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31.
汉字内隐记忆的实验研究(Ⅱ):任务分离和反应倾向 总被引:9,自引:0,他引:9
在实验I的基础上,操纵学习时的呈现时间(250ms,500ms,750ms)和注意变量(目标和非目标字),运用任务分离方法及间接证明逻辑,比较了再认测验和整字偏好测验在不同条件下的辨别力(A′)和反应倾向(B″)。结果:(1)双向功能分离的出现表明再认测验和偏好测验存在本质差异。根据“过程纯净”假设,可以推证内隐记忆存在于偏好测验中。此时,匹配比较法的标准未满足。(2)偏好测验中,500ms呈现目标字时,有显著正向启动效应:750ms呈现非目标字时,有显著负向启动效应。(3)内隐记忆和外显记忆发生时,都具有稳定的心理状态。但是前者的报告标准较松宽,而后者的较严格。 相似文献
32.
In the behavioral theory of timing, pacemaker rate is determined by overall rate of reinforcement. A two-alternative free-operant psychophysical procedure was employed to investigate whether pacemaker period was also sensitive to the differential rate of reinforcement. Responding on a left key during the first 25 s and on a right key during the second 25 s of a 50-s trial was reinforced at variable intervals, and variable-interval schedule values during the two halves of the trials were varied systematically. Responding on the right key during the first 25 s and on the left key during the second 25 s was not reinforced. Estimates of pacemaker period were derived from fits of a function predicted by the behavioral theory of timing to right-key response proportions in consecutive 5-s bins of the 50-s trial. Estimates of pacemaker period were shortest when the differential reinforcer rate most strongly favored right-key responses, and were longest when the differential reinforcer rate most strongly favored left-key responses. The results were consistent with the conclusion that pacemaker rate is influenced by relative reinforcer rate. 相似文献
33.
Genetic counseling for women of advanced maternal age who are considering prenatal testing continues to be based on a principle of nondirectiveness. We interviewed 11 genetic counseling students and four counselors about how they experience and manage, in practice, the tensions between the ideology of nondirectiveness and the acknowledged reality that one can never be truly nondirective. We found that our respondents creatively resolve this tension—simultaneously resisting and adhering to the values of nondirectiveness and information-giving—in individual and situation-specific ways. This resolution is facilitated by the extent to which information given to counselees is fluid, mobile and context-dependent, but these very features of information also have critical implications for both the norms and the practice of genetic counseling. 相似文献
34.
Human d-amphetamine drug discrimination: methamphetamine and hydromorphone. 总被引:2,自引:0,他引:2 下载免费PDF全文
Standard measures of subjective and discriminative effects of drugs were compared in 5 human volunteers. Subjects responded on a second-order color-tracking procedure, where 30 mg of d-amphetamine served as a discriminative stimulus for one response and its absence as the discriminative stimulus for another response. Self-reported subjective effects were assessed concurrently using the single-dose questionnaire, subscales of the Addiction Research Center Inventory, and several analogue rating scales. On different days following discrimination acquisition, varying doses of d-amphetamine, methamphetamine, and hydromorphone were administered. In these test sessions, either response was reinforced. Methamphetamine and d-amphetamine occasioned dose-related increases in d-amphetamine appropriate responding; hydromorphone did not. Methamphetamine and d-amphetamine occasioned dose-related increases in reports of the drug received being most like "speed"; hydromorphone occasioned dose-related increases in reports of the drug received being most like "dope." All three drugs occasioned dose-related increases in reports of drug liking, and increases in the morphine-benzedrine group, amphetamine, and benzedrine group scales of the Addiction Research Center Inventory. This experiment demonstrated that although explicit discriminative control of behavior by a drug may covary with drug identification, it does not necessarily covary with other self-reported subjective effects. Thus, the complementary nature of the data provided by drug discrimination and standard subjective-effects measures provides quantitative and qualitative data useful in studying both relatively novel compounds and the behavioral biology of psychoactive drugs in general. 相似文献
35.
Operant temporal discrimination learning was investigated in goldfish. In the first experiment, there was a fixed daily change in illumination. Eight subjects were trained to operate a lever that reinforced each press with food. The period during which responses were reinforced was then progressively reduced until it was 1 hr in every 24. The final 1-hr feeding schedule was maintained over 4 weeks. The feeding period commenced at the same time each day throughout. The food dispensers were then made inactive, and a period of extinction ensued for 6 days. The pattern of responding suggested that the fish were able to exhibit temporal discrimination in anticipation of feeding time. This pattern of responding persisted for a limited number of days during the extinction procedure. The second experiment produced evidence that operant temporal discrimination could develop under continuous illumination. 相似文献
36.
Discrimination of methadone and cocaine by pigeons without explicit discrimination training. 下载免费PDF全文
D W Schaal M P McDonald M A Miller M P Reilly 《Journal of the experimental analysis of behavior》1996,66(2):193-203
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training. 相似文献
37.
Detecting a nonevent: Delayed presence-versus-absence discrimination in pigeons 总被引:1,自引:1,他引:0 下载免费PDF全文
Eight pigeons were trained on a delayed presence-versus-absence discrimination paradigm in which a sample stimulus was presented on some trials but not on others. If a sample was presented, then a response to one choice key produced food. If no sample was presented, a response to the other choice key produced food. The basic finding was that performance remained constant and well above 50% correct on no-sample trials as the retention interval increased, whereas performance dropped precipitously (to below 50% correct) on sample trials. In the second phase of the experiment, all of the trials were no-sample trials, and reinforcers were delivered probabilistically for one group of pigeons and according to time-based schedules for the other group. The exact reinforcement probabilities used in Phase 2 were those calculated to be in effect on no-sample trials in Phase 1 (according to a discrete-state model of performance). Subjects did not show exclusive preference for the richer alternative on no-sample trials in the first phase, but those in the probabilistic group developed near-exclusive preference for the richer alternative during the second phase. These data are inconsistent with the predictions of the discrete-state model, but are easily accommodated by an account based on signal detection theory, which also can be applied effectively to discrimination of event duration and the “subjective shortening” effect. 相似文献
38.
A Bayesian approach for simultaneous optimization of test-based decisions is presented using the example of a selection decision
for a treatment followed by a mastery decision. A distinction is made between weak and strong rules where, as opposed to strong
rules, weak rules use prior test scores as collateral data. Conditions for monotonicity of optimal weak and strong rules are
presented. It is shown that under mild conditions on the test score distributions and utility functions, weak rules are always
compensatory by nature.
The authors are indebted to Wilbert Kallenberg for his valuable comments and to Jan Gulmans for providing the data for the
empirical example. The names of the authors are alphabetical; they are equally responsible for the contents of this paper. 相似文献
39.
Lynne Werner Olsho 《Infant behavior & development》1985,8(4):371-384
The results of an earlier study (Olsho, 1984) indicated that 5- to 8-month-old infants were relatively better at discriminating among high-frequency pitches than low. In the present study, sensory and nonsensory explanations for that effect were evaluated by examining infants' performance in a task requiring similar sensory processing but differing in the demands placed on processes such as memory. Infants' ability to resolve frequency was tested using a tonal masking paradigm, the psychophysical tuning curve. Twenty-four infants were tested at probe frequencies ranging from 500 to 4000 Hz; a group of young adults served as a comparison. Masked and unmasked thresholds were estimated using the visually reinforced head turn procedure in conjunction with an adaptive psychophysical method. Although infants' tuning curves fell below those of adults (indicating poorer performance), the widths and slopes of the infants' curves were not different from the adults'. Moreover, the difference between age groups remained constant across probe frequencies. These findings imply that by 5 months of age, the infant's ability to resolve sound frequency is similar to the adult's. 相似文献
40.
Blough DS 《Journal of the experimental analysis of behavior》1978,30(2):163-167
After extensive pretraining, three pigeons were exposed in 2-second trials to a random series of 14 light wavelengths, ranging in one nanometer (nm) steps from 575 nanometers to 589 nanometers. Responses to one of the wavelengths, 582 nanometers, were intermittently reinforced. The relative frequency of response approached 1.0 at 582 nanometers, and decreased with progressively higher and lower wavelengths. Reaction times shorter than about 0.2 second occurred with a low frequency that was largely independent of wavelength. Wavelength controlled the frequency of longer reaction times, but did not affect the distribution of these reaction times. Consequently, receiver-operating characteristic curves constructed by using reaction time as a rating measure did not conform to the signal-detection model, in contrast to such conformity when response rate is used in a similar way. The data suggest that stimulus onset as such triggers early response emission with some small probability; the probability of responses with longer latency is controlled by wavelength, but their time of emission is controlled by some independent process. 相似文献