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791.
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793.
This study asked the question: What are the role expectancies of treatment personnel in the treatment community and are they consistent across patients' emotional condition? An 83-item inventory was developed and administered under three different sets of instructions, each characterizing a different patient condition. Treatment staff and administrators were asked to rate items on the basis of the level of expectancy they held for their team vocational rehabilitation counselor. The analyses suggest that treatment staff and counselors do not agree on role expectations and that patient condition is a significant mediating variable.  相似文献   
794.
SURVIVAL VALUE     
  相似文献   
795.
Three experiments are reported, which are attempts to replicate the finding of Ross and Gregory (1964) that difference thresholds for weights can be lowered by means of the size-weight illusion. Three different procedures were used, the first one (experiment I) being designed to show whether or not changes in a subject's judgement criterion could account for apparent changes in sensitivity. The second method (Experiment II) was a replication of Ross and Gregory's first procedure, in which the standard weight was judged before the comparison. In Experiments I and II a larger illusion was induced than in the original studies, but in Experiment III both the weights and container sizes were practically identical to those used by Ross and Gregory. The procedure was also the same as their most successful procedure (number 3) in which standard and comparison were judged simultaneously. The findings were uniformly negative: there was no evidence of criterion shift when the size-weight illusion was induced nor did we find the lowering of threshold previously reported.  相似文献   
796.
797.
Recent observations on the plasticity of brain and behavior relationships indicate that the temporary connections between environmental and neuroanatomical substrates have tremendous specificity but at the same time are very plastic. Establishment of a conditional reflex by stimulation of the hippocampal pyramidal layer and/or the mesencephalic reticular formation did not interfere with the differential stimulation of very near points in the same structures. These correlations between brain and behavior confirmed the earlier belief that the development of temporary connections between environment and brain is an elementary process of the central nervous system. Complex behavioral functions are organized through both neuronal and humoral afferentation. Data accumulated recently indicate that the descending forebrain influence is inhibitory in the brain stem and diencephalon and controls the sensory input in a somatomotor-specific and situation-specific manner. Humoral factors affecting thresholds can change the dynamic equilibrium existing between ascending excitatory and descending inhibitory systems; these alterations always follow the rule of situation and somatomotor specificity.  相似文献   
798.
Frequency DLs (Δf) at 1000 Hz were obtained in quiet and under masking conditions similar to those used in pitch-shift experiments, narrow-band noise at levels of 60, 80, and 100 dB SPL and tones at 15 dB SL or less. The Δfs were obtained by means of a tracking task in which the S controlled the input voltage to a frequency modulator. Characteristic improvement was seen when Δf was plotted as a function of sensation level. However, noise level itself was a significant factor, with more intense noise resulting in larger Δfs for tones of equal sensation level re masked threshold. This departure from previous findings is attributed to the signal and noise levels used, although the possibility exists that it is due to the use of modulated tones.  相似文献   
799.
The CFF was determined with three sectored disks, each of which corresponded to one of the three rings in a Helmholtz disk. The fusion frequency is identical for all three rings of a Helmholtz disk but with the three sectored disks it was found that the rate of stimulus occlusion is a major factor in determining the CFF. It was tentatively concluded that the effect was not a consequence of different stimulus wave-forms. The phenomenon appears to have been reported late in the last century.  相似文献   
800.
In our society an increasingly greater emphasis is being placed on group interaction and decision-making. Persons participating in such a process often use the term “group dynamics” to describe what is thought to be a social-psychological phenomenon. This article discusses some of the elements of “true” group characteristics and effects, and their possible existence in “group dynamic” situations. The article also deals with the implications of the effects of these elements in “group dynamic” environments on educational and administrative leadership and decision-making.  相似文献   
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