Some Guidelines for the Use of Stimulus Modifications in Teaching Response Topography to People with Developmental Disabilities

The use of stimulus modifications in teaching involves altering the materials of a task in order to simplify its execution. Though their use in teaching stimulus discriminations to people with developmental disabilities has been extensively investigated, less attention has been given to their utilization in teaching response topography. This paper offers some general guidelines about their use for this purpose. In relation to their design, it is suggested that the aim should be to reduce the demands made by task components, to eliminate components, and/or to increase the attentional value of the discriminating features of the response topography. In relation to their application, guidelines are suggested about when they should be employed in conjunction with response prompts; when they should be used, either alone or in conjunction with response prompts, in preference to response prompts alone; whether one or a series of modifications is required; and at what point during teaching should probe trials on the unmodified task be introduced.     

2000只近视眼角膜表面形态及屈光参数的检测分析

目的 :探讨近视眼的角膜表面形态及屈光参数的变化规律。方法 :用电脑验光仪及计算机辅助的角膜地形图仪为 2 0 0 0只近视眼 (分为低度、中度、高度、超高度 4组 )行验光及角膜摄像分析。以 2 82只正视眼作对照组。结果 :低度、中度、高度及超高度组角膜表面形态近圆形 (圆形及椭圆形 )分别为 2 8.39% ,2 7.73% ,2 8.0 4 % ,2 0 .0 8% ,低于正视组的 4 1.6 8% (P<0 .0 5 ) ;领结形 (对称及非对称领结形 )分别为6 5 .5 1% ,6 5 .91% ,6 4.87% ,72 .32 % ,高于正视组的 5 2 .0 7% (P <0 .0 5 ) ;角膜表面规则指数 (SRI)明显高于正视组 ;角膜表面不规则指数 (SAI)与正视组差异无显著性 (P >0 .0 5 ) ;平均角膜屈光度 (ACP)和散光度(CYL)显著大于正视组 (P <0 .0 5 )。结论 :近视眼角膜表面形态及屈光参数较正视眼有明显变化。LASIK术前详细分析角膜地形图为设计个性化手术方案及预测疗效提供了重要依据。     

翼状胬肉术后的角膜地形图改变

目的 评价翼状胬肉术前术后的角膜屈光状态及其与术前胬肉大小的关系，探讨胬肉手术的时机与必要性。方法 对29例(32只眼)翼状胬肉患者进行胬肉侵入角膜的长度测量，并于术前术后行角膜地形图检测，以资对比。结果 32只眼均有程度不同的顺规散光，其大小与翼状胬肉侵入角膜的长度有关。手术显著降低了角膜散光，提高了角膜平均屈光力。手术导致的角膜散光变化、角膜平均屈光力变化和术前胬肉大小显著相关。结论 翼状胬肉的生长和手术切除对角膜的屈光状况有显著影响，胬肉越大，这种影响就越大。当胬肉较大时，角膜地形图的改变可能包括一部分假象。     

ABNORMAL CORNEAS MEASURED BY A NEW PHOTOGRAMMETRIC TECHNIQUE

The limitations of keratometry and photokeratoscopy are briefly discussed. A new photogrammetric technique of measuring corneal topography is described. Contours and cross-sections of abnormal corneas are presented to illustrate the scope and application of the new technique.     

Responses of human primary sensorimotor and supplementary motor areas to internally triggered unilateral and simultaneous bilateral one‐digit movements. A high‐resolution EEG study

We modelled the responses of human primary sensorimotor areas and supplementary motor area to simple, self-initiated unilateral and simultaneous bilateral middle finger movements using a novel high-resolution electroencephalography technology. The results support the view that these cortical motor areas are involved in parallel and present similar activity in the preparation, initiation, and execution of the contralateral and bilateral movements. Furthermore, the left primary sensorimotor area (dominant hemisphere) appears to be activated more than the right primary sensorimotor area during the preparation and performance of the ipsilateral movements.     

Normal and regenerating optic fibers in goldfish tectum: HRP-EM evidence for rapid synaptogenesis and optic fiber-fiber affinity

The distribution of normal and regenerating retinal fibers and synapses was studied on tectum in goldfish by light (LM) and electron microscopy (EM). Since labeling of the early regenerating fibers was previously reported to be difficult, a new 'cold-fill' HRP labeling protocol was developed, which labeled regenerating optic fibers and terminals on tectum as early as 14 days after nerve crush when they first arrive on tectum. In order to characterize the laminar distribution of optic afferents in normal fish and in fish regenerating for 14-240 days, EM photomontages of areas 14 microns wide by 160 microns deep through the HRP-labeled primary optic innervation layer (S-SO-SFGS) were constructed. The time points in regeneration that were examined spanned the period in which others have shown that an initially diffuse retinotopic map becomes spatially restricted. At the LM level regenerating optic fibers were restricted to the optic lamina. They reinnervated tectum in an anterior to posterior sequence as previously seen with autoradiography. In addition, at 14 days, some "pioneer" optic fascicles were found to have already grown to posterior tectum where they gave rise to branches with boutonlike terminations and growth-cone-like processes. Form the ultrastructural analysis it was clear that optic fibers and terminals observed strict laminar boundaries as they partitioned themselves in the optic laminae (S, SO and SFGS) in both normal and regenerating fish. The behavior of optic fibers was lamina specific with respect to synapse formation and the orientation of fiber outgrowth. As early as 14 days regeneration, optic fibers made synapses onto the four types of postsynaptic profiles observed in normal fish. Numerous optic terminals were labeled at 14 days, and there appeared to be no waiting period between fiber ingrowth to the SO and synapse formation in the S and SFGS. At 14-60 days, atypical synaptic contacts which appear to be nascent synapses were made by labeled optic fibers in fascicles and by growth-cone-like processes. By 21-30 days, the density of optic terminals was high and there were many more fasciculated optic fibers in the SFGS than normal as late as 350 days. These findings suggest that optic fiber lamination is highly constrained by tectal cues, that fibers rapidly regenerate many synaptic terminals before retinotopic map refinement is complete, and that fibers have a strong affinity for each other.     

Neurophysiological and psychological predictors of genetic risk for schizophrenia

Mathematical genetic analyses were performed on a sample of schizophrenic families (25 probands and 58 first-degree relatives). Heritability coefficients were estimated for EEG power spectrum parameters and their topography, and also for psychological test data on thought and speech process disorder, designed to assess altered selectivity in cognitive activity. Multiple regression equations for genetic counseling regarding the prognosis of mental illness were derived from the neurophysiological and psychological measures.     

Cadaveric topography and morphometry of the vermiform appendix

Our study justified by the frequency of acute appendicitis and the possibility of anatomic variations of the caecoappendicular area attempt to index the topographic variations of the vermiform appendix (v.a.). On 80 fresh native cadavers (62 men and 18 women) without surgical antecedent whose mean age was 36 years (range between 16 and 78 years) we note the morphotype and the height. More over we study the intraperitoneal projection of the Mac Burney point, topography and shape of the cecum and the situation, shape and dimensions of the v.a. We note also the level of implantation of this latter on the cecum, appearance of the mesoappendix and the distance separating the base of the appendix to the ileo-caecal junction. Mac Burney's point permitted to localize appendix in 66%; the cecum has more often than not the form of a bulb (98.7%) and sited in right fossa iliaca. We noted 7 types of topographic disposition; front varieties were more frequent (68.7%) notably the pelvic direction (51.2%) with a medial (72.5%) or a posteromedial (27.5%) establishment on the cecum. The v.a. was more often in the form of worm with a long mesoappendix; his mean length was 106.4 mm (between 65 and 160 mm) and the mean diameter 6.77 mm (range between 4 and 10 mm). The distance which separated the base of the appendix to the ileo-cecal junction varied between 15 to 40 mm with a mean distance of 24.2 mm. Thus in this study, dimensions of the v.a. were very variables. Located in right fossa iliaca he adopted a front topography with pelvic direction and medial establishment on bulbar cecum. In spite of scarcity of ectopic situation of the appendix for which laparoscopic approach is salutary, a similar topographic study during surgical treatment of acute appendicitis will be interesting.     

正视眼角膜表面形态和屈光力分析

目的：为探讨正视眼角膜表面形态和屈光力。方法：８３只正视眼用ＴｏｍｅｙＴＭＳ－２ＴＭ型角膜地形图检查角膜表面形态和屈光力。结果：①绝对等级全角膜有２～５种颜色，屈光力有轻微的变化；②角膜中央屈光力为４３．８５４±１．３２１Ｄ，Ｓｉｍｋ值为４４．１４２±１．３４２Ｄ，平均屈光力（ＡＣＰ）为４３．００７±１．４７３Ｄ，角膜表面规则系数（ＳＲＩ）为０．２４１±０．２１３，角膜表面不对称系数（ＳＡＩ）为０．３２１±０．１３０，不规则散光指数（ＩＡＩ）为０．３５７±０．００６。结论：本文检查的国人正视眼角膜表面形态和屈光力数值，可为屈光性角膜手术提供解剖依据。     

Maturational topography of the visual evoked potential in fetal lambs

The normal maturational course of the visual evoked potential (VEP) in human newborns and infants is well documented. Unfortunately, there is a paucity of data about VEP maturation in the normal preterm infant. Since this population is at risk to develop many abnormalities affecting the VEP (intraventricular hemorrhage, hydrocephalus, and retinopathy of prematurity), one must question whether such VEP data collected from this group is representative of normal maturation. To provide normative parametric developmental data we have been studying VEP development in fetal lambs. Six fetal lambs between 105 and 120 days gestational age were externalized and surgically instrumented with subcutaneous recording electrodes placed over the occipital and parietal regions. High-intensity light-emitting diodes (LEDs) externalized fiberoptic cables were secured adjacent to the orbit. from 108 to 141 days gestation, fetal VEPs were recorded in response to bright flash stimulation and the maturational topography was investigated.Over the occipital regions, the emergence of major positivities at P400 and P650 were observed beginning around 120 days gestation. Over the parietal area, the emergence of P200 and P500 components was observed by 128 days gestation. The latency-maturation functions revealed that the slope of the parietal function was steeper than the occipital counterpart, suggesting that the maturation of parietal neurons occurs at a faster rate than neuronal development in the occipital regions.