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991.
In the experiment reported here the primary hypothesis proposed, which was supported by the data, was that subjects performing a two-choice self-paced serial RT task would learn to change their strategy of perceptual analysis of signals presented to them as they became progressively more practised. Early in practice each signal is identified as a particular state of the display and an appropriate response is then made. Well practised subjects, however, select their responses by reference to the change or constancy between successive displays. This strategy implies that the assumptions made by the generally accepted simple S-R connectionist model of two-choice serial RT may be quite misleading, since the choice of any particular response must be determined not only by the display state but also by what the previous response had been.  相似文献   
992.
The time constants of commercially available, electronic tachistoscopes are shown to be much poorer than is widely assumed. When a band near the centre of the visible spectrum is isolated, the output of a typical tachistoscope lamp takes approximately 18 ms to reach 90% of its asymptotic value; the time to decay to 10% is also typically 18 ms and we demonstrate conditions under which the decaying trace remains visually effective against a dark field for more than 40 ms after the nominal offset of the lamps.

Many reports of tachistoscopic experiments published in the last two decades must be quantitatively in error; and we provide examples of experiments where qualitative conclusions may have been drawn invalidly.  相似文献   
993.
A neurophysiologic model for aggessive behavior in the cat is proposed. Stimulus-bound and seizure-bound aggression was evaluated in relation to limbic and basal ganglia induced seizures (after-discharges). Electrically induced limbic and basal ganglia afterdischarges were used because they are known to implicate septohypothalamic sites from which aggression can be elicited by direct stimulation. The occurrence of behavioral aggression is correlated with the discharge characteristics of a single discharging system and with two interacting discharging systems. Aggression is composed of autonomic and somato-motor components which poses relatively low and high thresholds, respectively, for their activation. Aggression occurring during a combined septum and amygdala discharge was more intense and prolonged than with a septum discharge alone. Participation of a slow frequency discharging basal ganglia system activated seizurebound aggression in an otherwise nonaggressive limbic seizure. The limbic and basal ganglia stimulations and after-discharges lowered the excitability threshold of the aggression system and made it more vulnerable to being activated by external stimuli, such as visual and auditory stimuli. These observations are reminiscent of patients with aggressive behavior associated with psychomotor seizures.  相似文献   
994.
An automated multipurpose activity platform (MAP) that can be used to measure activity in the horizontal plane is described. Detection of the position of a small-bodied animal is based on completion of an electronic circuit in one or several cells of a 21 by 21 matrix below the floor. The MAP is constructed on the basis of an 11 by 11 matrix, but, through electronic averaging, operates functionally on the basis of a 21 by 21 matrix. The MAP has no built-in data storage facility and needs to be interfaced with a recording system. The system has been successfully utilized in measuring open-field activity of the rats.  相似文献   
995.
About 1000 WIN welfare clients were selected in five cities: Harlem, New Brunswick, Milwaukee, Wichita, and Tacoma, and half were randomly assigned to the Job Club program. Of the continuing clients, 87% of the Job Club sample obtained jobs vs 59% of the Control sample at the 12-month follow-up and 80 vs 48% at 6 months. The Job Club was more effective in each of the five cities, for men and women, for high school graduates or dropouts, for blacks, whites, and Spanish, for handicapped or nonhandicapped, veterans or nonveterans, the young and the older, and for those required to participate as well as those who volunteered. The jobs obtained by the Job Club clients were comparable to the Control clients' jobs in terms of mean salary, full-time status, and type of job, and were more likely to be enduring, nonsubsidized, and obtained by the job-seeker's own efforts. Job Club members obtained employment in a median of six sessions (mean of 11); 90% obtained jobs within 23 sessions. Follow-up questionnaire data indicated comparable job retention in the two samples but slightly greater advancement and job satisfaction for the Job Club clients. The method appears to assure employment to virtually all participating welfare clients.  相似文献   
996.
Data from 4035 participants in Project TALENT were analyzed to examine the extent to which known sex differences in achievement held up when early potential for achievement was contolled. Original TALENT data, consisting of information on socioeconomic background, cognitive abilities, and educational and occupational aspirations, were collected in 1960 when members of the study sample were in Grade 9. Follow-up surveys measuring participants' educational and occupational attainment were conducted at 1, 5, and 11 years after the date of participants' expected graduation from high school. Women had higher high school grades and scored higher on a composite of academic ability tests taken in Grade 9 than did men. However, by 11 years after high school, men had acquired more education and were earning more money on the job. Sex differences in realization of achievement potential were found across all socioeconomic levels. At least part of the reason behind women's relative failure to translate potential into achievement may lie in the greater conflict, for women, between the roles of spouse/parent and the roles of student/worker: variables measuring the onset, duration, and extent of family-related commitments were more strongly related to female than to male realization of potential. Sex differences in achievement grew larger between the 5- and 11-year follow-ups as a greater proportion of women in the study sample became wives and mothers. The widening of the sex gap in achievement during this period was particularly pronounced among the subgroup of individuals who were in the top quartile of potential in Grade 9.  相似文献   
997.
Stages of career development consistent with age were found in a group of employed managers and professionals. They tended to attribute career success to inherent abilities, education, and developmental experiences in the company studied. Trends among three age groups were similar in regard to factors they perceived as enhancing or adversely affecting their career development.  相似文献   
998.
999.
A cross-cultural examination of the attributions for the life satisfactions of the elderly was conducted by using a sample of 80 Asian-Indian and 80 United States retired citizens. It was hypothesized that factors of hard work, luck, family ties, religious faith, travel and recreation, personal abilities, money, social status, service to others and friendships would account for differences in the attributions for life-satisfactions of the two cultural groups. Results showed that more Asian than United States subjects reported satisfaction with life. Consistent with predictions, the attributions of the Asian group showed religious faith, service to others, family ties and luck as being very important factors contributing to life satisfaction. By contrast, more United States subjects reported that hard work, personal abilities, travel and recreation, and social status had significantly influenced their life satisfactions. Findings were interpreted in terms of cultural and socio-psychological variables which influence the attributions for life satisfactions.  相似文献   
1000.
Results of 1,579 observations of cars entering or exiting campus parking lots showed direct relationships between seat belt wearing and the intrusiveness of the engineering device designed to induce belt usage, and between device intrusiveness and system defeat. For example, all drivers with working interlocks or unlimited buzzer reminders were wearing a seat belt; but 62% of the systems with interlocks or unlimited buzzers had been defeated, and only 15.9% of the drivers in these cars were wearing a seat belt. The normative data indicated marked ineffectiveness of the negative reinforcement contingencies implied by current seat belt inducement systems; but suggested that unlimited buzzer systems would be the optimal system currently available if contingencies were developed to discourage the disconnection and circumvention of such systems. Positive reinforcement strategies are discussed that would be quite feasible for large-scale promotion of seat belt usage.  相似文献   
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