The Production of Gesture and Speech by People With Aphasia: Influence of Communicative Constraints

Abstract

Purpose People with aphasia (PWA) use different kinds of gesture spontaneously when they communicate. Although there is evidence that the nature of the communicative task influences the linguistic performance of PWA, so far little is known about the influence of the communicative task on the production of gestures by PWA. We aimed to investigate the influence of varying communicative constraints on the production of gesture and spoken expression by PWA in comparison to persons without language impairment. Method Twenty-six PWA with varying aphasia severities and 26 control participants (CP) without language impairment participated in the study. Spoken expression and gesture production were investigated in 2 different tasks: (a) spontaneous conversation about topics of daily living and (b) a cartoon narration task, that is, retellings of short cartoon clips. The frequencies of words and gestures as well as of different gesture types produced by the participants were analyzed and tested for potential effects of group and task. Results Main results for task effects revealed that PWA and CP used more iconic gestures and pantomimes in the cartoon narration task than in spontaneous conversation. Metaphoric gestures, deictic gestures, number gestures, and emblems were more frequently used in spontaneous conversation than in cartoon narrations by both participant groups. Group effects show that, in both tasks, PWA's gesture-to-word ratios were higher than those for the CP. Furthermore, PWA produced more interactive gestures than the CP in both tasks, as well as more number gestures and pantomimes in spontaneous conversation. Conclusions The current results suggest that PWA use gestures to compensate for their verbal limitations under varying communicative constraints. The properties of the communicative task influence the use of different gesture types in people with and without aphasia. Thus, the influence of communicative constraints needs to be considered when assessing PWA's multimodal communicative abilities.

Evaluating Models of Gesture and Speech Production for People With Aphasia

“…These statistics are different from those in De Beer et al (2019) for two reasons. First, in that study, the dependent variable was the gesture rate per minute instead of per 100 words, which lead to partly different results, because the speech rate differs between the two participant groups.…”

“…This might have prevented the retrieval of relevant information from memory. Furthermore, two of the participants (PWA02, PWA32) were diagnosed with having limb apraxia (see table 1 in De Beer et al, 2019), which probably limited their abilities to produce identifiable iconic gestures (see e.g., Hogrefe et al, 2012). Indeed, in the two mentioned PWA, the use of iconic gestures was very low in conversation as well as in the narration task (see Fig.…”

“…Seven PWA showed limitations of their verbal processing abilities and three participants' test results indicated limb apraxia. More detailed information on the PWA can be found in De Beer et al (2019).…”

“…This relationship is more appropriately reflected by the gesture‐to‐word ratios than by gesture rates per time unit. We define iconics following McNeill's (1992) definition of iconic gestures (see above), that is, subsuming the categories of iconic gestures and pantomimes (note that some scholars, e.g., De Ruiter [2000] and Sekine and Rose [2013], have classified pantomimes as a distinct category from iconic gestures, see De Beer, De Ruiter, Hielscher‐Fastabend, and Hogrefe [2019] 1 for separate analyses of the production of iconic gestures and pantomimes). Note that we follow De Ruiter (2000) in not distinguishing metaphoric gestures as a distinct category from iconics (please see De Ruiter, 2000, p. 285 for a more detailed explanation).…”

“… 1 1 In De Beer et al (2019), the authors studied the influence of varying communicative constraints on the relative distribution of PWA’s production of different gesture types. That study and the current study are based on the same raw data, collected from PWA and neurotypical controls.…”