A sound effect: Exploration of the distinctiveness advantage in voice recognition

Two experiments are presented, which explore the presence of a distinctiveness advantage when recognising unfamiliar voices. In Experiment 1, distinctive voices were recognised significantly better, and with greater confidence, in a sequential same/different matching task compared with typical voices. These effects were replicated and extended in Experiment 2, as distinctive voices were recognised better even under challenging listening conditions imposed by nonsense sentences and temporal reversal. Taken together, the results aligned well with similar results when processing faces, and provided a useful point of comparison between voice and face processing.     

Identifiability of vowels and speakers from whispered syllables

In the present experiments, the effect of whisper register on speech perception was measured. We assessed listeners' abilities to identify 10 vowels in [hVd] context pronounced by 3 male and 3 female speakers in normal and whisper registers. Results showed 82% average identification accuracy in whisper mode, approximately a 10% falloff in identification accuracy from normally phonated speech. In both modes, significant confusions of [o] for [a] occurred, with some additional significant confusions occurring in whisper mode among vowels adjacent in F1/F2 space. We also assessed listeners' abilities to match whispered syllables with normally phonated ones by the same speaker. Each trial contained the matching syllable and two foils whispered by speakers of the same sex as the speaker of the target. Identification performance was significantly better than chance across subjects, speakers, and vowels, with no listener achieving better than 96% performance. Acoustic analyses measured potential cues to speaker identity independent of register.     

Does face familiarity influence speechreadability?

The impact of face familiarity on the speechreadability of faces is examined. First we measured the baseline speechreading performance of participants, from unfamiliar faces. Next, participants were familiarized with the face and voice of either the same or a different speaker, or were asked to take part in a word puzzle instead. Speechreading performance was measured again, before participants completed a further period of familiarization (or puzzle completion) and a final speechreading performance task. Results showed that speechreading performance increased overall with practice but that performance increased significantly more as participants became increasingly familiar with the same speaker. Our findings demonstrate the importance of talker-specific variations or other instance-based characteristics and suggest that these are a useful source of information for speechreading.     

Does face familiarity influence speechreadability?

The impact of face familiarity on the speechreadability of faces is examined. First we measured the baseline speechreading performance of participants, from unfamiliar faces. Next, participants were familiarized with the face and voice of either the same or a different speaker, or were asked to take part in a word puzzle instead. Speechreading performance was measured again, before participants completed a further period of familiarization (or puzzle completion) and a final speechreading performance task. Results showed that speechreading performance increased overall with practice but that performance increased significantly more as participants became increasingly familiar with the same speaker. Our findings demonstrate the importance of talker-specific variations or other instance-based characteristics and suggest that these are a useful source of information for speechreading.     

Knowing what to look for: Voice affects face race judgements

The study examined the effect that auditory information (speaker language/accent: Japanese or French) had on the processing of visual information (the speaker's race: Asian or Caucasian) in two forced-choice tasks: Classification and perceptual judgement on animated talking characters. Two (male and female) sets of facial morphs were constructed such that a 3-D head of Caucasian appearance was gradually morphed (in 11 steps) into one of Asian appearance. Each facial morph was animated in association with spoken French/Japanese or English with a French/Japanese accent. To examine the auditory effect, each animation was played with or without sound. Experiment 1 used an Asian or Caucasian classification task. Results showed that faces heard in conjunction with Japanese or a Japanese accent were more likely to be classified as Asian compared to those presented without sound. Experiment 2 used a same or different judgement task. Results showed that accuracy was improved by hearing a Japanese accent compared to without sound. These results were discussed in terms of the voice information acting as a cue to assist in organizing and attending to face features.     

A "voice inversion effect?"

Voice is the carrier of speech but is also an "auditory face" rich in information on the speaker's identity and affective state. Three experiments explored the possibility of a "voice inversion effect," by analogy to the classical "face inversion effect," which could support the hypothesis of a voice-specific module. Experiment 1 consisted of a gender identification task on two syllables pronounced by 90 speakers (boys, girls, men, and women). Experiment 2 consisted of a speaker discrimination task on pairs of syllables (8 men and 8 women). Experiment 3 consisted of an instrument discrimination task on pairs of melodies (8 string and 8 wind instruments). In all three experiments, stimuli were presented in 4 conditions: (1) no inversion; (2) temporal inversion (e.g., backwards speech); (3) frequency inversion centered around 4000 Hz; and (4) around 2500 Hz. Results indicated a significant decrease in performance caused by sound inversion, with a much stronger effect for frequency than for temporal inversion. Interestingly, although frequency inversion markedly affected timbre for both voices and instruments, subjects' performance was still above chance. However, performance at instrument discrimination was much higher than for voices, preventing comparison of inversion effects for voices vs. non-vocal stimuli. Additional experiments will be necessary to conclude on the existence of a possible "voice inversion effect."     

‘Please sort these voice recordings into 2 identities’: Effects of task instructions on performance in voice sorting studies

We investigated the effects of two types of task instructions on performance on a voice sorting task by listeners who were either familiar or unfamiliar with the voices. Listeners were asked to sort 15 naturally varying stimuli from two voice identities into perceived identities. Half of the listeners sorted the recordings freely into as many identities as they perceived; the other half were forced to sort stimuli into two identities only. As reported in previous studies, unfamiliar listeners formed more clusters than familiar listeners. Listeners therefore perceived different naturally varying stimuli from the same identity as coming from different identities, while being highly accurate at telling apart the stimuli from different voices. We further show that a change in task instructions – forcing listeners to sort stimuli into two identities only – helped unfamiliar listeners to overcome this selective failure at ‘telling people together’. This improvement, however, came at the cost of an increase in errors in telling people apart. For familiar listeners, similar non-significant trends were apparent. Therefore, even when informed about correct number of identities, listeners may fail to accurately perceive identity further highlighting that voice identity perception in the context of natural within-person variability is a challenging task. We discuss our results in terms of similarities and differences to findings in the face perception literature and their importance in applied settings, such as forensic voice identification.     

Effects of imagining speakers’ voices on the retention of words presented visually

Subjects were introduced to one male and one female voice by a tape recording with instructions to attend to characteristics of the voices. Then 18 pairs of words were presented visually on slides. The subject’s task during each 10-sec interslide interval was to repeat silently the pair of words over and over again in the male voice, in the female voice, or in the subject’s own voice. A surprise recognition test for the words indicated that the words were more likely to be recognized if they were spoken in the same Voice at test as was used to repeat them during presentation. Recognition of the words repeated in the subject’s own voice was not affected by the sex of the speaker at test. In Experiment 2, different speakers were used at test than those used by the subjects to repeat the words. The interaction between the sex of voice used at encoding and at test was again significant, but recognition was generally lower than in Experiment 1. It was concluded that it is not necessary to assume that subjects have literal copies of spoken words in memory but speaker’s voice does form an integral part of the verbal memory code and its influence is specific to a given speaker as well as to a given class of speakers (male or female).     

The effect of familiarity on within-person age judgements from voices

Listeners can perceive a person’s age from their voice with above chance accuracy. Studies have usually established this by asking listeners to directly estimate the age of unfamiliar voices. The recordings used mostly include cross-sectional samples of voices, including people of different ages to cover the age range of interest. Such cross-sectional samples likely include not only cues to age in the sound of the voice but also socio-phonetic cues, encoded in how a person speaks. How age perpcetion accuracy is affected when minimizing socio-phonetic cues by sampling the same voice at different time points remains largely unknown. Similarly, with the voices in age perception studies being usually unfamiliar to listeners, it is unclear how familiarity with a voice affects age perception. We asked listeners who were either familiar or unfamiliar with a set of four voices to complete an age discrimination task: listeners heard two recordings of the same person’s voice, recorded 15 years apart, and were asked to indicate in which recording the person was younger. Accuracy for both familiar and unfamiliar listeners was above chance. While familiarity advantages were apparent, accuracy was not particularly high: familiar and unfamiliar listeners were correct for 68.2% and 62.7% of trials, respectively (chance = 50%). Familiarity furthermore interacted with the voices included. Overall, our findings indicate that age perception from voices is not a trivial task at all times – even when listeners are familiar with a voice. We discuss our findings in the light of how reliable voice may be as a signal for age.     

Effects of vowel variety and sample lenght on identification of a speaker in a line-up

Subjects (average age 21 years, recruited by personal contact and through a school) were presented with a spoken sentence on tape and then heard six speakers of the same sex, including the original speaker, say the same sentence. They were required to indicate which was the original speaker. The task was repeated with seven different sentences and sets of speakers. One group of subjects heard short sentences containing an average of 2.14 different vowel sounds and 6.28 syllables, another group heard short sentences containing an average of 6.14 vowel sounds (7.28 syllables) and a third group heard longer sentences containing an average of 6.28 vowel sounds (11.00 syllables). Accuracy of speaker identification improved significantly when more vowel sounds were heard, but increased sentence length had no significant effect on performance. Performance was significantly better when the listener was the same sex as the speaker than when the listener was of the other sex.     

How many voices did you hear? Natural variability disrupts identity perception from unfamiliar voices

Our voices sound different depending on the context (laughing vs. talking to a child vs. giving a speech), making within‐person variability an inherent feature of human voices. When perceiving speaker identities, listeners therefore need to not only ‘tell people apart’ (perceiving exemplars from two different speakers as separate identities) but also ‘tell people together’ (perceiving different exemplars from the same speaker as a single identity). In the current study, we investigated how such natural within‐person variability affects voice identity perception. Using voices from a popular TV show, listeners, who were either familiar or unfamiliar with this show, sorted naturally varying voice clips from two speakers into clusters to represent perceived identities. Across three independent participant samples, unfamiliar listeners perceived more identities than familiar listeners and frequently mistook exemplars from the same speaker to be different identities. These findings point towards a selective failure in ‘telling people together’. Our study highlights within‐person variability as a key feature of voices that has striking effects on (unfamiliar) voice identity perception. Our findings not only open up a new line of enquiry in the field of voice perception but also call for a re‐evaluation of theoretical models to account for natural variability during identity perception.     

嗓音源判断过程中的范畴效应和通道效应

该项研究通过设计4种实验条件,旨在探讨不同嗓音词的再认和嗓音判断过程各自的特点及其相互联系。4种实验条件是由2种诵读方式和2种测试方式组合而成,2种诵读方式为同范畴同嗓音和同范畴异嗓音,2种测试方式为视觉呈现和听觉呈现。52名大学生被试随机分成4个独立的组,分别接受一种实验处理。实验结果显示：(1)同范畴同嗓音条件与同范畴异嗓音条件相比,前者项目词的嗓音源判断效果好。提示增加相同记忆源项目间语义联系将有利于记忆源的检测判断。(2)项目再认与项目嗓音判断结果不完全一致,只有在诵读方式为同范畴同嗓音测试方式为听觉呈现情境下,两者有较高的正相关。(3)在同范畴同嗓音诵读条件下,再认反映出学习和测试通道源一致性优势效应,嗓音判断没有反映出通道源一致性优势效应。     

Perceptual prioritization of self-associated voices

Information associated with the self is prioritized relative to information associated with others and is therefore processed more quickly and accurately. Across three experiments, we examined whether a new externally-generated voice could become associated with the self and thus be prioritized in perception. In the first experiment, participants learned associations between three unfamiliar voices and three identities (self, friend, stranger). Participants then made speeded judgements of whether voice-identity pairs were correctly matched, or not. A clear self-prioritization effect was found, with participants showing quicker and more accurate responses to the newly self-associated voice relative to either the friend- or stranger- voice. In two further experiments, we tested whether this prioritization effect increased if the self-voice was gender-matched to the identity of the participant (Experiment 2) or if the self-voice was chosen by the participant (Experiment 3). Gender-matching did not significantly influence prioritization; the self-voice was similarly prioritized when it matched the gender identity of the listener as when it did not. However, we observed that choosing the self-voice did interact with prioritization (Experiment 3); the self-voice became more prominent, via lesser prioritization of the other identities, when the self-voice was chosen relative to when it was not. Our findings have implications for the design and selection of individuated synthetic voices used for assistive communication devices, suggesting that agency in choosing a new vocal identity may modulate the distinctiveness of that voice relative to others.     

Performance on a face perception task is associated with empathy quotient scores, but not systemizing scores or participant sex

This preliminary study investigated whether individual differences in performance on a difficult social perception task (determining the sex of shape normalized, line drawn dynamic faces) are related to sex of observer, scores on an empathy quotient and scores on a systemizing quotient. Performance in the face perception task (N = 60) was above chance, indicating that participants could judge the sex of the degraded facial stimuli from dynamic information alone. There was a trend for women to be more accurate in their judgments of target sex than men, but regression analyses indicated that EQ scores alone predicted performance on the task. This study suggests that empathy may mediate sex differences in face perception abilities, and potentially other tasks in social perception.     

从征求到反应：建言行为链中的管理者角色

在建言行为发生链中,管理者扮演着征求者和反应者的不同角色。在管理实践中,管理者却罕于从员工处征求建言,或未能对员工建言做出有效反应。在学术界,目前有关管理者征求建言、纳谏和建言/建言者评估的研究日益丰富,但不成系统。为解决这些实践和理论上的不足,提出并整合建言行为链框架;并基于输入-过程-输出模型,从管理者角色入手,系统分析和归纳管理者征求建言、采纳建言、评估建言(者)的前提和结果,以诠释管理者在员工建言行为链中发挥的作用及其机制,并为管理者更好履行建言管理职能提供实践参考。     

建言类型对领导者建言采纳的影响：面子与幽默的作用

以说服和面子理论为基础,通过两个研究探讨领导者建言采纳行为的影响因素及作用机制。结果发现：相对于促进型建言,抑制型建言给领导带来的面子威胁更大,且领导者感知面子威胁在建言类型与建言采纳之间起部分的中介作用。而幽默类型与水平影响领导者感知面子威胁的程度,积极幽默水平越高,领导者感知面子威胁的程度越低,其建言采纳可能性越高。这表明领导者感知面子威胁在建言类型与建议采纳间起中介作用,幽默调节了此中介效应。     

Performance on a face perception task is associated with empathy quotient scores,but not systemizing scores or participant sex

This preliminary study investigated whether individual differences in performance on a difficult social perception task (determining the sex of shape normalized, line drawn dynamic faces) are related to sex of observer, scores on an empathy quotient and scores on a systemizing quotient. Performance in the face perception task (N = 60) was above chance, indicating that participants could judge the sex of the degraded facial stimuli from dynamic information alone. There was a trend for women to be more accurate in their judgments of target sex than men, but regression analyses indicated that EQ scores alone predicted performance on the task. This study suggests that empathy may mediate sex differences in face perception abilities, and potentially other tasks in social perception.     

Famous face recognition,face matching,and extraversion

It has been previously established that extraverts who are skilled at interpersonal interaction perform significantly better than introverts on a face-specific recognition memory task. In our experiment we further investigate the relationship between extraversion and face recognition, focusing on famous face recognition and face matching. Results indicate that more extraverted individuals perform significantly better on an upright famous face recognition task and show significantly larger face inversion effects. However, our results did not find an effect of extraversion on face matching or inverted famous face recognition.     

Individual differences in face and voice matching abilities: The relationship between accuracy and consistency

Deciding whether two different face photographs or voice samples are from the same person represent fundamental challenges within applied settings. To date, most research has focussed on average performance in these tests, failing to consider individual differences and within‐person consistency in responses. Here, participants completed the same face (Experiment 1) or voice matching test (Experiment 2) on two separate occasions, allowing comparison of overall accuracy across the two timepoints as well as consistency in trial‐level responses. In both experiments, participants were highly consistent in their performances. In addition, we demonstrated a large association between consistency and accuracy, with the most accurate participants also tending to be the most consistent. This is an important result for applied settings in which organisational groups of super‐matchers are deployed in real‐world contexts. Being able to reliably identify these high performers based upon only a single test informs regarding recruitment for law enforcement agencies worldwide.     

Hearing a face: cross-modal speaker matching using isolated visible speech

An experiment was performed to test whether cross-modal speaker matches could be made using isolated visible speech movement information. Visible speech movements were isolated using a point-light technique. In five conditions, subjects were asked to match a voice to one of two (unimodal) speaking point-light faces on the basis of speaker identity. Two of these conditions were designed to maintain the idiosyncratic speech dynamics of the speakers, whereas three of the conditions deleted or distorted the dynamics in various ways. Some of these conditions also equated video frames across dynamically correct and distorted movements. The results revealed generally better matching performance in the conditions that maintained the correct speech dynamics than in those conditions that did not, despite containing exactly the same video frames. The results suggest that visible speech movements themselves can support cross-modal speaker matching.