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161.
Gillian K. Straine 《Zygon》2020,55(2):344-346
The Science and Religion Forum (SRF) seeks to be the premier organization promoting the discussion between science and religion in the United Kingdom for academics, professionals, and interested lay people. Each year, the SRF holds a conference tackling a topical issue, and in 2019 focused on artificial intelligence and robotics. This article introduces the thematic section which is made up of three papers from that conference and provides a summary of the event.  相似文献   
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The acute effects of cocaine hydrochloride (4 to 96 mg/70 kg) and alcohol (0 to 1.0 g/kg), administered alone and in combination, were assessed in two experiments with human volunteers responding under a multiple schedule of repeated acquisition and performance of response chains. Subjects were intermittent users of cocaine and regular drinkers who were not cocaine or alcohol dependent. Alcohol was mixed with orange juice and ingested in six drinks within 30 min; cocaine was administered intranasally 45 min after completion of drinking. In each component of the multiple schedule, subjects completed response sequences using three keys of a numeric keypad. In the acquisition component, a new sequence was learned each session. In the performance component, the response sequence always remained the same. Results were consistent in both experiments, despite variations in the order in which the drugs were tested alone and in combination. Alcohol administered alone increased overall percentage of errors and decreased rates of responding in the acquisition component, whereas responding in the performance component generally was unaffected. Cocaine administered alone decreased rates of responding but did not affect accuracy of responding in the acquisition component, and enhanced accuracy of responding without affecting rates of responding in the performance component. The combined doses of cocaine and alcohol attenuated the effects observed with alcohol and cocaine alone. These results suggest that, under the conditions investigated in this study, (a) alcohol produces greater behavioral disruption than cocaine or cocaine-alcohol combinations, (b) cocaine and alcohol each attenuate effects of the other, and (c) such attenuation is most pronounced for cocaine attenuating the disruptive effects of alcohol.  相似文献   
165.
In three experiments, we investigated the relative perceived duration of a full bandwidth image and a set of high- and lowpass filtered images of a scene, briefly presented on a visual display unit. In Experiment 1, the various images were compared with each other, using a paired comparison method. All images were presented for 40 msec, and observers were asked to judge which of each pair of images had the longest duration. The results showed that images containing a wide spatial frequency bandwidth were judged to be of longer duration than were images of a narrower bandwidth, regardless of whether the latter were high- or lowpass filtered. In Experiment 2, a 40-msec presentation of each of the images was compared with a presentation of a probe that was 20, 40, 60, or 80 msec in duration. Observers again judged which of each pair of images had the longest duration. The results were very similar to those of Experiment 1, with wide bandwidth images being judged to be of longer duration than were narrow bandwidth images. In Experiment 3, instead of comparing the various filtered versions of the image with each other, we attempted to obtain a direct measure of perceived duration by comparing a flashing LED to a 40-msec flash of a subset of the images used in the previous experiments. The observers' task was to adjust the duration of the LED flash to match the perceived duration of each image.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
166.
In three experiments, we investigated the relative perceived duration of a full bandwidth iniage and a set of high- and lowpass filtered images of a scene, briefly presented on a visual display unit. In Experiment 1, the various images were compared with each other, using a paired comparison method. All images were presented for 40 msec, and observers were asked to judge which of each pair of images had the longest duration. The results showed that images containing a wide spatial frequency bandwidth were judged to be of longer duration than were images of a narrower bandwidth, regardless of whether the latter were high- or lowpass filtered. In Experiment 2, a 40-msec presentation of each of the images was compared with a presentation of a probe that was 20,40, 60, or 80 msec in duration. Observers again judged which of each pair of images had the longest duration. The results were very similar to those of Experiment 1, with wide bandwidth images being judged to be of longer duration than were narrow bandwidth images. In Experiment 3, instead of comparing the various filtered versions of the image with each other, we attempted to obtain a direct measure of perceived duration by comparing a flashing LED to a 40-msec flash of a subset of the images used in the previous experiments. The observers’ task was to adjust the duration of the LED flash to match the perceived duration of each image. The results confirmed the results of the previous experiments, again indicating that wide bandwidth images are perceived to have longer phenomenal durations than narrow bandwidth images are perceived to have. These results could be predicted from previous research in the literature on the effects of spatial frequency on perceptual lag but not from research on visual persistence. It is argued that the effects described here can probably be explained best by postulating a link between perceived duration and the integration of separately processed spatial frequency information.  相似文献   
167.
Two experiments designed to assess the functioning of the phonological store and loop were carried out with schizophrenic patients experiencing auditory hallucinations, schizophrenic patients not experiencing hallucinations and normal subjects. In the first experiment, phonological encoding was assessed. Although both groups of psychiatric patients performed more poorly overall than the normal subjects, there were no significant differences between the performances of the hallucinating and nonhallucinating patients. In the second experiment, the unattended speech effect (a phenomenon thought to reflect the functioning of the phonological store in normal subjects) was assessed in hallucinating schizophrenic patients, non-hallucinating schizophrenic patients and normal controls. The psychiatric patients performed more poorly overall than the normal subjects, but there was no evidence of abnormal functioning of the phonological store or loop in either patient group. Overall, the findings indicate that phonological store and loop abnormalities are not implicated in the experience of auditory hallucinations.  相似文献   
168.
AVERAGENESS, EXAGGERATION, AND FACIAL ATTRACTIVENESS   总被引:2,自引:0,他引:2  
Abstract— Langlois and her colleagues reported in this journal that composite faces are more attractive than the component faces used to create them, and conjectured that averageness is attractive (Langlois & Roggman, 1990, Langlois, Roggman, & Musselman, 1994) However, extremes may also be attractive (Perrett, May, & Yoshikawa, 1994). We investigated the effect of averageness (proximity to a norm or average face) on attractiveness using a computerized caricature generator to very averageness. Attractiveness increased with averageness (Experiment 1) and was negatively correlated with distinctiveness, a subjective measure of the converse of averageness (Experiments 1 and 2) Extremes (caricatures) were not attractive Line-drawing composites, which avoid some of the problems associated with gray-level composites, were significantly more attractive and less distinctive (more average) than individual faces (Experiment 2) These results support the claim that averageness is attractive.  相似文献   
169.
Developed and validated instruments for urban and culturally diverse adolescents to assess their self-reported transactions with family, peer, school, and neighborhood microsystems for the constructs of social support, daily hassles, and involvement. The sample of 998 youth were from schools in three Eastern cities with high percentages of economically disadvantaged youth. Data were collected before and after the transition to junior high school or to senior high school. Blacks constituted 26%, whites 26%, and Latinos 37% of the sample. Factor analyses confirmed and enhanced the hypothesized four-factor microsystem factor structure for support, hassles, and involvement; internal consistency and stability coefficients were consistent with these structures. In general, the microsystem factors were common across gender, ethnicity, and age. However, when group differences did occur on these demographic variables, they tended to validate the salience of microsystem specificity. In contrast to the total scores, the microsystem-specific factors yielded more meaningful and differential information with regard to demographic differences and the mediating processes across a school transition.  相似文献   
170.
Results on the Suinn-Lew Asian Self-Identity Acculturation Scale (SL-ASIA; Suinn, Rikard-Figueroa, Lew, & Vigil, 1987) confirm similarities between Singapore Asians and United States Asians on acculturation factors. The research also compared mean values on the SL-ASIA scale as a method of adding validity information regarding the scale. Singapore Asians did achieve a score indicative of Asian identity, whereas Asian Americans obtained a mean score indicative of higher Western acculturation.  相似文献   
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