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Background: Amnestic mild cognitive impairment (aMCI) is often the prodromal stage of Alzheimer's disease (AD). Although previous studies have suggested that computerized cognitive training is an effective non-pharmacological intervention for aMCI, large-sample, randomized controlled studies are warranted to provide a high level of evidence.Objective: To identify the efficacy of computerized cognitive training for aMCI.Methods: This study will include 260 patients diagnosed with aMCI from 8 centers in China. A computerized multi-domain adaptive training program will be used in this study, and the targeted cognitive domains include memory, attention, language, and executive function. The patients will be randomized into either a cognitive-training group or an active-control group. The intervention is a 12-week internet-based cognitive training performed for 40 minutes per day, 4 days a week. Neuropsychological assessments and structural and functional MRI will be obtained at baseline, at the end of the intervention, and 6 months after randomization. The primary outcome will be the global cognitive function score assessed by Montreal Cognitive Assessment. The secondary outcomes include changes in other neuropsychological assessments and neuroplasticity changes measured by structural and functional MRI.Results: The trial is currently ongoing, and it is anticipated that recruitment will be completed in December 2020.Conclusion: This multi-center, large-sample, randomized controlled trial will investigate the short and long-term effects of computerized cognitive training in patients with aMCI. Furthermore, the combination of functional and structural MRI results will also reveal the underlying mechanisms of the effect of intervention. [ABSTRACT FROM AUTHOR]

Semantic integration and working memory both decline with age. However, it remains unclear whether the semantic integration decline is independent of working memory decline or whether it can be solely explained by the latter factor. In this event-related potentials experiment, 43 younger adults and 43 cognitively healthy older adults read semantically congruent and incongruent sentences. After controlling for working memory, behavioral accuracy was significantly lower in the older adults than in the younger adults. In addition, the semantic integration related N400 effect (incongruent vs. congruent) for correct trials was apparent in the whole brain in the younger adults but restricted to the posterior region in the older adults. The results clarify the relationship between working memory and semantic integration, and clearly demonstrate that semantic integration decline is independent of working memory decline during aging. [ABSTRACT FROM AUTHOR]

While aging is associated with increased knowledge, it is also associated with decreased semantic integration. To investigate brain activation changes during semantic integration, a sample of forty-eight 25–75 year-old adults read sentences with high cloze (HC) and low cloze (LC) probability while functional magnetic resonance imaging was conducted. Significant age-related reduction of cloze effect (LC vs. HC) was found in several regions, especially the left middle frontal gyrus (MFG) and right inferior frontal gyrus (IFG), which play an important role in semantic integration. Moreover, when accounting for global gray matter volume reduction, the age-cloze correlation in the left MFG and right IFG was absent. The results suggest that brain structural atrophy may disrupt brain response in aging brains, which then show less brain engagement in semantic integration. [ABSTRACT FROM AUTHOR]

The relationship between impulsivity and cognitive control is still unknown. We hypothesized that trait impulsivity would differentially correlate with specific cognitive control processes. Trait impulsivity was measured by the Barratt Impulsiveness Scale, which assesses motor, attention, and non-planning impulsiveness components. Cognitive control was measured by a hybrid-designed Stroop task, which distinguishes proactive and reactive control. Thirty-three participants performed the Stroop task while they were scanned by functional magnetic resonance imaging. Proactive and reactive control involved increased activity in the fronto-parietal network, and brain activity was associated with impulsivity scores. Specifically, higher motor impulsiveness was associated with a larger proactive control effect in the inferior parietal lobule and a smaller reactive control effect in the right dorsolateral prefrontal cortex (DLPFC) and anterior cingulate contex. Higher attention impulsivity was associated with a smaller proactive control effect in the right DLPFC. Such a correlation pattern suggests that impulsivity trait components are attributable to different cognitive control subsystems. [ABSTRACT FROM AUTHOR]

• The age-related decline of semantic fluency was associated with brain structure decline. • Slowed processing speed contributes to semantic decline in aging. • Processing speed mediates the brain structure-semantic fluency correlation. The present study has investigated how brain structure and processing speed contribute to age-related changes in semantic fluency. Groups of younger (N = 37) and older healthy participants (N = 40) completed a semantic fluency test and digit symbol test, and rested while diffusion tensor imaging (DTI) was performed. Group comparisons and correlational analysis revealed that age-related decline in semantic fluency was associated with reduction in gray matter volume in widespread fronto-temporal regions. Age-related decline in semantic fluency was also associated with decline in white matter integrity in brain tracts connecting these brain regions. Critically, hierarchical regression analysis suggested that low processing speed fully mediated the negative effects of lower gray matter volume and white matter integrity on semantic fluency. The present findings provide a support for the processing speed theory in relation to age related decline in semantic fluency, and also provide a reference for improving cognitive decline. [ABSTRACT FROM AUTHOR]

Cross-sectional research has shown that older adults tend to have different frontal cortex activation patterns, poorer brain structure, and lower task performance than younger adults. However, relationships between longitudinal changes in brain function, brain structure, and cognitive performance in older adults are less well understood. Here we present the results of a longitudinal, combined fMRI-DTI study in cognitive normal (CN) older adults. A two time-point study was conducted in which participants completed a task switching paradigm while fMRI data was collected and underwent the identical scanning protocol an average of 3.3 years later (SD=2 months). We observed longitudinal fMRI activation increases in bilateral regions of lateral frontal cortex at time point 2. These fMRI activation increases were associated with longitudinal declines in WM microstructure in a portion of the corpus callosum connecting the increasingly recruited frontal regions. In addition, the fMRI activation increase in the left VLPFC was associated with longitudinal increases in response latencies. Taken together, our results suggest that local frontal activation increases in CN older adults may in part reflect a response to reduced inter-hemispheric signaling mechanisms. [ABSTRACT FROM AUTHOR]

Activation of left anterior inferior frontal gyrus (aLIFG) and left middle temporal gyrus (LMTG) has been observed in some functional neuroimaging studies of lexical decision but not others. It is thus unclear whether these two regions are necessary for word recognition. By applying continuous theta-burst transcranial magnetic stimulation (TMS) which temporally suppresses local brain function, we examined whether aLIFG and LMTG play causal roles in word recognition in a visual lexical decision task (LDT). Furthermore, we manipulated stimulus onset asynchrony (SOA) between prime and target to test whether these regions contribute to word recognition differently. In the LDT task, target words were preceded by semantically related primes (Related Condition; RC) or semantically unrelated words (Unrelated Condition; UC), under both short (150 ms) and long (600 ms) SOA conditions. TMS of aLIFG and LMTG significantly affected the word recognition speed compared to TMS of Vertex. Our results provide evidence that both aLIFG and LMTG contribute to word recognition speed. Furthermore, at short SOA, TMS of aLIFG or LMTG prolonged reaction time (RT). In contrast, at long SOA, there was a significant region by SOA by TMS interaction such that TMS of aLIFG prolonged RT, whereas TMS of LMTG speeded RT. These results suggest that aLIFG and LMTG may play different roles in word recognition. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that sentences are comprehended via widespread brain regions in the fronto-temporo-parietal network in explicit language tasks (e.g., semantic congruency judgment tasks), and through restricted temporal or frontal regions in implicit language tasks (e.g., font size judgment tasks). This discrepancy has raised questions regarding a common network for sentence comprehension that acts regardless of task effect and whether different tasks modulate network properties. To this end, we constructed brain functional networks based on 27 subjects’ fMRI data that was collected while performing explicit and implicit language tasks. We found that network properties and network hubs corresponding to the implicit language task were similar to those associated with the explicit language task. We also found common hubs in occipital, temporal and frontal regions in both tasks. Compared with the implicit language task, the explicit language task resulted in greater global efficiency and increased integrated betweenness centrality of the left inferior frontal gyrus, which is a key region related to sentence comprehension. These results suggest that brain functional networks support both explicit and implicit sentence comprehension; in addition, these two types of language tasks may modulate the properties of brain functional networks. [ABSTRACT FROM AUTHOR]

Abstract: Whether left inferior frontal gyrus (LIFG) activation during sentence comprehension reflects semantic integration or domain-general cognitive control remains unclear. To address this issue, 26 participants were presented with sentences word by word during fMRI scanning and were asked to perform two semantic tasks, one explicit (semantic congruency judgment) and one implicit (font size judgment). In the two language tasks, semantic integration load was parametrically manipulated with high cloze, low cloze and semantically violated sentences. Participants also performed a classical Stroop task during scanning. Conjunction analysis of the explicit and implicit tasks revealed two regions in left inferior frontal gyrus associated with semantic integration load: one anterior region (aIFG) and one posterior region (pIFG). However, only the pIFG region was also activated during the Stroop task. These results indicate that different regions in the LIFG play different roles in semantic integration, with aIFG more important for domain-specific processing and pIFG more important for domain-general cognitive control. [Copyright &y& Elsevier]

Abstract: Unlike common nouns, person names refer to unique entities and generally have a referring function. We used event-related potentials to investigate the time course of identifying the emotional meaning of nouns and names. The emotional valence of names and nouns were manipulated separately. The results show early N1 effects in response to emotional valence only for nouns. This might reflect automatic attention directed towards emotional stimuli. The absence of such an effect for names supports the notion that the emotional meaning carried by names is accessed after word recognition and person identification. In addition, both names with negative valence and emotional nouns elicited late positive effects, which have been associated with evaluation of emotional significance. This positive effect started earlier for nouns than for names, but with similar durations. Our results suggest that distinct neural systems are involved in the retrieval of names’ and nouns’ emotional meaning. [Copyright &y& Elsevier]

Abstract: Semantic unification, the process by which small blocks of semantic information are combined into a coherent utterance, has been studied with various types of tasks. However, whether the brain activations reported in these studies are attributed to semantic unification per se or to other task-induced concomitant processes still remains unclear. The neural basis for semantic unification in sentence comprehension was examined using event-related potentials (ERP) and functional Magnetic Resonance Imaging (fMRI). The semantic unification load was manipulated by varying the goodness of fit between a critical word and its preceding context (in high cloze, low cloze and violation sentences). The sentences were presented in a serial visual presentation mode. The participants were asked to perform one of three tasks: semantic congruency judgment (SEM), silent reading for comprehension (READ), or font size judgment (FONT), in separate sessions. The ERP results showed a similar N400 amplitude modulation by the semantic unification load across all of the three tasks. The brain activations associated with the semantic unification load were found in the anterior left inferior frontal gyrus (aLIFG) in the FONT task and in a widespread set of regions in the other two tasks. These results suggest that the aLIFG activation reflects a semantic unification, which is different from other brain activations that may reflect task-specific strategic processing. [Copyright &y& Elsevier]

Abstract: Using event-related functional MRI, we examined the involvement of the left inferior frontal gyrus (LIFG) in explicit and implicit semantic processing of Chinese sentences. During scanning, Chinese readers read individually presented normal sentences with a contextually expected or unexpected target noun and were asked to perform an explicit or implicit semantic task (semantic or syntactic violation judgment). The conjunction analysis of the two tasks revealed LIFG as the critical brain region for semantic integration. Further, a cross-task comparison showed more extensive activations for the expectancy effect in the explicit task than in the implicit task in regions including bilateral anterior cingulate cortex/dorsolateral prefrontal cortex, left middle temporal gyrus, and right inferior frontal gyrus. These results indicate that LIFG is responsible for the integration process per se and that other brain regions observed in previous studies using explicit semantic tasks may be due to task-induced generic processes (e.g., cognitive control). [Copyright &y& Elsevier]

Abstract: Numerous studies have documented cognitive impairments and hypoactivity in the prefrontal and anterior cingulate cortices in drug users. However, the relationships between opiate dependence and brain structure changes in heroin users are largely unknown. In the present study, we measured the density of gray matter (DGM) with voxel-based morphometry in 30 lifetime heroin-dependent individuals who had abstained from drug use for 5 months, and 34 healthy participants. The DGM of the prefrontal, temporal and cingulate cortices significantly decreased in heroin addicts relative to the healthy group. Critically, partial correlation analysis, which controlled for age, education and gender factors as well as nicotine use and heroin abstinence duration, showed that the duration of heroin use negatively correlated with the DGM in heroin-dependent individuals. These results provide compelling evidence for structural abnormality in heroin-dependent individuals and further suggest that duration of heroin use is a critical factor leading to brain damage. [Copyright &y& Elsevier]

Abstract: Using event-related functional MRI, we examined the involvement of the left inferior frontal gyrus (LIFG) in semantic integration in reading Chinese sentences. During scanning, Chinese readers read individually presented sentences and judged whether or not a sentence was semantically acceptable. Behaviorally, those sentences with a small degree of semantic violation were found to be more difficult to reject relative to sentences with a large degree of semantic violation, indicating that more semantic integration occurred in the former than in the latter condition. Direct contrast revealed significantly greater brain activity in the LIFG for sentences with a small violation, relative to those with a large violation, but no differences in any anterior temporal cortical areas between the two types of anomalous sentences. The results are in line with the idea that the LIFG plays a critical role in integrating individual word meanings to coherent sentence-level messages, but not with the idea that semantic integration depends on anterior temporal cortex in language comprehension. [Copyright &y& Elsevier]

Abstract: Event-related functional magnetic resonance imaging (ER-fMRI) was adopted to examine brain activation of syntactic processing in reading logographic Chinese. While fMRI data were obtained, 15 readers of Chinese read individually presented sentences and performed semantic congruency judgments on three kinds of sentences: Congruous sentences (CON), sentences with a semantic violation (SEM), and sentences with both semantic and syntactic violations (SEM+SYN). The two types of incongruous sentences were matched in the degree of semantic plausibility. Three brain regions were identified showing significantly different levels of percent signal change across the three conditions, including BA44 in the left inferior frontal gyrus (IFG) and both BA9 and BA10/46 in the left middle frontal gyrus (MFG). Furthermore, the mean percent signal change in the left BA44 observed in the SEM+SYN condition was significantly stronger than that in either the SEM or the CON condition, while the latter two conditions were at a similar level, implying an important role of this area in Chinese syntactic processing. These results, in conjunction with those found in alphabetic scripts, suggest that there are some common neural substrates underlie syntactic processing across distinctive writing systems such as the logographic Chinese and the alphabetic English. [Copyright &y& Elsevier]

Semantic unification during sentence comprehension has been associated with amplitude change of the N400 in event-related potential (ERP) studies, and activation in the left inferior frontal gyrus (IFG) in functional magnetic resonance imaging (fMRI) studies. However, the specificity of this activation to semantic unification remains unknown. To more closely examine the brain processes involved in semantic unification, we employed simultaneous EEG-fMRI to time-lock the semantic unification related N400 change, and integrated trial-by-trial variation in both N400 and BOLD change beyond the condition-level BOLD change difference measured in traditional fMRI analyses. Participants read sentences in which semantic unification load was parametrically manipulated by varying cloze probability. Separately, ERP and fMRI results replicated previous findings, in that semantic unification load parametrically modulated the amplitude of N400 and cortical activation. Integrated EEG-fMRI analyses revealed a different pattern in which functional activity in the left IFG and bilateral supramarginal gyrus (SMG) was associated with N400 amplitude, with the left IFG activation and bilateral SMG activation being selective to the condition-level and trial-level of semantic unification load, respectively. By employing the EEG-fMRI integrated analyses, this study among the first sheds light on how to integrate trial-level variation in language comprehension. • Semantic unification modulates N400 and BOLD signal in separated modality. • The specificity of BOLD response to semantic unification could be conflated by confounding effects. • Simultaneous EEG-fMRI recording was conducted to link the N400 related BOLD effect. • Activation in the left IFG and bilateral SMG response for condition and trial level variation of N400, respectively. • This is the first study to show trial level fluctuation in language stimuli. [ABSTRACT FROM AUTHOR]

The information about social hierarchical relationship has been intrinsically embedded into semantic restrictions of some Chinese verbs theoretically. For example, the Chinese verb ''(shanyang, support: provide for the needs and comfort of one's elders) only allows its Agent role to have a lower social status compared to the Patient role. However, whether this hierarchical restriction can be rapidly activated and how it impacts online thematic role assignment in reading remains to be seen. To answer this question, a 2 (Verb Type: hierarchical vs non-hierarchical verbs) × 2 (Social Hierarchy Sequence: match vs mismatch) design was constructed in the present study to investigate the interaction between the two factors. ERPs showed that hierarchical restriction violations evoked a stronger anterior negativity to the sentence-final noun (NP2). This effect was absent under two non-hierarchical conditions. To our knowledge, this study is the first to reveal that social hierarchical restrictions of Chinese hierarchical verbs can be rapidly available to guide online thematic role assignment and this process might be closely related to readers' thematic role knowledge. [ABSTRACT FROM AUTHOR]

The human brain is organized as a dynamic network, in which both regional brain activity and inter-regional connectivity support high-level cognitive processes, such as reading. However, it is still largely unknown how the functional brain network organizes to enable fast and effortless reading processing in the native language (L1) but not in a non-proficient second language (L2), and whether the mechanisms underlying local activity are associated with connectivity dynamics in large-scale brain networks. In the present study, we combined activation-based and multivariate graph-theory analysis with functional magnetic resonance imaging data to address these questions. Chinese–English unbalanced bilinguals read narratives for comprehension in Chinese (L1) and in English (L2). Compared with L2, reading in L1 evoked greater brain activation and recruited a more globally efficient but less clustered network organization. Regions with both increased network efficiency and enhanced brain activation in L1 reading were mostly located in the fronto-temporal reading-related network (RN), whereas regions with decreased global network efficiency, increased clustering, and more deactivation in L2 reading were identified in the default mode network (DMN). Moreover, functional network efficiency was closely associated with local brain activation, and such associations were also modulated by reading efficiency in the two languages. Our results demonstrate that an economical and integrative brain network topology is associated with efficient reading, and further reveal a dynamic association between network efficiency and local activation for both RN and DMN. These findings underscore the importance of considering interregional connectivity when interpreting local BOLD signal changes in bilingual reading. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate whether age-related brain response alterations during sentence comprehension exist when verbal fluency and intelligence are controlled for. Twenty-four younger and twenty-four older adults with matched verbal fluency, verbal intelligence, years of education, and gender ratio were recruited. They were asked to read congruent (CON) and incongruent (INCON) sentences to make semantic acceptability judgments. A significant group by condition interaction on accuracy was found, showing a significant congruency effect in younger, but not older adults. The ERP results revealed a dynamic temporal-spatial change in older adults. The congruency related N400 effect was reduced and delayed significantly in the older adults compared to the younger adults, and accompanied by different distribution patterns across time windows. The late positive component with more positive-going in the INCON condition than the CON condition was found in older adults only, which did not correlate with the performance, however. The results suggest that with age, there is a decline in semantic processing during sentence comprehension. [ABSTRACT FROM AUTHOR]

Background: Vascular cognitive impairment, no dementia (VCIND) refers to cognitive deficits associated with underlying vascular causes that fall short of a dementia diagnosis. There is currently no treatment for VCIND. Computerized cognitive training, which has significantly improved cognitive function in healthy older adults and patients with cognitive impairment has not yet been applied to VCIND.Methods/design: The proposed study is a three-center, double-blinded, randomized controlled trial that will include 60 patients with VCIND. The patients will be randomized to either a training or a control group. The intervention is internet-based cognitive training performed for 30 min over 35 sessions. Neuropsychological assessment and functional and structural MRI will be performed before and after 7 weeks training. Primary outcomes are global cognitive function and executive function. Secondary outcome measures are neuroplasticity changes measured by functional and structural MRI.Discussion: Applying an internet-based, multi-domain, adaptive program, this study aims to assess whether cognitive training improves cognitive abilities and neural plasticity in patients with subcortical VCIND. In addition to the comprehensive assessment of the participants by neuropsychological tests, cerebrovascular risk factors and apolipoprotein E genotyping, neuroplasticity will be used as an evaluation outcome in this study for, to our knowledge, the first time. The combination of functional and structural MRI and neuropsychological tests will have strong sensitivity in evaluating the effects of cognitive training and will also reveal the underlying mechanisms at work.Trial Registration: ClinicalTrials.gov NCT02640716 . Retrospectively registered on 21 December 2015. [ABSTRACT FROM AUTHOR]

The Stroop task is a classic paradigm that can be used to examine cognitive control as it contains conditions with and without interference. Cumulative evidence suggests that both stimulus and response conflict contribute to the Stroop interference effect. However, it remains unclear whether there are dissociable event-related potential (ERP) or frequency band-specific electroencephalographic (EEG) power changes associated with stimulus conflict and response conflict. To investigate potential markers for each form of conflict, we applied a Stroop 2-1 mapping task in 20 healthy young adults. Results showed that a negative deflection in the 350–500 ms time window (N450) and a positive deflection in the 600–900 ms time window (late positive component, LPC) were associated with response conflict and stimulus conflict, respectively. Time-frequency analyses found that both stimulus and response conflict induced theta band power changes and that response conflict additionally induced a beta band power change. These results indicate that stimulus and response conflict in the Stroop task are associated with different ERP effects and brain oscillatory features. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the functional significance of the late positive complex (LPC) in the Stroop task, the present study recruited 22 participants and had them report the color of words in the classical Stroop task and the rotation state of words in a Rotation judgment task. Color words whose ink color was either congruent (CON) or incongruent (INCON) with the word's meaning were presented in both tasks. Consistent with previous studies, the N450 and LPC were observed in the Stroop task, accompanied by slowed reaction time (RT) in the INCON condition compared with the CON condition. Notably, a larger LPC was observed in the INCON condition than in the CON condition in the Rotation task, while RT and accuracy were comparable between the two conditions. Because the incongruence between ink color and word meaning was independent from the response, and neither influenced accuracy nor RT in the Rotation task, the results suggested that the LPC may have resulted from the perceptual conflict between ink color and word meaning. [Copyright &y& Elsevier]

Abstract: Using fMRI, the present study compares the brain activation underlying false belief thinking induced by pictorial, nonverbal material to that instigated by strong non-factive verbs in a sample of adult Chinese speakers. These verbs obligatorily negate their complements which describe the mind content of the sentence agent, and thus may activate part of the false belief network. Some previous studies have shown a behavioral correlation between verb non-factivity/false complementation and conventional false belief but corresponding neural evidence is lacking. Our results showed that the non-factive grammar and false belief commonly implicated the right temporo-parietal junction (TPJ), which had been shown by past studies to play a role in general mentalizing. Regions that were unique to nonverbal false belief were the left TPJ and right middle frontal gyrus (MFG), whereas the unique regions for the non-factive grammar were the left inferior frontal gyrus (IFG) and right superior temporal gyrus (STG). Hence, conventional nonverbal false belief and verb non-factivity have both shared and unique neural representations. [Copyright &y& Elsevier]

Abstract: The present study investigates whether the complement falsity elicited by strong non-factive verbs and the false belief activated by a standard nonverbal false belief task produce similar electrophysiological activities in the brain. The hypothesis is based on the notion that both complement falsity and false belief involve decoupling a false mental representation from reality. Some previous studies have reported a behavioral correlation between children''s false belief reasoning and interpretation of strong non-factive verbs together with their false complements, but a neural basis for this correlation has not been found. Our event-related potential (ERP) results with normal adults showed that both nonverbal false belief and strong non-factive verb comprehension elicited a negative late slow waveform divergence compared to their respective baselines. Although these slow waves due to the two types of stimuli had slightly different scalp distributions, both were regarded as reflecting primarily frontal activation. Such ERP similarity provides evidence for a common neural basis shared by nonverbal false belief reasoning and comprehension of strong non-factive verbs. [Copyright &y& Elsevier]

The present fMRI study examined the neural basis of processing context-supported or -unsupported interpretations of ambiguous morphemes during Chinese compound word reading in a masked priming lexical decision task. Targets were Chinese bimorphemic words that contained ambiguous morphemes. Prime words contained the same ambiguous morphemes with either the same meanings (context-supported interpretation) or different ones (context-unsupported interpretation). Lexical-level semantic sharing and unrelated control conditions were also included. Compared to the unrelated control condition, the context-supported morphemic meaning was associated with increased activity in the left SFG and bilateral MTG, and this priming effect could be dissociated from that of the lexical-level semantic-related condition. In broader brain regions, including the left SFG, bilateral MTG, left STG, right IOG, and left precuneus, the context-unsupported meaning condition showed decreased activity compared with the unrelated control condition. These findings indicate that both the context-supported and -unsupported meanings evoke significant priming effects, however, they differ from each other with different brain basis, providing new insight into the neural substrates of ambiguous morpheme processing. • Left SFG and bilateral MTG are core brain regions in ambiguous morpheme processing. • Each distinct morphemic meaning of ambiguous morphemes has independent neural entry. • Contextual information would modulate the activation pattern of each interpretation of ambiguous morphemes. [ABSTRACT FROM AUTHOR]

It has been well established that syntactic representation is independent of semantic representation in Indo-European languages, but it is unclear whether this is the case in Chinese. The present functional magnetic resonance imaging (fMRI) study adopted a syntactic priming paradigm to investigate the neural basis of Chinese syntactic representation. A passive sentence was preceded by either a passive or an active sentence without repeating a verb or a pattern of agent-patient animacy, thus constructing primed and unprimed sentence pairs based on sentence structure. The fMRI data were collected from 22 native Chinese speakers while they were reading the sentences. Priming-related activation suppression was found in the left temporal pole, left inferior frontal gyrus and left precentral gyrus. The results are the strongest neuroimaging evidence to date that syntactic representation is independent of semantic representation in Chinese, in line with Indo-European languages. [ABSTRACT FROM AUTHOR]

A meaningful sentence might not be sensible according to world knowledge. In aging, world knowledge continues to increase, but semantic processing declines. An intriguing question is whether increased world knowledge aids world knowledge comprehension, even in the face of declining semantic processing. The present study collected EEG data from 43 older and 43 younger adults as they read correct sentences, sentences with a semantic violation, and sentences with a world knowledge violation. Compared to younger adults, older adults had a significantly greater reduction in amplitude and delayed peak/onset latency of N400 for both semantic and world knowledge integration. A significant Group by Condition by Region interaction revealed that, although the N400 amplitude under the semantic violation condition was comparable to that under the world knowledge violation condition in younger adults, the N400 amplitude in the posterior brain region was significantly smaller under the world knowledge violation condition than under the semantic violation condition in older adults. The N400 difference between world knowledge and semantic violation conditions was negatively correlated only with vocabulary scores. In conclusion, age-related increases in world knowledge do not help older adults to comprehend world knowledge more effectively. [ABSTRACT FROM AUTHOR]

Background: Mild cognitive impairment (MCI) is a transition state between asymptomatic stage and dementia. Amnestic MCI (aMCI) patients who mainly present with memory deficits are highly likely to progress to Alzheimer's disease (AD). At present, no broadly effective drug therapy is available to prevent the progression from memory deficit to dementia. Cognitive control training, which has transfer effects on multiple cognitive capacities including memory function in healthy old adults, has not yet been applied to aMCI.Methods/design: In this single-center, randomized double-blind placebo-controlled study, 70 aMCI patients will be recruited and randomly assigned to the training and control groups. The intervention is an Internet-based cognitive control training program performed for 30 min daily, five days per week, for 12 consecutive weeks. Neuropsychological assessment and structural and functional magnetic resonance imaging (MRI) will be performed at baseline and outcome. Primary outcomes are changes of episodic memory retrieval function. Secondary outcome measures are neuroplasticity changes measured by functional and structural MRI.Discussion: In this study, an Internet-based cognitive control training program is adopted to investigate whether cognitive control training can enhance the retrieval of episodic memory in aMCI patients. The combination of multi-modal MRI and neuropsychological tests could have a good sensitivity in evaluating the effects of cognitive control training and could also uncover the underlying neural underpinning.Trial Registration: ClinicalTrials.gov, NCT03133052 . Registered on 21 April 2017. [ABSTRACT FROM AUTHOR]