Primary tumors of the nervous system in the light of an epidemiologic analysis

On a territory of 5 districts of western Poland with 3.097 thousands of inhabitants the annual incidence rates per 100 thousands of population as well as the prevalence rates of primary neoplasms have been determined. The results of our investigation have shown that multiforme glioblastomas and astrocytomas occurred in the investigated population with the highest annual incidence rates, whereas the highest prevalence rates were found for hypophyseal adenomas, to be followed by astrocytomas, meningiomas and glioblastoma multiforme. The obtained results are critically discussed and compared with epidemiological data presented by other authors who based on records from neurosurgical departments and autoptic sections, it is concluded that the presented results do reflect objectively the epidemiological situation of Poland.     

Results of nuclear medical, electroencephalographic, and angiographic examinations after brain tumor operations]

The methods of nuclear medicine and electro-encephalography allow, in combination, in almost every case the answer to the question of the cerebral tumour relapse. Our evaluation confirms the discovery of the greater sensitivity of the isotopic methods with relapses of glioblastomas, while relapses of meningiomas, astrocytomas, oligodendrogliomas and spongioblastomas can be recognized more frequently only by electro-encephalographic methods. The value of angiography is limited in cases of cerebral tumour relapses without pathological vascularisation, since the swelling can spread in the resection cavity without retroaction on the surrounding areas. For this reason vascular displacement (an only be observed very late on. Clinical judgement is furthermore complicated by the fact that after the removal of the primary tumour, often no reposition of the arteries ensues. After our exainations, a negative angiographic condition can be rule out a diagnosis of a relapse which has been established by electro-encephaolographic and isotopic methods.     

肺动脉血栓栓塞症与凝血纤溶系统失衡

在生理状态下,凝血与纤溶处于动态平衡状态;当这种平衡失衡时,便可招致出血不止或形成栓塞。体内某些抗凝途径的蛋白缺陷会使机体处于高凝状态而导致静脉血栓栓塞性疾病(VTE),已经报道有多种栓塞因素与VTE的发生有关;人们通常认为,慢性栓塞性肺动脉高压(CTE-PH)是静脉系统栓子反复脱落至肺动脉所致,很自然的会想到CTE-PH的发病可能与以上多种栓塞因素有关,然而,目前研究更倾向于CTEPH和VTE并没有直接的关系或者说是两个独立的疾病。     

Relative absence of neuropsychological deficit in patients with low grade astrocytomas

Given the current accuracy and precision of modern brain imaging technology, there is presumed to be little utility in neuropsychological assessment procedures in patients with brain tumors. The primary exposure of many clinical neuropsychologists to patients with brain tumors is during their training, in the form of didactic classroom activities, such as reviewing the brain tumor cases of early investigators in the field. Historically, these brain tumors were the more aggressive and destructive tumors, such as grade III and IV astrocytomas, that could be identified with pre CT and pre MRI technology. With current imaging technology, low grade tumors that might previously have gone undiagnosed for years can be detected and patients followed over time. This series of cases represents documentation of the very unique neuropsychological status of patients with relatively slow growing, infiltrative brain tumors classified as grade II astrocytomas. The potential relevance of neuropsychological assessment for such cases is discussed.     

Attention-based texture segregation

Luminance- or color-defined +/- 45 degrees-oriented bars were arranged to yield single-feature or double-conjunction texture pairs. In the former, the global edge between two regions is formed by differences in one attribute (orientation, or color, or luminance). In the color/orientation double-conjunction pair, one region has +45 degrees red and -45 degrees green textels, the other -45 degrees red and +45 degrees green textels (the luminance/orientation double-conjunction pair is similar); such a pair contains a single-feature orientation edge in the subset of red (or green) textels, and a color edge in the subset of +45 degrees (or -45 degrees) textels. We studied whether edge detection improved when observers were instructed to attend to such subsets. Two groups of observers participated: in the test group, the stimulus construction was explained to observers, and they were cued to attend to one subset. The control group ran through the same total number of sessions without explanations/cues. The effect of cuing was week but statistically significant. Feature cuing was more effective for color/orientation than for luminance/orientation conjunctions. Within each stimulus category, performance was nearly the same no matter which subset was attended to. On average, a global performance improvement occurred over time even without cuing, but some observers did not improve with either cuing or practice. We discuss these results in the context of one-versus two-stage segregation theories, as well as by reference to signal enhancement versus noise suppression. We conclude that texture segregation can be improved by attentional strategies aimed to isolate specific stimulus features.     

Free-operant forgetting: Delayed stimulus control of multiple-schedule performance

Pigeons' responses were reinforced in two components of several multiple variable-interval variable-interval schedules of food reinforcement. In one component, the key was illuminated green for 15 seconds and white for 45 seconds. In the other component, the key was illuminated red for 15 seconds and white for 45 seconds. Values for the exponent of the power functions relating response ratios to reinforcement ratios were higher in the presence of the discriminative stimuli (green or red) than in the presence of white. Sensitivity of response ratios to changes in reinforcement ratios provided an index of the extent to which responding was under delayed stimulus control by prior discriminative stimuli.     

Experiments in micro-history: Attributions about the recent vs. the remote subjective past

Demonstrated in two studies ( N = 64, N = 79) that information about a hypothetical stimulus person that appears to be 3 hold is judged more positively than information that appears to be 45 min old (p < .03, p < .007 respectively). In both instances, the information was received 1½ hago, but by unobtrusively manipulating the speeds of a clock by a factor of two, subjects were led to believe that they received the information either 45 min or 3 hago. The implications of thefindings for theories of attribution and social judgment are pointed out.     

Personality traits in women with Turner syndrome

Turner syndrome is caused by the total or partial absence of, or structural abnormalities in, one sex chromosome. A personality style characterized by traits related to low neuroticism and high extroversion has been reported for females with Turner syndrome, indicating possible genetic factors related to personality development. This study examines personality traits in 37 Swedish women with Turner syndrome using the Karolinska Scales of Personality Inventory. Compared to reference data, the subjects rated themselves as more sensation seeking, less detached, less verbally aggressive and less irritated. These results partially support previous findings. The subjects were divided into three karyotype groups: 45,X (n = 13), 45,X/46,XX or 45,X/45,XY (n = 13), and structural abnormalities (n = 11). Contrary to some previous findings, no differences in personality were found between the karyotype groups.     

Burnout and risk of cardiovascular disease: evidence, possible causal paths, and promising research directions

Burnout is characterized by emotional exhaustion, physical fatigue, and cognitive weariness, resulting from prolonged exposure to work-related stress. The authors review the accumulated evidence suggesting that burnout and the related concept of vital exhaustion are associated with increased risk of cardiovascular disease and cardiovascular-related events. The authors present evidence supporting several potential mechanisms linking burnout with ill health, including the metabolic syndrome, dysregulation of the hypothalamic-pituitary-adrenal axis along with sympathetic nervous system activation, sleep disturbances, systemic inflammation, impaired immunity functions, blood coagulation and fibrinolysis, and poor health behaviors. The association of burnout and vital exhaustion with these disease mediators suggests that their impact on health may be more extensive than currently indicated.     

Stimulus selection in passive avoidance learning and retention: weanling, periadolescent, and young adult rats

Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.     

Large continuous perspective transformations are necessary and sufficient for accurate perception of metric shape

We investigated the ability to perceive the metric shape of elliptical cylinders. A large number of previous studies have shown that small perspective variations (< or =10 degrees) afforded by stereovision and by head movements fail to allow accurate perception of metric shape. If space perception is affine (Koenderink & van Doom, 1991), observers are unable to compare or relate lengths in depth to frontoparallel lengths (i.e., widths). Frontoparallel lengths can be perceived correctly, whereas lengths in depth generally are not. We measured reaches to evaluate shape perception and investigated whether larger perspective variations would allow accurate perception of shape. In Experiment 1, we replicated previous results showing poor perception with small perspective variations. In Experiment 2, we found that a 90 degrees continuous change in perspective, which swapped depth and width, allowed accurate perception of the depth/width aspect ratio. In Experiment 3, we found that discrete views differing by 90 degrees were insufficient to allow accurate perception of metric shape and that perception of a continuous perspective change was required. In Experiment 4, we investigated continuous perspective changes of 30 degrees, 45 degrees, 60 degrees, and 90 degrees and discovered that a 45 degrees change or greater allowed accurate perception of the aspect ratio and that less than this did not. In conclusion, we found that perception of metric shape is possible with continuous perspective transformations somewhat larger than those investigated in the substantial number of previous studies.     

Perceived path of oblique motion: horizontal-vertical and stimulus-orientation effects

Subjects adjusted the path of moving stimuli to produce apparent slopes of 45 degrees with respect to horizontal. The stimulus was either a single moving dot or a vertical or horizontal bar. In separate experiments either the stimuli were tracked or fixation was maintained on a stationary fixation target positioned 8 deg to the right of the center of stimulus motion. In both experiments the selected path slopes were in general more horizontal than 45 degrees. This pattern indicates that subjects overestimate the vertical component of motion along an oblique path, and is interpreted as a manifestation of the spatial anisometropy generally termed the 'horizontal-vertical illusion'. Additionally, paths selected for horizontal bars were more vertical than those for vertical bars. This finding is interpreted in the context of a previous report of the influence of stimulus orientation on perceived velocity.     

A correlation between sickness or injury within two weeks,chronic diseases and fatigue among adults aged 18–45 years

To investigate the prevalence of fatigue, the relationship between sickness or injury within two weeks, chronic diseases and fatigue among adults aged 18–45 years. Thousand five hundred and seventy nine individuals were included in this cross-sectional study. The Chalder Fatigue Scale (CFS) was used to assess fatigue defined as CFS score ≥4. The prevalence of fatigue was 25% in this study. Our results showed that only sickness or injury within two weeks (odds ratio [OR]: 2.440) and chronic diseases (OR: 1.727) were significantly related to fatigue. Moreover, their ORs for fatigue remained the same in all models (binary logistic regression models with adjusting for demographic and health-related characteristics one by one). In conclusion, fatigue was prevalent among adults aged 18–45 years. Sickness or injury within two weeks and chronic diseases were the risk factors for fatigue independent of demographic and health-related characteristics.     

Some temporal properties of behavioral contrast

Pigeons were rewarded on a variable time interval for pecking a translucent key illuminated with either a 45 degrees or a vertical line. The key illumination changed every 2 min during daily 1-hr sessions. When the rates of pecking were stable, reinforcement was omitted in the presence of the 45 degrees line. Responding in the presence of the vertical line increased. This increase did not disappear when responses to the 45 degrees line were once more reinforced, but when reinforcements for responses in the presence of the 45 degrees line were again omitted, responding to the vertical line increased again. After the second alternation of these two procedures, the increased responding to the vertical line appeared when responses were not reinforced in the presence of the 45 degrees line, and disappeared when reinforcement was available during both stimuli. In a second experiment, the key illumination changed between sessions only, so that 1-hr sessions of reinforcement and non-reinforcement occurred on alternate days. Responding to the vertical line still increased when responding to the 45 degrees line was not reinforced, but the increase tended to disappear during the session.     

Pilocarpine seizures cause age-dependent impairment in auditory location discrimination

Children who have status epilepticus have continuous or rapidly repeating seizures that may be life-threatening and may cause life-long changes in brain and behavior. The extent to which status epilepticus causes deficits in auditory discrimination is unknown. A naturalistic auditory location discrimination method was used to evaluate this question using an animal model of status epilepticus. Male Sprague-Dawley rats were injected with saline on postnatal day (P) 20, or a convulsant dose of pilocarpine on P20 or P45. Pilocarpine on either day induced status epilepticus; status epilepticus at P45 resulted in CA3 cell loss and spontaneous seizures, whereas P20 rats had no cell loss or spontaneous seizures. Mature rats were trained with sound-source location and sound-silence discriminations. Control (saline P20) rats acquired both discriminations immediately. In status epilepticus (P20) rats, acquisition of the sound-source location discrimination was moderately impaired. Status epilepticus (P45) rats failed to acquire either sound-source location or sound-silence discriminations. Status epilepticus in rat causes an age-dependent, long-term impairment in auditory discrimination. This impairment may explain one cause of impaired auditory location discrimination in humans.     

Time-dependent recovery of taste aversion learning by fetal brain transplants in gustatory neocortex-lesioned rats.

We recently showed that fetal brain transplants produced a significant recovery in the ability of gustatory neocortex-lesioned rats to learn a conditioned taste aversion. In this report we assessed the capability of gustatory neocortex fetal brain transplants to produce behavioral recovery at different times. Four groups of male Wistar rats showing disrupted taste aversions due to gustatory neocortex lesions were studied. The lesioned animals received fetal cortical grafts, obtained from 16-day-old fetuses, and were retrained in the behavioral procedure after 15, 30, 45, or 60 days postgraft. Behavioral results showed a very good functional recuperation at 60 days, slight recovery at 45 and 30 days, and a poor recovery at 15 days postgraft. Results with HRP histochemistry revealed that at 30, 45, and 60 days postgrafting there were increased connections with the ventromedial nucleus of the thalamus and with the amygdala. At 15 days postgrafting there was an absence of HRP-labeled cells. In addition, behavioral recovery was correlated with increased acetylcholinesterase activity, detected histochemically, and with morphological neuronal maturation, revealed by Golgi staining. These results suggest that morphological maturity and reconnectivity between grafts and host tissue are important for behavioral recovery in gustatory neocortex-lesioned rats.     

光栅朝向分辨学习中存在关于45°对角线对称的镜像迁

采用光栅朝向分辨任务来探讨视知觉学习中是否存在关于45°对角线对称的镜像迁移现象。训练被试分辨15°或75°朝向3或5天,每天约1小时,训练前后测量15°、75°、45°朝向的分辨阈值。通过训练,训练朝向（15°或75°）的阈值下降,该学习效应没有迁移至45°朝向,但基本迁移到关于45°对称的朝向（75°或15°）上。这提示,视知觉学习可能发生在中间视皮层,该皮层同时具有一定的朝向特异性和关于45°对角线对称的镜像迁移性     

Zollner错觉的阈限测定

该研究选取大学生为被试,采用最小变化法,分别测量了干扰线对数、干扰线与主线之间的间隔、主线之间的间隔等三个变量导致Z?llner错觉产生的绝对阈限。每个变量中主线与水平面的夹角分为45°和90°两种条件。结果发现,若要产生Z?llner错觉：1）干扰线对数的阈限分别为5对、7对;2）干扰线与主线之间的间隔阈限分别为6.58像素、4.48像素,3）干扰线之间的间隔阈限分别为124.44像素、131.73像素。此外还发现：4）在Z?llner错觉形成的影响因素中,从大到小依次是：干扰线对数、主线之间的间隔、干扰线与主线之间的间隔;5）45°情况下比90°情况下更容易产生错觉;6）在Z?llner错觉知觉中,期望误差严重。     

What artificial grammar learning reveals about the neurobiology of syntax

In this paper we examine the neurobiological correlates of syntax, the processing of structured sequences, by comparing FMRI results on artificial and natural language syntax. We discuss these and similar findings in the context of formal language and computability theory. We used a simple right-linear unification grammar in an implicit artificial grammar learning paradigm in 32 healthy Dutch university students (natural language FMRI data were already acquired for these participants). We predicted that artificial syntax processing would engage the left inferior frontal region (BA 44/45) and that this activation would overlap with syntax-related variability observed in the natural language experiment. The main findings of this study show that the left inferior frontal region centered on BA 44/45 is active during artificial syntax processing of well-formed (grammatical) sequence independent of local subsequence familiarity. The same region is engaged to a greater extent when a syntactic violation is present and structural unification becomes difficult or impossible. The effects related to artificial syntax in the left inferior frontal region (BA 44/45) were essentially identical when we masked these with activity related to natural syntax in the same subjects. Finally, the medial temporal lobe was deactivated during this operation, consistent with the view that implicit processing does not rely on declarative memory mechanisms that engage the medial temporal lobe. In the context of recent FMRI findings, we raise the question whether Broca’s region (or subregions) is specifically related to syntactic movement operations or the processing of hierarchically nested non-adjacent dependencies in the discussion section. We conclude that this is not the case. Instead, we argue that the left inferior frontal region is a generic on-line sequence processor that unifies information from various sources in an incremental and recursive manner, independent of whether there are any processing requirements related to syntactic movement or hierarchically nested structures. In addition, we argue that the Chomsky hierarchy is not directly relevant for neurobiological systems.     

Aging preserves the ability to perceive 3D object shape from static but not deforming boundary contours

A single experiment investigated how younger (aged 18-32 years) and older (aged 62-82 years) observers perceive 3D object shape from deforming and static boundary contours. On any given trial, observers were shown two smoothly-curved objects, similar to water-smoothed granite rocks, and were required to judge whether they possessed the "same" or "different" shape. The objects presented during the "different" trials produced differently-shaped boundary contours. The objects presented during the "same" trials also produced different boundary contours, because one of the objects was always rotated in depth relative to the other by 5, 25, or 45 degrees. Each observer participated in 12 experimental conditions formed by the combination of 2 motion types (deforming vs. static boundary contours), 2 surface types (objects depicted as silhouettes or with texture and Lambertian shading), and 3 angular offsets (5, 25, and 45 degrees). When there was no motion (static silhouettes or stationary objects presented with shading and texture), the older observers performed as well as the younger observers. In the moving object conditions with shading and texture, the older observers' performance was facilitated by the motion, but the amount of this facilitation was reduced relative to that exhibited by the younger observers. In contrast, the older observers obtained no benefit in performance at all from the deforming (i.e., moving) silhouettes. The reduced ability of older observers to perceive 3D shape from motion is probably due to a low-level deterioration in the ability to detect and discriminate motion itself.