The incongruency advantage for environmental sounds presented in natural auditory scenes

The effect of context on the identification of common environmental sounds (e.g., dogs barking or cars honking) was tested by embedding them in familiar auditory background scenes (street ambience, restaurants). Initial results with subjects trained on both the scenes and the sounds to be identified showed a significant advantage of about five percentage points better accuracy for sounds that were contextually incongruous with the background scene (e.g., a rooster crowing in a hospital). Further studies with naive (untrained) listeners showed that this incongruency advantage (IA) is level-dependent: there is no advantage for incongruent sounds lower than a Sound/Scene ratio (So/Sc) of -7.5 dB, but there is about five percentage points better accuracy for sounds with greater So/Sc. Testing a new group of trained listeners on a larger corpus of sounds and scenes showed that the effect is robust and not confined to a specific stimulus set. Modeling using spectral-temporal measures showed that neither analyses based on acoustic features, nor semantic assessments of sound-scene congruency can account for this difference, indicating the IA is a complex effect, possibly arising from the sensitivity of the auditory system to new and unexpected events, under particular listening conditions.     

How to select stimuli for environmental sound research and where to find them

A major methodological challenge in environmental sound research is to select appropriate stimuli. When an experiment involves a large number of sound sources, making custom recordings or producing sounds live is frequently impractical or, for certain sounds, impossible. Existing databases of environmental sound recordings provide a researcher with a useful alternative. However, finding and selecting suitable sounds in such databases can be difficult because of the great variety of sounds present, poor documentation, questionable recording quality, and required purchasing costs. This article describes a number of practical issues to consider during the stimulus selection process, offers a preliminary compilation of existing resources for obtaining environmental sound recordings, provides some normative perceptual data that can be used as a reference for selecting stimuli and evaluating performance, and lists required characteristics and structural aspects of a research-oriented environmental sound database.     

The Constitution as an Axiomatic System

The Constitution is considered as an informal axiomatic system. The strategy proposed by the authors rests on the following propositions: (1) axioms are considered as contextual definitions of those concepts by means of which they are formulated; and (2) the main requirement for this type of system is internal consistency. The first proposition is necessary for considering the Constitution as an informal axiomatic system, while the second is sufficient, because the approach proposed, apart from consistency, must certainly consider the requirements for formal axiomatic systems, such as independence and completeness. The authors argue that the Constitution can be compared to axiomatic constructions in modern science in the sense that is given in the research on the logic and methodology of deductive sciences. This analogy is appropriate to the extent to which constitutional provisions are interpreted as the basic elements of the legal system, just as in the formal sciences axioms are regarded as basic principles that define the main features of the formal system. This means that the Constitution itself is seen as coherent, consistent discourse that contextually defines the meaning of the basic terms of the legal system.     

Variable Perception of White Noise in Ambiguous Phonetic Contexts: The Case of /p/ and /f/

The roles of spectro-temporal coherence, lexical status, and word position in the perception of speech in acoustic signals containing a mixture of speech and nonspeech sounds were investigated. Stimuli consisted of nine (non)words in which either white noise was inserted only into the silent interval preceding and/or following the onset of vocalic transitions ambiguous between /p/ and /f/, or in which white noise overlaid the entire utterance. Ten listeners perceived 85% /f/s when noise was inserted only into the silent interval signaling a stop closure, 47% /f/s when noise overlaid the entire (non)words, and 1% in the control condition that contained no noise. Effects of spectro-temporal coherence seemed to have dominated perceptual outcomes, although the lexical status and position of the critical phoneme also appeared to affect responses. The results are explained more adequately by the theory of Auditory Scene Analysis than by the Motor Theory of Speech Perception.     

Use of Integrity Tests May Reduce Workers’ Compensation Losses

Purpose  

The purpose of this study was to examine whether the use of integrity tests in personnel selection would reduce the cost of worker’s compensation claims in organizations representing four different industries.     

The Role of Native-Language Phonology in the Auditory Word Identification and Visual Word Recognition of Russian–English Bilinguals

Does native language phonology influence visual word processing in a second language? This question was investigated in two experiments with two groups of Russian-English bilinguals, differing in their English experience, and a monolingual English control group. Experiment 1 tested visual word recognition following semantic categorization of words containing four phonological vowel contrasts (\({/{{\rm i}}/-/{{\rm u}}/, /{{\rm I}}/-/\wedge/, /{{\rm i}}/-/{{\rm I}}/, /{{\varepsilon}}/-/\ae/}\)). Experiment 2 assessed auditory identification accuracy of words containing these four contrasts. Both bilingual groups demonstrated reduced accuracy in auditory identification of two English vowel contrasts absent in their native phonology (\(/{{\rm i}}/-/{{\rm I}}/, /{\varepsilon}/-/\ae/\)). For late- bilinguals, auditory identification difficulty was accompanied by poor visual word recognition for one difficult contrast (/i/-/I/). Bilinguals’ visual word recognition moderately correlated with their auditory identification of difficult contrasts. These results indicate that native language phonology can play a role in visual processing of second language words. However, this effect may be considerably constrained by orthographic systems of specific languages.     

How to select stimuli for environmental sound research and where to find them.

A major methodological challenge in environmental sound research is to select appropriate stimuli. When an experiment involves a large number of sound sources, making custom recordings orproducing sounds live is frequently impractical or, for certain sounds, impossible. Existing databases of environmental sound recordings provide a researcher with a useful alternative. However, finding and selecting suitable sounds in such databases can be difficult because of the great variety of sounds present, poor documentation, questionable recording quality, and required purchasing costs. This article describes a number of practical issues to consider during the stimulus selection process, offers a preliminary compilation of existing resources for obtaining environmental sound recordings, provides some normative perceptual data that can be used as a reference for selecting stimuli and evaluating performance, and lists required characteristics and structural aspects of a research-oriented environmental sound database.