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111.
Robert E. Remez Emily F. Thomas Kathryn R. Dubowski Stavroula M. Koinis Natalie A. C. Porter Nina U. Paddu Marina Moskalenko Yael S. Grossman 《Attention, perception & psychophysics》2013,75(7):1353-1358
In a spoken utterance, a talker expresses linguistic constituents in serial order. A listener resolves these linguistic properties in the rapidly fading auditory sample. Classic measures agree that auditory integration occurs at a fine temporal grain. In contrast, recent studies have proposed that sensory integration of speech occurs at a coarser grain, approximate to the syllable, on the basis of indirect and relatively insensitive perceptual measures. Evidence from cognitive neuroscience and behavioral primatology has also been adduced to support the claim of sensory integration at the pace of syllables. In the present investigation, we used direct performance measures of integration, applying an acoustic technique to isolate the contribution of short-term acoustic properties to the assay of modulation sensitivity. In corroborating the classic finding of a fine temporal grain of integration, these functional measures can inform theory and speculation in accounts of speech perception. 相似文献
112.
Stephen J. Ceci Paul B. Papierno Katrin U. Mueller-Johnson 《Journal of School Psychology》2002,40(6):477-484
In this commentary we explore both putative and potential relationships between school funding and educational outcomes, for which numerous indices and variables have been examined during the past two decades. We conclude that despite large increases in real dollars, there is no readily discernable link between inputs and outputs, although when statistical control is exerted over prior ability, school mix, and teacher turn-over, certain causal inferences appear warranted. However, it can be argued that the dominant analogy should be reconsidered, and schools serving large numbers of needy children may require higher inputs to keep from further declines, much like certain departments of a hospital require disproportionately more resources than others in order to be successful because they deal with problems that are more severe. 相似文献
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This article explores a variety of personal and professional boundary issues encountered by seminary faculty. The authors contend that boundary crossing is inevitable in contemporary theological education, which is structured such that professors engage in multiple roles with students as they attend to the education of the whole person. Guidelines are reviewed for minimizing risk to students and professors. Topics include life as a community member, student‐faculty friendship, and romantic relationships. Attention to work/life balance is seen as critical to the prevention of misconduct. The article ends with a call for continued conversation as well as institutional accountability and change. 相似文献
115.
A. H. Clarke J. Ditterich K. Drüen U. Schönfeld C. Steineke 《Behavior research methods》2002,34(4):549-560
A novel three-dimensional eye tracker is described and its performance evaluated. In contrast to previous devices based on conventional video standards, the present eye tracker is based on programmable CMOS image sensors, interfaced directly to digital processing circuitry to permit real-time image acquisition and processing. This architecture provides a number of important advantages, including image sampling rates of up to 400/sec measurement, direct pixel addressing for preprocessing and acquisition, and hard-disk storage of relevant image data. The reconfigurable digital processing circuitry also facilitatesin-line optimization of the front-end, time-critical processes. The primary acquisition algorithm for tracking the pupil and other eye features is designed around the generalized Hough transform. The tracker permits comprehensive measurement of eye movement (three degrees of freedom) and head movement (six degrees of freedom), and thus provides the basis for many types of vestibulo-oculomotor and visual research. The device has been qualified by the German Space Agency (DLR) and NASA for deployment on the International Space Station. It is foreseen that the device will be used together with appropriate stimulus generators as a general purpose facility for visual and vestibular experiments. Initial verification studies with an artificial eye demonstrate a measurement resolution of better than 0.1° in all three components (i.e., system noise for each of the components measured as 0.006° H, 0.005° V, and 0.016° T. Over a range of ±20° eye rotation, linearity was found to be <0.5% (H), <0.5% (V), and <2.0% (T). A comparison with the scierai search coil technique yieldednear equivalent values for the systemnoise and the thickness of Listing’s plane. 相似文献
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In three experiments, we investigated how associative word-word priming effects in German depend on different types of syntactic context in which the related words are embedded. The associative relation always concerned a verb as prime and a noun as target. Prime word and target word were embedded in visually presented strings of words that formed either a correct sentence, a scrambled list of words, or a sentence in which the target noun and the preceding definite article disagreed in syntactic gender. In contrast to previous studies (O’Seaghdha, 1989; Simpson, Peterson, Casteel, & Burgess, 1989), associative priming effects were not only obtained in correct sentences but also in scrambled word lists. Associative priming, however, was not obtained when the definite article and the target noun disagreed in syntactic gender. The latter finding suggests that a rather local violation of syntactic coherence reduces or eliminates word-word priming effects. The results are discussed in the context of related work on the effect of gender dis-/agreement between a syntactic context and a target noun. 相似文献
120.
Abrams TW Yovell Y Onyike CU Cohen JE Jarrard HE 《Learning & memory (Cold Spring Harbor, N.Y.)》1998,4(6):496-509
An important recent insight in a number of neurobiological systems is that during learning, individual dually regulated proteins with associative properties function as critical sites of stimulus convergence. During conditioning in Aplysia, the Ca2+ /calmodulin-sensitive adenylyl cyclase (AC) in mechanosensory neurons serves as a molecular site of interaction between Ca2+ and serotonin [5-hydroxytryptamine (5-HT)]-two signals that represent the CS and US in these cells. Conditioning requires that the CS and US be paired within a narrow time window and in the appropriate sequence. AC shows an analogous sequence preference: It is more effectively activated when a pulse of Ca2+ precedes a pulse of 5-HT than when the 5-HT precedes Ca2+. One mechanism that contributes to this sequence preference is that Ca2+/calmodulin binding to AC accelerates the rate of AC activation by receptor-Gs. We have identified two additional properties of AC activation that would cause pairing with Ca2+ preceding 5-HT to be more effective than simultaneous pairing or pairing with the reciprocal sequence: (1) Activation of Aplysia AC by a Ca2+ pulse rose with a delay compared with activation by a 5-HT pulse. (2) A late pulse of Ca2+, which arrived after 5-HT, acted, via calmodulin, to accelerate the decay of AC activation by receptor-Gs. Together, these activation properties of AC may contribute to the CS-US sequence requirement of classical conditioning. 相似文献