Behavioral and brain evidence for language by ear, mouth, eye, and hand and motor skills in literacy learning

Long-Term Outcomes for Individuals With Childhood Apraxia of Speech

PURPOSE

The study's primary aims were to describe the long-term speech outcomes for adolescents and young adults with a history of childhood apraxia of speech (CAS) and to examine the association of persistent speech sound errors with measures of literacy skills, phonological processing, motor speech production, and parent report of early motor difficulty.

METHOD

Data from a large longitudinal 25-year study were used to explore outcomes for 32 individuals with a history of CAS, ages 12;6 (years;months) to 25 years (M = 17.4, SD = 4.7). Persistent and nonpersistent groups were compared on decoding, phonological processing, multisyllabic word repetition, diadochokinetic rate, and parent report of motor involvement. Parametric (Welch's t tests) and nonparametric tests (Wilcoxon and Fisher exact tests) were used to identify differences between the groups' distributions. Developmental trajectories of speech production were plotted.

RESULTS

Outcomes for individuals with CAS are highly variable, with some demonstrating speech sound errors into adolescence and young adulthood. Speech sound errors were primarily on later developing sounds. Persistence was significantly associated with early motor difficulties. Difficulties with multisyllabic words, phonological processing, and literacy were often present regardless of persistence or nonpersistence of speech errors.

CONCLUSIONS

Children with CAS are at risk for persistent speech sound errors into adulthood. For children showing limited progress with more traditional speech therapy, alternative interventions should be explored. Individuals with persistent speech sound errors are more likely to have a history of early motor deficits. Regardless of persistence, participants with CAS demonstrated ongoing weaknesses in literacy, phonological processing skills, and complex speech production tasks.

Capturing Neuroplastic Changes after iTBS in Patients with Post-Stroke Aphasia: A Pilot fMRI Study

Intermittent theta-burst stimulation (iTBS) is a high-efficiency transcranial magnetic stimulation (TMS) paradigm that has been applied to post-stroke aphasia (PSA). However, its efficacy mechanisms have not been clarified. This study aimed to explore the immediate effects of iTBS of the primary motor cortex (M1) of the affected hemisphere, on the functional activities and connectivity of the brains of PSA patients. A total of 16 patients with aphasia after stroke received iTBS with 800 pulses for 300 s. All patients underwent motor, language, and cognitive assessments and resting-state functional MRI scans immediately before and after the iTBS intervention. Regional, seed-based connectivity, and graph-based measures were used to test the immediate functional effects of the iTBS intervention, including the fractional amplitude of low-frequency fluctuation (fALFF), degree centrality (DC), and functional connectivity (FC) of the left M1 area throughout the whole brain. The results showed that after one session of iTBS intervention, the fALFF, DC, and FC values changed significantly in the patients' brains. Specifically, the DC values were significantly higher in the right middle frontal gyrus and parts of the left parietal lobe (p < 0.05), while fALFF values were significantly lower in the right medial frontal lobe and parts of the left intracalcarine cortex (p < 0.05), and the strength of the functional connectivity between the left M1 area and the left superior frontal gyrus was reduced (p < 0.05). Our findings provided preliminary evidences that the iTBS on the ipsilesional M1 could induce neural activity and functional connectivity changes in the motor, language, and other brain regions in patients with PSA, which may promote neuroplasticity and functional recovery.