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861.
This study examined whether "melodic contour deafness" (insensitivity to the direction of pitch movement) in congenital amusia is associated with specific types of pitch patterns (discrete versus gliding pitches) or stimulus types (speech syllables versus complex tones). Thresholds for identification of pitch direction were obtained using discrete or gliding pitches in the syllable /ma/ or its complex tone analog, from nineteen amusics and nineteen controls, all healthy university students with Mandarin Chinese as their native language. Amusics, unlike controls, had more difficulty recognizing pitch direction in discrete than in gliding pitches, for both speech and non-speech stimuli. Also, amusic thresholds were not significantly affected by stimulus types (speech versus non-speech), whereas controls showed lower thresholds for tones than for speech. These findings help explain why amusics have greater difficulty with discrete musical pitch perception than with speech perception, in which continuously changing pitch movements are prevalent. 相似文献
862.
863.
Shi LZ Tang WH Liu XP 《Neuropsychology, development, and cognition. Section B, Aging, neuropsychology and cognition》2012,19(1-2):301-318
Source memory refers to mental processes of encoding and making attributions to the origin of information. We investigated schematic effects on source attributions of younger and older adults for different schema-based types of items, and their schema-utilization of judgments of learning (JOLs) in estimating source memory. Participants studied statements presented by two speakers either as a doctor or a lawyer: those in the schema-after-encoding condition were informed their occupation only before retrieving, while those of schema-before-encoding were presented the schematic information prior to study. Immediately after learning every item, they made judgments of the likelihood for it to be correctly attributed to the original source later. In the test, they fulfilled a task of source attributing. The results showed a two-edged effect of schemas: schema reliance improved source memory for schema-consistent items while impaired that for schema-inconsistent items, even with schematic information presented prior to encoding. Compared with younger adults, older adults benefited more from schema-based compensatory mechanisms. Both younger and older adults could make JOLs based on before-encoding schematic information, and the schema-based JOLs were more accurate in predicting source memory than JOLs made without schema support. However, even in the schema-after-encoding condition, older adults were able to make metacognitive judgments as accurately as younger adults did, though they did have great impairments in source memory itself. 相似文献
864.
865.
866.
Using the multiple-object tracking paradigm, this study examines how spontaneous appraisal for facial beauty affects distributed attention to multiple faces in dynamic displays. Observers tracked attractive faces more effectively than unattractive faces in this task. Tracking performance was only affected by target attractiveness, suggesting an absence of appraisal for distractor attractiveness. Attractive male faces also produced stronger binding of face identity and location for female participants. Together, the results suggest that facial attractiveness was appraised during tracking even though this was task irrelevant. Contrary to the theory that multiple-object tracking is driven by encapsulated low-level vision, our results show that the content of target representation is not only penetrable by social cognition but also modulates the course of tracking operations. 相似文献
867.
Probability is an important idea with a remarkably wide range of applications. However, psychological and instructional studies conducted in the last two decades have consistently documented poor understanding of probability among different populations across different settings. The purpose of this study is to develop a theoretical framework for describing teachers' understandings of probability. To this end, we conducted an 8-day seminar with eight high school statistics teachers in the summer of 2001. The data we collected include videotaped sessions and interviews, teachers' written work, and researchers' field notes. Our analysis of the data revealed that there was a complex mix of conceptions and understandings of probability, both within and across the teachers, which were situationally triggered, often incoherent when the teachers tried to reflect on them, and which did not support their attempts to develop coherent pedagogical strategies regarding probability and statistical inference. 相似文献
868.
The micromechanical model of extrusion formation in a single crystal under stress-controlled loading in high-cycle fatigue is reviewed. In the present letter, the microstress and strain fields of a single crystal under a high-amplitude fatigue are calculated by the boundary element method. Based on Schmidt's law, the resolved shear stress to activate or to cause the continuation of slip in a slip system is taken to depend on the amount of slip in that system. The cyclic strain hardening is calculated from the experimental tensile stress-strain curve. This calculated cyclic strain hardening is compared with the experimental cyclic hardening. Good agreement is shown. 相似文献
869.
The energetic driving force and resistance for shearing and cracking in metallic glasses (MGs) are quantitatively evaluated. A universal thermodynamic criterion is proposed for better understanding the intrinsic correlations between fracture toughness and Poisson’s ratio, the competitions between various deformation modes and the ductile-to-brittle transition in MGs and other materials. A new cooperation parameter δ is also introduced to depict quantitatively the relative propensity of shearing versus cracking. This work could provide insights into the long-standing issues of deformation mechanisms of glassy materials, and be helpful in searching for ductile and tough MGs. 相似文献
870.
Gong Li Y.P. Gao Z.H. Chi J. Liu T. Zhang R.P. Liu 《Philosophical Magazine Letters》2013,93(7):543-551
A 52 m drop tube has been used to solidify bulk-glass-forming Zr41Ti14Cu12.5Ni10Be22.5 alloy. Glassy balls with different sizes solidified from the droplets whose structural features, glass-transition behaviour and crystallization kinetics have been investigated. The results indicate that the apparent activation energies of the glass transition and main crystallization reaction are significantly different from those of samples prepared by water quenching. The structural difference between the two types of glassy specimen is revealed by compression studies and in situ energy-dispersive X-ray diffraction. The results are important for understanding the structural features of bulk-forming glasses. 相似文献