Affect as a Component of Perceived Sound and Vibration Quality in Aircraft

The concept of product sound quality is becoming an integral component of product development and design. The research presented in this thesis test the notion that affective reactions (i.e. positive-negative feelings) are a major determinant of perceived sound quality. A secondary aim is to test the effects of additional modalities (vision and tactile senses) on affective reactions. Paper I focused on assessing affective reactions to and cognitive evaluations of set of interior aircraft sounds. An additional aim was to study the relationship between affective reactions and physical measures. In addition, the relation between affect, annoyance and overall rated quality was investigated. Paper II focused on comparing affective reactions and affective evaluations. To further test the link between physical properties and affect, a different set of sounds was also included. Paper III highlighted the affect-physical measures relationship by using a set of systematically synthesized sounds. Paper III also more explicitly addressed the correlation between affective reactions and annoyance ratings. In Paper IV attention was directed to multimodal (sound and vibration) perception and how sound and vibration combinations influenced affective reactions and preference. Finally, Paper V examined the combined effect of three types of stimuli, auditory, tactile and visual on affective reactions, sound quality evaluation, and perceived presence. The results provided strong support for the hypothesis that affective reactions to auditory stimuli can be described by the two fundamental affect dimensions of valence (positive-negative) and activation (deactivated-activated). The results further showed that valence and activation had different psychoacoustical determinants. The valence dimension was related to loudness, whereas the activation dimension should be related to sharpness (positive correlation) and tonal content (negative correlation). In addition, correlational analyses showed that a large component of the variance in quality ratings was accounted for by the valence and activation measures. Another major finding was that multimodal affective perception of an environment (e.g. auditory and tactile/visual) differed from unimodal perception (auditory only), where multi-modal perception has both discounting and augmenting effects on affective reactions and sound quality evaluation. Taken together, the current research suggests that affective reactions are fundamental to perception of auditory stimuli and is thus an integral part of the evaluation of sound quality. In addition, both sound characteristics and input from non-auditory modalities influence affective reactions in an aircraft environment. One approach to improve sound quality is to investigate affective reactions to product sounds

Attentional and emotional prioritization of the sounds occurring outside the visual field

The ability to detect and localize sounds in an environment is critical for survival. Localizing sound sources is a computational challenge for the human brain because the auditory cortex seems to lack a topographical space representation. However, attention and task demands can modulate localization performance. Here, we investigated whether the localization performance for sounds occurring directly in front of or behind people could be modulated by emotional salience and sound-source location. We measured auditory-induced emotion by ecological sounds occurring in the frontal or rear perceptual fields, and employed a speeded localization task. The results showed that both localization speed and accuracy were higher, and that stronger negative emotions were induced when sound sources were behind the participants. Our results provide clear behavioral evidence that auditory attention can be influenced by sound-source location. Importantly, we also show that the effect of spatial location on attention is mediated by emotion, which is in line with the argument that emotional information is prioritized in processing. Auditory system functions as an alarm system and is in charge of detecting possible salient events, and alarming for an attention shift. Further, spatial processing in the auditory dorsal pathway has a function of guiding the visual system to a particular location of interest. Thus, an auditory bias toward the space outside the visual field can be useful, so that visual attention could be quickly shifted in case of emotionally significant information

Auditory-Induced Emotion: A neglected channel for Communication in Human-Computer Interaction.

Interpreting and responding to affective states of a user is crucial for future intelligent systems. Until recently, the role of sound in affective responses has been frequently ignored. This article provides a brief overview of the research targeting affective reactions to everyday, ecological sounds. This research shows that the subjective interpretation and meaning that listeners attribute to sound, the spatial dimension, or the interactions with other sensory modalities, are as important as the physical properties of sound in evoking an affective response. Situation appraisal and individual differences are also discussed as factors influencing the emotional reactions to auditory stimuli. A study with heartbeat sounds exemplifies some of the introduced ideas and research methodologies, and shows the potential of sound in inducing emotional states

The influence of meaning on noise annoyance from varied spectral

Spectral balance (the relation between high and low frequencies) is an auditory metric thatcorrelates with annoyance. However, previous research has shown conflicting results whereincreased annoyance has been linked to both increased high frequency content [1] and lowfrequency content [2]. The aim of this research is to test the hypothesis that the informationcontent of the signal could be a contributing factor to this discrepancy. An experiment wasperformed where participants rated sounds with different spectral slopes (flat, 3.5 dB/oct, 5.5dB/oct and 7.5 dB/oct) and different information content (varying from original recording of atruck sound to a noise spectrum). The results showed that different spectral slopes werepreferred for different levels of information content

Validation of a Swedish short self-report measure of core affect

This research aimed at validating two self-report composite rating scales of core affect that are useful when quick assessments are required, for instance, of current mood or recalled, anticipated, and experienced emotional reactions. The ratings were derived from the Swedish Core Affect Scales (SCAS) comprising six self-report rating scales of the two orthogonal dimensions of core affect, valence (unpleasantness-pleasantness) and activation (quietness-excitement). In three samples of university students who were requested to rate current moods, affect-inducing sounds, or affect-inducing pictures, the composite ratings were compared to SCAS, two widely used graphical rating scales of valence and activation, and skin conductance responses and the acceleratory peak of heart rate. Three different rating formats were also compared. The results showed that the composite ratings were reliable and yielded the expected correlations with the other ratings and with the physiological affect indicators. No effects of rating format were detected. It is concluded that the composite ratings of valence and activation may be used if quick assessments are called for. Choices can be made of any of three rating formats depending on purpose with the assessments

Auditory-Induced Emotion: A neglected channel for Communication in Human-Computer Interaction.

Interpreting and responding to affective states of a user is crucial for future intelligent systems. Until recently, the role of sound in affective responses has been frequently ignored. This article provides a brief overview of the research targeting affective reactions to everyday, ecological sounds. This research shows that the subjective interpretation and meaning that listeners attribute to sound, the spatial dimension, or the interactions with other sensory modalities, are as important as the physical properties of sound in evoking an affective response. Situation appraisal and individual differences are also discussed as factors influencing the emotional reactions to auditory stimuli. A study with heartbeat sounds exemplifies some of the introduced ideas and research methodologies, and shows the potential of sound in inducing emotional states

Emotional bias in change deafness in multisource auditory environments

Theories of auditory attention suggest that humans decompose complex auditory input into individual auditory objects, which then compete for attention to dominate auditory perception. Since emotional significance of external stimuli has been argued to provide cues for sensory prioritization and allocation of attention, emotionally salient auditory objects can receive attention to dominate auditory perception. On the basis of the function of audition as an alarm system that informs the organism about its immediate surroundings, and on empirical evidence that emotion can modulate auditory perception, we argue that auditory stimuli with greater emotional saliency would dominate perception in multisource environments. To test our hypothesis, we employed a change detection task in which participants were asked to indicate whether multisource auditory scenes were identical or different. Participants were better at detecting changes at the presence of an emotionally negative environment compared to neutral environment. Further, we found that participants were better at detecting changes of emotionally negative targets compared to neutral targets. Our results demonstrate that detecting changes in auditory scenes is influenced by emotion. The findings are discussed in the light of the theories of auditory attention, emotional modulation of attention, and the adaptive function of emotion for perception

The influence of meaning on noise annoyance from varied spectral

Spectral balance (the relation between high and low frequencies) is an auditory metric thatcorrelates with annoyance. However, previous research has shown conflicting results whereincreased annoyance has been linked to both increased high frequency content [1] and lowfrequency content [2]. The aim of this research is to test the hypothesis that the informationcontent of the signal could be a contributing factor to this discrepancy. An experiment wasperformed where participants rated sounds with different spectral slopes (flat, 3.5 dB/oct, 5.5dB/oct and 7.5 dB/oct) and different information content (varying from original recording of atruck sound to a noise spectrum). The results showed that different spectral slopes werepreferred for different levels of information content