The role of activity in the development of long-range horizontal connections in area 17 of the ferret

Horizontal connections in area 17 of adult cats and ferrets link cells with similar preferred orientations by a patchy network of projections extending several millimeters across the cortex. The maturation of orientation selectivity in ferret area 17 has been demonstrated previously by quantitative single-unit recording and optical imaging to begin at approximately postnatal days (P) 32-P36. We therefore made restricted injections of cholera toxin B-subunit (CTB) or CTB-gold into ferret area 17 at a series of developmental ages and statistically quantified the degree of clustering in plots of retrogradely labeled cells in tangential sections through layer III for comparison to the published values for orientation tuning at each age. At P21, horizontal connections within area 17 lacked patchiness entirely, although clear patches of labeled cells were present in extrastriate areas. By P27, significant clustering of horizontal connections within area 17 was present. A second phase of cluster refinement was observed to occur at approximately P34-P36, coinciding with the emergence of mature orientation tuning and maps. Continuous silencing of cortical action potentials by chronic tetrodotoxin infusion from P21 resulted in a spatially random distribution of retrogradely labeled cells at P34. In contrast, bilateral enucleation from P21 did not prevent the initial development of clustered horizontal connections. We conclude, based on our findings and those of others, that the anatomical specificity of long-range horizontal connections results from an activity-dependent process that initially can use spontaneous activity in the cortical and thalamic networks to establish crude periodic connections and later uses visual cues to refine these connections.     

Converging measurement of horizontal and vertical individualism and collectivism.

The constructs of horizontal (H) and vertical (V) individualism (I) and collectivism (C) were theoretically defined and empirically supported. Study 1 confirmed, via factor analysis, that the 4 constructs, HI, V1, HC, and VC, which were previously found in the United States, which has an individualist culture, also were found in Korea which has a collectivist culture. Study 2 investigated multimethod-multitrait matrices measuring the constructs and generally supported their convergent and divergent validity. Study 3 showed how these 4 constructs relate to previously identified components by H. C. Triandis and colleagues. Study 4 showed the relationships of the measurement of the 4 constructs to some of the measures used by other researchers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

平立交替凿岩爆破技术在上向水平分层尾砂胶结充填采矿法的试验应用

针对鸡笼山金矿上向水平分层充填采矿法采场中存在的切割回采顺序及凿岩爆破参数不合理、出矿效率低、采场支护量大、回采作业安全性较差等问题,在采场回采中进行了平立交替凿岩爆破技术试验.详细介绍了平立交替凿岩爆破试验采场回采工艺及作业组织.试验取得了很好的技术经济指标,对类似条件矿山开采具有借鉴作用.     

Force treadmill for measuring vertical and horizontal ground reaction forces

We constructed a force treadmill to measure the vertical, horizontal and lateral components of the ground-reaction forces (Fz, Fy, Fx, respectively) and the ground-reaction force moments (Mz, My, Mx), respectively exerted by walking and running humans. The chassis of a custom-built, lightweight (90 kg), mechanically stiff treadmill was supported along its length by a large commercial force platform. The natural frequencies of vibration were >178 Hz for Fz and >87 Hz for Fy, i.e., well above the signal content of these ground-reaction forces. Mechanical tests and comparisons with data obtained from a force platform runway indicated that the force treadmill recorded Fz, Fy, Mx and My ground-reaction forces and moments accurately. Although the lowest natural frequency of vibration was 88 Hz for Fx, the signal-to-noise ratios for Fx and Mz were unacceptable. This device greatly decreases the time and laboratory space required for locomotion experiments and clinical evaluations. The modular design allows for independent use of both treadmill and force platform.     

Modulation of intrinsic circuits by serotonin 5-HT3 receptors in developing ferret visual cortex

Serotonergic projections are widespread in the developing neocortex, but their functions are obscure. The effects of 5-HT3 receptor agonists on cortical circuit response properties were studied in slices of ferret primary visual cortex using high-speed optical imaging of voltage-sensitive dye signals and whole-cell patch-clamp recording. Activation of the 5-HT3 receptor decreased the amplitude and lateral extent of excitation throughout postnatal development. This effect peaks after eye opening, which indicates a function for serotonergic modulation of circuit responses during the period of refinement of cortical connections. Whole-cell patch-clamp recordings from single neurons revealed that synaptic responses evoked by white matter stimulation were reduced by 5-HT3 receptor agonists, whereas the frequency of spontaneous GABAergic synaptic currents was enhanced dramatically. This indicates that the modulation of spontaneous synaptic activity by fast-acting serotonin receptors is reflected in an inhibition of the circuit response, in line with the notion of background synaptic activity altering the spatiotemporal integration properties of cortical cells by changing their membrane potential and their electrotonic structure. These mechanisms may regulate the response properties of intrinsic circuits in both the adult and developing neocortex.     

Stimulus dependence of orientation and direction sensitivity of cat LGNd relay cells without cortical inputs: a comparison with area 17 cells

The cortical contribution to the orientation and direction sensitivity of LGNd relay cells was investigated by recording the responses of relay cells to drifting sinusoidal gratings of varying spatial frequencies, moving bars, and moving spots in cats in which the visual cortex (areas 17, 18, 19, and LS) was ablated. For comparison, the spatial-frequency dependence of orientation and direction tuning of striate cortical cells was investigated employing the same quantitative techniques used to test LGNd cells. There are no significant differences in the orientation and direction tuning to relay cells in the LGNd of normal and decorticate cats. The orientation and direction sensitivities of cortical cells are dependent on stimulus parameters in a fashion qualitatively similar to that of LGNd cells. The differences in the spatial-frequency bandwidths of LGNd cells and cortical cells may explain many of their differences in orientation and direction tuning. Although factors beyond narrowness of spatial-frequency tuning must exist to account for the much stronger orientation and direction preferences of cells in area 17 when compared to LGNd cells, the evidence suggests that the orientation and direction biases present in the afferents to the visual cortex may contribute to the orientation and direction selectivities found in cortical cells.     

Relationship of cognitive style and theoretical orientation to psychology interns' preferences for supervision.

This study (N ?=?106) investigated the effects of cognitive style and theoretical orientation on psychology interns' judgments about the type of supervision they find most beneficial. Preferences for task-oriented and relationship-oriented supervision have been hypothesized to indicate lower and higher levels of professional development, respectively. This study, however, found that trainees' cognitive styles and the behavioral emphasis of their theoretical orientations were also significantly related to their preferences for these two types of supervisory environments. Individual-difference variables in addition to developmental level may need to figure more prominently in future models of psychotherapist training and supervision. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of horizontal vergence on the motor and sensory components of vertical fusion

PURPOSE: To compare motor and sensory capabilities for fusion of vertical disparities at different angles of horizontal vergence in healthy humans. METHODS: Eye movements were recorded from both eyes of 12 healthy subjects using three-axis search coils. The stimulus was a cross (+) (3.4 x 3.2 degrees , vertically and horizontally, respectively) presented to each eye with a stereoscopic display. Vertical disparities were introduced by adjusting the vertical position of the cross in front of one eye. The disparity was increased in small increments (0.08 degrees ) every 8 seconds. Viewing was defined as "near" if there was a horizontal disparity that elicited 6 degrees to 15 degrees convergence, depending on the subject's capability for horizontal fusion; viewing was defined as "far" at 1 degrees convergence. Maximum motor (measured), sensory (stimulus minus motor), and total (motor plus sensory) vertical fusion were compared. RESULTS: In 9 (75%) of 12 subjects the maximum total vertical fusion was more in near than in far viewing. The three who did not show this effect had relatively weak horizontal fusion. For the entire group, the motor component differed significantly between far (mean, 1.42 degrees ) and near (mean, 2.13 degrees). Total vertical fusion capability (motor plus sensory) also differed significantly between far (mean, 1.68 degrees ) and near (mean, 2.39 degrees ). For the sensory component there was no difference between between far (mean, 0.268 degrees ) and near (mean, 0.270 degrees ). As vertical disparity increased in a single trial, however, there was a small gradual increase of the contribution of the sensory component to vertical fusion. CONCLUSIONS: Vertical fusion capability usually increases with convergence. This increase is caused primarily by an increase in the motor component. There is a gradual but small increase in the sensory component as target disparity slowly increases.     

The speed and accuracy of reading horizontal, vertical, and circular scales.

"The speed and accuracy of reading comparable horizontal, vertical, and circular scales has been studied by means of a film… . The vertical scale is clearly less easy to read than either of the other two displays, particular difficulty being experienced near its ends. The success of the circular scale may be attributed to the fact that it presents a smaller area to be scanned. The shape of the visual field and the relative ease of moving the eyes from side to side, rather than up and down, are thought to account for the greater accuracy on the horizontal scale." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social comparison preferences among cancer patients as related to neuroticism and social comparison orientation

Effects of neuroticism and social comparison orientation on social comparison among cancer patients were examined. A computer program that enabled patients to access information about fellow patients' disease-related experiences was developed. Patients selected more interviews concerning more as compared to less fortunate others, spent more time reading, and showed more favorable reactions to such information. Individuals with a strong comparison orientation in particular tended to engage in and to respond to social comparison. Neuroticism was associated with higher interest in social comparison and with less favorable reactions, regardless of its direction. High-neurotic individuals reacted more positively to upward than to downward comparisons, whereas the reactions of low-neurotic individuals were unaffected by comparison direction. The latter effect was replicated using a general affect measure, but solely among individuals with a strong comparison orientation.     

Relationship of sex and professional training area to job orientation.

Examined indications that differences in job orientation may be more closely related to professional interests as reflected in one's professional training area than to differences in sex. 175 university students subgrouped into male business majors, female business majors, and female psychology majors rated the importance of 25 job characteristics comprising 3 job orientation dimensions--long-term career objectives, comfortable working environment and pleasant interpersonal relationships, and intrinsic job aspects. Male and female business majors differed significantly on the comfortable working environment and pleasant interpersonal relationships dimension, but business majors, regardless of sex, differed significantly from female psychology majors on all 3 dimensions, thus supporting the use of professional training area as a control variable in research related to sex differences in job orientation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Status and solidarity in social comparison: Agentic and communal values and vertical and horizontal directions.

Social comparison involves positioning the self relative to others on a vertical or status dimension (ranging from upward to downward comparisons) and a horizontal or solidarity dimension (ranging from contrastive to connective comparisons). Across 3 studies in which 389 undergraduates recorded everyday social comparisons (n = 4,417), downward and connective comparisons were rated as more helpful and mood enhancing than upward and contrastive comparisons. The effects of horizontal comparisons were greater for people for whom solidarity was an important value; however, the effects of vertical comparisons were not greater for people who valued status. The roles of the comparison target, topic, and situation were also explored; for example, noticing undesirable features of the target enhanced status but undermined solidarity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perception of spatial orientation in spasmodic torticollis. Part 2: The visual vertical

Heparan sulphates, the N-sulphated polysaccharides components of proteoglycans, are common constituents of cell surfaces and the extracellular matrix. The heparan sulphate polysaccharide chain has a unique molecular design in the which the clusters of N- and O-sulphated sugar residues, separated by regions of low sulphation, determine specific protein binding properties. The heparan sulphate chains are attached to various protein cores, which determine the location of the proteoglycan in the cell membrane and extracellular matrix. The diverse functions of heparan sulphate, which range from the control of blood coagulation to the regulation of cell growth and adhesion, depend on the capacity of the chains to activate protein ligands, such as antithrombin III and members of the fibroblast growth factor family. These properties are currently being exploited in the development of synthetic heparan sulphates as anticoagulants and promoters of wound healing. Conversely organic mimics of growth factor activating saccharides could possibly be designed to suppress tumour growth and prevent restenosis after coronary vessel angioplasty.     

The relationship of vertical and horizontal velocity gradients in the perception of shape, rotation, and rigidity

Perceived shape, rotation, and rigidity were investigated in displays with linear velocity gradients in the vertical and horizontal directions. Different temporal relationships between these gradients simulated perspective projections of frontally oriented or rotated translating dihedral angles, orthographic projections of rotating dihedral angles, or nonrigid motion. Displays with nonzero horizontal gradients were judged to represent greater angle magnitudes (less relative depth) than displays with 0 horizontal gradients. The temporal relationship between the vertical and horizontal gradients did not influence judged shape but did affect rotation and rigidity judgments; rigid rotations were judged to rotate most, and nonrigid displays were rated as least rigid. These results indicate that the visual system integrates information from more than 1 velocity field. Possible integration methods based on first-order optic flow analysis are discussed.     

Lesions of area 17 in newborn kittens cause selective changes in the development of area 18

In the cat, areas 17 and 18 interconnect soon after birth. To test the hypothesis that the normal development of area 18 depends on interactions with area 17, unilateral lesions of area 17 were created in newborn kittens, and the animals allowed to mature. Horseradish peroxidase was then injected into both lateral geniculate nuclei. The major abnormalities of area 18 in the lesioned hemispheres were a thinning of specifically layers 2 and 3 and abnormally faint geniculocortical labelling of layer 4. Cell densities in layers 2 and 3 of the lesioned hemispheres were similar to or lower than normal. Neonatal destruction of area 17 therefore produced a selective loss of cells in layers 2 and 3 in area 18 (the layers that normally interconnect with area 17), and may have reduced thalamic innervation of layer 4.     

Evidence for independent feedback control of horizontal and vertical saccades from Niemann-Pick type C disease

We measured the eye movements of three sisters with Niemann-Pick type C disease who had a selective defect of vertical saccades, which were slow and hypometric. Horizontal saccades, and horizontal and vertical pursuit and vestibular eye movements were similar to control subjects. The initial movement of oblique saccades was mainly horizontal and most of the vertical component occurred after the horizontal component ended; this resulted in strongly curved trajectories. After completion of the horizontal component of an oblique saccade, the eyes oscillated horizontally at 10-20 Hz until the vertical component ended. These findings are best explained by models that incorporate separate feedback loops for horizontal and vertical burst neurons, and in which the disease selectively affects vertical burst neurons.     

Development of orientation preference maps in area 18 of kitten visual cortex

We investigated the development of orientation preference maps in the visual cortex of kittens by repeated optical imaging from the same animal. Orientation maps became detectable for the first time around postnatal day (P) 17 and improved continuously in strength unitl P30, the time at which their appearance became adultlike. During this developmental period the overall geometry of the maps remained unchanged, suggesting that the layout of the orientation map is specified prior to P17. Hence, before the visual cortex becomes susceptible to experience-dependent modifications its functional architecture is largely specified. This suggests that the initial development and layout of orientation preference maps are determined by intrinsic processes that are independent of visual experience. This conclusion is further supported by the result that orientation maps were well expressed at P24 in binocularly deprived kittens. Because the appearance of the first orientation-selective neurons and the subsequent development of orientation preference maps correlated well with the time course of the expression and refinement of clustered horizontal connections, we propose that these connections might contribute to the specification of orientation preference maps.     

Dominance, prosocial orientation, and female preferences: Do nice guys really finish last?

Three multimethod studies (total N?=?348) probed the hypothesis that women's attraction to men would be influenced by male prosocial orientation. In Study 1, prosocial men were rated as more physically and sexually attractive, socially desirable, and desirable as dates than were nonprosocial men. Dominant men were no more attractive than low-dominance men, and male dominance did not interact with male prosocial orientation in eliciting attraction from women. In Study 2, prosocial orientation was manipulated to avoid "personalism," but still affected attraction. Across all measures attraction was an interactive function of dominance and prosocial tendencies. Dominance alone did not increase any form of attraction measured. In Study 3, male prosocial tendencies and dominance interacted to affect women's attraction to men. Results are discussed in terms of the place of altruism and dominance in evolutionary approaches to human interpersonal attraction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)