Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Mild cognitive impairment (MCI) is an intermediate state between normal aging and dementia, which does not affect activities of daily living. Patients with MCI typically show deficits in memory, attention, executive function, language and speech, which are related to the altered connectivity of large-scale brain networks, such as salience network, frontal-parietal network, and default mode network. MCI is associated with an increased risk of Alzheimer’s disease, but there lacks effective pharmacologic therapy of MCI. Repetitive transcranial magnetic stimulation (rTMS) is widely applied to enhance cognitive functions by modulating synaptic plasticity. However, there is a lack of studies examining effects of rTMS on MCI, and no consensus on its effectiveness and mechanisms has been reached. To address this problem, a literature review was conducted by searching literature in databases of Web Of Science, PubMed, PsycINFO, China National Knowledge Infrastructure, and by assessing the quality of included studies using the Cochrane Collaboration’s tool. The results showed that the studies included in this review had a low risk of bias. Performing high-frequency rTMS on inferior frontal cortex (IFG) and superior temporal cortex (STG) improved attention in patients with MCI, by increasing the excitability of the attention network. High-frequency rTMS of dorsolateral prefrontal cortex (dlPFC) improved executive function. rTMS-excitation of dlPFC and precuneus enhanced episodic memory in MCI patients, and its underlying mechanism might be that rTMS improved the encoding function of dlPFC and the retrieving function of ventral precuneus. Based on that the increasing activity of right dlPFC is associated with the decreasing activity of hippocampus, the inhibition of dlPFC improved long-term memory in patients with MCI. Conducting high-frequency rTMS on medial prefrontal cortex (mPFC) could strengthen the connectivity among neuronal subpopulations in mPFC, improving the short-term memory of patients with MCI. Based on the strong functional connectivity between posterior parietal cortex (PPC) and hippocampus, performing high-frequency rTMS on parietal cortex could activate hippocampus by the PPC-hippocampus connection, which improves associative memory of patients with MCI. High-frequency rTMS over prefrontal cortex (PFC) improved associative memory, which was related to the additional activation of right IFG and middle frontal gyrus, reflecting a compensatory mechanism in associative memory. rTMS shows effects in improving attention, executive function, episodic memory, long-term and short-term memory, and associative memory in patients with MCI. The improving effects could keep for 30 days, 8 weeks, or 6 months. No significant adverse effects of rTMS were reported in these studies. The major strengths of this review included that the inclusion and the quality assessment of studies followed standard protocol, and that the examinations of the rTMS effects on MCI and its underlying mechanisms were conducted comprehensively in terms of the affected multiple cognitive domains. Future studies should optimize the localization for TMS, extend the evaluation period of intervention effects, and explore how rTMS works in the treatment of MCI combining with neuroimaging technologies.
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Developmental dyslexia (hereafter referred as "dyslexia") will not only affect the lifelong development of individuals but also impose an additional financial burden on society. Digging into the relevant neural mechanisms contributes to the early prediction and intervention of dyslexia. Established models of the neural bases of dyslexia primarily focused on the cerebrum. In recent years, extensive studies have shown that dyslexia is also associated with cerebellar abnormalities. However, it remains unclear about the relationships between the two. By summarizing recent findings, we found that the cerebellum could play multiple roles in reading. First, it could influence reading in different ways. Cerebellar dysfunctions could impair reading by affecting motor or motor-related skills (such as oculomotor control, automatization, or articulation), or by disturbing linguistic-related processes (such as phonological or semantic processing). Second, different subtypes of dyslexia are associated with abnormalities in distinct cerebellar regions. For example, dyslexic readers with automatization deficits showed abnormal neural activities in the anterior parts of the cerebellum, which were responsible for motor processing, whereas dyslexic readers suffering from visual and phonological deficits were associated with the abnormalities in the gray matter volume of the posterolateral areas of the cerebellum, which were mainly responsible for high-level cognitive processing. These results indicate that the relationship between dyslexia and the cerebellum is not unitary. There may exist multiple cerebellar areas being targeted by dyslexia, which also contribute differently to reading. The causal relationships between cerebellar abnormalities and dyslexia might be bi-directional. Previous literature found that structural deficits in the posterolateral parts of the cerebellum were only associated with dyslexia compared to other development disorders (i.e., ADHD, autism) that may coexist with dyslexia. This result suggests that neural abnormalities in these areas were due to deficits in reading abilities rather than other comorbidities. Additionally, these regions vary in their causal relationships with dyslexia. For example, activation in the anterior parts of the right lobule VI, responsible for motor processing, showed greater activation or functional connectivity with the cerebrum in dyslexic readers compared to normal readers. These increased neural activities may be the compensatory mechanisms of dyslexia and a by-product of reading difficulties. In contrast, neural activities of the cerebellar areas responsible for linguistic processing (i.e., the right lobule VII) could predict future reading abilities, indicating that the functional state of the cerebellum in early developmental stages may influence reading development. Moreover, functional deactivations in the cerebellar linguistic areas have been observed in preschool readers with a high risk of dyslexia, suggesting that cerebellar abnormalities have occurred before formal reading instruction. These results jointly support that cerebellar abnormalities may be the cause of dyslexia. The results mentioned above illustrate that the cerebellum is more than a reading-related hub. There could be multiple cerebellar regions that are engaged in reading, with different regions supporting different cognitive processes and having distinct causal relationships with dyslexia. Accordingly, we introduced the "cerebro-cerebellar mapping hypothesis of word reading", which proposed that reading-related regions in the cerebellum map to their functional correspondence areas in the cerebrum. Regions with the same functions across the cerebrum and cerebellum synchronized in neural activities and collaborated during reading. Dysfunctions of this collaboration may lead to dyslexia. This new framework aims to reveal the relationship between reading, the cerebellum, and the cerebrum from a new perspective, and offers important insights into the neural mechanism of dyslexia and the role of the cerebellum in high-level cognitive processing.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： The approximate number system (ANS) underlies the ability to approximately represent numerical magnitude or to estimate the number of a quantity without counting. ANS acuity is a reliable predictive factor of mathematical achievements and is most likely not influenced by educational or cultural factors of general cognitive processing. It is well established that individuals with mathematics anxiety (MA) perform normally in general cognitive tasks but significantly below-average in mathematical tasks such as numerical magnitude processing, computation and mathematical problem solving. Previous behavioral study reported significant negative correlations between MA level and ANS acuity but it remained unclear whether MA individuals are deficient in their ANS functioning. The current study explored the approximate number processing in individuals with mathematics anxiety at a neural level and gathered electrophysiological evidences for ANS deficiency in MA individuals. We selected 31 individuals with high math anxiety and 29 individuals with low math anxiety who were matched for mean general intelligence, rapid visual perception ability, visual searching ability and mean general anxiety level. The participants completed a dot array task both actively and passively as their electroencephalogram (EEG) data were recorded. In the active dot array task, the participants were required to make judgements on the relative quantities of blue and yellow dots while the ratio of the dots were manipulated to be high or low. In the passive viewing task, the participants were required to complete an irrelevant task to ensure that proper attention was paid to the stimuli while the ratio was also manipulated. We found that the behavioral performances of the two groups were comparable in both active and passive viewing tasks. However, event-related potential (ERP) analysis revealed that the high anxiety group had larger P2p amplitudes at the occipital electrodes than the low anxiety group in both active and passive viewing tasks. Furthermore, time-frequency analysis was performed and significant ratio effects were found in the low anxiety group in δ band (1~5 Hz) event-related synchronization (ERS) and β band (29~34 Hz) event-related desynchronization (ERD) while no ratios effects were found in the low anxiety group. The current study provided electrophysiological evidences for ANS deficiencies in individuals with MA. The findings of this study have important theoretical implications for the causes of the impaired mathematical abilities in MA individuals as well as for effective interventions for MA.
Subjects: Psychology >> Cognitive Psychology submitted time 2021-09-07
Abstract： Facial expressions are an important medium for understanding the emotional feelings of others. However, individual factors such as gender, age, and personality traits can influence the perception of facial expressions. For instance, individuals with elevated level of trait anxiety, which is measure of frequency and intensity of occurrence of anxiety related symptoms, show attentional bias towards emotional stimuli, that is, higher attention to emotional information such as facial expressions. These studies mostly focused on attentional processing stage, and it remains unclear whether trait anxiety affects the pre-attentive processing stage of facial expression perception. Pre-attentive processing is an automatic evaluation of whether attention is needed for the stimulus, thereby filtering out irrelevant information to conserve cognitive resources and improve the efficiency of information processing. Therefore, the present study aimed to investigate the pre-attentive processing of facial expressions and the bias to emotional stimuli of trait anxious individuals to emotional stimuli during the pre-attentive processing stage. According to the scores of Spielberger State-Trait Anxiety inventory (STAI), 20 participants who scored in the top 27% were assigned to the high trait anxiety group (13 women; mean age=19.02 ± 0.63 years) and 20 participants who scored in the bottom 27% were assigned to the low trait anxiety group (11 women; mean age=19.63 ± 0.88 years). The stimuli used in the experiment were happy, sad and neutral face pictures selected from the Chinese Facial Affective Picture System (CAFPS; Gong et al., 2011) including 10 pictures (5 females and 5 males) of each kind of emotion. The deviant-standard-reverse oddball paradigm included 4 types of facial expression sequences: neutral standard stimuli/happy deviant stimuli, happy standard stimuli/neutral deviant stimuli; neutral standard stimuli/sad deviant stimuli, and sad standard stimuli/neutral deviant stimuli. The standard stimuli mean that this type of stimuli were appeared about 80% of the time in the sequence, and the deviant stimuli were about 20%. Participants were instructed to detect unpredictable changes in the size of fixation cross in the center of visual field and press a corresponding button as fast and as accurate as possible, and ignored facial expressions. The results revealed that, the amplitudes of N170 elicited by deviant faces were significantly larger than standard faces. Importantly, in the early EMMN, the mean amplitude elicited by sad facial expressions was significantly larger than happy facial expressions in low trait anxiety group, but there was no significant difference between happy and sad facial expressions in high trait anxiety group. Moreover, the early EMMN amplitude of happy faces was significantly larger in the high trait anxiety group than in the low trait anxiety group. These results suggest that the high trait anxiety group has similar amplification of EMMN amplitude for both happy and sad expressions. Our results show that there is a difference between high and low trait anxiety in the pre-attentive processing of facial expression. This suggests that personality traits are important factors influencing the pre-attentive processing of facial expressions, and high trait anxiety individuals may have difficulty in effectively distinguishing between happy and sad emotional faces during the pre-attentive processing stage and have similar processing patterns for them.
Subjects: Psychology >> Other Disciplines of Psychology submitted time 2021-05-30
Abstract： Abstract: Mild cognitive impairment (MCI) is an intermediate state between normal aging and dementia, and there is no high-quality evidence that supports the pharmacologic treatment of MCI. Repetitive transcranial magnetic stimulation (rTMS) can improve the whole brain function by eliciting changes in synaptic plasticity. In this systematic review, the effectiveness and neural mechanisms of rTMS enhance MCI patients were analyzed. Future studies should optimize the localization for TMS, extend the period of the intervention effect evaluation, and explore how rTMS works in the treatment of MCI combining with neuroimaging technologies.
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Awaiting Review
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