Paired-comparison Paradigm Research Articles

Chamber music hall acoustics: Measurements and perceptual differences.

This study investigates the room acoustics of seven chamber music halls of various modern and historical architecture by means of objective room acoustic measures and a subjective listening experiment. The acoustic measurements were performed with heavy cloth covering the audience areas to simulate occupancy in the halls. A loudspeaker quartet was used for auralizations, which were reproduced in a surrounding loudspeaker array. The perceptual differences between the halls were evaluated in terms of envelopment, warmth, clarity, proximity, and preference by using a paired comparison paradigm. The subjective evaluations were conducted in two different laboratories and latent class analysis was used to study the agreement between laboratories and the emergence of different listener groups in the ratings of each attribute. Concerning preference, the emergence of two groups found in the study of large symphony halls was confirmed, where one group prefers rich, enveloping sound and one group prefers high clarity. The perceptual ratings were not clearly associated with a specific hall shape, but rather depended on the distribution of early and late sound energy. Thus, the distinction between rectangular and non-rectangular floor plans previously found for large symphony halls was not observed with these smaller halls.

The discrimination of expressions in facial movements by infants: A study with point-light displays

Perceiving facial expressions is an essential ability for infants. Although previous studies indicated that infants could perceive emotion from expressive facial movements, the developmental change of this ability remains largely unknown. To exclusively examine infants’ processing of facial movements, we used point-light displays (PLDs) to present emotionally expressive facial movements. Specifically, we used a habituation and visual paired comparison (VPC) paradigm to investigate whether 3-, 6-, and 9-month-olds could discriminate between happy and fear PLDs after being habituated with a happy PLD (happy-habituation condition) or a fear PLD (fear-habituation condition). The 3-month-olds discriminated between the happy and fear PLDs in both the happy- and fear-habituation conditions. The 6- and 9-month-olds showed discrimination only in the happy-habituation condition but not in the fear-habituation condition. These results indicated a developmental change in processing expressive facial movements. Younger infants tended to process low-level motion signals regardless of the depicted emotions, and older infants tended to process expressions, which emerged in familiar facial expressions (e.g., happy). Additional analyses of individual difference and eye movement patterns supported this conclusion. In Experiment 2, we concluded that the findings of Experiment 1 were not due to a spontaneous preference for fear PLDs. Using inverted PLDs, Experiment 3 further suggested that 3-month-olds have already perceived PLDs as face-like stimuli.

Preferred Strength of Noise Reduction for Normally Hearing and Hearing-Impaired Listeners.

Preference for noise reduction (NR) strength differs between individuals. The purpose of this study was (1) to investigate whether hearing loss influences this preference, (2) to find the number of distinct settings required to classify participants in similar groups based on their preference for NR strength, and (3) to estimate the number of paired comparisons needed to predict to which preference group a participant belongs. A paired comparison paradigm was used in which participants listened to pairs of speech-in-noise stimuli processed by NR with 10 different strength settings. Participants indicated their preferred sound sample. The 30 participants were divided into three groups according to hearing status (normal hearing, mild hearing loss, and moderate hearing loss). The results showed that (1) participants with moderate hearing loss preferred stronger NR than participants with normal hearing; (2) cluster analysis based solely on the preference for NR strength showed that the data could be described well by dividing the participants into three preference clusters; (3) the appropriate cluster membership could be found with 15 paired comparisons. We conclude that on average, a higher hearing loss is related to a preference for stronger NR, at least for our NR algorithm and our participants. The results show that it might be possible to use a limited set of pre-set NR strengths that can be chosen clinically. For our NR one might use three settings: no NR, intermediate NR, and strong NR. Paired comparisons might be used to find the optimal one of the three settings.

Use of Emotional and Neutral Speech in Evaluating Compression Speeds.

Emotional speech differs from neutral speech in its envelope characteristics. Use of emotional speech materials may be more sensitive for evaluating signal processing algorithms that affect the temporal envelope. Subjective listener preference was compared between variable speed compression (VSC) and fast acting compression (FAC) amplitude compression algorithms using neutral and emotional speech. The study used a single-blinded, repeated measures design. Twenty hearing-impaired (HI) listeners with a bilaterally symmetrical, mild- to-moderately severe sensorineural hearing loss and 21 listeners with normal hearing (NH) participated. Speech was processed using FAC and VSC algorithms. A paired-comparison paradigm assessed subjective preference for FAC versus VSC using emotional and neutral speech materials. The significance of subjective preference for compression algorithm (FAC or VSC) was evaluated using a linear mixed effects model at each combination of stimulus type (emotional or neutral speech) and hearing group (NH or HI). HI listeners showed a preference for VSC over FAC when listening to emotional speech. The same listeners showed a nonsignificant, preference for VSC over FAC when listening to neutral speech. NH listeners showed preference for VSC over FAC for both neutral and emotional speech materials. These results suggest that the subjective sound quality of emotional speech is more susceptible than neutral speech to changes in the signal introduced by FAC. Clinicians should consider including emotional speech materials when evaluating listener preference for different compression speeds in the clinic.

How Reliable Is the Auditory-Perceptual Evaluation of Phonation Onset Hardness?

Generally, phonation onset hardness has been similarly defined and categorized throughout literature. There are typically three categories: soft, breathy, and hard onset. Phonation onset hardness is relevant in both assessment and treatment of various voice disorders and is usually determined on an auditory-perceptual basis. However, as far as we know, reliability of clinical auditory-perceptual indications of phonation onset hardness has not been investigated yet. Therefore, this study aimed at evaluating intrarater as well as interrater reliability of auditory-perceptual assessment of phonation onset hardness by speech and language pathologists. After deidentification, the sentence-initial word [e.rst] was extracted from read text recordings of 20 subjects with various voice disorders and complaints. These 20 samples were purposefully selected to represent as much as possible the whole phonation onset hardness continuum. The auditory-perceptual rating protocol consisted of the paired comparison paradigm, in which all listeners were asked to perceptually compare phonation onset hardness of every fragment with the other 19 samples. This resulted in a ranking of the 20 samples, from hardest to softest phonation onset. Four speech and language pathologists agreed to compare phonation onset hardness according to this paradigm. The single-measures intraclass correlation coefficient (ICC) for absolute agreement was applied to determine the degree of reliability within as well as between raters. Intrarater ICC's showed acceptable reliability for two raters, yet poor reliability for the other two raters. Interrater ICC's demonstrated low reliability in general. Zooming in on the ratings shows that three of four evaluators agreed on which sample had the softest phonation onset, and that only two raters agreed on which recording had the hardest phonation onset. It can be concluded that there is considerable variability within and across raters when asked to indicate the word with the hardest phonation onset. This is the first study to approach auditory interpretation of phonation onset hardness with the paired comparison task. Questions are raised about the clinical utility of phonation onset hardness perception, the potential role of training, and the importance of a more objective yet clinically feasible measurement tool.

Meaningful Memory? Eighteen-Month-Olds Only Remember Cartoons With a Meaningful Storyline.

In two studies we investigated the importance of a storyline for remembering cartoons across a delay of 2 weeks in 18-month-old infants by means of the visual paired-comparison (VPC) paradigm. In Study 1 seventy-one 18-month-olds were tested using similar cartoons as in a recent study from our lab while varying the richness of the storyline information. In a VPC task half of the infants watched uncompromised versions of the cartoons used in the recent study (Storyline Condition), whereas the other half watched Pixelized versions of the cartoons (number of pixels reduced by 98% covering up the narrative, but leaving perceptual details, e.g., colors, movements, the same, and Pixelized Condition). Two weeks later they were presented with the familiar cartoon and a novel cartoon from the same version (Storyline or Pixelized) simultaneously, while being eye-tracked. Results showed that only the infants in the Storyline Condition remembered the target cartoon, thus suggesting that the storyline is important for memory. However, an alternative interpretation of the results could be that what made the infants in the Storyline Condition remember the target cartoon was not the storyline, but the static conceptual information of the objects and agents present in the cartoon (which was not visible in the Pixelized version). To test this possibility, a control study was created. In Study 2 thirty-six infants were therefore presented with a version of the cartoon in which we broke down the temporal presentation into 1 s segments and presented these out of order. This was done to preserve the static conceptual information (e.g., objects and agents) while still disturbing the storyline. Results showed that the infants in this condition still did not remember the target cartoon, suggesting that the meaningfulness of the storyline – and not only static conceptual information – is important for later memory.

Effects of the tempo of background music on prospective and retrospective duration of a video program

To improve understanding of the effects of music on perception of video productions, subjective duration of a video program was measured in the paired-comparison paradigm using a 10-s video program selected from a 70-s daily news program mixed with a 90 beats-per-minute (bpm) music as a reference. Seven video programs were used for comparison, with actual durations ranging from 8.5 s to 11.5 s in steps of 0.5 s. These programs were selected randomly from the same video program and mixed with music played at 50, 90, and 140 bpm. Seven participants listened to a pair of video programs and then answered which program of the two was subjectively longer. The psychometric functions of retrospective perception of duration showed that video programs mixed with the fast-tempo music were perceived as short. In addition, five other participants were asked to prospectively produce a 10-s interval on a stopwatch while watching the same video programs. The actual times recorded generally exceeded 10 s, and were significantly long for the program mixed with slow-tempo music. The conflict between the results obtained from the two experiments on subjective duration and its relation to the fixed physical duration is discussed in terms of internal clocks.

Contributions of Look Duration and Gaze Shift Patterns to Infants' Novelty Preferences.

Data from 72 infants, tested using a serial paired-comparison paradigm, were analyzed to better understand infant novelty preferences. Infants between the ages of 15 and 26weeks were tested in three studies with familiar stimuli displayed adjacent to novel stimuli on each trial. Differences in look duration, look number, and gaze shifts directed at novel versus familiar stimuli were assessed to measure their contributions to group and individual novelty preferences. Infants produced longer looks for novel stimuli in all three studies, and stimulus differences in look duration accounted for more than 50% of the variability in individual novelty preferences. Infants that produced more looks to novel rather than familiar stimuli did not produce overall novelty preferences unless they also looked longer at novel stimuli. Gaze shift patterns did not predict individual novelty preferences, and novel stimuli did not determine where infants looked. The infants' visual exploration was constrained by memories for the direction of the previous look as well as by the attention-holding features of novel stimuli.

Perceptual and Acoustic Analyses of Good Voice Quality in Male Radio Performers

Good voice quality is an asset to professional voice users, including radio performers. We examined whether (1) voices could be reliably categorized as good for the radio and (2) these categories could be predicted using acoustic measures. Male radio performers (n = 24) and age-matched male controls performed "The Rainbow Passage" as if presenting on the radio. Voice samples were rated using a three-stage paired-comparison paradigm by 51 naive listeners and perceptual categories were identified (Study 1), and then analyzed for fundamental frequency, long-term average spectrum, cepstral peak prominence, and pause or spoken-phrase duration (Study 2). Study 1: Good inter-judge reliability was found for perceptual judgments of the best 15 voices (good for radio category, 14/15 = radio performers), but agreement on the remaining 33 voices (unranked category) was poor. Study 2: Discriminant function analyses showed that the SD standard deviation of sounded portion duration, equivalent sound level, and smoothed cepstral peak prominence predicted membership of categories with moderate accuracy (R2 = 0.328). Radio performers are heterogeneous for voice quality; good voice quality was judged reliably in only 14 out of 24 radio performers. Current acoustic analyses detected some of the relevant signal properties that were salient in these judgments. More refined perceptual analysis and the use of other perceptual methods might provide more information on the complex nature of judging good voices.

Acoustic Properties of the Voice Source and the Vocal Tract: Are They Perceptually Independent?

This study sought to determine whether the properties of the voice source and vocal tract are perceptually independent. Within-subjects design. This study employed a paired-comparison paradigm where listeners heard synthetic voices and rated them as same or different using a visual analog scale. Stimuli were synthesized using three different source slopes and two different formant patterns (mezzo-soprano and soprano) on the vowel /a/ at four pitches: A3, C4, B4, and F5. Whereas formant pattern was the strongest effect, difference in source slope also affected perceived quality difference. Source slope and formant pattern were not independently perceived. These results suggest that when judging laryngeal adduction using perceptual information, judgments may not be accurate when the stimuli are of differing formant patterns.

Objective Evaluation of Otoscopy Skills Among Family and Community Medicine, Pediatric, and Otolaryngology Residents

The objective of this study is to evaluate and compare the perceived need for otolaryngology training and otoscopy diagnostic skills in primary care (Family and Community Medicine, Pediatric Medicine), and Otolaryngology Head and Neck Surgery (OTO-HNS) postgraduate trainees. Participant otoscopy skills were evaluated using the OtoSim simulator. Family and Community Medicine, Pediatric, and OTO-HNS residents were recruited. Each resident participated in 3 separate otoscopy training and assessment sessions. The ability to correctly identify middle ear pathology was objectively evaluated using OtoSim™. Pretest, posttest, and 3-month retention test results were compared among residents in a paired comparison paradigm. Survey data assessing exposure to OTO-HNS during undergraduate and postgraduate training were also collected. A total of 57 residents participated in the study. All residents reported limited exposure to OTO-HNS during undergraduate medical training. Primary care trainees performed poorly on pretest assessments (30% ± 7.8%; 95% CI). Significant improvement in diagnostic accuracy was demonstrated following a single 1-hour teaching session (30%-62%; p < 0.001). Primary care residents demonstrated a significant decrease in diagnostic accuracy at a 3-month follow-up assessment (62%-52%, p < 0.001). Self-perceived comfort with otology was poorly correlated to pretest performance among primary care trainees (r = 0.26) and showed a stronger positive correlation among OTO-HNS trainees (r = 0.56). A single teaching session with an otoscopy simulator significantly improved diagnostic accuracy in primary care and OTO-HNS trainees. Improved performance is susceptible to deterioration at 3 months if acquired skills are not frequently used. Self-perceived comfort with otology may not be an accurate predictor of otoscopic diagnostic skill.

Evidence that Viewers Prefer Higher Frame-Rate Film

High frame-rate (HFR) movie-making refers to the capture and projection of movies at frame rates several times higher than the traditional 24 frames per second. This higher frame rate theoretically improves the quality of motion portrayed in movies, and helps avoid motion blur, judder, and other undesirable artifacts. However, there is considerable debate in the cinema industry regarding the acceptance of HFR content given anecdotal reports of hyper-realistic imagery that reveals too much set and costume detail. Despite the potential theoretical advantages, there has been little empirical investigation of the impact of high frame-rate techniques on the viewer experience. In this study, we use stereoscopic 3D content, filmed and projected at multiple frame rates (24, 48, and 60 fps), with shutter angles ranging from 180° to 358°, to evaluate viewer preferences. In a paired-comparison paradigm, we assessed preferences along a set of five attributes (realism, motion smoothness, blur/clarity, quality of depth, and overall preference). The resulting data show a clear preference for higher frame rates, particularly when contrasting 24 fps with 48 or 60 fps. We found little impact of shutter angle on viewers' choices, with the exception of one measure (motion smoothness) for one clip type. These data are the first empirical evidence of the advantages afforded by high frame-rate capture and presentation in a cinema context.

Just noticeable differences of listener envelopment and apparent source width

Listener envelopment (LEV) and apparent source width (ASW) are attributes which describe the spatial perception of a sound in a room. They are linked to several parameters of physically measurable binaural room impulse responses (BRIR), e.g., the interaural cross-correlation (IACC). Both the LEV and ASW decrease with increasing IACC. For this study the IACC of the BRIR of different rooms was directly manipulated to systematically change the spatial impression of a sound in a room. The BRIRs were convolved with anechoic music signals, and the resulting stimuli were presented to subjects in a psychoacoustic experiment to estimate the just noticeable differences of LEV and ASW. For that purpose, the subjects had to rate the different stimuli for both perceptual attributes in seven steps from “no envelopment” to “completely enveloped” or from “small” to “wide” respectively. In a second step, the stimuli which were rated the same, were used in a paired comparison paradigm to obtain a more precise estimation of the ability to distinguish between similar stimuli. The results of this study are used in a psychoacoustically motivated model to estimate differences in perceived spaciousness of sounds in rooms by the prediction of the perceived envelopment and source width.

Impact of frequency compression on music perception

Objective: To determine the effects of frequency compression on music perception, and the impact of previous music training and hearing status. It was hypothesized that lesser amounts of compression would be preferred, and that this pattern of preference would be more evident in the musically trained groups. Design: A paired-comparison paradigm was used. Subjects listened to pairs of musical passages as processed by a hearing aid with different frequency-compression settings. Subjects indicated their preferred passage and the strength of their preference. Study sample: Fifty-seven subjects divided in four groups, according to hearing status (normal hearing, mild-to-moderate hearing loss), and previous music experience (trained, not trained). Results: Subjects generally preferred the conditions with the lesser amount of compression. Listeners in the group with previous music training showed stronger preference for less compression than those without training, as did listeners with normal hearing when compared to subjects with hearing loss. Conclusions: Although less frequency compression was in general preferred, there was more variability in the comparisons involving the default settings for a 50-dB hearing loss (i.e. start frequency 4000 Hz, compression ratio 2.5:1) and no compression, suggesting that mild amounts of compression may not be detrimental to perceived sound quality.

Eighteen-month-olds' memory for short movies of simple stories.

This study investigated twenty four 18-month-olds' memory for dynamic visual stimuli. During the first visit participants saw one of two brief movies (30 seconds) with a simple storyline displayed in four iterations. After 2 weeks, memory was tested in the visual paired comparison paradigm in which the familiar and the novel movie were contrasted simultaneously and displayed in two iterations for a total of 60 seconds. Eye-tracking revealed that participants fixated the familiar movie significantly more than the novel movie, thus indicating memory for the familiar movie. Furthermore, time-dependent analysis of the data revealed that individual differences in the looking-patterns for the first and second iteration of the movies were related to individual differences in productive vocabulary. We suggest that infants' vocabulary may be indicative of their ability to understand and remember the storyline of the movies, thereby affecting their subsequent memory.

Do the short‐wave cones signal blueness?

AbstractA simple correspondence between S‐cone response and the sensation of blueness has long been questioned. We measured color appearance using a series of S‐cone isolating stimuli and a paired comparison paradigm to identify a direct correspondence between S‐cone response and perceived hue strength. The results revealed a non‐monotonic reversal in perceived blueness at the unique‐blue line: The S‐cone increment initially increased blueness, but as S‐cone excitation grew past the pure‐blue line, blueness decreased and redness increased. It is difficult to account for this pattern of results by supposing that the sensation of blueness is mediated by a conventional linear channel that extracts (S+M)/L: If the ratio L:M is held constant, the output of such a channel should always increase with increasing S, and so inhibition from a second channel would be needed to account for our result. We also consider another category of explanation: The appearance of a given chromaticity may depend on its position relative to the fundamental axis of daylight locus, which serves as an internalized reference. In an account of the latter kind, there is a systematic mapping between chromaticities and sensations, but there does not need to be a distinct neural signal that represents “blueness.” © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 323–328, 2015

Rett syndrome: an eye‐tracking study of attention and recognition memory

The aim of this study was to examine attention and recognition memory for faces and patterns in Rett syndrome, a severely disabling neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene. Because Rett syndrome impairs speech and hand use, precluding most neuropsychological testing, the visual paired-comparison paradigm (VPC) was used, together with eye tracking. In the VPC, two identical stimuli are presented for familiarization. On test, the familiar stimulus and a new one are paired, and recognition inferred from preferential looking to the novel target. Attention is measured by looking time, gaze dispersion, and number/length of fixations. Twenty-seven female patients with Rett syndrome (mean age 10y 6mo; SD 6y 8mo, age range 2-22y) from the Rett clinic at a children's hospital were assessed in this study, along with 30 age- and sex-matched typically developing participants (outpatients from the same hospital). Although patients with Rett syndrome showed recognition of both faces and patterns, with novelty scores greater than chance (50%), their performance was significantly poorer than that of the typically developing comparison group. Their attention to both was less mature and marked by a more narrowly focused gaze, with fewer and longer fixations. When inspecting faces, attention to the eyes was similar in both groups; however, patients with Rett syndrome tended to ignore the nose and mouth. This is one of the first studies to characterize attention and memory in individuals with Rett syndrome. Visually based techniques, such as the VPC, open a new avenue for quantifying the cognitive phenotype associated with this syndrome.

Listener effort for highly intelligible tracheoesophageal speech

The purpose of this study was to determine whether: (a) inexperienced listeners can reliably judge listener effort and (b) whether listener effort provides unique information beyond speech intelligibility or acceptability in tracheoesophageal speech. Twenty inexperienced listeners made judgments of speech acceptability and amount of effort required to listen to 14 male tracheoesophageal speakers using a paired comparison paradigm. Intelligibility was controlled to limit the analysis to the relationship between ratings of listener effort and speech acceptability. Results showed that as a group, inexperienced listeners reliably rated both speech acceptability and listener effort. In addition, ratings of speech acceptability and listener effort were strongly correlated (r>.99); however, there was evidence that some individual listeners assigned different ratings for each dimension for the same speech samples. Results have important implications for communication success for tracheoesophageal speakers.Learning outcomes: Readers will be able to describe: (a) the measurement of listener burden in speech and (b) the differences and relationships among listener effort, speech acceptability and speech intelligibility.

Judgment of age and attractiveness in a paired comparison task: Testing a picture set developed for diagnosing paedophilia

Purpose. The Not‐Real‐People picture set serves as stimulus material for assessing paedophilic sexual interest. The pictures were generated according to five stages of sexual maturation from infancy to adulthood. While experts seem to be able to discern between the pictures based on maturity levels for a nude variant of the stimuli, it remained unclear whether lay persons would be able to reliably distinguish between picture of clothed individuals from various maturity levels. Methods. Heterosexual university students (52 females, 50 males) participated in a paired comparison task, deciding which of the persons shown on two pictures was younger and which one was more attractive. Additionally, reaction times were recorded. Results. Both male and female judges were able to differentiate between stimuli from the opposite sex with regard to age: the perception of the stages of pubertal development conformed to a measurement on a ratio scale. Similarly, the decisions on attractiveness of the categories were in accordance with a ratio scale. Male participants favoured adolescent and adult female stimuli. Contrary to expectation, female participants did not show a preference for any single age category. Conclusions. The stimuli appear suitable for diagnostic purposes. The participants' decisions reflect the inherent maturity levels of the persons depicted. Reaction times in the paired comparison paradigm increase with task difficulty (i.e., similitude of pictures). The implications for indirect measures of sexual interest, based on reaction times, are discussed.

The effect of contrast intensity and polarity in the achromatic watercolor effect

The watercolor effect (WCE) is a filling-in phenomenon in a region demarcated by two thin abutting lines. The perceived chromaticity of the region is similar to that of the interior line. We develop a series of achromatic WCE stimuli to induce lightness changes analogous to the induced chromaticity in the chromatic version of the WCE. We use a variation of the paired-comparison paradigm to quantify the induced lightness of the filled-in regions to regions with real luminance variations. The luminance of the inner line is fixed, while the luminance of the outer line varies across stimuli. Data from seven subjects (five naive) confirm that an achromatic WCE exists. Moreover, outer lines with both high and low luminances can generate a WCE with an inner line of a moderate luminance. All subjects show a single peak of the effect strength for both polarity conditions, which is never at the extreme luminance levels. Most subjects show an inverted U curve for effect strength as a function of the contrast of the outer lines against the background. Results suggest that the contrast difference between the outer line and the inner line affects the existence and the strength of the achromatic WCE in a nonlinear way.