Age difference in numeral recognition and calculation: an event-related potential study.

In this study, we investigated the age difference in numeral recognition and calculation in one group of school-aged children (n = 38) and one of undergraduate students (n = 26) using the event-related potential (ERP) methods. Consistent with previous reports, the age difference was significant in behavioral results. Both numeral recognition and calculation elicited a negativity peaking at about 170-280 ms (N2) and a positivity peaking at 200-470 ms (pSW) in raw ERPs, and a difference potential (dN3) between 360 and 450 ms. The difference between the two age groups indicated that more attention resources were devoted to arithmetical tasks in school-aged children, and that school-aged children and undergraduate students appear to use different strategies to solve arithmetical problems. The analysis of frontal negativity suggested that numeral recognition and mental calculation impose greater load on working memory and executive function in schoolchildren than in undergraduate students. The topography data determined that the parietal regions were responsible for arithmetical function in humans, and there was an age-related difference in the area of cerebral activation.     

情绪对学习不良青少年选择性注意和持续性注意的影响

以学习不良青少年为被试,采用成绩反馈法诱发情绪,考察了情绪对学习不良青少年选择性注意和持续性注意的影响,结果表明：（1）情绪会影响学习不良青少年的选择性注意,具有积极低唤醒情绪的学习不良青少年,他们的选择性注意的反应时显著短于消极情绪下的被试;(2)学习不良青少年的情绪会影响到他们的持续性注意能力,消极高唤醒的情绪能够增加虚报率,而积极高唤醒的情绪能够提高判断标准,降低虚报率     

结直肠癌诊断模式的若干思考

结直肠癌是常见的消化道恶性肿瘤,然而在临床上得到诊断时大多已经到了中晚期,错过了最佳的治疗时机.近年来,随着基因相关技术及生物信息技术的迅猛发展,结直肠癌诊断方法得到不断改进,但早期诊断仍不尽如人意.因此现有的诊断模式值得我们去深思,从哲学意义上探索更为完善的诊断模式.     

Chinese kindergartners’ automatic processing of numerical magnitude in Stroop-like tasks

Using Stroop-like tasks, this study examined whether Chinese kindergartners showed automatic processing of numerical magnitude. A total of 36 children (mean age 5 5 years 10 months) were asked to perform physical size comparison (i.e., “Which of two numbers is bigger in physical size?”) and numerical magnitude tasks (i.e., “Which of two numbers is bigger in numerical magnitude?”) on 216 number pairs. These number pairs varied in levels of congruence between numerical magnitude and physical size (for Stroop effect) and numerical distance (for distance effect). On the basis of analyses of response time and error rates, we found that Chinese kindergartners showed automatic processing of numerical magnitude. These results are significantly different from previous studies’ findings about the onset age (ranging from around the end of first grade to third grade) for automatic processing of numerical magnitude.     

The ameliorating effect of oroxylin A on scopolamine-induced memory impairment in mice

Oroxylin A is a flavonoid and was originally isolated from the root of Scutellaria baicalensis Georgi., one of the most important medicinal herbs in traditional Chinese medicine. The aim of this study was to investigate the ameliorating effects of oroxylin A on memory impairment using the passive avoidance test, the Y-maze test, and the Morris water maze test in mice. Drug-induced amnesia was induced by administering scopolamine (1 mg/kg, i.p.) or diazepam (1 mg/kg, i.p.). Oroxylin A (5 mg/kg) significantly reversed cognitive impairments in mice by passive avoidance and the Y-maze testing (P<.05). Oroxylin A also improved escape latencies in training trials and increased swimming times and distances within the target zone of the Morris water maze (P<.05). Moreover, the ameliorating effects of oroxylin A were antagonized by both muscimol and diazepam (0.25 mg/kg, i.p., respectively), which are GABA(A) receptor agonists. Furthermore, oroxylin A (100 microM) was found to inhibit GABA-induced inward Cl(-) current in a single cortical neuron. These results suggest that oroxylin A may be useful for the treatment of cognitive impairments induced by cholinergic dysfunction via the GABAergic nervous system.     

浅谈分子生物学与临床医学研究的结合

随着分子生物学理论和技术从基础研究渗透到临床各个学科,对临床诊断和治疗水平的提高起到了积极的推动作用。但在实际工作中还存在着发展不平衡以及认识与理解上的误区。就分子生物学与临床医学研究的相结合的现状、存在问题及相应对策,以及今后我国临床医学分子生物学研究的发展前景进行了较广泛深入的讨论。     

Eye-movement evidence of the time-course of attentional bias for threatening pictures in test-anxious students

Protocols for measuring attentional bias to threat in test-anxiety, a special form of trait-anxiety, are rarely found in the literature. In our eye-tracking study, we introduced a new protocol, and studied the time-course of attention to test-related pictures with varying threat levels in 22 high test-anxious (HTA) and 22 low test-anxious (LTA) subjects. To determine whether attentional bias to test-related pictures is due to test-anxiety and not to state-anxiety, we also included a third group of 22 subjects with high state-anxiety but low test-anxiety (HSA). The subjects completed a free viewing task (FVT) in which high threat-neutral (HT-N) and low threat-neutral (LT-N) picture pairs were presented for 3?s. The results demonstrated that: (1) HTA subjects showed initial orienting to LT pictures, early attentional engagement with HT pictures later on and avoidance of HT pictures at the very end; (2) LTA subjects showed initial orienting to HT pictures and maintenance of attention on them later on; while (3) HSA subjects showed an initial orientation towards LT pictures and maintenance of attention on LT and HT pictures later on. These results suggest that, (high) test-anxiety is also prone to attentional bias towards test-related threat stimuli. Implications for future research are discussed.     

Enhanced conflict-driven cognitive control by emotional arousal,not by valence

Emotion is widely agreed to have two dimensions, valence and arousal. Few studies have explored the effect of emotion on conflict adaptation by considering both of these, which could have dissociate influence. The present study aimed to fill the gap as to whether emotional valence and arousal would exert dissociable influence on conflict adaptation. In the experiments, we included positive, neutral, and negative conditions, with comparable arousal between positive and negative conditions. Both positive and negative conditions have higher arousal than neutral ones. In Experiment 1, by using a two-colour-word Flanker task, we found that conflict adaptation was enhanced in both positive and negative contexts compared to a neutral context. Furthermore, this effect still existed when controlling stimulus–response repetitions in Experiment 2, which used a four-colour-word Flanker task. The findings suggest emotional arousal enhances conflict adaptation, regardless of emotional valence. Thus, future studies should consider emotional arousal when studying the effect of emotion on conflict adaptation. Moreover, the unique role of the emotional context in conflict-driven cognitive control is emphasised.     

Age-Related Differences in Metamemory Accuracy among the Elderly: The Effect of Declining Inhibitory Function

To explore the age-related difference in metamemory accuracy during older adulthood, we measured the metamemory calibration and resolution of older participants. In Study 1, we divided the participants into four groups by age: 60–64, 65–69, 70–74, and above 75 years. We used young adults as a contrast group. The results revealed the inconsistency of age-related differences in calibration and resolution. The young adults had higher calibration in global prediction than the four groups of older adults before the study, whereas there were no differences among the four elderly groups. There were no differences in resolution between the 60- to 64-year, 65- to 69-year and young adult groups, but these three groups had higher resolution than the 70- to 74-year and above 75-year groups for item-by-item prediction. In Study 2, we measured the older participants’ inhibitory function to explore whether impaired inhibitory function led to a decline in metacognitive ability in the elderly. The results showed that the inhibition function was highly correlated with the accuracy of judgments of learning (JOL) and can predict the accuracy of JOL to a certain extent.     

A study of artificial eyes for the measurement of precision in eye-trackers

The precision of an eye-tracker is critical to the correct identification of eye movements and their properties. To measure a system’s precision, artificial eyes (AEs) are often used, to exclude eye movements influencing the measurements. A possible issue, however, is that it is virtually impossible to construct AEs with sufficient complexity to fully represent the human eye. To examine the consequences of this limitation, we tested currently used AEs from three manufacturers of eye-trackers and compared them to a more complex model, using 12 commercial eye-trackers. Because precision can be measured in various ways, we compared different metrics in the spatial domain and analyzed the power-spectral densities in the frequency domain. To assess how precision measurements compare in artificial and human eyes, we also measured precision using human recordings on the same eye-trackers. Our results show that the modified eye model presented can cope with all eye-trackers tested and acts as a promising candidate for further development of a set of AEs with varying pupil size and pupil–iris contrast. The spectral analysis of both the AE and human data revealed that human eye data have different frequencies that likely reflect the physiological characteristics of human eye movements. We also report the effects of sample selection methods for precision calculations. This study is part of the EMRA/COGAIN Eye Data Quality Standardization Project.