Auditory and visual semantic priming using different stimulus onset asynchronies: An event-related brain potential study

Semantic priming effects (behavioral and electrophysiological) were compared in the visual and auditory modalities across three stimulus onset asynchronies (SOAs; 0, 200, and 800 ms). When both prime and target were presented in the visual modality (the prime just to the left of a fixation point and the target to the right) there were N400 priming effects present across the three SOAs. However, the N400 in the 0-ms SOA condition extended longer in time (800 vs. 500 ms) than in the other SOAs. When both the prime and target were presented in the auditory modality (the prime to the right ear and the target to the left), the largest priming effects were found for the 800-ms SOA. Moreover, there was a relatively early priming effect present in the 0- and 800-ms SOA conditions but not in the 200-ms condition. The results are discussed in terms of modality differences in the time course of word comprehension processes.     

Sexual Content-Induced Delay With Double-Entendre Words

Seventy-three men and 72 women made lexical decisions to target words that followed sentences constructed so that the last word was a sexual double-entendre. Prime target relatedness, erotic versus nonerotic target, stimulus onset asynchrony, and participant's gender were varied in a between-subjects design. A second analysis that substituted sentence context for prime target relationship also was conducted. Data were collected on the emotionality and social acceptability of priming sentences and target words. Results revealed that, as with previous research on neutral words, prime target relatedness facilitated lexical decisions. Additionally, there was evidence of slowing in making lexical decisions when erotic material was presented or was part of a contextual bias. This delay was accentuated in women. A model that proposes that sexual words evoke a more complex processing sequence is presented. The model suggests that appraisal and checking or editing mechanisms, which are accentuated in women, help explain the phenomenon. Portions of this work was submitted by the junior author in partial fulfillment of the requirements for Honors in Psychology at Louisiana State University     

Attentional Bias in Posttraumatic Stress Disorder

This study investigated preferential encoding of threat material in subjects with posttraumatic stress disorder (PTSD) with a modified dot-probe paradigm. This paradigm indexes attentional bias by measuring response latency to name neutral target words that are presented adjacent to or distant from threat words. Motor vehicle accident survivors with PTSD (n = 15), subclinical PTSD (n = 15), and low anxiety (n = 15) were required to name target words that were presented either adjacent to or distant from strong threat, mild threat, positive, and neutral words. PTSD subjects named targets faster when they were in close proximity to mild threat words. Results suggested that PTSD subjects' attention was drawn to the mild threat stimuli and are discussed in the context of network models of PTSD.     

An effect of triazolam on visual attention and information processing

This study explored whether benzodiazepines selectively affect aspects of attention and/or visual information processing, as they do memory. A cued visual-search paradigm was employed, using normal volunteers and a single dose of triazolam. This paradigm provided for a detailed examination of two aspects of visual attention and information processing: 1) controlled versus automatic attention allocation (via central and peripheral cues), and 2) the extent to which processing an item in a non-cued location affects performance (via cue-validity). Triazolam, compared to placebo, significantly increased response time, and Drug Condition interacted with Cue-Validity but not Cue-Type. Based on these data, we argue that triazolam doesnot affect attention allocation butdoes affect attentional disengagement and/or attention switching mechanisms.     

喉部CT仿真内窥镜成像技术的探讨

目的：探讨喉部CT仿真内窥镜(CT virtual endoscopy，CTVE)的成像质量及其影响因素。方法：对84例喉部螺旋CT扫描者行CTVE成像，根据喉腔内部结构、病灶、黏膜皱襞的显示情况和有无伪影将CTVE图像分为3级，分别比较CTVE技术在不同的扫描层厚、重建层厚及阈值的情况下图像质量的优劣。结果：CT原始扫描层厚为2mm、3mm分别与5mm、8mm的CTVE图像质量相比较，有显著性差异(P＜0．05)；重建层厚为2mm、3mm与5mm相比较，均有显著性差异(P＜0．05)；阈值为 -800— -600HU与阈值为-300HU相比较，有显著性差异(P＜0．05)。结论：不同的CT原始扫描层厚、重建层厚及阈值对CTVE图像的质量影响有明显差异。选用合适的原始扫描参数及重建参数，可以提高CTVE图像的质量，对喉部疾病的诊断很有帮助。     

中医舌象计算机识别研究的现状分析

从静态舌图像计算机识别研究的关键环节出发,对当前的研究现状进行了分析.认为在舌图像的采集方面有必要引入正交设计、图像质量评价等方法以筛选出高标准、统一、实用的图像采集条件;图像分割研究可以考虑从多角度入手,综合使用多种分割方法,取长补短,以提高分割效果;同时采用Delphi评价法、多中心的网上专家判别等手段,大样本集中专家经验,综合各家的辨舌经验,建立科学规范的舌象诊断标准;当前舌象识别研究的热点主要集中在舌的颜色领域,研究的方向有待向颜色以外的其他方面拓展,并最终由定性向定量转化,而实现舌诊内容的综合判别将是今后努力的方向.     

云纹技术在断裂分析中的应用

改进了传统的云纹数据处理方法,提出用曲面拟合方法处理云纹数据,提高了计算机处理云纹数据的效率与质量。又提出用云纹法测量J积分的技术,可望解决实际工程构件的J积分测量问题。     

中医美容多媒体查询系统的数据库设计

将中医美容知识的查询系统与多媒体技术结合，使用ＦｏｘＰｒｏｆｏｒＷｉｎｄｏｗｓ完成查询系统的主要设计思想。设计思想包括数据库设计、查询设计、图像处理和菜单设计４个方面。     

Pulsed magnetization transfer spin-echo MR imaging

Cross relaxation between macromolecular protons and water protons is known to be important in biologic tissue. In magnetic resonance (MR) imaging sequences, selective saturation of the characteristically short T2 macromolecular proton pool can produce contrast called magnetization transfer contrast, based on the cross-relaxation process. Selective saturation can be achieved with continuous wave irradiation several kilohertz off resonance or short, intense 0° pulses on resonance. The authors analyze 0° binomial pulses for T2 selective saturation, present design guidelines, and demonstrate the use of these pulses in spin-echo imaging sequences in healthy volunteers and patients. Using the phenomenologic Bloch equations modified for two-site exchange, the authors derive the analytic expressions for water proton relaxation under periodic pulsed saturation of the macromolecular protons. This relaxation is shown to be monoexpo-nential, with a rate constant dependent on the saturation pulse repetition rate and the individual and cross-relaxation rates.