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Models of perceived affective quality of soundscapes have been recently included into standards to guide the measurement and improvement of urban soundscapes. Such models have been developed in outdoor contexts and their validity in indoor built environments is unclear. A laboratory listening test was performed in a mock-up living room with a window sight, in order to develop an indoor soundscape model for residential buildings. During the test, 35 participants were asked to rate 20 different scenarios each. Scenarios were defined by combining four indoor sound sources and five urban environments, filtered through a window ajar, on 97 attribute scales. By applying principal component analysis, Comfort, Content, and Familiarity, were extracted as the main perceptual dimensions explaining respectively 58%, 25% and 7% of the total variance. Relationships between the principal component scores, acoustic parameters and indoor and outdoor sound categories were investigated. Comfort, Content, and Familiarity were found to be better predicted respectively by loudness N10, level variability LA10-LA90 and sharpness S. The magnitude of linear-mixed-effect model predictions sensibly improved by accounting for sound categories, thus pointing at the importance of semantic meaning of sounds in indoor soundscape assessment. A measurement system is proposed, based on a 2-D space defined by two orthogonal axes, Comfort and Content, and two additional axes, Engagement and Privacy – Control, rotated 45° on the same plane. The model indicates the perceptual constructs to be measured (e.g. in post-occupancy evaluations), the attribute scales to be employed and actions to improve indoor soundscape quality, thus providing a reference for both research and practice.

In birds and higher mammals, auditory experience during development is critical to discriminate sound patterns in adulthood. However, the neural and molecular nature of this acquired ability remains elusive. In fruit flies, acoustic perception has been thought to be innate. Here we report, surprisingly, that auditory experience of a species-specific courtship song in developing Drosophila shapes adult song perception and resultant sexual behavior. Preferences in the song-response behaviors of both males and females were tuned by social acoustic exposure during development. We examined the molecular and cellular determinants of this social acoustic learning and found that GABA signaling acting on the GABAA receptor Rdl in the pC1 neurons, the integration node for courtship stimuli, regulated auditory tuning and sexual behavior. These findings demonstrate that maturation of auditory perception in flies is unexpectedly plastic and is acquired socially, providing a model to investigate how song learning regulates mating preference in insects., eLife digest Many mammals and birds have a critical period in youth when hearing the vocal cues of their parents helps them to learn the specific features of their communication sounds. Scientists have been studying the brains of humans, birds and other animals to find out what is happening in their brains when the animals hear these sounds. However, the brains of these species are too complex to fully understand how early vocal influences shape the brain networks that control behavior. Therefore, scientists often use ‘simpler’ organisms, such as insects, to study these processes. For example, fruit flies use a series of courtship behaviors – including mating calls – to attract their potential mates. To produce a courtship song, males vibrate their wings, which consists of short pulsed songs and sequences of humming. The time interval between the pulses is specific to a species. Until now it was thought that these mating calls are innate behaviors that cannot be learned or modified. To test this, Li et al. clipped the wings of male fruit flies so they could not produce their own song. First, they placed the females with the males and played one species-specific courtship song, and one from a different species. Both songs resulted in successful copulation and did not affect the female’s choice. To find out if a previous experience of a courtship song can influence the behavior of the fruit flies, Li et al. raised one group hearing their species-specific song and the other with a song from a different species. The results showed that females growing-up with their species-specific song, rejected males when a song of another species was played. However, the females accustomed to the other species’ song did not change their song preference and receptivity towards males. The same was also true for males: male fruit flies raised with their species-specific song later ignored another species’ song, which usually increased their mating drive. Li et al. further identified a specific region in the brain of the fruit flies known to be important for courtship, and a key molecule that regulated this behavior. These findings suggest that far from being innate, the mating preference in fruit flies can be learned and influenced by social experience. A next step will be to find out if fruit flies also have critical period for learning vocal cues and if so, how it is regulated at the molecular and neural levels. A better understanding of how fruit flies learn and discriminate sounds may bridge knowledge gaps in research using humans and other mammals.

[EN] Acoustic perception in concert halls has been a topic of research of great interest over the last century. It has been studied through physical and subjective parameters. Nevertheless, a concert in an auditorium is a multi-sensorial experience; so that the acoustic perception may be influenced by other non-acoustical attributes. Therefore, the aim of the present study was to analyze whether architectural variables (visual component) affect acoustic perception in concert halls and quantify this influence. This analysis was carried out implementing the Semantic Differential method and differentiating among experts and non-experts users. A total of 310 subjects assessed in situ 17 concert halls. Results showed that acoustic perception was influenced by the visual component, and acoustic parameters had an influence on architecture as well. However, when separating both groups, it was found that experts were able to isolate acoustic variables from architecture when evaluating the sound quality of a venue. © 2016 Elsevier Ltd, This research was supported by Ministerio de Economia y Competitividad, Spain (project TIN2013-45736-R).

Humans have a strong tendency to spontaneously group visual or auditory stimuli together in larger patterns. One of these perceptual grouping biases is formulated as the iambic/trochaic law, where humans group successive tones alternating in pitch and intensity as trochees (high-low and loud-soft) and alternating in duration as iambs (short-long). The grouping of alternations in pitch and intensity into trochees is a human universal and is also present in one non-human animal species, rats. The perceptual grouping of sounds alternating in duration seems to be affected by native language in humans and has so far not been found among animals. In the current study, we explore to which extent these perceptual biases are present in a songbird, the zebra finch. Zebra finches were trained to discriminate between short strings of pure tones organized as iambs and as trochees. One group received tones that alternated in pitch, a second group heard tones alternating in duration, and for a third group, tones alternated in intensity. Those zebra finches that showed sustained correct discrimination were next tested with longer, ambiguous strings of alternating sounds. The zebra finches in the pitch condition categorized ambiguous strings of alternating tones as trochees, similar to humans. However, most of the zebra finches in the duration and intensity condition did not learn to discriminate between training stimuli organized as iambs and trochees. This study shows that the perceptual bias to group tones alternating in pitch as trochees is not specific to humans and rats, but may be more widespread among animals.

Metrical phonology is the perceptual “strength” in language of some syllables relative to others. The ability to perceive lexical stress is important, as it can help a listener segment speech and distinguish the meaning of words and sentences. Despite this importance, there has been little comparative work on the perception of lexical stress across species. We used a go/no-go operant paradigm to train human participants and budgerigars (Melopsittacus undulatus) to distinguish trochaic (stress-initial) from iambic (stress-final) two-syllable nonsense words. Once participants learned the task, we presented both novel nonsense words, and familiar nonsense words that had certain cues removed (e.g., pitch, duration, loudness, or vowel quality) to determine which cues were most important in stress perception. Members of both species learned the task and were then able to generalize to novel exemplars, showing categorical learning rather than rote memorization. Tests using reduced stimuli showed that humans could identify stress patterns with amplitude and pitch alone, but not with only duration or vowel quality. Budgerigars required more than one cue to be present and had trouble if vowel quality or amplitude were missing as cues. The results suggest that stress patterns in human speech can be decoded by other species. Further comparative stress-perception research with more species could help to determine what species characteristics predict this ability. In addition, tests with a variety of stimuli could help to determine how much this ability depends on general pattern learning processes versus vocalization-specific cues. Electronic supplementary material The online version of this article (doi:10.1007/s10071-016-0968-3) contains supplementary material, which is available to authorized users.

This paper focuses on the acoustic perception of professional musicians performing on a stage or in an orchestra pit. A questionnaire was used to obtain a 'priority classification' of acoustical attributes to describe their requirements. The Borda count was chosen as the analysis method. As it is not suggested for subjective data ascribed to ordinal scales, it has been validated through a comparison with the more rigorous and suitable Condorcet method and a modified version of this method. The uncertainty assessment was taken into account and the Normalized Error was used to compare the results related to five orchestra-concert hall configurations and one orchestra-opera house configuration. The factors that influence the ranking have been investigated and the different acoustical conditions in the auditorium do not seem to have affected the answers. The results suggest the existence of possible orchestra and stage effects or other unknown systematic effects which were not considered in the final classification. The attributes pertaining to the accuracy of ensemble playing and the playing technique were judged to be more important than those related to the stage or pit acoustics, even though the quality of the playing aspects depends on the acoustics.

The effect of stimulus intensity (sound pressure level, SPL) of auditory stimuli on the BOLD response in the auditory cortex was investigated in 14 young and healthy subjects, with no hearing abnormalities, using echo-planar, functional magnetic resonance imaging (fMRI) during a verbal and a non-verbal auditory discrimination task. The stimuli were presented block-wise at three different intensities: 95, 85 and 75 dB (SPL). All subjects showed fMRI signal increases in superior temporal gyrus (STG) covering primary and secondary auditory cortex. Most importantly, the spatial extent of the fMRI response in STG increased with increasing stimulus intensity. It is hypothesized that spreading of excitation is associated with the encoding of increasing stimulus intensity levels. In addition, we found bifrontal activation supposedly evoked by the auditory-articulary loop of working memory. The results presented here should assist in the design of optimal activation strategies for studying the auditory cortex with fMRI paradigms and may help in understanding intensity coding of auditory stimuli.