Persistent developmental stuttering (PDS) is a speech disorder that impairs communication skills. Despite extensive research, the core causes of PDS are elusive. Converging evidence from task-induced neuroimaging methods has demonstrated the contributions of the basal ganglia and the cerebellum to PDS, but such task-state neuroimaging findings are often confounded by behavioral performance differences between subjects who stutter and normal controls. Here, using resting-state functional magnetic resonance imaging, we investigated functional connectivity within cerebellar-cortical and basal ganglia-thalamocortical networks in 16 adults who stutter and 18 age-matched fluent speakers. Seed-to-voxel analysis demonstrated that, compared to controls, adults who stutter showed alternations in functional connectivity of cerebellum to motor cortex as well as connectivity among different locals within cerebellum. Additionally, we found that functional connectivity within cerebellar circuits was significantly correlated with severity of stuttering. The alternations of functional connectivity within basal ganglia-thalamocortical networks were identified as the reduced connectivity of the putamen to the superior temporal gyrus and inferior parietal lobules in adults who stutter. The abnormalities of resting state functional connectivity are assumed to affect language planning and motor execution critical for speaking fluently. Our findings may yield neurobiological cues to the biomarkers of PDS.

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We used functional magnetic resonance imaging (fMRI) to map the neural systems involved in reading Chinese in 125 participants 6–74 years old to examine two theoretical issues: how brain structure and function are related in the context of the lifetime neural development of human cognition and whether the neural network for reading is universal or different across languages. Our findings showed that a common network of left frontal and occipital regions typically involved in reading Chinese was recruited across all participants. Crucially, activation in left mid-inferior frontal regions, fusiform and striate–extrastriate sites, premotor cortex, right inferior frontal gyrus, bilateral insula, and supplementary motor area all showed linearly decreasing changes with age. These findings differ from previous findings on alphabetic reading development and suggest that early readers at age 6–7 are already using the same cortical network to process printed words as adults, though the connections among these regions are modulated by reading proficiency, and cortical regions for reading are tuned by experience toward reduced and more focused activation. This fMRI study has demonstrated, for the first time, the neurodevelopment of reading across the lifespan and suggests that learning experience, instead of pre-existing brain structures, determines reading acquisition.

Persistent developmental stuttering is a neurological disorder that commonly manifests as a motor problem. Cognitive theories, however, hold that poorly developed cognitive skills are the origins of stuttering. Working memory (WM), a multicomponent cognitive system that mediates information maintenance and manipulation, is known to play an important role in speech production, leading us to postulate that the neurophysiological mechanisms underlying stuttering may be associated with a WM deficit. Using functional magnetic resonance imaging, we aimed to elucidate brain mechanisms in a phonological WM task in adults who stutter and controls. A right-lateralized compensatory mechanism for a deficit in the rehearsal process and neural disconnections associated with the central executive dysfunction were found. Furthermore, the neural abnormalities underlying the phonological WM were independent of memory load. This study demonstrates for the first time the atypical neural responses to phonological WM in PWS, shedding new light on the underlying cause of stuttering.

a b s t r a c tIn this study we investigate how the human brain processes small clauses and finite clauses. Small clauses are instances of 'simpler' syntax in the sense that they do not involve operations such as Move and Tense, and have been argued to represent an earlier stage of syntactic evolution before the development of fully-fledged syntax (Bickerton, 1990;Jackendoff 2010;Uriagereka, 2008). Understanding how the brain processes instances of different levels of syntactic complexity may further our understanding of (i) the analytical functions of specific brain regions, and (ii) the distribution of labor in the interpretation or different levels of syntax. To pursue this hypothesis, we ask whether small clauses require different analytical processes than regular syntax. This report provides evidence that they do. In an fMRI study of syntactic processing in a group of Mandarin speakers, small clauses showed greater activation of areas involved in semantic processing. In addition, both small and finite clauses showed substantial activation of areas implicated in syntactic and semantic processing, including significant RH activation.

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Human learning and cognitive functions change with age and experience, with late-developed complex cognitive functions, particularly those served by the prefrontal cortex, showing more age-dependent variance. Reading as a complex process of constructing meaning from print uses the left prefrontal cortex and may show a similar aging pattern. In this study, we delineated the lifespan developmental changes in the neural substrates and functional connectivity for visual semantic processing from childhood (age 6) to late adulthood (age 74). Different from previous studies that reported aging as a form of activation or neuronal changes, we examined additionally how the functional connectivity networks changed with age. A cohort of 122 Chinese participants performed semantic and font-size judgment tasks during functional magnetic resonance imaging. Although a common left-lateralized neural system including the left mid-inferior prefrontal cortex was recruited across all participants, the effect of age, or reading experience, is evident as 2 contrastive developmental patterns: a declining trend in activation strength and extent and an increasing trend in functional connections of the network. This study suggests that visual semantic processing is not prone to cognitive decline, and that continuous reading until old age helps strengthen the functional connections of reading-related brain regions.

How learning a second language (L2) changes our brain has been an important question in neuroscience. Previous neuroimaging studies with different ages and language pairs spoken by bilinguals have consistently shown plastic changes in brain systems supporting executive control. One hypothesis posits that L2 experience-induced neural changes supporting cognitive control, which is responsible for the selection of a target language and minimization of interference from a non-target language. However, it remains poorly understood as to whether such cognitive advantage is reflected as stronger controlled processing or increased automatic inhibition processing. In this study, using functional MRI we scanned 27 Chinese-English late bilinguals while they performed a Simon task. Results showed that bilinguals with higher L2 vocabulary proficiency performed better in the Simon task, and more importantly, higher L2 vocabulary proficiency was associated with weaker activation of brain regions that support more general cognitive control, including the right anterior cingulate cortex, left insula and left superior temporal gyrus. These results suggest that L2 experience may lead to a more automatic and efficient processing in the inhibitory control task. Our finding provides an insight into neural activity changes associated with inhibitory control as a function of L2 proficiency.