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771.
People rely on support from others to accomplish mundane and momentous tasks. When asking for assistance, is it beneficial to incentivize a helper by offering a motivated gift (i.e., a gift with the hope of getting support in return)? Six studies (N > 2,500) examine the frequency and potential costs of motivated gifts. In Study 1, a third of Americans indicated that they had given a motivated gift at least once, while nearly two‐thirds believed they had received one. In Studies 2a–d, most participants who imagined receiving a motivated gift before a favor request reported lower willingness to help and anticipated satisfaction from helping than participants who imagined simply being asked for a favor. Finally, Study 3 replicates these findings with actual help provided among friends in a laboratory setting. Findings suggest that motivated gifts are relatively common but may sometimes undermine the assistance that people hope to receive.  相似文献   
772.
The authors review previous examinations of the American Counseling Association's (ACA) Journal of Counseling & Development (JCD), consider various editors' policies that shaped the Journal, and update L. W. Harmon and H. E. Harker's (1989) analysis of special interest topics featured in JCD. Studying the flagship professional journal of ACA provides insight into the evolution and development of the profession of counseling.  相似文献   
773.
Recently it was shown that holeboard training can reinforce, i.e., transform early-LTP into late-LTP in the dentate gyrus during the initial formation of a long-term spatial reference memory in rats. The consolidation of LTP as well as of the reference memory was dependent on protein synthesis. We have now investigated the transmitter systems involved in this reinforcement and found that LTP-consolidation and memory retrieval were dependent on β-adrenergic, dopaminergic, and mineralocorticoid receptor (MR) activation, whereas glucocorticoid receptors (GRs) were not involved. Blockade of the β-adrenergic signaling pathway significantly increased the number of reference memory errors compared with MR and dopamine receptor inhibition. In addition, β-adrenergic blockade impaired the working memory. Therefore, we suggest that β-adrenergic receptor activation is the main signaling system required for the retrieval of spatial memory. In addition, other modulatory interactions such as dopaminergic as well as MR systems are involved. This result points to specific roles of different modulatory systems during the retrieval of specific components of spatial memory. The data provide evidence for similar integrative interactions between different signaling systems during cellular memory processes.  相似文献   
774.
TheSimon effect refers to the observation that subjects identify targets (e.g., colors) faster when the irrelevant spatial location of the target corresponds to the location of the response key. Theoretical accounts of the Simon effect typically explain performance in terms of automatic and controlled processes. Furthermore, the relative contributions of automatic and controlled processes are held to change as a function of the proportion of compatible to incompatible trials (compatibility proportion). Data are presented demonstrating that the reliability of the Simon effect, indexed by correlating its magnitude within subjects across blocks of trials, varied substantially as a function of the compatibility proportion. When the compatibility proportion was high, so was reliability. When the compatibility proportion was low, reliability was low as well. The results are discussed in terms of the relative reliability of automatic and controlled processes and the role of working memory and attentional control in goal maintenance.  相似文献   
775.
776.
Twelve- and 14-month-old infants' ability to represent another person's visual perspective (Level-1 visual perspective taking) was studied in a looking-time paradigm. Fourteen-month-olds looked longer at a person reaching for and grasping a new object when the old goal-object was visible than when it was invisible to the person (but visible to the infant). These findings are consistent with the interpretation that infants 'rationalized' the person's reach for a new object when the old goal-object was out of sight. Twelve-month-olds did not distinguish between test conditions. The present findings are consistent with recent research on infants' developing understanding of seeing.  相似文献   
777.
After prolonged viewing of a slowly drifting or rotating pattern under strict fixation, the pattern appears to slow down and then momentarily stop. The authors show that grouping can slow down the process of "motion fading," suggesting that cortical configural form analysis interacts with the computation of motion signals during motion fading. The authors determined that grouping slows motion fading because it can give rise to trackable features, such as virtual contour terminators not present in the image, that possess stronger motion signals than would occur in the absence of such trackable features. That a continuously rotating stimulus will eventually be perceived to stop, despite the presence of such trackable features, suggests that the motion-from-form system itself can be fatigued. The finding that stationary form can remain visible even after the motion signal has faded suggests that the neural bases of motion visibility and form visibility arise from different neuronal populations.  相似文献   
778.
This study was aimed at revealing which cognitive processes are lateralized in visual categorizations of "humans" by pigeons. To this end, pigeons were trained to categorize pictures of humans and then tested binocularly or monocularly (left or right eye) on the learned categorization and for transfer to novel exemplars (Experiment 1). Subsequent tests examined whether they relied on memorized features or on a conceptual strategy, using stimuli composed of new combinations of familiar and novel humans and backgrounds (Experiment 2), whether the hemispheres processed global or local information, using pictures with different levels of scrambling (Experiment 3), and whether they attended to configuration, using distorted human figures (Experiment 4). The results suggest that the left hemisphere employs a category strategy and concentrates on local features, while the right hemisphere uses an exemplar strategy and relies on configuration. These cognitive dichotomies of the cerebral hemispheres are largely shared by humans, suggesting that lateralized cognitive systems already defined the neural architecture of the common ancestor of birds and mammals.  相似文献   
779.
The Alternating Brightness Star (ABS) is an illusion that provides insight into the relationship between brightness perception and corner angle. Recent psychophysical studies of this illusion have shown that corner salience varies parametrically with corner angle, with sharp angles leading to strong illusory percepts and shallow angles leading to weak percepts. It is hypothesized that the illusory effects arise because of an interaction between surface corners and the shape of visual receptive fields: sharp surface corners may create hotspots of high local contrast due to processing by center-surround and other early receptive fields. If this hypothesis is correct, early visual neurons should respond powerfully to sharp corners and curved portions of surface edges. Indeed, the primary role of early visual neurons may be to localize the discontinuities along the edges of surfaces. If so, all early visual areas should show greater BOLD responses to sharp corners than to shallow corners. On the other hand, if corner processing is exclusively constrained to certain areas of the brain, only those specific areas will show greater responses to sharp vs shallow corners. To address this we explored the BOLD correlates of the ABS illusion in the human visual cortex using fMRI. We found that BOLD signal varies parametrically with corner angle throughout the visual cortex, offering the first neurophysiological correlates of the ABS illusion. This finding provides a neurophysiological basis for the previously reported psychophysical data that showed that corner salience varied parametrically with corner angle. We propose that all early visual areas localize discontinuities along the edges of surfaces, and that specific cortical corner-processing circuits further establish the specific nature of those discontinuities, such as their orientation.  相似文献   
780.
This study investigated the short-term stability of the 1991 Mirowsky-Ross 2 x 2 Index of the Sense of Control. From an ongoing longitudinal study, 304 subjects were randomly selected for test-retest interviews occurring 1 to 4 days after their regularly scheduled first follow-up interview. Test-retest reliability was assessed at the item level using percent agreement and weighted kappa. At the scale score level, reliability was assessed with the intraclass correlation coefficient (ICC). ICCs were also calculated within categories of demographic, socioeconomic, psychosocial, and functional status characteristics. There was moderate to substantial item-level agreement (mean weighted kappa = 51; weighted kappa range = .38 to .66). At the scale score level there was substantial agreement (ICC = .71). No appreciable differences in ICC values were found in the demographic, socioeconomic, psychosocial, and functional comparisons of status characteristics. Thus, this sense of control measure has acceptable test-retest reliability and is appropriate for use in longitudinal research.  相似文献   
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