Ordinal Pattern Analysis: A Tutorial on Assessing the Fit of Hypotheses to Individual Repeated Measures Data.

PURPOSE: This article provides a tutorial introduction to ordinal pattern analysis, a statistical analysis method designed to quantify the extent to which hypotheses of relative change across experimental conditions match observed data at the level of individuals. This method may be a useful addition to familiar parametric statistical methods including repeated measures analysis of variance and generalized linear mixed-effects models, particularly when analyzing inherently individual characteristics, such as perceptual processes, and where experimental effects are usefully modeled in relative rather than absolute terms. METHOD: Three analyses of increasing complexity are demonstrated using ordinal pattern analysis. An initial analysis of a very small data set is designed to explicate the simple mathematical calculations that make up ordinal pattern analysis, which can be performed without the aid of a computer. Analyses of slightly larger data sets are used to demonstrate familiar concepts, including comparison of competing hypotheses, handling missing data, group comparisons, and pairwise tests. All analyses can be reproduced using provided code and data. RESULTS: Ordinal pattern analysis results are presented, along with an analogous linear mixed-effects analysis, to illustrate the similarities and differences in information provided by ordinal pattern analysis in comparison to familiar parametric methods. CONCLUSION: Although ordinal pattern analysis does not produce familiar numerical effect sizes, it does provide highly interpretable results in terms of the proportion of individuals whose results are consistent with a hypothesis, along with individual and group-level statistics, which quantify hypothesis performance.

Is speech intelligibility what speech intelligibility tests test?

Natural, conversational speech signals contain sources of symbolic and iconic information, both of which are necessary for the full understanding of speech. But speech intelligibility tests, which are generally derived from written language, present only symbolic information sources, including lexical semantics and syntactic structures. Speech intelligibility tests exclude almost all sources of information about talkers, including their communicative intentions and their cognitive states and processes. There is no reason to suspect that either hearing impairment or noise selectively affect perception of only symbolic information. We must therefore conclude that diagnosis of good or poor speech intelligibility on the basis of standard speech tests is based on measurement of only a fraction of the task of speech perception. This paper presents a descriptive comparison of information sources present in three widely used speech intelligibility tests and spontaneous, conversational speech elicited using a referential communication task. The aim of this comparison is to draw attention to the differences in not just the signals, but the tasks of listeners perceiving these different speech signals and to highlight the implications of these differences for the interpretation and generalizability of speech intelligibility test results.

Measuring Speech Intelligibility and Hearing-Aid Benefit Using Everyday Conversational Sentences in Real-World Environments.

Laboratory and clinical-based assessments of speech intelligibility must evolve to better predict real-world speech intelligibility. One way of approaching this goal is to develop speech intelligibility tasks that are more representative of everyday speech communication outside the laboratory. Here, we evaluate speech intelligibility using both a standard sentence recall task based on clear, read speech (BKB sentences), and a sentence recall task consisting of spontaneously produced speech excised from conversations which took place in realistic background noises (ECO-SiN sentences). The sentences were embedded at natural speaking levels in six realistic background noises that differed in their overall level, which resulted in a range of fixed signal-to-noise ratios. Ten young, normal hearing participants took part in the study, along with 20 older participants with a range of levels of hearing loss who were tested with and without hearing-aid amplification. We found that scores were driven by hearing loss and the characteristics of the background noise, as expected, but also strongly by the speech materials. Scores obtained with the more realistic sentences were generally lower than those obtained with the standard sentences, which reduced ceiling effects for the majority of environments/listeners (but introduced floor effects in some cases). Because ceiling and floor effects limit the potential for observing changes in performance, benefits of amplification were highly dependent on the speech materials for a given background noise and participant group. Overall, the more realistic speech task offered a better dynamic range for capturing individual performance and hearing-aid benefit across the range of real-world environments we examined.

On Perspective Taking in Conversation and in Research: A Comment on Bambara et al. (2021).

PURPOSE: The purpose of this letter is to draw attention to recent literature regarding the communication abilities and experiences of Autistic people and the potential for detrimental effects on mental health and service provision resulting from behavior modification programs. I will argue that viewing Autistic communication as characterized by pragmatic language impairment is inconsistent with evidence of effective and positive communication between Autistic people and with the social model of disability. CONCLUSION: Proposals for interventions targeting Autistic people should carefully weigh the costs and benefits for Autistic people and should integrate the perspectives of Autistic people.

Ecological Validity, External Validity, and Mundane Realism in Hearing Science.

Tests of hearing function are typically conducted in conditions very different from those in which people need to hear and communicate. Even when test conditions are more similar, they cannot represent the diversity of situations that may be encountered by individuals in daily life. As a consequence, it is necessary to consider external validity: the extent to which findings are likely to generalize to conditions beyond those in which data are collected. External validity has long been a concern in many fields and has led to the development of theories and methods aimed at improving generalizability of laboratory findings. Within hearing science, along with related fields, efforts to address generalizability have come to focus heavily on realism: the extent to which laboratory conditions are similar to conditions found in everyday settings of interest. In fact, it seems that realism is now tacitly equated with generalizability. The term that has recently been applied to this approach by many researchers is ecological validity . Recent usage of the term ecological validity within hearing science, as well as other fields, is problematic for three related reasons: (i) it encourages the conflation of the separate concepts of realism and validity; (ii) it diverts attention from the need for methods of quantifying generalization directly; and (iii) it masks a useful longstanding definition of ecological validity within the field of ecological psychology. The definition of ecological validity first used within ecological psychology-the correlation between cues received at the peripheral nervous system and the identity of distant objects or events in the environment-is entirely different from its current usage in hearing science and many related fields. However, as part of an experimental approach known as representative design , the original concept of ecological validity can play a valuable role in facilitating generalizability. This paper will argue that separate existing terms should be used when referring to realism and generalizability, and that the definition of ecological validity provided by the Lens Model may be a valuable conceptual tool within hearing science.

Development of the Everyday Conversational Sentences in Noise test.

To capture the demands of real-world listening, laboratory-based speech-in-noise tasks must better reflect the types of speech and environments listeners encounter in everyday life. This article reports the development of original sentence materials that were produced spontaneously with varying vocal efforts. These sentences were extracted from conversations between a talker pair (female/male) communicating in different realistic acoustic environments to elicit normal, raised and loud vocal efforts. In total, 384 sentences were extracted to provide four equivalent lists of 16 sentences at the three efforts for the two talkers. The sentences were presented to 32 young, normally hearing participants in stationary noise at five signal-to-noise ratios from -8 to 0 dB in 2 dB steps. Psychometric functions were fitted for each sentence, revealing an average 50% speech reception threshold (SRT50) of -5.2 dB, and an average slope of 17.2%/dB. Sentences were then level-normalised to adjust their individual SRT50 to the mean (-5.2 dB). The sentences may be combined with realistic background noise to provide an assessment method that better captures the perceptual demands of everyday communication.

Hearing Aid Amplification Reduces Communication Effort of People With Hearing Impairment and Their Conversation Partners.

Objectives This study investigates the hypothesis that hearing aid amplification reduces effort within conversation for both hearing aid wearers and their communication partners. Levels of effort, in the form of speech production modifications, required to maintain successful spoken communication in a range of acoustic environments are compared to earlier reported results measured in unaided conversation conditions. Design Fifteen young adult normal-hearing participants and 15 older adult hearing-impaired participants were tested in pairs. Each pair consisted of one young normal-hearing participant and one older hearing-impaired participant. Hearing-impaired participants received directional hearing aid amplification, according to their audiogram, via a master hearing aid with gain provided according to the NAL-NL2 fitting formula. Pairs of participants were required to take part in naturalistic conversations through the use of a referential communication task. Each pair took part in five conversations, each of 5-min duration. During each conversation, participants were exposed to one of five different realistic acoustic environments presented through highly open headphones. The ordering of acoustic environments across experimental blocks was pseudorandomized. Resulting recordings of conversational speech were analyzed to determine the magnitude of speech modifications, in terms of vocal level and spectrum, produced by normal-hearing talkers as a function of both acoustic environment and the degree of high-frequency average hearing impairment of their conversation partner. Results The magnitude of spectral modifications of speech produced by normal-hearing talkers during conversations with aided hearing-impaired interlocutors was smaller than the speech modifications observed during conversations between the same pairs of participants in the absence of hearing aid amplification. Conclusions The provision of hearing aid amplification reduces the effort required to maintain communication in adverse conditions. This reduction in effort provides benefit to hearing-impaired individuals and also to the conversation partners of hearing-impaired individuals. By considering the impact of amplification on both sides of dyadic conversations, this approach contributes to an increased understanding of the likely impact of hearing impairment on everyday communication.

Hearing Impairment Increases Communication Effort During Conversations in Noise.

Purpose This article describes patterns of speech modifications produced by talkers as a function of the degree of hearing impairment of communication partners during naturalistic conversations in noise. An explanation of observed speech modifications is proposed in terms of a generalization of the concept of effort. This account complements existing theories of listening effort by extending the concept of effort to the domain of interactive communication. Method Twenty young adult normal hearing participants and 20 older adult hearing-impaired participants were tested in pairs. Each pair consisted of 1 young normal hearing participant and 1 older hearing-impaired participant. Pairs of participants took part in naturalistic conversations through the use of a referential communication task. Each pair completed a 5-min conversation in each of 5 different realistic acoustic environments. Results Talkers modified their speech, in terms of level and spectrum, in a gradient manner reflecting both the acoustic environment and the degree of hearing impairment of their conversation partner. All pairs of participants were able to maintain communication across all acoustic environments regardless of degree of hearing impairment and the level of environmental noise. Contrasting effects of noise and hearing impairment on speech production revealed distinct patterns of speech modifications produced by normal hearing and hearing-impaired talkers during conversation. This may reflect the fact that only the speech modifications produced by normal hearing talkers functioned to compensate for the hearing impairment of a conversation partner. Conclusions The data presented support the concept of communication effort as a dynamic feedback system between conversation participants. Additionally, these results provide insight into the nature of realistic speech signals, which are encountered by people with hearing impairment in everyday communication scenarios.

Eliciting Naturalistic Conversations: A Method for Assessing Communication Ability, Subjective Experience, and the Impacts of Noise and Hearing Impairment.

Purpose The purpose of this study was to introduce a method of eliciting conversational behavior with many aspects of realism, which may be used to study the impacts of hearing impairment and noise on verbal communication; to describe the characteristics of speech and language participants produced during the task; and to assess participants' engagement and motivation while completing the task. Method Twenty young adults with normal hearing and 20 older adults with hearing impairment took part in face-to-face conversations while completing a referential communication puzzle task designed to elicit natural conversational speech production and language with a number of realistic characteristics. Participants rated the difficulty and relevance of acoustic scenes for communication and their engagement in conversations. Results The communication task elicited speech production in a natural conversational register and language with many realistic characteristics, including complex linguistic constructions and typical disfluencies found in everyday speech, and approximately balanced contributions within dyads. Subjective ratings suggest that the task is robust to learning and fatigue effects and that participants remained highly engaged throughout the experiment. All participants were able to maintain successful communication regardless of background noise level and degree of hearing impairment. Conclusions The communication task described here may be used as part of a functional assessment of the ability to communicate in the presence of noise and hearing impairment. Although existing speech assessments have many strengths, they do not take into account the inherently interactive nature of spoken communication or the effects of motivation and engagement.