Manual card sorting compared to automatic card presentation for assessing visual lobe size

Abstract

Using a sample of 54 Hong Kong Chinese subjects a highly significant correlation was found between lobe area and search performance on a task where the stimulus presentation was controlled with a semi-automatic electro-mechanical ‘card changer’. By using the same stimulus material for determination of lobe size and search performance and by reducing the possibility of subjects using extreme search strategies, a 90s manual card sorting test was found to correlate significantly with the ‘card changer’ results and with lobe area. The good correlation with lobe area was obtained for a homogeneous group of subjects with respect to age and near acuity using a rapid and simple method of lobe area measurement. The visual lobe is a function of considerable importance for visual search and has been shown to be related to search performance in a variety of practical situations. It is suggested here that a card sorting task may be used to assess the relative extent of a person's visual lobe size for screening individuals involved in search tasks, or to assess the effects of training.     

Lateralization of the startle reflex circuit in humans: An examination with monaural probes following unilateral temporal lobe resection.

Startle reflex (SR) modulation elicited by monaural probes during affective picture viewing was investigated in patients following left temporal lobectomy (LTL; n = 8) and right temporal lobectomy (RTL; n = 10) and in controls (n = 18). All patients had undergone anteromedial temporal lobe (ATL) resection. LTL participants exhibited attenuated overall SR magnitude. Affective SR modulation in controls was significant for left ear probes, at both eyes, but not for right ear probes. RTL but not LTL participants displayed significant startle attenuation during pleasant picture viewing. Results suggest that monaural startle probes primarily activate structures in the ipsilateral ATL and that the ATLs are interconnected, with the left ATL more critical in perceiving arousing properties of affective stimuli, necessary for affective SR modulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Brain potentials implicate temporal lobe abnormalities in criminal psychopaths.

Psychopathy is associated with abnormalities in attention and orienting. However, few studies have examined the neural systems underlying these processes. To address this issue, the authors recorded event-related potentials (ERPs) while 80 incarcerated men, classified as psychopathic or nonpsychopathic via the Hare Psychopathy Checklist-Revised (R. D. Hare, 1991, 2003), completed an auditory oddball task. Consistent with hypotheses, processing of targets elicited larger frontocentral negativities (N550) in psychopaths than in nonpsychopaths. Psychopaths also showed an enlarged N2 and reduced P3 during target detection. Similar ERP modulations have been reported in patients with amygdala and temporal lobe damage. The data are interpreted as supporting the hypothesis that psychopathy may be related to dysfunction of the paralimbic system--a system that includes parts of the temporal and frontal lobes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

组合阵栅瓣抑制方法研究

随着水声探测频带延伸至低频/甚低频段,目前大孔径拖线阵声纳需要处理超过10倍频程的宽带信号.稀疏阵列虽能以较小系统工程代价获得足够窄的波束扫描宽度,但会产生严重的栅瓣效应,使弱目标检测变得困难.为了抑制强十扰的栅瓣效应对弱目标检测的影响,本文将MVDR方法应用于宽带组合阵处理,有效抑制了栅瓣模糊,扩展了处理频带.理论分析表明组合阵MVDR方法与CBF相比,具有显著的栅瓣抑制能力,通过仿真分析和海试数据分析验证了该方法的有效性.     

Recent advances in insect olfaction, specifically regarding the morphology and sensory physiology of antennal sensilla of the female sphinx moth Manduca sexta.

The antennal flagellum of female Manduca sexta bears eight sensillum types: two trichoid, two basiconic, one auriculate, two coeloconic, and one styliform complex sensilla. The first type of trichoid sensillum averages 34 microm in length and is innervated by two sensory cells. The second type averages 26 microm in length and is innervated by either one or three sensory cells. The first type of basiconic sensillum averages 22 microm in length, while the second type averages 15 microm in length. Both types are innervated by three bipolar sensory cells. The auriculate sensillum averages 4 microm in length and is innervated by two bipolar sensory cells. The coeloconic type-A and type-B both average 2 microm in length. The former type is innervated by five bipolar sensory cells, while the latter type, by three bipolar sensory cells. The styliform complex sensillum occurs singly on each annulus and averages 38-40 microm in length. It is formed by several contiguous sensilla. Each unit is innervated by three bipolar sensory cells. A total of 2,216 sensilla were found on a single annulus (annulus 21) of the flagellum. Electrophysiological responses from type-A trichoid sensilla to a large panel of volatile odorants revealed three different subsets of olfactory receptor cells (ORCs). Two subsets responded strongly to only a narrow range of odorants, while the third responded strongly to a broad range of odorants. Anterograde labeling of ORCs from type-A trichoid sensilla revealed that their axons projected mainly to two large female glomeruli of the antennal lobe.     

Evidence for intact semantic representations in patients with frontal lobe lesions.

Patients with frontal lobe lesions and control participants were assessed on 2 tests of semantic knowledge. In the triadic comparison task, participants were shown all possible triplets of 12 animal names and judged which 2 of each triplet were most alike. In the ordered similarity task, participants rank ordered animals in terms of their similarity to a target animal. For both tasks, semantic structure-- derived from multidimensional scaling techniques-- revealed similar representations in patients with frontal lobe lesions and control participants. Additional pathfinder analyses also produced networks that did not differ between groups. These patients exhibited intact semantic knowledge despite deficits on tests of free recall and verbal fluency that involved the same semantic category and exemplars. Thus, intact representation of semantic knowledge in frontal patients stands in contrast to their marked deficits in strategic retrieval of semantic knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

变齿距铣刀高速微铣削的动态特性及稳定性研究

在高速微铣削加工过程中,提高生产效率和零件质量的需求日益强烈,这使得机床一直在系统的动态稳定性极限附近工作,而机床颤振的存在是限制微铣削加工生产率的主要障碍.基于颤振稳定性的准确预测,能采取一些措施来提高动态稳定性极限,例如通过改变铣刀结构.提出了数值分析与铣削实验相结合的方法,采用变齿距微铣刀来研究铣削加工的动态特性和稳定性.另外提出了采用时域仿真的输出力来表征加工稳定性的新方法,采用变齿距铣刀可以非常有效地提高某些速度范围的颤振稳定性.对于选定刀具的加工,这种方法可以用于加工优化,或在设计阶段预测刀具新型结构的性能.     

Object-based inhibition of return in patients with posterior parietal damage.

Recent evidence has shown that inhibition of return, IOR, is impaired in patients with parietal damage with or without clinical signs of neglect (Bartolomeo, Sieroff, Decaix, & Chokron, 2001; Vivas, Humphreys, & Fuentes, 2003, respectively). In addition to environment-based IOR, Tipper et al. (1991) showed that IOR could be also associated with dynamic, object-based representations. In our study, we examined four patients with unilateral lesions to the parietal lobe, and a group of healthy controls, in an IOR procedure with moving objects where a pre-cued object could move, clockwise or counterclockwise, 90° in polar coordinates. The group of control participants showed a small but significant object-based IOR effect. In contrast, the patients showed an object-based IOR effect when the objects moved from the contralesional field toward the ipsilesional field, whereas there was no IOR effect when they moved from the ipsilesional to the contralesional field. These findings are discussed in terms of the role of the parietal cortex in implementing attentional biases in both environment-based (Vivas et al., 2003) and object-based frames of reference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于格理论的非均匀稀疏线阵旁瓣结构的分析方法

 在有限个阵元的情况下,非均匀稀疏线阵能得到更大的阵列孔径。但由于其是对空间信号的非均匀采样,不能通过常规的傅立叶变换方法求得其峰值旁瓣解析表达式。本文提出了一种基于格理论的非均匀稀疏线阵的旁瓣结构分析方法。首先建立了阵列流形格的数学模型并对其物理含义进行了仿真分析,然后推导了阵列流形格最近格点与峰值旁瓣的对应关系,从而将非均匀稀疏线阵峰值旁瓣结构分析问题转化为求距阵列流形格原点最近格点问题。该方法可以准确地确定非均匀稀疏线阵旁瓣中增益大于门限电平的旁瓣个数及其各自的方位。计算机仿真结果表明了该方法的有效性和准确性。     

高速车削加工颤振稳定域建模与验证

再生颤振是制约高速车削加工效率、加工质量和刀具寿命的主要因素。以高速车削加工为研究对象,建立了考虑再生效应的高速车削动态切削力模型和颤振稳定域解析模型;通过模态实验获得机床系统的频率响应函数,在此基础上综合使用车削稳定性判据进行数值分析,获得了车削颤振稳定域解析解;进行了车削颤振稳定性时域仿真,获得了车削过程的切削力和刀具动态位移。仿真实验结果与解析解吻合良好,验证了建立的车削颤振系统动力学模型和颤振解析模型的正确性。