Signaling Noncomprehension of Language: A Comparison of Fragile X Syndrome and Down Syndrome

Abstract

Signaling noncomprehension of the spoken messages of others was examined for youth with fragile X or Down syndrome in comparison with each other and nonverbal MA-matched typically developing children. A direction-following task was used in which some of the directions were inadequate. Both syndrome groups signaled noncomprehension less often than did the typically developing children. The ability to signal noncomprehension appropriately was related to a measure of receptive vocabulary and syntax. Preliminary analyses indicated that males with fragile Requests for reprints should be sent to Leonard Abbeduto, Waisman Center, University of Wisconsin-Madison, 1500 Highland Ave., Madison, WI 53705. Abbeduto@waisman.wisc.edu. HHS Public AccessAuthor manuscript Am J Ment Retard. Author manuscript; available in PMC 2017 September 25. Author Manuscript Author ManuscriptAuthor Manuscript Author Manuscript X syndrome signaled noncomprehension less often than did their female peers, even after controlling for differences in nonverbal MA.For a discourse to be successful, the participants must fulfill the obligations associated with their roles as speaker and listener (Clark, 1996). In the role of listener, a participant must use all available sources of information to construct the speaker's intended meaning. Moreover, the listener must signal when comprehension is not possible so that the speaker can provide clarification. If the listener fails to signal noncomprehension, he or she will find it increasingly difficult to construct an accurate representation of the talk and to make meaningful contributions (Clark & Schaefer, 1989). Individuals with intellectual disabilities often fail to signal noncomprehension (Abbeduto, Davies, Solesby, & Furman, 1991;Abbeduto, Short-Meyerson, Benson, & Dolish, 1997;Abbeduto, Short-Meyerson, Benson, Dolish, & Weissman, 1998;Ezell & Goldstein, 1991;Fujiki & Brinton, 1993). There is, however, considerable within-group variability in most domains of language use, including noncomprehension signaling (Abbeduto & Rosenberg, 1980;Bedrosian & Prutting, 1978). The causes and correlates of such variability are poorly understood (Abbeduto & Hesketh, 1997). In this study, we examined the possibility that the nature and extent of problems in noncomprehension signaling vary with etiology by focusing on Down syndrome and fragile X syndrome, the two most common genetic causes of intellectual disabilities (Dykens, Hodapp, & Finucane, 2000). We also examined the sources of between-and withinsyndrome differences in non-comprehension signaling. Such data can provide the foundation for language interventions designed to meet the unique needs of the individual with intellectual disabilities (Dykens et al., 2000;Hodapp & Fidler, 1999;Murphy & Abbeduto, 2005).Signaling noncomprehension requires that the listener continuously monitor his or her understanding and formulate linguistic responses that make clear to the speaker what aspects of the utterance are problematic and, thereby, the nature of the clar...

Noncomprehension Signaling in Males and Females With Fragile X Syndrome

“…In fact, Abbeduto et al (2008) examined the ability of 18 adolescents and young adults with FXS (13 boys, 5 girls; mean CA = 17.58 years) to signal noncomprehension of the spoken messages of others, using a direction-following task in which some of the messages were inadequate because (a) the speaker referred to an unavailable object (Incompatible), (b) the speaker's direction was too nonspecific to indicate which object of several available was the intended object (Ambiguous), or (c) the speaker's direction contained an adjective unknown to the participant (Unfamiliar). Abbeduto et al found that the youth with FXS were less likely to signal noncomprehension of inadequate messages than were younger, nonverbal mental age-matched TD children.…”

“…The Abbeduto et al (2008) study, however, suffered from a number of limitations that restrict its clinical utility. In particular, the study had a cross-sectional design, relatively small sample size, and/or a very wide age range of participants.…”

“…This task, which was modeled after Abbeduto et al (2008), was designed to individually assess each participant's ability to verbalize when the referent in a speaker's one-sentence direction could not be identified with certainty. Two examiners were involved in the administration: a primary examiner who explained the task instructions and a second experimenter who served as the "speaker."…”

“…In such tasks, the speaker's goal is to convey information that will enable a listener to identify a target referent from confusable alternatives; the listener's goal is to correctly identify the referent or inform the speaker when the target referent cannot be identified (e.g., Morisseau, Davies, & Matthews, 2013;Nilsen, Mangal, & MacDonald, 2013;Rosenberg & Cohen, 1964). Younger TD children and children with intellectual disabilities, however, have difficulty with such noncomprehension signaling in referential tasks (Abbeduto et al, 2008;Ackerman, 1981;Beal & Belgrad, 1990;Fujiki & Brinton, 1993;Robinson & Whittacker, 1985). For example, it has been shown that 5-to 6-year-old TD children encounter difficulty with regard to consistently evaluating utterances for their referential adequacy, particularly when presented with ambiguous directions (i.e., directions that refer equally well to multiple entities; Ackerman, 1981;Robinson & Whittacker, 1985).…”

“…When considering noncomprehension signaling in adults with mild to moderate intellectual disability, Fujiki and Brinton (1993) reported a similar pattern of poor performance on referentially ambiguous messages. Furthermore, difficulties with noncomprehension signaling have been documented in individuals with a variety of genetic conditions associated with intellectual disability (e.g., autism spectrum disorder [ASD], Down syndrome, FXS, Williams syndrome; e.g., Abbeduto et al, 2008;Asada, Tomiwa, Okada, & Itakura, 2010;John, Rowe, & Mervis, 2009;Loveland, Tunalia, McEvoy, & Kelley, 1989;Skwerer, Ammerman, & TagerFlusberg, 2013). Thus, difficulties with regard to a listener's role in conversational exchanges appear to persist in individuals with intellectual disabilities far longer than is observed in TD.…”