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The ability to make egocentric distance estimates of a single point source of light, seen in darkness and without the cues of changing size and luminance, was investigated in sixteen observers. The attenuation required to maintain constant luminance, when the target was viewed from different distances, was shown to follow the inverse square law providing the angle subtended by the light was less than 20 s arc. Distance changes were also simulated by means of a split mirror which produced vergence cues, or by test lenses to provide accommodation cues. Over the range 0.5 to 9.2 m distance estimates were surprisingly accurate, although there was some overestimation of near and underestimation of far distances. Most observers made good judgements when only convergence cues were varied, whereas no observers made consistently good judgements when only accommodation cues were varied. The difficulties are discussed in terms of the accommodation-convergence link. When distance was simulated by changing convergence and accommodation cues, estimates were not as good as when real distance was changed. Since good estimates were made with brief target exposures, these judgements were not based on subsequent convergence or accommodation changes. It is suggested that the metric or reference against which the apparently absolute judgements were made was the efferent demand signal associated with a 'resting' position of convergence in darkness.  相似文献   
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Four experiments were conducted to determine whether echoic memory plays a role in differences between good and poor readers. The first two experiments used a suffix procedure in which the subject is read a list of digits with either a tone control or the word go appended to the list. For lists that exceeded the length of the subjects memory span by one digit (i.e., that avoided ceiling effects), the poor readers showed a larger decrement in the suffix condition than did the good readers. The third experiment was directed at the question of whether the duration of echoic memory is different for good and poor readers. Children shadowed words presented to one ear at a rate determined to give 75-85% shadowing accuracy. The items presented to the nonattended ear were words and an occasional digit. At various intervals after the presentation of the digit, a light signaled that the subject was to cease shadowing and attempt to recall any digit that had occurred in the nonattended ear recently. Whereas good and poor readers recalled the digit equally if tested immediately after presentation, the poor readers showed a faster decline in recall of the digit as retention interval increased. A fourth experiment was conducted to determine whether the differences in echoic memory were specific to speech stimuli or occurred at a more basic level of aural persistence. Bursts of white noise were separated by 9-400 ms of silence and the subject was to say whether there were one or two sounds presented. There were no differences in detectability functions for good and poor readers.  相似文献   
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The current study hypothesized that (1) hope would negatively predict burdensomeness, thwarted belongingness, and acquired capability to enact lethal injury; (2) hope would negatively predict suicidal ideation; and (3) the interpersonal suicide risk factors would predict suicidal ideation. Results indicated that hope negatively predicted burdensomeness and thwarted belongingness, but positively predicted acquired capability to enact suicide. Contrary to our second hypothesis, hope did not predict suicidal ideation, but interpersonal risk factors for suicide predicted suicidal ideation. Results are discussed in terms of implications for hope theory and Joiner's (2005) interpersonal risk factors for suicide, and for clinical practice.  相似文献   
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This study explored the association between interpersonal factors and depressive symptoms in first-time mothers over the first two years of parenthood. An interpersonal style characterized by dependency, recollections of rejection in childhood, and current relationship characteristics was assessed in a nonclinical sample of 133 women. The final model explained 52% of the variance in depressive symptoms at 24 months. Controlling for initial symptom levels, interpersonal variables explained 24% of the outcome variance. The findings suggest that two interpersonal attributes, peer rejection in childhood and a dependent interpersonal style, are particularly important to our understanding of depressive symptomatology.  相似文献   
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Self‐abandonment and self‐denial are, respectively, Catholic and hyper‐Calvinist analogues of each other. Roughly, each requires the surrendering of a person to God's will and providence through faith, hope, and love. Should the self‐abandoning/self‐denying individual accept his or her own damnation if that be God's will? This article, which is virtually alone in discussing the Catholic and Reformed Protestant traditions together, answers “No.” The unqualified self‐abandonment present in quietism and the radical self‐denial of Samuel Hopkins are perverse and irrational responses to the prospect of hell because they run counter to the Christian's deepest need to spend eternity with God. However, a qualified self‐abandonment is intellectually defensible and offers a viable Christian piety.  相似文献   
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