Phonologic Processing in Adults Who Stutter

Abstract

Event-related brain potentials (ERPs), judgment accuracy, and reaction times (RTs) were obtained for 11 adults who stutter and 11 normally fluent speakers as they performed a rhyme judgment task of visually presented word pairs. Half of the word pairs (i.e., prime and target) were phonologically and orthographically congruent across words. That is, the words looked orthographically similar and rhymed (e.g., thrown, own) or did not look similar and did not rhyme (e.g., cake, own). The phonologic and orthographic information across the remaining pairs was incongruent. That is, the words looked similar but did not rhyme (e.g., gown, own) or did not look similar but rhymed (e.g., cone, own). Adults who stutter and those who are normally fluent exhibited similar phonologic processing as indexed by ERPs, response accuracy, and RTs. However, longer RTs for adults who stutter indicated their greater sensitivity to the increased cognitive loads imposed by phonologic/orthographic incongruency. Also, unlike the normally fluent speakers, the adults who stutter exhibited a right hemisphere asymmetry in the rhyme judgment task, as indexed by the peak amplitude of the rhyming effect (difference wave) component. Overall, these findings do not support theories of the etiology of stuttering that posit a core phonologic-processing deficit. Rather we provide evidence that adults who stutter are more vulnerable to increased cognitive loads and display greater right hemisphere involvement in late cognitive processes.

Lexical and Phonological Processing in Visual Word Recognition by Stuttering Children: Evidence from Spanish

“…More importantly, it is consistent with previous findings in other languages in which stutterers have 6 Carlos J. Álvarez et al been shown to take longer to read words and sentences than persons without stuttering (Postma, Kolk, & Povel, 1990;Weber-Fox, Spencer, Spruill, & Smith, 2004). For example, in the study by Postma et al (1990), longer timeframes were found in different kinds of linguistic material production between stutterers and nonstutterers not only in the sub-vocalization and overt articulation conditions, but also in silent reading.…”

Uniqueness Point Effects during Speech Planning in Adults Who Do and Do Not Stutter

“…In terms of speech planning difficulties, a considerable amount of data implicate weaknesses in phonological encoding early in life as a key area of compromise (e.g., [7-9], for an opposing viewpoint, see [10, 11]), particularly for children whose stuttering persists into adulthood (e.g., [12-15]). These data are further supported by studies which indicate that many adults who stutter (AWS) perform more poorly than adults who do not stutter (AWNS) when completing experimental tasks that rely on efficient phonological processing (e.g., nonword repetition [16-18]; silent error monitoring [19]; phoneme elision [16, 17]; word jumble tasks [20]; silent rhyme judgment [21, 22]; silent phoneme monitoring [23-25]). Although differences in the phonological abilities of AWS are not unequivocal (cf.…”

Real-time processing in picture naming in adults who stutter: ERP evidence

“…For example, Weber-Fox (2001) reported that AWS versus TFA evidenced attenuated ERP effects to both grammatical and semantic word classes during a sentence reading task. In a later study, Weber-Fox et al (2004) reported that ERP correlates of phonological processing, elicited during a rhyme judgment task for pairs of printed words, were similar in AWS and TFA. The former findings were taken to indicate that neural functions related to lexical retrieval may be altered in AWS, while the latter findings were taken to indicate that adulthood stuttering may not stem from phonological processing deficits.…”