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961.
An electronic speech timer that uses only relatively inexpensive and readily available electronic components and common circuitry is described. This device rapidly and accurately measures the durational characteristics of speech and the durations of other acoustic signals over extended lengths of time. Its application to the measurement of total speaking time, articulation time, and phonation time are outlined. Accuracy, reliability, and validity are discussed and compared with other, more time-consuming and cumbersome methods of durational measurement.  相似文献   
962.
One consistent finding in research using the memory search task developed by Sternberg (1966) is that negative set size has no effect on search reaction time, even when the negative set contains fewer items than the positive set. Such inefficient behavior appears to result from an intense positive focus generated by standard memory search task instructions. The present research was designed to explore the conditions under which a subject will switch focus to a smaller negative set. Two experiments were carried out using standard Sternberg instructions. The first experiment examined the effects of making the contents of the negative set explicit. The result was a shift to negative focus when the negative set was much smaller than the positive set. In the second experiment the size of the positive set was increased systematically to induce a shift to negative focus. The second experiment also examined the relationship between focus shift and measures of intelligence (Raven Progressive Matrices) and information storage capacity (digit span). The results are evidence that negative set size can affect reaction time in the memory search task, and that individual differences in ability to shift focus are related to intelligence.  相似文献   
963.
964.
Group learned helplessness is demonstrated in Experiment I. Groups of 2 tried to turn off noise by their joint action. In the solvable group (S), noise offset was contingent on their sequence of button pushing. In the yoked, unsolvable group (U), noise offset was independent of all sequences of button pushes they produced. In a practice group (O). subjects practiced coordinated sequences of button pushes with their partners, but heard no noise. Later, all 3 groups were tested in pairs in a shuttlebox which required coordinated joint responding to turn off noise. The unsolvable group escaped more poorly than the other 2 groups, paralleling helplessness effects with individuals. Experiment 2 and 3 found no transfer from individual helplessness training to group testing and no transfer from group helplessness training to individual testing. We suggest that the same mechanism, the expectation of response ineffectiveness, may mediate both individual and group learned helplessness.  相似文献   
965.
The effects of attentional-focus instructions (self vs partner focus) and level of partner arousal (high, low and ambiguous) on sexual responding, both objectively and subjectively measured, were examined with sexually-functional (N = 8) and sexually-dysfunctional (N = 8) men. These instructional sets were delivered just before the subjects viewed an erotic film depicting a heterosexual couple in which they identified with the male. When both groups were focusing on themselves rather than their partner, higher tumescence was observed when their partner was displaying low arousal. When the partner's level of arousal was ambiguous, highest tumescence was achieved during partner attentional focus. When the partner was displaying high sexual arousal, functional subjects reached highest levels of tumescence during partner focus, while dysfunctional subjects reached highest levels of tumescence during self focus. In fact, high partner arousal seemed to inhibit dysfunctional subjects' tumescence under partner focus. Examination of self-report of arousal data as measured by a subjective lever revealed interesting group differences. Results are discussed in light of possible maintaining factors in sexual dysfunction and their treatment implications.  相似文献   
966.
Subjects viewed 3 X 3 grids in which different subsets of the nine squares were designated as "figure," either by physical shading of those squares or by a verbal instruction to imagine those squares as shaded. The time taken by participants to respond "on" or "off" the figure was measured for single or multiple probe dots, which all appeared on or off the figural subset together, and which had already been shown to be equally detectable against shaded or unshaded squares and in all nine locations within the grid. In contrast to the set-size effect generally found in experiments on memory scanning, reaction time did not necessarily increase with the number of squares in the figural subset. Instead, the critical variable, which in previous research may often have adventitiously covaried with set size, was the spatial compactness of the subsets (as indexed by square-root-area over perimeter): Probes of less compact figures required more time to classify correctly. Subjects were evidently more successful in confining their attention to sets of mutually proximal items. Reasons are given for believing that this principle may also apply in the more abstract representational or semantic spaces that determine reaction times and errors in various other cognitive tasks.  相似文献   
967.
Happy, guilty, and neutral mood states were induced in participants who were then provided with an opportunity to donate blood for free, to donate in exchange for $5, or to choose between donating for free or for $5. As expected, there was a significantly higher incidence of helping when subjects felt happy and guilty as opposed to emotively neutral. Contrary to predictions, helping was unaffected by the type of incentive (donate for $5, donate for free, choose $5/free) subjects were offered in interaction with their mood state. However, the type of incentive did seem to influence the postdonation emotions of subjects: Guilty subjects who donated for money felt significantly less guilty following donation than prior to it and happy subjects felt more self-altruistic (kind and generous) following donation when they helped for free. The results are discussed in terms of Cialdini's negative state relief model (for negative moods) and the intrinsic qualities of helping (for positive moods).  相似文献   
968.
Hierarchical factor solution was used in the present paper in order to examine if two coding processes, simultaneous and successive, would load on a general 2nd level factor. It was further used to test if the coding processes and a factor representing planful behavior will not share the same general factor, revealing their relative independence as expected from a theoretical model of cognitive functions. Results supported the grouping of the coding tasks within a general factor, as well as the emergence of two general factors, one each for coding and planning. Further correlational evidence supported the relative independence of these two kinds of cognitive processes. These findings were discussed in the context of a general factor of intelligence.  相似文献   
969.
The hierarchical and radex models of ability organization are shown to be parallel. Both models suggest a complexity continuum along which cognitive performance tasks can be arrayed. In our revised radex model, the complexity continuum from the center to the periphery is shown to correspond to the general-to-specific dimension in factor analyses, or to test correlations with the general factor; complexity is redefined as apparent processing complexity. Examination of the theoretical and empirical bases for this continuum indicates its central importance for theories of intelligence.  相似文献   
970.
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