A general auditory bias for handling speaker variability in speech? Evidence in humans and songbirds

Different speakers produce the same speech sound differently, yet listeners are still able to reliably identify the speech sound. How listeners can adjust their perception to compensate for speaker differences in speech, and whether these compensatory processes are unique only to humans, is still not fully understood. In this study we compare the ability of humans and zebra finches to categorize vowels despite speaker variation in speech in order to test the hypothesis that accommodating speaker and gender differences in isolated vowels can be achieved without prior experience with speaker-related variability. Using a behavioral Go/No-go task and identical stimuli, we compared Australian English adults’ (naïve to Dutch) and zebra finches’ (naïve to human speech) ability to categorize / I/ and /ε/ vowels of an novel Dutch speaker after learning to discriminate those vowels from only one other speaker. Experiments 1 and 2 presented vowels of two speakers interspersed or blocked, respectively. Results demonstrate that categorization of vowels is possible without prior exposure to speaker-related variability in speech for zebra finches, and in non-native vowel categories for humans. Therefore, this study is the first to provide evidence for what might be a species-shared auditory bias that may supersede speaker-related information during vowel categorization. It additionally provides behavioral evidence contradicting a prior hypothesis that accommodation of speaker differences is achieved via the use of formant ratios. Therefore, investigations of alternative accounts of vowel normalization that incorporate the possibility of an auditory bias for disregarding inter-speaker variability are warranted.Publisher PDFPeer reviewe

Release of Soluble Receptors for Tumor Necrosis Factor in Clinical Sepsis and Experimental Endotoxemia

To assess the role of tumor necrosis factor (TNF) in the appearance of soluble TNF receptors (sTNFRs), 20 consecutive patients with a clinical diagnosis of sepsis were studied as were 7 chimpanzees after administration of endotoxin (4 ng/kg) with or without pentoxifylline. The patients had markedly elevated serum levels of sTNFR-p55 and sTNFR-p75 compared with healthy controls (P < .0001 for both receptors). The levels of both soluble receptors correlated with simultaneously measured immunoreactive TNF concentrations (p55: r = .63, P < .01; p75: r = .69, P < .001). In the chimpanzees, endotoxin induced subsequent rises in the serum concentrations ofTNF and sTNFRs. Although pentoxifylline reduced the TNF response to intravenous endotoxin to 20% (P < .05), the appearance of sTNFRs was only moderately inhibited (sTNFR-p55 to 79% on average, P < .05; sTNFR-p75 to 77%, P = .12). These results indicate that TNF either does not play an important role in the appearance of sTNFRs in systemic infection or that a small amount ofTNF remaining in the circulation after some bacterial challenges is sufficient to preserve the secretion of its soluble receptor

ОБМЕН СООБЩЕНИЯМИ В МИКС-СЕТЯХ

Рассмотрена идея Д.Чаума организации анонимной микс-сети с пересылкой сообщений через каскад миксов (передаточных узлов) и последовательным шифрованием всех промежуточных результатов. Описаны задачи, решаемые миксами в ходе обеспечения анонимности связи, обговариваются проблемы ее безопасности

Precursors of Music and Language in Animals

Language and music are universal human traits, raising the question for their evolutionary origin. This chapter takes a comparative perspective to address that question. It examines similarities and differences between humans and non-human animals (mammals and birds) by addressing whether and which constituent cognitive components that underlie the human ability for language and music can be found in non-human animals. It first provides an introduction to the nature and meaning of vocalizations and non-vocal communicative sounds in non-human animals. Next it reviews experimental and observational evidence of animal perception of various frequency and temporal dimensions of sounds. Many animal species show perceptual and cognitive abilities to distinguish between or to generalize auditory stimuli. This includes evidence of the presence of one or more of the constituent cognitive components on which the human abilities for language and music are based, or that may have served as precursors for these components. At the same time, there are also important differences among animal species in their abilities. Hence contrasts are not limited to those between humans and other animal species. The differences between humans and other species, as well as those among non-human species, might result from specific biases and the weight or priority certain species give to attending to certain features of an acoustic signal, or because different species use particular mechanisms to different degrees

Определение состояния атмосферного воздуха в зоне воздействия Сорского горно-обогатительного комбината на основе оценки показателей состояния снежного покрова (Республика Хакасия)

SummaryAlthough prothrombin complex concentrate (PCC) is increasingly used for the treatment of trauma-induced coagulopathy, few studies have investigated the impact and safety of PCC for this indication. The present study was performed to assess PCC for treatment of coagulopathy after blunt liver injury under severe hypothermia. Coagulopathy in 14 anaesthetised pigs was induced by haemodilution. Subsequently, standardised blunt liver injury was induced under severe hypothermia (32.8–33.2°C). Animals were randomised to receive either PCC (35 IU kg-1) or saline (control). Coagulation was assessed over the following 2 hours by thromboelastometry and thrombin generation. Internal organs were examined to determine presence of emboli. The administration of PCC showed a significant reduction in blood loss (p=0.002 vs. controls) and a significant increase in the rate of survival (p=0.022 vs. controls). Plasma thrombin generation in the PCC group increased considerably above baseline levels, with significant increases in peak thrombin levels and endogenous thrombin potential versus controls throughout the follow-up period. In addition, PT decreased significantly in the PCC group versus the control group. However, only slight improvements in thromboelastometry variables were observed. Histology showed an equal degree of liver injury in both groups, and no thromboembolism. In severely hypothermic pigs, the application of PCC corrected trauma-induced coagulopathy and reduced blood loss. Thus, the infusion of PCC might be a reasonable approach to reduce the need for blood cell transfusion in trauma. Furthermore, the impact and safety of PCC application can be monitored through thrombin generation and thromboelastometry under hypothermia.Note: This study was performed at the RWTH Aachen University Hospital, Pauwelsstrasse 30, D-52074 Aachen, Germany.</jats:p

Zebra finches (Taeniopygia guttata) demonstrate cognitive flexibility in using phonology and sequence of syllables in auditory discrimination

Zebra finches rely mainly on syllable phonology rather than on syllable sequence when they discriminate between two songs. However, they can also learn to discriminate two strings of containing the same set of syllables by their sequence. How learning about the phonological characteristics of syllables and their sequence relate to each other and to the composition of the stimuli is still an open question. We compared whether and how the zebra finches’ relative sensitivity for syllable phonology and syllable sequence depends on the differences between syllable strings. Zebra finches were trained in a Go-Left/Go-Right task to discriminate either between two strings in which each string contained a unique set of song syllables or two strings in which both strings contained the same set of syllables, but in a different sequential order. We assessed to what extent the birds in the two experimental groups attend to the spectral characteristics and the sequence of the syllables by measuring the responses to test strings consisting of spectral modifications or sequence changes. Our results showed no difference in the number of trials needed to discriminate strings consisting of either different or identical sets of syllables. Both experimental groups attended to changes in spectral features in a similar way, but the group for which both training strings consisted of the same set of syllables responded more strongly to changes in sequence than the group for which the training strings consisted of different sets of syllables. This outcome suggests the presence of an additional learning process to learn about syllable sequence when learning about syllable phonology is not sufficient to discriminate two strings. Our study thus demonstrates that the relative importance of syllable phonology and sequence depends on which of these features vary among stimuli. This indicates cognitive flexibility in the acoustic features that songbirds might use in their song recognition

Initial results of combined anterior mitral leaflet extension and myectomy in patients with obstructive hypertrophic cardiomyopathy

Objectives. The purpose of this study was to describe the clinical and functional results of combined anterior mitral leaflet extension and myectomy in patients with hypertrophic obstructive cardiomyopathy. Background. Septal myectomy is the most commonly performed surgical procedure in patients with hypertrophic cardiomyopathy and left ventricular outflow tract obstruction. Because of the role of the mitral valve in creating the outflow tract gradient, mitral valve replacement or plication is performed in selected cases in combination with myectomy, often with better hemodynamic results than those of myectomy alone. Mitral valve leaflet extension, in which a glutaraldehyde-preserved autologous pericardial patch is used to enlarge the mitral valve along its horizontal axis, is a novel surgical approach in patients with hypertrophic obstructive cardiomyopathy. Methods. Eight patients with hypertrophic obstructive cardiomyopathy were treated with mitral leaflet extension and myectomy. Preoperative and postoperative data (New York Heart Association functional class, number of drugs prescribed, width of the interventricular septum, severity of mitral valve regurgitation, severity of systolic anterior motion of the mitral valve and outflow tract gradient) were compared with those of 12 patients undergoing myectomy alone. Results. Preoperative evaluation demonstrated that mitral regurgitation and systolic anterior motion of the mitral valve were more severe in the group undergoing mitral valve extension (p < 0.001 and p < 0.05, respectively). There were no deaths associated with either surgical procedure. Two patients, both treated by myectomy alone, died during the follow-up period. Postoperatively, patients treated with mitral valve extension had less mitral regurgitation (p < 0.005), less residual systolic anterior motion (p < 0.01), greater improvement in functional class (p = 0.05) and greater reduction in the number of drugs (p < 0.005) and in septal thickness (p < 0.05). Conclusions. Mitral leaflet extension in combination with myectomy is a promising new surgical approach that may provide superior results to those of myectomy alone. Further studies are needed to determine the clinical value of this procedure

Zebra finches (<i>Taeniopygia guttata</i>) demonstrate cognitive flexibility in using phonology and sequence of syllables in auditory discrimination

Zebra fnches rely mainly on syllable phonology rather than on syllable sequence when they discriminate between two songs. However, they can also learn to discriminate two strings containing the same set of syllables by their sequence. How learning about the phonological characteristics of syllables and their sequence relate to each other and to the composition of the stimuli is still an open question. We compared whether and how the zebra fnches’ relative sensitivity for syllable phonology and syllable sequence depends on the diferences between syllable strings. Two groups of zebra fnches were trained in a Go-Left/Go-Right task to discriminate either between two strings in which each string contained a unique set of song syllables (‘Diferent-syllables group’) or two strings in which both strings contained the same set of syllables, but in a diferent sequential order (‘Same-syllables group’). We assessed to what extent the birds in the two experimental groups attend to the spectral characteristics and the sequence of the syllables by measuring the responses to test strings consisting of spectral modifcations or sequence changes. Our results showed no diference in the number of trials needed to discriminate strings consisting of either diferent or identical sets of syllables. Both experimental groups attended to changes in spectral features in a similar way, but the group for which both training strings consisted of the same set of syllables responded more strongly to changes in sequence than the group for which the training strings consisted of diferent sets of syllables. This outcome suggests the presence of an additional learning process to learn about syllable sequence when learning about syllable phonology is not sufcient to discriminate two strings. Our study thus demonstrates that the relative importance of syllable phonology and sequence depends on how these features vary among stimuli. This indicates cognitive fexibility in the acoustic features that songbirds might use in their song recognition.Animal science