Orthographic experience during the acquisition of novel words may influence production processing in proficient readers. Previous work indicates interactivity among lexical, phonological, and articulatory processing; we hypothesized that experience with orthography can also influence phonological processing. Phonetic accuracy and articulatory stability were measured as adult, proficient readers repeated and read aloud nonwords, presented in auditory or written modalities and with variations in orthographic neighborhood density. Accuracy increased when participants had read the nonwords earlier in the session, but not when they had only heard them. Articulatory stability increased with practice, regardless of whether nonwords were read or heard. Word attack skills, but not reading comprehension, predicted articulatory stability. Findings indicate that kinematic and phonetic accuracy analyses provide insight into how orthography influences implicit language processing.

Purpose: The acquisition of literacy skills influences the perception and production of spoken language. We examined if orthography influences implicit processing in speech production in child readers and in adult readers with low and high reading proficiency. Method: Children (n = 17), adults with typical reading skills (n = 17), and adults demonstrating low reading proficiency (n = 18) repeated or read aloud nonwords varying in orthographic transparency. Analyses of implicit linguistic processing (segmental accuracy and speech movement stability) were conducted. The accuracy and articulatory stability of productions of the nonwords were assessed before and after repetition or reading.Results: Segmental accuracy results indicate that all 3 groups demonstrated greater learning when they were able to read, rather than just hear, the nonwords. Speech movement results indicate that, for adults with poor reading skills, exposure to the nonwords in a transparent spelling reduces the articulatory variability of speech production. Reading skill was correlated with speech movement stability in the groups of adults. Conclusions: In children and adults, orthography interacts with speech production; all participants integrate orthography into their lexical representations. Adults with poor reading skills do not use the same reading or speaking strategies as children with typical reading skills.

Linguistic demands influence speech motor production. Children with SLI show reduced speech motor performance in tasks that require language generation but not when task demands are reduced in rote practice.

BackgroundMany disease-specific factors such as muscular weakness, increased muscle stiffness, varying postural strategies, and changes in postural reflexes have been shown to lead to postural instability and fall risk in people with Parkinson's disease (PD). Recently, analytical techniques, inspired by the dynamical systems perspective on movement control and coordination, have been used to examine the mechanisms underlying the dynamics of postural declines and the emergence of postural instabilities in people with PD.MethodsA wavelet-based technique was used to identify limit cycle oscillations (LCOs) in the anterior–posterior (AP) postural sway of people with mild PD (n = 10) compared to age-matched controls (n = 10). Participants stood on a foam and on a rigid surface while completing a dual task (speaking).ResultsThere was no significant difference in the root mean square of center of pressure between groups. Three out of 10 participants with PD demonstrated LCOs on the foam surface, while none in the control group demonstrated LCOs. An inverted pendulum model of bipedal stance was used to demonstrate that LCOs occur due to disease-specific changes associated with PD: time-delay and neuromuscular feedback gain.ConclusionOverall, the LCO analysis and mathematical model appear to capture the subtle postural instabilities associated with mild PD. In addition, these findings provide insights into the mechanisms that lead to the emergence of unstable posture in patients with PD.

Speech production is influenced by the orthographic representation of the spoken word. Although previous work has shown that inconsistencies between the word’s sound and spelling may facilitate or disrupt processing (e.g., Alario, Perre, Castel, & Ziegler, 2007; Saletta, Goffman, & Brentari, 2015; Saletta, Goffman, & Hogan, 2016; Ventura, Morais, Pattamadilok, & Kolinsky, 2004), the developmental course of this effect on new readers remains unclear. The current study examines how children’s production of nonwords changes as a function of exposure to the nonwords’ orthography. We tested nonword repetition in 17 children with typical reading skills and 17 children with poor reading skills. Participants heard and repeated nonword stimuli, or read them aloud when the stimuli were written in either a relatively transparent or an opaque spelling. We quantified participants’ segmental accuracy and speech movement stability both before and after their exposure to the nonwords’ orthography. The children improved only in segmental accuracy (and not speech movement stability) and only as a consequence of practice (and not because of exposure to the nonwords’ spellings). Children with poorer reading skills demonstrated a greater change in accuracy from pretest to posttest than children with stronger reading skills. Thus, one’s automaticity in reading and the reorganization of his/her literacy skills throughout development influence speech production.