The use and function of gestures in word-finding difficulties in aphasia

Background: Gestures are spontaneous hand and arm movements that are part of everyday communication. The roles of gestures in communication are disputed. Most agree that they augment the information conveyed in speech. More contentiously, some argue that they facilitate speech, particularly when word-finding difficulties (WFD) occur. Exploring gestures in aphasia may further illuminate their role. Aims: This study explored the spontaneous use of gestures in the conversation of participants with aphasia (PWA) and neurologically healthy participants (NHP). It aimed to examine the facilitative role of gesture by determining whether gestures particularly accompanied WFD and whether those difficulties were resolved. Methods & Procedures: Spontaneous conversation data were collected from 20 PWA and 21 NHP. Video samples were analysed for gesture production, speech production, and WFD. Analysis 1 examined whether the production of semantically rich gestures in these conversations was affected by whether the person had aphasia, and/or whether there were difficulties in the accompanying speech. Analysis 2 identified all WFD in the data and examined whether these were more likely to be resolved if accompanied by a gesture, again for both groups of participants. Outcomes & Results: Semantically rich gestures were frequently employed by both groups of participants, but with no effect of group. There was an effect of the accompanying speech, with gestures occurring most commonly alongside resolved WFD. An interaction showed that this was particularly the case for PWA. NHP, on the other hand, employed semantically rich gestures most frequently alongside fluent speech. Analysis 2 showed that WFD were common in both groups of participants. Unsurprisingly, these were more likely to be resolved for NHP than PWA. For both groups, resolution was more likely if a WFD was accompanied by a gesture. Conclusions: These findings shed light on the different functions of gesture within conversation. They highlight the importance of gesture during WFD, both in aphasic and neurologically healthy language, and suggest that gesture may facilitate word retrieval

The role of semantically rich gestures in aphasic conversation

Introduction Gestures play an important role in everyday communication (Kendon, 1997). They provide additional information to conversation partners about the meaning of verbal utterances and help to clarify even abstract concepts. There is evidence that gestures are not simply produced for the benefit of the listener but also support the speaker (Krauss, Chen, & Chawla, 1996; McNeill, Cassell, & McCullough, 1994). The relationship between speech and gesture is of great theoretical interest. Indeed the strong ties between speech and gesture have stimulated discussions about the neurological links between the modalities and the possible gestural origins of language. Because of the importance of gesture in communication, several studies have investigated the use of gestures in aphasia (see Rose, 2006 for review). It is important to know how people with aphasia (PWA) use gesture as an accompaniment to speech, as a compensatory modality and during word-finding difficulties. Such knowledge can contribute to potential treatment regimes and may point to strategies that can assist everyday communication. Studying gesture use in people with compromised language can also contribute to the theoretical debate about the relationship between the modalities. Most studies to date have focused on the effects of gesture in structured naming tasks, rather than in more natural conversation. Methods Aims This study examines the natural conversational use of gestures in aphasic speech and addresses several research questions. This presentation focuses only on the following research questions: (1)To what extend to PWA and neurologically healthy participants (NHP) employ semantically rich gestures (i.e., gestures that convey stand alone meanings or reflect an aspect of the spoken discourse)? What impact does their semantic competence have on gesture production? (2)Do semantically rich gestures take different roles during conversation (facilitative, communicative, augmentative, compensatory)? (3)Do different topics, for example, narrative (i.e., telling about a life event) and procedural (i.e., describing a process) elicit different gesture patterns? Procedures Language and conversation data of 20 PWA and 21 NHP have been collected. Extensive background testing of PWA has been done including tests of lexical semantics and non-verbal semantics. Conversation samples of eight minutes in total have been collected. Video samples have been transcribed and analysed for gesture production, speech production and word-finding difficulties. Semantically rich gestures (e.g., they reflect concrete or abstract reference in the discourse (iconic, metaphoric and air writing & number gestures) or convey meaning in their own right (pantomime and emblem gestures)) were contrasted with semantically empty gestures (e.g., they refer to places or objects (deictic gestures) or mark speech rhythm (beat gestures). The roles of semantically rich gestures were coded to determine if participants are using gesture mainly to supplement speech, to replace speech or to facilitate lexical retrieval. The following methods are being used in the analysis: (1)All semantically rich gestures are identified within the conversation. (2)Semantically rich gestures which occur during a word finding difficulty (i.e. which occur within three seconds of word finding behaviour and before the next utterance) will be either categorised as being facilitative or communicative. a.If the word finding difficulty is resolved, the gesture will be categorised as being facilitative. b.If the word finding difficulty is not resolved (by the speaker), the gesture will be categorised as being communicative. (3)All other semantically rich gestures will be either categorised as being augmentative or compensatory. a.If a gesture occurs alongside speech and supplements it, it is considered as being augmentative. b.If a gesture is produced to replace speech, it will be categorised as being compensatory. Results The data analysis is on-going and results for both PWA and NHP will be available for presentation at the conference. Preliminary results indicate that PWA used significantly more semantically rich gestures than semantically empty ones (t(15) = 5.229, p < .05). Surprisingly, the semantic impairment did not correlate with the use of semantically rich gestures (rs = .053, n.s.; rs = .171, n.s.). Overall, semantically rich gestures took different roles (X2(3) = 34.956, p < .05). Most semantically rich gestures were produced during a procedural than a narrative conversation (t(15) = -2.538, p < .05). Discussion Semantically rich gestures play an important role in conversation for PWA. They can take different roles with many gestures being produced alongside speech (augmentative gestures) and those facilitating lexical access (facilitative gestures). Only a small number of gestures replace speech (compensatory gestures). Finding out more about the different roles of gestures in speech production, helps us to better understand the relationship between language and gestures. This is vital for gestures to be implemented into aphasia therapy

Semantisch reiche Gesten und ihre Funktion im Gespräch

Hintergrund und Fragestellung Alltägliche Kommunikation beschränkt sich nicht nur auf den verbalen Austausch von Information. Vielmehr spielen auch Gesten eine wesentliche Rolle. Bei Sichtkontakt vermitteln sie dem Gesprächspartner zusätzliche Informationen und tragen auch zur Erklärung abstrakter Inhalte bei. Studien weisen darauf hin, dass Gesten nicht nur zugunsten des Gesprächspartners produziert werden, sondern dass sie auch den Sprecher unterstützen. Durch ihre Bedeutung im Gespräch hat die Gestenproduktion bei Aphasie einen zentralen Bestandteil in der Forschung. Es ist wichtig, herauszufinden, wie Aphasiker (im Vergleich zu Sprachgesunden) Gesten sowohl sprachbegleitend als auch sprachersetzend im Gespräch einsetzen. Dieses Wissen kann einen Einfluss auf mögliche Behandlungsmethoden haben und Strategien aufzeigen, die die alltägliche Kommunikation unterstützen. Desweiteren kann die Erforschung der Gestenproduktion bei Spracheinschränkung auch zur theoretischen Diskussion über die Beziehungen zwischen Sprache und Gestik beitragen. Die meisten Studien haben sich bisher überwiegend auf die Auswirkungen von Gestik in strukturierten Benennaufgaben konzentriert. Diese Studie untersucht den Einsatz sprachbegleitender Gestik in natürlichen Gesprächssituationen, um so eine Reihe von relevanten Forschungsfragen zu beantworten: (1) In welchem Ausmaß produzieren Aphasiker und Kontrollpersonen semantisch reiche Gesten? (2) Welche Auswirkungen haben semantische Kompetenzen auf die Gestenproduktion? (3) Übernehmen semantisch reiche Gesten im Gespräch verschiedene Funktionen? Gibt es unterschiedliche Verteilungsmuster für Aphasiker und Kontrollpersonen? (4) Rufen verschiedene Gesprächsthemen (d.h. narrative und prozedurale) unterschiedliche Gesten hervor? Methodik 20 Aphasiker und 21 neurologisch gesunde Kontrollpersonen haben an der Studie teilgenommen. Im Vorfeld wurden eine Reihe linguistisch-kognitiver Tests durchgeführt, inklusive Tests zur Ermittlung verbaler und non-verbaler semantischer Fähigkeiten. Insgesamt wurden sechzehn Minuten an narrative und prozeduralen Gesprächsdaten erhoben. Videodaten wurden transkribiert und in Bezug auf Sprach- und Gestenproduktion analysiert. Semantisch reiche Gesten (ikonische, metaphorische, pantomimische, emblematische Gesten und Luftschreiben & Zahlen) wurden semantisch leeren Gesten (deiktische Gesten, Beats und andere Gesten) gegenüber gestellt. Weiterhin wurden Wortfindungsstörungen (WFS) und deren Kombination mit Gesten identifiziert, um verschiedene Funktionen semantisch reicher Gesten (fazilitativ, kommunikativ, unterstützend und ersetzend) zu ermitteln. Ergebnisse Sowohl Aphasiker als auch Kontrollpersonen verwendeten signifikant mehr semantisch reiche Gesten als semantisch leere (F (1,37) = 22.057, p < .001). Dies war insbesondere in den prozeduralen Gesprächen der Fall (F (1, 39) = 61.485, p < .001). Unterschiede zeigten sich bei den verschiedenen Funktionen der Gesten: Beide Gruppen verwendeten rund 50% aller Gesten zum Lösen von WFS. Während die andere Hälfte bei den Kontrollpersonen überwiegend sprachbegleitend zur zusätzlichen Informationsvermittlung eingesetzt wurde, gestikulierten Aphasiker zum großen Teil während nicht gelöster WFS. Sprachersetzende Gesten traten bei beiden Gruppen nur sehr selten auf. Überraschenderweise konnte bei den Aphasikern kein Zusammenhang zwischen verbalen und non-verbalen semantischen Fähigkeiten und der Produktion dieser Gesten festgestellt werden (rs (17) = .230, n.s.; rs (17) = .362, n.s.). Diskussion Die Studie bestätigt vorausgehende Ergebnisse, dass in Bezug auf Anzahl und Art der Gesten kein Unterschied zwischen Aphasikern und Kontrollpersonen festgestellt werden konnte. Erst mit der weiteren Betrachtung der Gestenfunktion wurden Unterschiede sichtbar: Während Kontrollpersonen Gesten überwiegend zur eigenen Unterstützung oder zur Untermalung des Gesprochenen verwendeten, gestikulierten Aphasiker mehr für ihren Gesprächspartner und zogen ihn in die aktive Suche bei WFS ein. Literatur Kendon, A. (1997). Gesture. Annual Review of Anthropology, 26, 109-128. Krauss, R. M., Chen, Y., & Chawla, P. (1996). Nonverbal behavior and nonverbal communication: What do conversational hand gestures tell us? In M. Zanna (Ed.), Advances in experimental social psychology (pp. 389-450). Diego, CA: Academic Press. McNeill, D., Cassell, J., & McCullough, K.-E. (1994). Communicative effects of speech-mismatched gestures. Research on Language and Social Interaction, 27(3), 223-237. Rose, M. L. (2006). The utility of arm and hand gestures in the treatment of aphasia. Advances in Speech-Language Pathology, 8(2), 92-109. Wilkinson, R. (2010). Interaction-focused intervention: A conversation analytic approach to aphasia therapy. Journal of Interactional Research in Communication Disorders, 1(1), 45-68

Die Funktion semantisch reicher Gesten im Gespraech bei Aphasie

Hintergrund und Fragestellung Gesten spielen eine wesentliche Rolle in alltäglichen Gesprächssituationen. Sie vermitteln dem Gesprächspartner zusätzliche Informationen zum Gesprochenen und tragen auch zur Erklärung abstrakter Inhalte bei. Studien weisen darauf hin, dass Gesten nicht nur zugunsten des Gesprächspartners produziert werden, sondern dass sie auch den Sprecher unterstützen. Die Beziehungen zwischen Sprache und Gestik sind von großem theroretischem Interesse und insbesondere die starken Bindungen zwischen Sprache und Gestik haben Diskussionen über die neurologischen Verbindungen der verschiedenen Modalitäten und deren möglichen genetischen Ursprung angeregt. Durch ihre Bedeutung im Gespräch hat die Gestenproduktion bei Aphasie einen zentralen Bestandteil in der Forschung. Es ist wichtig, herauszufinden, wie Aphasiker Gesten sowohl sprachbegleitend als auch sprachersetzend im Gespräch einsetzen. Dieses Wissen kann einen Einfluss auf mögliche Behandlungsmethoden haben und Strategien aufzeigen, die die alltägliche Kommunikation unterstützen. Desweiteren kann die Erforschung der Gestenproduktion bei Spracheinschränkung auch zur theoretischen Diskussion über die Beziehungen zwischen Sprache und Gestik beitragen. Die meisten Studien haben sich bisher überwiegend auf die Auswirkungen von Gestik in strukturierten Benennaufgaben konzentriert. Diese Studie untersucht den Einsatz sprachbegleitender Gestik in natürlichen Gesprächssituationen, um so eine Reihe von relevanten Forschungsfragen zu beantworten: (1) In welchem Ausmaß produzieren Aphasiker semantisch reiche Gesten? (2) Welche Auswirkungen haben semantische Kompetenzen auf die Gestenproduktion? (3) Übernehmen semantisch reiche Gesten im Gespräch verschiedene Funktionen? (4) Rufen verschiedene Gesprächsthemen (d.h. narrative und prozedurale) unterschiedliche Gesten hervor

The role of semantically rich gestures in aphasic conversation

Background: Gestures are spontaneous hand and arm movements that frequently accompany speech and play an important role in everyday communication (Kendon, 1997). Many gestures are semantically rich; for example, they reflect concrete or abstract reference in the discourse (iconic, metaphoric and air writing & number gestures) or convey meaning in their own right (pantomime and emblem gestures). Other gestures are semantically empty; for example, they refer to places or objects (deictic gestures) or mark speech rhythm (beat gestures). Finding out more about the different roles of gestures in speech production, helps us to better understand the relationship between language and gestures. This novel study addresses the following research questions: (1) To what extend do PWA and neurologically healthy participants (NHP) employ semantically rich gestures (iconic, metaphoric, pantomime, emblem and air writing & numbers) in comparison to semantically empty gestures (deictic, beat and other)? What impact does the semantic competence of PWA have on gesture production? (2) Do semantically rich gestures take different roles (facilitative, communicative, augmentative, compensatory) during conversation? (3) Do different conversation topics (i.e., narrative and procedural) elicit different gesture patterns

The use of semantically rich gestures in aphasic conversation

Background: Gestures play an important role in everyday communication. They provide additional information to conversation partners about the meaning of verbal utterances and help to clarify even abstract concepts. There is evidence that gestures are not simply produced for the benefit of the listener but also support the speaker. The relationship between speech and gesture is of great theoretical interest. Indeed the strong ties between speech and gesture have stimulated discussions about the neurological links between the modalities and the possible gestural origins of language. Because of the importance of gesture in communication, several studies have investigated the use of gestures in aphasia. Aphasia is a speech and language disorder caused by damage to the language areas of the brain e.g. because of stroke. It is important to know how people with aphasia (PWA) use gesture as both an accompaniment to speech and as a compensatory modality. Such knowledge can contribute to potential treatment regimes and may point to strategies that can assist everyday communication. Studying gesture use in people with compromised language can also contribute to the theoretical debate about the relationship between the modalities. Most studies to date have focused on the effects of gesture in structured naming tasks, rather than in more natural conversation

H2-powered aviation – Design and economics of green LH2 supply for airports

The economic competitiveness of hydrogen-powered aviation highly depends on the supply costs of green liquid hydrogen to enable true-zero CO2 flying. This study uses non-linear energy system optimization to analyze three main liquid hydrogen (LH2) supply pathways for five locations. Final liquid hydrogen costs at the dispenser supply costs could reach 2.04 USD/kgLH2 in a 2050 base case scenario for locations with strong renewable energy source conditions. This could lead to cost-competitive flying with hydrogen. Reflecting techno-economic uncertainties in two additional scenarios, the liquid hydrogen cost span at all five airport locations ranges between 1.37–3.48 USD/kgLH2, if hydrogen import options from larger hydrogen markets are also available. Import setups are of special importance for airports with a weaker renewable energy source situation, e.g., selected Central European airports. There, on-site supply might not only be too expensive, but space requirements for renewable energy sources could be too large for feasible implementation in densely populated regions. Furthermore, main costs for liquid hydrogen are caused by renewable energy sources, electrolysis systems, and liquefaction plants. Seven detailed design rules are derived for optimized energy systems for these and the storage components. This and the cost results should help infrastructure planners and general industry and policy players prioritize research and development needs

Reversible photodissipation of composite photochromic azobenzene-alginate supramolecular hydrogels

Supramolecular smart materials can quickly elicit macroscopic changes upon external stimulation. Here we report that an azobenzene-containing cyclic dipeptide can form composite supramolecular hydrogels with alginate based on the charge complementarity, at lower loading than the critical gelation concentrations of either component. The gels can reversibly dissipate to fluids with UV light. They can also encapsulate and photorelease fluorescent cargo. Upon treatment of the gels with aqueous calcium salts, the alginate component is permanently cross-linked and the photochromic component is solubilized