA for > 6 months. Their speech perception was examined in quiet using monosyllables and Japanese Hearing in Noise Test (J-HINT) sentences. Speech perception in noise was examined using J-HINT sentences. Late cortical waves were measured while subjects listened to 1 kHz frequent and 2 kHz target tone stimuli. The latency of the event-related potential (P300) wave was compared for monaural and binaural hearing conditions. RESULTS: Three subjects showed significantly better results for binaural than monaural (CI alone) hearing for monosyllables and HINT sentences (p < 0.05; paired t-test). Subjects with better speech perception had been using an HA for longer than those with poor performance (18.3 vs 4.0 years). The overall average score was better for binaural than monaural hearing in the speech perception test under quiet and noisy conditions. Comparison of the latency of the P300 wave under monaural and binaural hearing conditions showed a significantly shorter latency for the latter (p = 0.02; paired t-test). CONCLUSIONS: Although the use of an HA alone showed marginal benefit for CI users, binaural hearing (CI+HA) resulted in a significant improvement in speech perception under various circumstances.

Aged↗

PubMed2005

Blink reflex and auditory speech perception in prelingually cochlear-implanted children.

CONCLUSION: The results of this study show that R- prelingually cochlear-implanted children are not optimal candidates for cochlear implantation. However, if this group are implanted, other rehabilitation methods should be incorporated into their rehabilitation program in order to achieve better results and maximize the efficacy of their prosthesis. OBJECTIVE: To demonstrate that the blink reflex or auropalpebral reflex evaluation can be used as a prognostic factor for the assessment of auditory and speech perception levels in prelingually cochlear-implanted children. MATERIAL AND METHODS: In an observational, analytical, prospective study conducted at a single cochlear implant rehabilitation center in 85 prelingually cochlear-implanted children, the presence or absence of the blink reflex (BR) was evaluated and the results of auditory and speech perception tests were compared between reflex-positive (R+) and reflex-negative (R-) patients. To obtain the BR, four electrodes were applied in both the Nucleus and MED-EL systems and then stimulated by means of current levels higher than the previously detected most comfortable level of the patient until the reflex appeared. Auditory and speech perception levels were measured using the vowels-confusion test and the categorization of auditory perception scale. RESULTS: The mean results of auditory and speech perception tests were significantly higher in R+ compared to R- patients.

Auditory Threshold↗

PubMedDate not supplied

Current perception thresholds in vibration-induced neuropathy.

The authors evaluated the usefulness of current perception threshold testing for the assessment of vibration-induced neuropathy. The study population comprised 20 male controls and 59 males with hand-arm vibration syndrome. Current perception threshold at three test frequencies (i.e., 5 Hz, 250 Hz, and 2,000 Hz) was determined on the distal phalanges of the index and little fingers. Large myelinated fibers, small myelinated fibers, and unmyelinated fibers were evaluated selectively at 2,000-Hz, 250-Hz, and 5-Hz frequencies, respectively. The vibration-induced neuropathy groups had significantly increased current perception thresholds in both the index and little fingers. There was a significant increase in current perception threshold for the myelinated fibers, but not the unmyelinated fibers. The diagnostic sensitivity for vibration-induced neuropathy was relatively high. It appeared that current perception threshold evaluation was useful for the assessment of vibration-induced neuropathy.

Aged↗

PubMed1980

Effects of a remedial program on visual-motor perception in spina bifida children.

Most studies dealing with spina bifida children concentrate on medical or physical factors, largely ignoring any psychosocial and educational consequences. The present study assessed the effect of a remedial program on visual-motor perception in spina bifida children. Thirty-six spina bifida boys and girls (mean age 82.87 months) with a myelomeningocele and an associated hydrocephalus were assigned randomly to either a control, attention-placebo, or experimental group. Following the administration of the Frostig Program for the Development of Visual Perception, the experimental group significantly improved on a global index of visual perception and the five subtests of Frostig's Development Test of Visual Perception; at a maintenance test two months later, all treatment gains (except on the visual spatial perception subtest) were still evident. These results are discussed in terms of the provision of remedial education for spina bifida children, and a possible cognitive mechanism mediating the behavioral change in the experimental group.

Child↗

PubMed2001

Effects of nonverbal behavior on perceptions of a female employee's power bases.

The authors extended a previous examination of the effects of nonverbal behavior on perceptions of a male employee's power bases (H. Aguinis, M. M. Simonsen, & C. A. Pierce, 1998) by examining the effects of nonverbal behavior on perceptions of a female employee's power bases. U.S. undergraduates read vignettes describing a female employee engaging in 3 types of nonverbal behavior (i.e., eye contact, facial expression, body posture) and rated their perceptions of the woman's power bases (i.e., reward, coercive, legitimate, referent, expert, credibility). As predicted, (a) direct eye contact increased perceptions of coercive power, and (b) a relaxed facial expression decreased perceptions of all 6 power bases. Also as predicted, the present results differed markedly from those of Aguinis et al. (1998) regarding a male employee. The authors discuss implications for theory, future research, and the advancement of female employees.

Adolescent↗

PubMed1988

Correspondence between perceptions of change in diet and 15-year change in diet reports in the Tecumseh Diet Methodology Study.

As part of an effort to assess the most reliable method of obtaining information about long-term dietary intake, a study was conducted of the correspondence between perception of change in diet and measured change in reported diet from 1967 to 1982. Respondents were 1,201 men and women participants in the Tecumseh Food Frequency Study of 1967-1969 who were 45-64 years of age in 1982-1983, the time of the Diet Methodology Study. Perceptions of change were obtained by asking respondents directly if they thought they currently ate each of 12 food groups more often, less often, or as often as they did during the year of their earlier interview. Measured change was obtained by subtracting each respondent's baseline frequency for each of the 12 food groups from his or her current frequency. For 10 of the 12 food groups, correspondence was found between perception of change and measured change; fats and oils added at the table and meat were the exceptions. Significant linear relationships were found between perceptions and measured change for all food groups except fats and oils. However, greatly varying coefficients were associated with terms such as more often or as often as before, thereby limiting the potential utility of combining perceptions of change with current frequencies to obtain a reliable measure of baseline frequencies.

Data Collection↗