Transfer of matching-to-figure samples in the pigeon

Three pigeons were trained on a modified six-key matching-to-sample procedure. The third peck on the figure-sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two-component chains or discrete five-key discriminations.     

The case for praxics

Since the early 1900s a variety of names has been proposed for the scientific study of behavior, but none has come into general use. "Praxics," a recent entry, is defensible on several grounds. "Behaviorism," on the other hand, is the name of a school of philosophy. Though praxics has roots in behaviorism, the term "behaviorism" should not be applied to praxics. Confusion between the science and the philosophy has retarded the growth of the science immeasurably. Its growth has also been impeded by its association with psychology, which is still primarily the study of mind. Efforts are underway to establish praxics as an independent field.     

Effects of concurrent schedules on human fixed-interval performance

Young adults performed a lever-pressing task for money on two schedules of reinforcement: concurrent fixed-interval 1 min—differential-reinforcement-of-low-rate 20-sec, and concurrent fixed-interval 1-min—fixed ratio 100 responses. All subjects were trained on both schedules. Fixed-interval performance concurrent with the differential reinforcement procedure was characterized by high constant rates with no post-reinforcement pauses. Fixed-interval performance concurrent with fixed ratio was characterized by low rates and lengthy post-reinforcement pauses. These results differ from those obtained in prior studies on the effects of conditioning history upon subsequent fixed-interval performance. The prior work, using non-concurrent procedures, had shown that fixed-interval performance following differential reinforcement of low rates was characterized by post-reinforcement pauses and low rates, while fixed-interval performance following fixed ratio exhibited high constant rates and no post-reinforcement pause. The present results suggest that alternative concurrent contingencies are another major determinant of human fixed-interval performance.     

The development of stimulus control with and without a lighted key

In two experiments, the effect of an illuminated response key on the acquisition of stimulus control by an airflow stimulus was assessed. In the first experiment, pigeons were given nondifferential training with airflow emerging from behind the response key in one of three conditions of illumination: trained to peck a lighted key, trained to peck an unlighted key with a houselight present, trained to peck a key in total darkness. After 10 days of training on a variable-interval schedule of reinforcement, all subjects were given a generalization test on airflow velocity. The gradients for subjects trained in the dark were sharp, while those for subjects trained in lighted conditions were shallow. In the second experiment, the effect of an irrelevant keylight on the acquisition of an airflow velocity discrimination was assessed. Two groups of pigeons were trained to discriminate two airflow velocities. One group was trained with a lighted response key and the other was trained to peck the response key in total darkness. The dark-trained subjects acquired the discrimination more rapidly. The results demonstrate that the acquisition of stimulus control by airflow with either a differential or nondifferential training procedure can be overshadowed by keylight.     

A conditioning technique applicable to elementary school classrooms

A procedure was developed for use in a public school classroom where only one of the children needed treatment, sophisticated apparatus was not feasible, personnel were untrained in conditioning techniques, and where disruption had to be minimized. Candy reinforcers were contingent upon working behavior. The total candy earned in the session was divided equally among the class. Portable radio control apparatus was adopted to give feedback to the child when he was displaying the desired working behavior. An increase in working behavior and a decrease in talking aloud and out-of-seat behavior was observed for each of the four subjects. When the feedback apparatus was removed, the desired behavior was maintained through candy reinforcement alone in all four subjects.     

Stimulus control in the goldfish after massed extinction

Compared with the data of goldfish trained only with stimuli correlated with reinforcement, interspersed reinforcement-stimulus and extinction-stimulus trials resulted in sharper stimulus control and a marked reduction in the percentage of key-presses emitted in the presence of stimuli located near the extinction stimulus on the test dimension. If non-reinforced trials were not interspersed with reinforced trials, there was no sharpening of stimulus control and less reduction in key presses in the presence of stimuli near the extinction stimulus on the test dimension.     

西方关于青年马克思与异化的辯論

马克思早期著作的出版提供给我们一幅关于社会主义思想早期发展的图景,使人更清楚地看到它同哲学和社会学中现行讨论之间的联系。这一联系即早期马克思对此曾多所涉及的异化现象。在这篇论文里,作者指出对异化现象的现时流行的两种主要探索方法——本体论的和社会学的方法——的特征并提出这种看法:早期马克思对这一现象的分析中的黑格尔的本体论和经验社会学之间的紧张关系反映出这一分析——对理解人的地位的一种贡献——的优点而非弱点。