Examining Gesture Production in the Presence of Communication Challenges

Laura M. Morett

doi:10.3791/66256

JoVE Journal > Behavior

Davranış

Examining Gesture Production in the Presence of Communication Challenges

Published: January 26, 2024

doi:

10.3791/66256

Laura M. Morett¹

¹Department of Speech, Language, and Hearing Sciences,University of Missouri

Özet

Here, we present a protocol that manipulates interlocutor visibility to examine its impact on gesture production in interpersonal communication. This protocol is flexible to tasks implemented, gestures examined, and communication modality. It is ideal for populations with communication challenges, such as second language learners and individuals with autism spectrum disorder.

Abstract

Understanding why speakers modify their co-speech hand gestures when speaking to interlocutors provides valuable insight into how these gestures contribute to interpersonal communication in face-to-face and virtual contexts. The current protocols manipulate the visibility of speakers and their interlocutors in tandem in a face-to-face context to examine the impact of visibility on gesture production when communication is challenging. In these protocols, speakers complete tasks such as teaching words from an unfamiliar second language or recounting the events of cartoon vignettes to an interlocutor who is either another participant or a confederate. When performing these tasks, speakers are visible or non-visible to their interlocutor, and the speaker is visible or non-visible to the participant. In the word learning task, speakers and interlocutors visible to one another produce more representational gestures, which convey meaning via handshape and motion, and deictic (pointing) gestures than speakers and interlocutors who are not visible to one another. In the narrative retelling protocol, adolescents with autism spectrum disorder (ASD) produced more gestures when speaking to visible interlocutors than non-visible interlocutors. A major strength of the current protocol is its flexibility in terms of the tasks, populations, and gestures examined, and the current protocol can be implemented in videoconferencing as well as face-to-face contexts. Thus, the current protocol has the potential to advance the understanding of gesture production by elucidating its role in interpersonal communication in populations with communication challenges.

Introduction

Co-speech gestures (heretofore, gestures) – meaningful hand movements produced concurrently with speech – contribute to interpersonal communication by conveying information complementing verbal content¹. According to the most widely used taxonomy²^,³, gestures can be divided into three categories: representational gestures, which convey referents via their form and motion (e.g., flapping the hands back and forth together to convey flying); beat gestures, which convey emphasis via simple punctate movements (e.g., moving the dominant hand downward slightly in conjunction with each word in the phrase "right now"); and deictic gestures, which draw attention to the presence or absence of an entity via pointing (e.g., swinging the thumb backward to indicate something behind oneself). Representational gestures can be further divided into two additional categories: iconic gestures, which convey concrete referents (e.g., a bird), and metaphorical gestures, which convey metaphorical referents (e.g., ecstasy). Because gesture and speech arise from the same conceptual content, they are closely related in meaning⁴^,⁵. By serving as an iconic visual medium for communication, gestures can help compensate when challenges in spoken language comprehension arise⁶, whether due to individual factors such as limited proficiency in the language spoken⁷^,⁸ or environmental factors such as difficulty in hearing speech⁹^,¹⁰. Thus, gestures are integral to understanding interpersonal communication in face-to-face and virtual contexts, providing insight into how speakers and listeners convey and comprehend information multimodally.

Several structured interactive tasks have been developed to measure how gesture affects interpersonal communication. These tasks include interviews, in which participants respond to questions by describing their personal experiences¹¹^,¹²; image description, in which a static image is presented to participants to describe¹³^,¹⁴; puzzle solving, in which participants describe how to solve a puzzle by spatially orienting components correctly¹⁵^,¹⁶; direction provision, in which participants are instructed to give directions to a location unfamiliar to listeners¹⁷^,¹⁸^,¹⁹; and narrative retelling, in which participants view a cartoon depicting a sequence of events and subsequently recount them²⁰^,²¹^,²². Many of the tasks employed in the studies cited above incorporate spatial content and action, which gesture conveys with particular efficacy¹⁵^,²³^,²⁴^,²⁵. In the tasks for the studies cited above, participants typically produce gestures in conjunction with language, and information conveyed via gesture and its relationship to concurrently produced language is assessed. Alternatively, participants may view a recording of someone gesturing (or not gesturing) and producing language when completing one of these tasks, after which participants' comprehension is assessed. All of these tasks may be conducted virtually as well as face-to-face, enabling data collection from a wide range of participants and comparison across modalities.

The impact of gestures on interpersonal communication has been implemented with a wide range of participants. Of particular interest have been populations with communication challenges, including young children²⁶^,²⁷^,²⁸^,²⁹^,³⁰, second language (L2) users⁸^,³¹^,³²^,³³, individuals with autism spectrum disorder (ASD)²⁰^,²¹^,²²^,³⁴, individuals with specific language impairment³⁵^,³⁶^,³⁷, individuals with aphasia¹²^,³⁸, individuals with brain injury³⁹, and individuals who stutter⁴⁰^,⁴¹. This work has revealed that, while many of these populations can utilize gestures to facilitate communication, some, such as individuals with autism spectrum disorder, may encounter difficulty leveraging gestures to communicate effectively. The findings suggest that this may be due to the extent to which these populations take audience design and environmental cues into consideration, highlighting the practical implications of these explanations for the impact of gestures on communication.

A key feature providing insight into the impact of gestures on interpersonal communication is interlocutor visibility. A question of great importance in the field of gesture research is the extent to which participants gesture for their own benefit, indicating the offloading of cognitive operations onto the body, vs. the benefit of their interlocutors, indicating the use of gesture to communicate. This question has been investigated by examining the impact of interlocutor (non-)visibility on gesture production in face-to-face contexts via the use of an opaque partition²⁶^,⁴², as well as in telephone contexts¹³ and virtual contexts⁴³. Overall, the results of this work indicate that, although speakers gesture for their own benefit, they produce more representational gestures when communicating with visible than non-visible interlocutors, whereas beat gesture production is similar regardless of interlocutor visibility. Thus, they suggest that representational gesture facilitates communication across a variety of contexts, suggesting that speakers take the perspective of their interlocutors into account and modify their gesture production accordingly. Although previous research examining the effect of interlocutor visibility has been instrumental in providing insight into the contributions of gesture to interpersonal communication, it has focused on English as a first language (L1) in typically developing populations, so it is unclear whether the findings can be extended to populations with communication challenges. Two such populations are L2 learners, who may struggle to communicate via speech in the target language, and children with ASD, whose verbal and nonverbal communication are abnormal. Furthermore, little research has examined the impact of interlocutor visibility on gesture production in virtual contexts, which allow the effect of the interlocutor's visibility on the participant to be disentangled from the effect of the participant's visibility to the interlocutor, so the replicability of findings from these contexts is currently unclear. Finally, some research has focused on the impact of interlocutor visibility on the production of specific types of gestures, so it is unclear whether the production of other types of gestures is similarly affected by interlocutor visibility.

The protocols described below manipulate interlocutor visibility to examine gesture production in challenging circumstances: L2 word learning and narrative retelling by individuals with ASD. The L2 word learning protocol bridges research examining the impact of observing gestures on L2 word learning with research examining the contribution of gestures to communication via an interactive word learning paradigm. In this paradigm, participants unfamiliar with the target language learn words in it and then teach these words to other participants unfamiliar with the target language, permitting the impact of interlocutor visibility on gesture production to be examined in the earliest stages of L2 acquisition in a conversational context. The cartoon retelling paradigm employs a widely used narrative retelling task in which differences in gesture production have been observed when interlocutor visibility is manipulated with a new population: adolescents with ASD. This population is of interest because language development, including gesture production, is mature by adolescence, and ASD entails difficulty with verbal and nonverbal communication, including gestures, as well as a lack of sensitivity to the communicative needs of interlocutors. Together, these protocols provide insight into the extent to which gesture production is dependent on – and, conversely, can compensate for – speech when interpersonal communication is challenging.

Based on findings demonstrating how listener visibility affects gesture production by L1 English speakers¹³^,²⁶^,⁴²^,⁴³, it was hypothesized that participants would produce more overall gestures and more representational gestures when discussing L2 words with a visible than a non-visible interlocutor. Based on findings demonstrating abnormalities in gesture production in ASD²⁰^,⁴⁴, it was hypothesized that adolescents with ASD would produce fewer overall gestures as well as fewer representational and deictic gestures than typically developing (TD) adolescents. Moreover, based on findings showing that ASD entails difficulty with perspective taking⁴⁵, it was hypothesized that gesture production by adolescents with ASD would not differ significantly in the presence of visible and non-visible interlocutors. Finally, an interaction between diagnosis and visibility was predicted, such that gesture production would not differ by visibility for adolescents with ASD but that it would for TD adolescents.

Protocol

All participants provided written consent, and all protocols were approved by the Institutional Review Boards at the host institution. The L2 word learning and cartoon retelling protocols were implemented in the studies on which the representative results are based²¹^,³³. Although these protocols have been conducted only in in-person contexts to date, a related protocol manipulating the visibility of the interlocutor and the participant independently not described here is currently being conducted to provide insight into replicability in this context, with plans to expand it to populations with communication challenges, such as individuals with ASD.

1. Participants

NOTE: While respecting necessary constraints on participant characteristics for each study, samples should be representative of the larger population insofar as possible.

Participant recruitment for L2 word learning protocol
1. Recruit participants aged 18 years and above with normal or corrected-to-normal vision and normal hearing who are L1 speakers of English. To ensure that the study examines the impact of gesture on initial-stage L2 word learning, recruit participants without any knowledge of Hungarian, the target language.
Participant recruitment for cartoon retelling protocol
1. Recruit participants of an age capable of completing the experimental task (10-20 years of age in Morett et al.²¹.) with a diagnosis of ASD or who are typically developing (TD).
  1. To ensure that participants can complete the experimental task successfully, recruit participants who are L1 speakers of English, have normal or corrected-to-normal vision and normal hearing, and have a full-scale IQ of 85 or above, as measured before or at the time of the study via a standardized assessment⁴⁶.
  2. To ensure that the study examines the specific effects of ASD on gesture production, recruit participants with ASD without epilepsy, meningitis, encephalitis, diabetes, childhood disintegrative disorder, or Pervasive developmental disorder-not otherwise specified (PDD-NOS).
  3. To ensure that gesture production in ASD can be compared to typical gesture production, recruit TD participants without comorbid psychiatric disorders or first-degree relatives diagnosed with pervasive developmental disorders.

2. Overview of visibility manipulation

Recruit participants in pairs if the effects of producing and observing spontaneous gestures will be examined, as in the L2 word learning protocol. Recruit participants individually in coordination with a research assistant acting as a participant if only the effects of producing spontaneous gestures will be examined, as in the cartoon retelling protocol.
Provide an informed consent form with information about the study to participants to sign and answer any questions about it, taking care not to reveal the focus of the study on gesture production. Collect the form after participants have signed it.
For participants recruited in pairs, use a selection method such as a coin toss to determine which participant will serve as the speaker, who will do most of the talking in the experimental task, and which participant will serve as the interlocutor, who will do most of the listening and occasionally interact with the speaker in the experimental task. For participants recruited individually with a research assistant acting as a participant, use a fixed selection method such as a rigged coin toss to ensure that the participant always serves as the speaker and that the research assistant always serves as the interlocutor.
In half of the experimental sessions, place an opaque divider between the speaker and the interlocutor to ensure they cannot see one another's face or hands.
Explain to participants what they will do in the experimental task and answer any questions about it. Inform participants that their speech will be audio recorded, pointing out the microphone used for this purpose. To avoid any effects of awareness of video recording on gesture production, do not inform participants that they will be video recorded and ensure that the video camera used for this purpose is not visible to participants.
Initiate video and audio recording by pressing the appropriate buttons. Implement the experimental task to elicit speech and gesture from the speaker and the participant interlocutor, if there is one.
If a within-participants design is employed, remove the opaque divider if used in the first iteration or place it between the speaker and interlocutor if not used in the first iteration.
Repeat the experimental task as needed until all stimuli have been exhausted.
Stop video and audio recording by pressing the appropriate buttons. Inform participants that the study focused on gestures and that they were video recorded and offer to delete their videos prior to data analysis if desired.
Answer any questions from participants and thank them for participating before dismissing them.

3. L2 word learning protocol

Video and audio record the speaker and interlocutor so that speech and gesture production during the experimental task can be analyzed later.
1. Place a table microphone between the speaker and the interlocutor for audio recording. Place a video camera to one side between the speaker and interlocutor at a 90° angle and ensure it is not visible to participants.
2. Additionally, ensure that both the speaker and interlocutor are encompassed within the scope of view of the video camera and that the computer screen is not visible in the scope of view of the video camera to maintain blindness to the condition in which L2 words are presented in the analysis.
Using a computer, present an L2 word from the target language aurally to the speaker via earphones to ensure that it is inaudible to the interlocutor so that the speaker can subsequently teach it to the interlocutor. At the same time, present either a video of an L1 speaker of the target language saying the L2 word and producing a representational gesture conveying its meaning with the text of the L2 word at the bottom of the screen or the L2 word as text in the middle of the screen without a video to the speaker.
After a 500 ms pause, present the L1 translation of the L2 word as text in the middle of the screen to the speaker for 2000 ms.
Prompt the explainer to teach the L2 word and its meaning to the interlocutor via speech and/or gesture.
Instruct the speaker to press a button to move on when ready. After the speaker does so, present another L2 word. Repeat this process until all 20 L2 words have been presented in random order.
Individually test the speaker's and interlocutor's knowledge of the L2 words presented in the experimental task by presenting each L2 word as text and prompting them to say its L1 translation or skip the word if they do not recall its translation.

4. Cartoon retelling protocol

If the participant's IQ has not been measured via a standardized IQ assessment previously, administer one to ensure that their IQ is 85 or above.
Video and audio record participants so that their speech and gesture production can be analyzed later. Place a table microphone in front of the participant for audio recording. Place a camera on one side of the participant at a 90° angle and ensure that the camera is not visible to the participant.
Present the first half of the Looney Tunes cartoon Canary Row to the participant. This half of the cartoon contains several vignettes in which Sylvester the cat attempts and fails to catch Tweety bird.
Instruct the participant to retell the events of the first half of the cartoon to the interlocutor in as much detail as they can recall. Instruct the interlocutor to listen to the participant's retelling, prompting the participant to say more if it is brief.
Repeat steps 4.1. and 4.2. for the second half of the Canary Row video, which contains several more vignettes in which Sylvester the cat attempts and fails to catch Tweety bird.

5. Transcription and coding

NOTE: To minimize bias, when possible, transcribe and code data blind without knowing which participants and trials were assigned to which conditions. Ideally, transcribers and coders should not be involved in data collection.

Transcribe all participant speech orthographically by hand using appropriate software according to a standardized scheme, such as CHAT⁴⁷, to produce a word count. Transcribe all verbal information, such as fillers and corrections, but do not transcribe pauses.
Identify and code all participant gestures to produce a count for each gesture type. Identify gestures from rest to rest and categorize them into four types based on McNeill's taxonomy²^,³: iconic, metaphorical, beat, and deictic. Note that some gestures may be classified as more than one type.
Compute the rate of gestures per hundred words by dividing the number of representational gestures by the number of words and multiplying it by 100 for each vignette.
Have an independent coder code participant gestures for 25% of the data. Compute percent agreement for data coded by both coders and ensure that it is at least 80% to ensure sufficient interrater reliability.

Representative Results

L2 word learning
Implementation: The results reported below are based on data collected from 52 healthy participants (21 males, 31 females; age: M = 20.15, SD = 1.73, range = 18-28) according to the protocol outlined above. All speech and gesture were coded by a primary coder, who could not be blind to visibility condition as data from both the speaker and interlocutor were recorded using a single camera, as described in step 3.4. To establish inter-rater reliability, a secondary coder independently coded all gestures produced by 6 randomly selected pairs (k = 389, 23.08% of the data). Agreement between the primary and secondary raters was 92% in identifying gestures and 90% for categorizing them.

Overview of analyses: In the following analyses, both speakers' and interlocutors' overall gesture production and production of different types of gestures were compared based on visibility to gauge their effect on the communication of L2 words. Due to the irregularity of normality and skewness, comparisons based on visibility were made using non-parametric Mann-Whitney U-tests, which do not have assumptions based on normality and skewness. More specifically, Mann-Whitney U tests were used to determine whether the probability of gesture production being greater in the visible condition than the non-visible condition was equal to the probability of gesture production being greater in the non-visible condition than the visible condition.

Findings: Mann-Whitney U tests revealed that primary speakers whose interlocutors were visible produced more gestures than primary speakers whose interlocutors were not visible, U = 53, p = .02. Specifically, primary speakers with visible interlocutors produced more representational, U = 30, p = 0.001, and deictic, U = 52, p = 0.02, gestures than primary speakers with non-visible interlocutors (see Figure 1). Primary speakers' beat gesture production did not differ significantly between visibility conditions, U = 82, n.s., though they produced more of these gestures in the presence of visible than non-visible interlocutors. Although interlocutors visible to primary speakers also produced more gestures than interlocutors not visible to primary speakers, this difference failed to reach significance, U = 89, n.s. None of the comparisons between different gesture types as a function of visibility reached significance for interlocutors, despite the fact that they produced more of every type of gesture in the presence of visible than non-visible primary speakers. These findings provide evidence that primary speakers increase their production of representational and deictic gestures in the presence of visible interlocutors, whereas their interlocutors may not.

Cartoon retelling results
Implementation: The results reported below are based on data collected from 41 adolescent participants, 18 of whom were diagnosed with ASD (15 males, 3 females; age: M = 15.17, SD = 2.75, range = 10.44 – 19.49) and 23 of whom were typically developing (15 males, 6 females; age: M = 15.81, SD = 2.42, range = 11.52-19.36). Participants in both groups were matched on chronological age, gender, and verbal IQ. All speech and gesture were coded by two coders blind to visibility condition and diagnosis. To establish inter-rater reliability, a secondary coder independently coded all gestures produced by 10 randomly selected participants (24.3% of the data). Agreement between the primary and secondary raters was 98% in identifying gestures and 95.4% for categorizing them.

Overview of analyses: In the following analyses, overall gesture production and production of different types of gestures were compared based on diagnosis and visibility to gauge their effects on communication. Specifically, two-way analyses of variance were employed to examine both independent and interactive effects of diagnosis (ASD vs. TD) and visibility (visible vs. non-visible).

Findings: For overall gesture production, there was no main effect of diagnosis (F < 1). However, we found an interaction of gesture type by diagnosis (F(3,117) = 0.74, p = 0.05, η_p² = 0.07). Specifically, adolescents with ASD produced fewer metaphorical gestures (M = 0.48; SD = 0.63), t(39) = 1.99, p = 0.05, d = 0.49 and beat gestures (M = 0.26; SD = 0.60, t(39) = 2.13, p = 0.04, d = 0.67) than TD adolescents (metaphorical: M = 1.08; SD = 1.62; beat: M = 1.14; SD = 1.76). No differences between ASD and TD adolescents were found for the production of iconic (ASD: M = 0.79; SD = 0.25; TD: M = 0.77; SD = 0.25; t < 1) or deictic (ASD: M = 0.36; SD = 0.16; TD: M = 0.25; SD = 0.10; t<1) gestures. Both ASD and TD adolescents produced more gestures when speaking to a visible listener (M = 0.97 g/100; SD = 1.45) than a non-visible listener (M = 0.36 g/100; SD = 0.83; F(1,39) = 18.18, p < 0.001, η_p²= 0.32; see Figure 2). However, overall gesture production did not show a diagnosis by interlocutor visibility interaction (F < 1). Taken together, these results indicate that adolescents with ASD produce different types of gestures than their TD peers, but adolescents with ASD increase their production of all types of gestures when speaking to visible interlocutors, like their TD peers.

Figure 1: Gesture production of primary speakers and interlocutors in L2 word learning task. Gesture production of primary speakers and interlocutors per hundred words by visibility condition (error bars represent standard error). Please click here to view a larger version of this figure.

Figure 2: Gesture production of ASD and TD adolescents by visibility in cartoon retelling task. Production of different gesture types per hundred words by ASD and TD adolescents in the (A) visible listener condition and (B) non-visible listener condition (error bars represent standard error). This figure has been modified with permission from Morett et al.²¹. Please click here to view a larger version of this figure.

Discussion

The current protocol manipulates the visibility of the speaker and interlocutor to one another, providing insight into its impact on gesture production under challenging circumstances: L2 word learning and narrative retelling by adolescents with ASD. This protocol can be implemented either in-person or virtually, permitting participant and interlocutor visibility to be manipulated in tandem or independently. It can accommodate a wide variety of experimental tasks, gestures, and populations, providing them with the flexibility to be implemented in various circumstances in which communication is challenging and to reveal numerous ways in which gesture production is altered within these circumstances. Thus, by manipulating interlocutor visibility, the current protocol provides insight into how gesture affects interpersonal communication in populations with communication challenges.

As in other similar protocols used with healthy adult L1 speakers¹³^,²⁶^,⁴²^,⁴³, the most critical aspect of the current protocol is the manipulation of the visibility of speakers and interlocutors to one another. Because the current protocol was conducted in person in both studies reported here²¹^,³³, visibility was manipulated in tandem, such that speakers and interlocutors were either mutually visible or non-visible to one another. The current protocol can easily be adapted for implementation in a videoconferencing context so that the visibility of the speaker and interlocutor can be manipulated independently, permitting the effects of visibility on gesture production by the speaker and interlocutor to be disentangled⁴³. Another critical aspect of the current protocol is its dialogic nature, which reflects naturalistic conversational contexts through the inclusion of both a speaker and an interlocutor, consistent with previous structured interactive tasks used to examine gesture production¹¹^,¹²^,¹⁷^,¹⁸^,¹⁹^,²⁰^,²². Notably, the interlocutor can be either a second participant or a research assistant, depending on whether their gesture production is of interest. A final critical aspect of the current protocol is not informing participants of its focus on gesture production and ensuring that they are unaware that they are video recorded until after the experimental task is complete²⁶^,⁴². Although participants have been aware of video recording in some studies using similar protocols¹²^,²⁰^,⁴³, gesture production in protocols such as the current protocol is more likely to approximate gesture production in naturalistic conversational settings when participants are unaware that their gestures are being recorded.

A major strength of the current protocol is its flexibility in terms of tasks, participants, and gestures. Although narrative retelling tasks are often used given their effectiveness in eliciting differences in representational gesture production in face-to-face contexts²⁶^,⁴², the manipulation can incorporate other tasks to elicit gesture production, such as the L2 word learning paradigm described here³³^,⁴⁸, as well as interviews¹¹^,¹², image description¹³^,¹⁴, puzzle solving¹⁵^,¹⁶, and direction provision¹⁷^,¹⁹^,²⁷. Due to its participant friendliness, the interlocutor visibility manipulation can be used with populations with communication challenges, such as L2 learners and children with autism spectrum disorder, as described here, as well as children and adults with specific language impairment, stuttering, brain injury, and aphasia. The interlocutor visibility manipulation permits the examination of representational, beat, and deictic gestures, allowing differences in their production by interlocutor visibility to be quantified across populations. Finally, although the interlocutor visibility manipulation was originally developed for use in a face-to-face context, it can be implemented in a videoconferencing context by turning the webcam on and off, permitting direct comparison of gesture production when visibility is manipulated in videoconferencing and face-to-face contexts⁴⁹, as well as independent examination of the effects of visibility of the primary speaker and interlocutor on gesture production⁴³.

Although interlocutor visibility manipulation has the potential to advance the understanding of gesture production in populations and circumstances with communication challenges due to its participant friendliness and flexibility, it has some limitations. In its current instantiation, it is implemented in person, which may limit recruitment to local convenience samples. This limitation has been overcome via implementation in a videoconferencing context, but to date, it has not been implemented with populations with communication challenges in a videoconferencing context, so the extent to which findings concerning gesture production in these populations replicates in these contexts is currently unclear. To address this limitation, we are currently implementing a version of the manipulation with the cartoon retelling task in a videoconferencing context with healthy L1 English speakers, which we plan to implement with individuals with ASD subsequently. Despite the accessibility of the visibility manipulation to a wide range of potential participants with communication challenges, participants must be able to complete the tasks successfully, making them inaccessible to participants lacking sufficient command of the language in which they are conducted to do so. Although this limitation may be addressable to some extent via task simplification, reducing speech production demands may reduce gesture production, making differences in gesture production more difficult to detect due to interlocutor visibility.

The current protocol represents the first implementation of the interlocutor visibility manipulation with populations with communication challenges. Although interlocutor visibility has previously been manipulated to examine its effect on gesture production in healthy young children²⁶, who may struggle to communicate in their L1 of English in some cases, they do not experience the degree and persistence of communication challenges that beginning L2 learners or adolescents with ASD do. Findings from the previously published studies discussed in the representative results section²¹^,³³ serve as a proof of concept that the current protocol can reveal similarities and differences in how interlocutor visibility affects gesture production in these populations, demonstrating that they can be implemented with individuals with greater and more persistent communication challenges than healthy L1 English speaking young children. In the future, it will be fruitful to implement the current protocol with populations with even greater and more persistent communication challenges, such as individuals with aphasia¹²^,³⁸, specific language impairment³⁵^,³⁶^,³⁷, or stuttering⁴⁰^,⁴¹ to examine the impact of manipulating interlocutor visibility on their gesture production.

Overall, the current protocols provide a means to examine the influence of interlocutor visibility on gesture production in the presence of communication challenges during L2 word learning and narrative retelling in individuals with ASD. In doing so, it provides insight into the extent to which the gesture production of individuals with communication challenges is responsive to interlocutor needs, revealing the extent to which the individuals with communication challenges engage in perspective taking during communication. Manipulation of interlocutor visibility provides the flexibility to examine this as well as other important theoretical questions concerning gesture production with various tasks, populations, and gesture types in virtual as well as face-to-face contexts, revealing the extent to which the results are generalizable and replicable and providing insight into situations in which individual differences in gesture production may be observed. Thus, manipulation of interlocutor visibility has the potential to advance the understanding of gesture production under challenging communicative circumstances in face-to-face and virtual contexts.

Açıklamalar

The authors have nothing to disclose.

Acknowledgements

Development and validation of the L2 word learning protocol was supported by a National Defense Science and Engineering Graduate (NDSEG) Fellowship (32 CFR 168a) issued by the US Department of Defense Air Force Office of Scientific Research. Development and validation of the cartoon retelling protocol with adolescents with ASD was supported by a Ruth S. Kirschstein Institutional National Research Service Award (T32) from the National Institutes of Mental Health. The author thanks Rachel Fader, Theo Haugen, Andrew Lynn, Ashlie Caputo, and Marco Pilotta with assistance with data collection and coding.

Materials

Computer	Apple	Z131	24" iMac, 8-core CPU & GPU, M3 chip
Conference USB microphone	Tonor	B07GVGMW59
ELAN	The Language Archive		Software application used to transcribe speech and gesture
Video Recorder	Vjianger	B07YBCMXJJ	FHD 2.7K 30 FPS 24 MP 16X digital zoom 3" touch screen video recorder with renote control and tripod
Weschler Abbreviated Scale of Intelligence	Pearson	158981561	Used to verify full scale IQ ≥ 80 in Morett et al. (2016)