Perceptual Assessment Research Articles

Twenty Eight Days in the Life of a Vocal Pathology: A Case Study of Videolaryngostroboscopy, Acoustic, and Perceptual Variability

The purpose of this investigation was to observe laryngeal tissue and vocal function changes over the course of 28 days in a single participant diagnosed by a laryngologist with bilateral nodules. Laryngeal imaging, acoustic variables and perceptual assessments of voice quality, and perceived vocal effort were obtained every morning for 28 consecutive days. A daily journal of occupational and recreational voice use as well as menstruation and alcohol consumption was maintained each day. It was hypothesized that the laryngeal pathology would appear more extensive and the vocal function measures obtained would be worse following extensive voice use. Laryngeal imaging, acoustic variables, and perceptual measures quantified provided evidence to support the study hypotheses. The size, extent, and asymmetry of the bilateral vocal pathologies observed were more extensive on days following occupational and recreational vocal loading. Acoustic and perceptual measures obtained correlated with the laryngeal tissue changes observed. Study findings support a more holistic approach to laryngeal pathology diagnosis that is based on a more thorough understanding of vocal loading considerations up to 48 hours prior to laryngeal endoscopy to better understand the pathophysiology of the observed lesion(s) for most accurate clinical diagnosis.

Effects of various antipsychotics on driving-related cognitive performance in adults with schizophrenia

The aim of this study was to determine whether the driving-related cognitive performance differs among adults with schizophrenia taking different types of antipsychotics. Neurocognitive performance was assessed using the Cognitive Perceptual Assessment for Driving (CPAD), a computerized battery of tests of visual perception, attention, working memory, reaction time, and inhibitory control for driving ability. One hundred and two adults with schizophrenia who were on antipsychotic monotherapy participated in the study. Of these, 15 were on haloperidol, 28 on risperidone, 14 on olanzapine, 28 on aripiprazole, and 17 on paliperidone. Sixty-four (63%) of the 102 subjects were regarded as competent to drive. Of the subjects taking haloperidol, 33% passed the CPAD, while the passing rates of subjects taking risperidone, olanzapine, aripiprazole, and paliperidone were 57%, 57%, 75%, and 82%, respectively, with a significant difference between the haloperidol and aripiprazole groups (p = 0.005) and between the haloperidol and paliperidone groups (p = 0.001). Additionally, scores on CPAD depth perception (number of correct responses), divided attention, digit span test, and trail-making test B subtests were significantly better for the aripiprazole and paliperidone groups than for the haloperidol and risperidone groups. In this cross-sectional design study, adults with schizophrenia treated with aripiprazole or paliperidone antipsychotic monotherapy demonstrated superior driving-related cognitive performance than those treated with haloperidol or risperidone antipsychotic monotherapy.

Measuring Speech Perception Using the Wide-Range Acoustic Accuracy Scale: Preliminary Findings

Purpose Speech perception requires individuals to hear and differentiate acoustic signals integral to effective communication. Measuring speech perception in children is challenging because speech perception methodology typically requires lengthy experiments that may fatigue children, resulting in limited knowledge of developmental perceptual skills. In this study, we used an adaptive tracking measure along with a wide range of acoustic stimuli to explore how adults, typically developing (TD) children, and children with speech sound disorder (SSD) perceive small acoustic differences in synthetic speech stimuli. Method Twenty-four adults, 15 TD children, and 15 children with SSD between the ages of 7;0–14;0 (years;months) were administered a newly developed perceptual assessment, the Wide-Range Acoustic Accuracy Scale, to determine the just-noticeable difference in discrimination for three separate syllable contrasts. Each syllable contrast varied along a single acoustic parameter: formant transition duration for /bɑ/–/wɑ/, F3 onset frequency for /dɑ/–/ɡɑ/, and F3–F2 distance for /rɑ/–/wɑ/. Results Findings revealed that adults and TD children did not differ in their discrimination of any syllable contrast, but adults significantly differed from SSD children on all syllable contrasts. TD children and children with SSD differed only on the /rɑ/–/wɑ/ contrast. Conclusions Children with SSD demonstrate less accurate and more variable perception skills relative to adults and TD children for /bɑ/–/wɑ/, /dɑ/–/ɡɑ/, and /rɑ/–/wɑ/ syllable contrasts. Clinical implications of the utility of the Wide-Range Acoustic Accuracy Scale are discussed.

The Effectiveness of the Buccal Myomucosal Flap on Speech and Surgical Outcomes in Cleft Palate: A Systematic Review

Purpose: A systematic review was conducted to assess speech and velopharyngeal competence outcomes following the buccal myomucosal flap surgical approach used for primary palatoplasty and secondary surgery for velopharyngeal insufficiency (VPI) in individuals with cleft palate. Methods: A systematic review was guided by the PRISMA guidelines. Articles were included if the patients received the surgical technique for primary cleft palate repair or secondary surgery for VPI and if the study provided detailed methods on the perceptual speech assessment or visualization of postoperative velopharyngeal anatomy. Results: A total of 1013 patients were included from 11 studies. Post-surgery, normal resonance was achieved in 77.4% of patients and no nasal air emission was reported in 54.7% of patients. An improvement in velopharyngeal closure was reported in 81.8% of patients. A variety of perceptual speech assessment scales and methods for assessing velopharyngeal competence were used in the studies. Conclusions: The review suggests that the buccal myomucosal flap procedure results in improved velopharyngeal closure as evidenced by physiologic observation and reported perceptual changes in speech intelligibility, resonance balance, and reduced nasal air emission. The development of an international, standardized method for assessing and reporting speech outcomes and velopharyngeal competency is recommended to ensure accurate comparisons between surgical techniques. Keywords: Buccal flap, systematic review, perceptual speech assessment, speech outcomes, surgical outcomes. Read more →

Polish version of the pediatric Voice Handicap Index (pVHI)

IntroductionThe modern standard of voice diagnostics in both the adult and pediatric populations is based on perceptual, acoustic and videolaryngoscopic assessment, as well as self-assessment of voice quality. Currently, only two tools for assessing the voice in the pediatric population were translated into Polish: pVHI and its abbreviated version - cVHI (Children Voice Handicap Index). Thanks to the use of pVHI, the therapist and the patient, as well as his family and relatives, become aware of what functional zones are disturbed as a result of voice problems. AimThe aim of the study was to analyze various methods of assessing children's voice, including the pVHI voice disability questionnaire in children with various voice disorders. In addition, the authors wanted to develop a classification of the degree of disability of children's voice expressed by the sum of points obtained in pVHI. Material and methodThe study included a group of 89 children aged 5-12. Each child underwent a standard otolaryngological and phoniatric examination procedure with hearing assessment and fiberoscopic laryngeal evaluation. The voice of the dysphonic children was assessed with a spectrogram and the GRBAS scale. The children's guardians completed the Pediatric Voice Handicap Index (pVHI). ResultsPolish children without voice disorders obtained an average of 1.9 points as a total result of the pVHI questionnaire. The results of the questionnaire obtained from children with voice disorders were on average 24.7 (SD 13.9). Total and individual domain scores were significantly higher in children with dysphonia than in asymptomatic children. Children with voice disorders were rated an average of 1.95 (SD 0.6) degree of hoarseness in Yanagihara's scale, and obtained an average overall score of 4.8 on the GRBAS scale (SD 2). A common upward trend in all types of evaluation is evident, along with an increase in the handicap expressed in pVHI score. Statistical analysis showed significant dependence between the overall pVHI score and other voice rating indicators. The result correlated to a moderate degree with the sum of points obtained from GRBAS and the severity of hoarseness assessed subjectively (G) and objectively according to Yanagihara's scale. In addition, weak correlations of the functional part of the questionnaire with the presence of learning problems, and the emotional part with the presence of problems with socialization were noticed. Analyzing the results of the questionnaire depending on the GRBAS results and the Yanagihara scale, a better fit of the exponential trend line than the linear one was observed. The point of inflection of the exponential curve, and thus a significant deterioration in voice assessment indicators, was observed in children who obtained over 32 points, which is 33% of the maximum value that can be obtained from the questionnaire. ConclusionsA new voice assessment tool for the pediatric population has been developed that complements the diagnostic facilities of the otolaryngologist, phoniatrician and speech therapist. Adaptation of the Polish version of the Voice Handicap Index (pVHI) allows the introduction of a new diagnostic indicator into medical and speech therapy practice. The pVHI questionnaire result differentiates children with voice and speech disorders from healthy children. The analysis of children's voice using various methods allows the clinician to further characterize the disturbance of voice quality. It is possible to assess the scale of the severity and type of problem, as well as the spheres of life it concerns most. There is a correlation between the severity of voice disorders and the severity of voice disability expressed in the pVHI question.

Multiparameter Voice Assessment in Dysphonics: Correlation Between Objective and Perceptual Parameters

Perceptual assessment and objective measures of voice provide a quantifiable tool for determining the degree of glottal closure, thus helping to distinguish dysphonic voices from normal voices. The correlation between the perceptual and objective parameters of voice in dysphonic can enable the voice pathologist to be more effective in differentiating the normal voices from dysphonic voices. However, only a few studies have investigated the correlation between these measures. To document the differences in the perceptual and objective parameters of voice in participants with dysphonia and normal controls and to investigate the correlation between the perceptual and objective parameters of voice among participants with dysphonia. This investigation deployed standard group comparison and a retrospective study. Two groups of participants were included in the study. Participants in group 1 were diagnosed as having a voice disorder secondary to organic pathologies and group 2 participants had a clinically normal voice. Phonation samples of all the participants were collected and perceptual analysis was carried out using the GRBAS rating scale. As part of the objective measures, acoustic and cepstral measures were extracted from the phonation samples. The analysis of the results revealed significant differences in perceptual ratings between the normal (control) and dysphonic groups. The mean values of all the objective measures of voice presented significant differences between participants of both groups. The perceptual ratings of grade, breathiness, and roughness showed better correlations with the cepstral measures than with the time-based acoustic measures. Further foraging research on the correlation between perceptual and objective measures of voice in various degrees of dysphonia will improve reliability while discriminating and quantifying hoarse, harsh and breathy voices from modal voices.

Design and Development of a Speech Intelligibility Test Based on Pseudowords in French: Why and How?

Purpose The current intelligibility tests performed on speakers with atypical speech production are limited by the ability of listeners to restore distorted sequences. This results in a measure that is overvalued when compared with the real articulatory performance. In this article, we present a new intelligibility test in order to neutralize the commonly encountered bias in traditional perception-based assessments. We present the construction of the acoustic-phonetic decoding task and its first test during a perceptual judgment test of intelligibility and during a result comparison with a global perceptual evaluation. Method We developed a very large pseudoword directory including about 90,000 forms that respect French phonotactic constraints. From this directory, we have created lists of pseudowords intended to be recorded for the constitution of the corpus. These lists are established due to an algorithm integrating predefined linguistic constraints and produced by 47 speakers (nine healthy and 38 patients). We then performed a perceptual judgment of intelligibility test with 20 listeners who transcribed these productions. Results At the end of the data processing stage, we obtained a Perceived Phonological Deviation (PPD) score for each speaker that reflects the average number of features altered per phoneme. We then compared the PPD score with a global intelligibility score derived from a global perceptual assessment of intelligibility and of the alteration severity. Conclusions The current findings confirm that a speech intelligibility test based on pseudowords in French achieves fine-grained PPD scores, which enables discrimination between patients and healthy speakers. Moreover, the PPD score is related to the global intelligibility score, especially in severity. Further studies are needed to better understand the discrimination power of this intelligibility test based on an acoustic-phonetic decoding task.

The Correlation Between Consonant Articulation and Velopharyngeal Function in Patients With Unoperated Submucous Cleft Palate.

Submucous cleft palate (SMCP) is a congenital condition related to abnormal muscle attachments within the soft palate. Even though hypernasality and nasal emission, the primary symptom of SMCP, have been well-documented, research on articulation errors is currently lacking. The object of this study was to examine the consonant articulation in patients with unoperated SMCP and its possible correlation with the velopharyngeal function. This study analyzed the perceptual speech assessment and nasopharyngoscopy data of 338 patients with unoperated SMCP between years 2008 and 2016 retrospectively. The mean age of the patients was 13.27 years. About 125 patients showed velopharyngeal competence (VPC), 174 velopharyngeal incompetence (VPI), and 39 marginal VPI (MVPI). Among the 338 patients, 137 presented normal articulation, 124 consonant omission, 25 compensatory articulation, 36 consonant weakening, 51 consonant substitution, and 36 posterior placement. About 70.40% VPC patients, 17.24% VPI patients, and 48.72% MVPI patients demonstrated normal articulation. About 59.20% VPI patients showed consonant omission. The results demonstrated that consonant articulation varied among patients with unoperated SMCP and was correlated with their velopharyngeal functions, while consonant omission was the most common articulation error. Velopharyngeal closure pattern was not associated with either velopharyngeal function or consonant articulation.

Perceptual image quality assessment: a survey

Perceptual quality assessmentplays a vital role in the visual communication systems owing to theexistence of quality degradations introduced in various stages of visual signalacquisition, compression, transmission and display.Quality assessment for visual signals can be performed subjectively andobjectively, and objective quality assessment is usually preferred owing to itshigh efficiency and easy deployment. A large number of subjective andobjective visual quality assessment studies have been conducted during recent years.In this survey, we give an up-to-date and comprehensivereview of these studies.Specifically, the frequently used subjective image quality assessment databases are firstreviewed, as they serve as the validation set for the objective measures.Second, the objective image quality assessment measures are classified and reviewed according to the applications and the methodologies utilized in the quality measures.Third, the performances of the state-of-the-artquality measures for visual signals are compared with an introduction of theevaluation protocols.This survey provides a general overview of classical algorithms andrecent progresses in the field of perceptual image quality assessment.

Perceptual quality assessment for multimodal medical image fusion

Recent years have witnessed that the multimodal medical image fusion (MMIF) plays critical roles in clinical diagnostics and treatment. Many MMIF algorithms have been proposed to improve the MMIF images quality. The quality of multimodal medical fused images will significantly affect the results of the clinical diagnosis. However, little work has been designed to evaluate the effectiveness of MMIF algorithms and the quality of MMIF images. To this end, this paper presents a perceptual quality assessment method for MMIF. A MMIF image database (MMIFID) is first built to employ the classical MMIF algorithms, and the subjective experiment is conducted to assess the quality of each fused image. Then, a no-reference objective method is proposed for the perceptual quality evaluation of MMIF images,which uses Pulse Coupled Neural Network (PCNN) in Non-subsampled Contourlet Transform (NSCT). A fused image is decomposed by NSCT into low frequency sub-band (LFS) and high frequency sub-band (HFS). It is used to motivate the PCNN processing, and large firing times are employed to measure LFS and HFS. Finally, two components evaluation results are combined to obtain the overall objective quality score. Experimental results based on the MMIFID indicate that our presented method outperforms the existing image fusion quality evaluation metrics, and it provides a satisfactory correlation with subjective scores, which shows effectiveness in the quality assessment of medical fused images.

The indicators of human capital for hospital-based nursing workforce in Taiwan.

To develop a hospital-based nursing human capital model for Taiwan. Effective nursing management only becomes possible when nurse managers are able to manage and maintain the right equilibrium among human capital components. We developed an analytic hierarchy process (AHP) model with 8 dimensions and 31 indicators based on extensive literature review and experts' perceptual assessment. We used expert and purposive sampling and invited 82 nursing professionals to rate the importance of these dimensions and indicators. The AHP process was performed to identify the weightage and prioritize the dimensions and indicators of the nursing human capital. Our analysis showed that, for nursing human capital, health was the most important factor (weight: 34.8%), followed by employee protection (20.4%), work attitude (13.7%), employee stability (10.8%), general nursing training (6.3%), competencies (5.8%), advanced nursing training (4.3%) and clinical nursing experience (3.9%). The model would be most useful for nurse administrators in long-range strategic management. Specifically, the model can be used as a reference to form a rating system to analyse nursing human capital. Health promotion programs and employee protection measures targeting nurses could improve nursing human capital in hospitals.

Pharyngeal flap for a poorly repaired cleft palate with posterior palatal defect

ObjectivePosterior palatal defect after cleft palate (CP) repair is not a rare problem, it may cause velopharyngeal insufficiency (VPI). The aim of this study was to assess the effectiveness of a superiorly-based pharyngeal flap (PF) with modification of its end to accommodate the defect in treatment of post-palatoplasty VPI. MethodsThirteen children with VPI due to posterior palatal defect after CP repair were included in this study. PF was used in treatment of all patients, the lower end of the flap was fashioned in a V-shape to accustom the shape of the defect with peeling of its overlying mucosa to enhance wound healing. The PF was inserted deeply into a tunnel created within the defect between the oral and nasal layers of the palate. Pre- and postoperative evaluation using auditory perceptual assessment (APA), nasometric assessment and velopharyngoscopy were performed. ResultsSignificant improvement of APA and nasalance score for both oral and nasal sentences was achieved. Also, velopharyngoscopy showed complete velopharyngeal closure in all patients postoperatively. ConclusionA modified PF is an effective treatment for VPI caused by posterior palatal defect that may be encountered after CP repair.

How Does Our Voice Change as We Age? A Systematic Review and Meta-Analysis of Acoustic and Perceptual Voice Data From Healthy Adults Over 50 Years of Age.

Purpose Approximately 30% of adults over the age of 50 years present with altered vocal function. Our understanding of how these changes manifest acoustically and perceptually is derived from relatively modest-sized studies using a diversity of tools. Voice changes can arise from the onset of disease or disorder, but also age-related physiological changes, which may not reflect pathology as such. Here, we bring together data on acoustic, perceptual, and instrumental assessments (electroglottography), with the aim of gaining a better understanding of the changes occurring across these measurement domains. We consider these changes in the context of different acoustic features, software programs, and perceptual protocols. Method Studies of voice function in healthy older adults over the age of 50 years were sought. Literature was systematically searched with 746 abstracts reviewed. Forty-seven studies were included in the review. A meta-analysis of included studies compared voice acoustic parameters between sex and age. Sixteen acoustic parameters collected from 1,475 participants were analyzed in the meta-analysis. These included some previously unpublished analyses using data provided by authors of included studies. Results Data from the systematic review suggest that older individuals are perceived to present with higher overall scores of dysphonia and roughness, breathiness, strain, and instability. Acoustically, males have significantly higher scores on measures of perturbation, including noise-to-harmonic ratio and absolute jitter. The meta-analysis outcomes suggest that participants aged 80-89 years produce significantly higher fundamental frequency, jitter percent, shimmer percent, and shimmer in decibels compared to participants aged 60-69 years and a significant increase in relative average perturbation, jitter percent, and shimmer in decibels compared to participants aged 70-79 years. Limited data were available comparing acoustic measures using the same acoustic software. Conclusions Variations in fundamental frequency and frequency and amplitude perturbation increase as healthy adults age. It was difficult to draw definitive conclusions based on existing literature due to variability in hardware used, limited descriptions of study cohorts, or missing data from statistical analysis. Supplemental Material https://doi.org/10.23641/asha.11868663.

Visitors’ perception based on five physical senses on ecosystem services of urban parks from the perspective of landsenses ecology

ABSTRACTUrban parks not only improve the urban ecology but also provide cultural ecosystem services to city dwellers. This study investigated the relationship between cultural ecosystem services provided by urban parks and visitors’ perception of urban park from the perspective of landsenses ecology. A perceptual indicator system was developed following the analysis of landsense elements among the park elements, for four sensory dimensions. A perceptual assessment model was established using the Importance-Performance Analysis (IPA) method, which could be used to divide the perceptual indicators into five grades. We found that the importance level of perceptual indicators was influenced by the type of park elements and the functional area of the visitors’ sensory apparatus. On the one hand, park elements that are common or can be perceived easily receive more attention. On the other hand, among the distance receptors, wider functional area might be related to the higher importance level of the perceptual indicators; the immediate receptors also have considerable influence on perception since visitors contact with the environment directly through these. The most important indicators were related to vision and touch, including ‘vision of plants’, ‘vision of water’, ‘feel of sunlight’, ‘touch of roads’, and ‘sound of animals’. Furthermore, we conducted an assessment on landsense satisfaction of a typical urban park in Beijing, suggesting ways to improve visitors’ perception of urban parks from the perspective of landsenses ecology. The assessment showed that the urban park design and management practices could be improved to increase visitors’ satisfaction.

Perceptual objective quality assessment of stereoscopic stitched images

Large view stereoscopic images can provide users with immersive depth experience. Image stitching techniques aim to obtain large view stitched images, and there have been various image stitching algorithms proposed recently. However, there is still no effective objective quality assessment for stereoscopic stitched images. In this paper, we propose a new perceptual objective stereoscopic stitched image quality assessment (S-SIQA) method by considering different distortion types in the existing stitching methods, including color distortion, ghost distortion, structure distortion(shape distortion, information loss), and disparity distortion. The quality evaluation methods for these distortion types are designed by using the color difference coefficient, points distance, matched line inclination degree, information loss, and disparity difference. Then we fuse these measures in the proposed S-SIQA model by an optimally weighted linear combination. In addition, to evaluate the performance of the proposed S-SIQA, we build a subjective quality assessment database for stereoscopic stitched images. Experimental results have confirmed the proposed method can effectively measure the perceptual quality of stereoscopic stitched images.

Perceptual and acoustic voice analysis in patients with glottis cancer after endoscopic laser cordectomy.

<b>Introduction:</b> Treatment of glottis cancer, despite oncological safety, should consider postoperative voice quality. CO<sub>2</sub> laser endoscopic cordectomy allows radical removal of the tumor while maintaining respiratory, defensive and phonatory functions. <br><b>The aim:</b> The aim of the study is perceptual and acoustic evaluation of voice in patients after endoscopic CO2 III-Va laser cordectomy due to glottis cancer. <br><b>Material and method:</b> The study included 30 men after CO<sub>2</sub> cordectomy. 13 (43%) patients underwent type III cordectomy, 6 (20%) - type IV; 11 (37%) - type Va. Voice quality has been assessed 6 months after the surgery. Control group included 30 healthy men of the same age. GRBAS scale has been used in perceptual evaluation of voice. Acoustic analysis has been performed using DiagnoScope Specjalista software. Narrowband spectrography and Maximum Phonation Time (MPT) measure has been performed. <br><b>Results:</b> In study group, voice has been classified as G<sub>1</sub>R<sub>1</sub>B<sub>0</sub>A<sub>0</sub>S<sub>0</sub> after type III cordectomy; as G<sub>1</sub>R<sub>1</sub>B<sub>1</sub>A<sub>1</sub>S<sub>2</sub> in type IV and as G<sub>2</sub>R<sub>1</sub>B<sub>1</sub>A<sub>0</sub>S<sub>3</sub> in type Va. Acoustic evaluation revealed the highest values of F0, Jitter, Shimmer and NHR after Va cordectomy as well as non-harmonic components in narrowband spectrography and reduction of MPT. <br><b>Conclusions:</b> Postoperative voice quality depends on the type of cordectomy. Perceptual assessment indicates that type IV and Va cordectomy cause intensification of voice disorders. Parameters of acoustic evaluation increase with the extent of the procedure. The presence of non-harmonic components in narrowband spectrography increases with the extent of cordectomy, such as the reduction of MPT. Preservation of anterior commissure influences good voice quality in perceptual and acoustic assessment.

Cerebral visual impairment captured with a structured history inventory in extremely preterm born children aged 6.5 years

To investigate whether a questionnaire can identify cerebral visual impairment (CVI) in a group of 6.5-year-old children born extremely preterm (EPT) as accurately as direct assessments. This prospective population-based study included 120 children born before 27weeks' gestational age (66 males; mean, 25.4±1.0weeks) and 97 full-term controls (56 males; mean, 39.9±1.1weeks) at the age of 6.5years, as part of the Extremely Preterm Infants in Sweden Study (EXPRESS). A questionnaire for detection of CVI was evaluated and compared with visual, perceptual, and cognitive assessments. Parents of children born EPT reported more CVI features than the parents of control children, with median sum scores of 25 (95% CI, 18.1-31.9) and 11 (95% CI, 8.8-13.2), respectively (P<0.001), and a median difference of 14 (95% CI, 6.6-21.4). Low rates of reported CVI features were significantly associated with better results from direct assessments within the EPT group and with less pronounced differences compared to controls. The questionnaire discriminated well between children born EPT and controls, and the scores were congruent with other evidence of visual, perceptual, and cognitive deficits. The easily used questionnaire compared favorably with direct assessment in identifying CVI in children born EPT and also provides valuable information to clinicians, and parents about the daily life problems associated with CVI.

Visual snow syndrome: a review on diagnosis, pathophysiology, and treatment.

Visual snow is considered a disorder of central visual processing resulting in a perturbed perception of constant bilateral whole-visual field flickering or pixelation. When associated with additional visual symptoms, it is referred to as visual snow syndrome. Its pathophysiology remains elusive. This review highlights the visual snow literature focusing on recent clinical studies that add to our understanding of its clinical picture, pathophysiology, and treatment. Clinical characterization of visual snow syndrome is evolving, including a suggested modification of diagnostic criteria. Regarding pathophysiology, two recent studies tested the hypothesis of dysfunctional visual processing and occipital cortex hyperexcitability using electrophysiology. Likewise, advanced functional imaging shows promise to allow further insights into disease mechanisms. A retrospective study now provides Class IV evidence for a possible benefit of lamotrigine in a minority of patients. Scientific understanding of visual snow syndrome is growing. Major challenges remain the subjective nature of the disease, its overlap with migraine, and the lack of quantifiable outcome measures, which are necessary for clinical trials. In that context, refined perceptual assessment, objective electrophysiological parameters, as well as advanced functional brain imaging studies, are promising tools in the pipeline.

Students take charge of Learning – Using e-learning in Perceptual Assessment in Speech–Language Pathology

ABSTRACT Perceptual assessment is the basis for diagnosis and evaluation of treatment in speech–language pathology (SLP). Students need to practise assessment skills. A web-based platform with cases and expert feedback in cleft palate disorders was developed in national collaboration. The aim of the study was to evaluate the results of individual training on assessment skills in SLP students and their perception of e-learning. Forty-five students performed tests using a pre- and post-test set-up. Perceptual assessments were demonstrated and instructions provided during teacher-led activities in ongoing fully scheduled courses; students were then individually trained in their free time. Reference samples were available. A significant improvement was found in rating and phonetic transcriptions after training. Positive comments concerned accessibility and practice time.

Perceptual Quality Assessment of Enhanced Images Using a Crowd-Sourcing Framework

In this work, we present a psychophysical study, in which, we analyzed the perceptual quality of images enhanced with several types of enhancement algorithms, including color, sharpness, histogram, and contrast enhancements. To estimate and compare the qualities of enhanced images, we performed a psychophysical experiment with 35 source images, obtained from publicly available databases. More specifically, we used images from the Challenge Database, the CSIQ database, and the TID2013 database. To generate the test sequences, we used 12 different image enhancement algorithms, generating a dataset with a total of 455 images. We used a Double Stimulus Continuous Quality Scale (DSCQS) experimental methodology, with a between-subjects approach where each subject scored a subset of the total database to avoid fatigue. Given the high number of test images, we designed a crowd-sourcing interface to perform an online psychophysical experiment. This type of interface has the advantage of making it possible to collect data from many participants. We also performed an experiment in a controlled laboratory environment and compared its results with the crowd-sourcing results. Since there are very few quality enhancement databases available in the literature, this works represents a contribution to the area of image quality.