The nature of control by spoken words over visual stimulus selection.

Eight retarded adolescents were trained to select one (a trained S+) of two visual stimuli in response to a spoken word (a trained word). Two different visual stimuli alternated randomly as the S-. To determine if the spoken work was merely a temporal discriminative stimulus for when to respond, or if it also specified which visual stimulus to select, the subjects were given intermittent presentations of untrained (novel) spoken words. All subjects consistently selected the trained S+ in response to the trained spoken word and selected the previous S- in response to the untrained spoken words. It was hypothesized that the subjects were responding away from the trained S+ in response to untrained spoken words, and control by untrained spoken words would not be observed when the trained S+ was not present. The two visual S- stimuli selected on trials of untrained spoken words were presented simultaneously. The untrained spoken words presented on these trials no longer controlled stimulus selections for seven subjects. The results supported the hypothesis that previous control by spoken words was due to responding away from the trained S+ in response to untrained spoken words.     

Delayed and current stimulus control in successive discriminations

In a successive discrimination in which successively alternating red and green hues signaled component variable-interval schedules, sensitivity of the ratio of responses in the two components to variation in the component reinforcer ratio decreased systematically during the course of the component. This decrease in stimulus control or discrimination over the course of the component was shown to be the result of delayed control of responding during the component by the stimulus transition between components. When the red–green stimulus transition was altered by interpolating a white stimulus at the end of each 60-s component, discrimination at the beginning of the component (measured by the power-function exponent for sensitivity to reinforcement) was reduced. Conditions with the white stimulus inserted in other quarters of the component indicated that the current discriminative stimulus exerts control over responding throughout the component, whereas during about the first half of the component, response differentials are influenced by the transition between discriminative stimuli.     

Simultaneous auditory discrimination.

Stimuli in many visual stimulus control studies typically are presented simultaneously; in contrast the stimuli in auditory discrimination studies are presented successively. Many everyday auditory stimuli that control responding occur simultaneously. This suggests that simultaneous auditory discriminations should be readily acquired. The purpose of the present experiment was to train rats in a simultaneous auditory discrimination. The apparatus consisted of a cage with two response levers mounted on one wall and a speaker mounted adjacent to each lever. A feeder was mounted on the opposite wall. In a go-right/go-left procedure, two stimuli were presented on each trial, a wide-band noise burst through one speaker and a 2-kHz complex signal through the other. The stimuli alternated randomly from side to side across trials, and the stimulus correlated with reinforcement for presses varied across subjects. The rats acquired the discrimination in 400 to 700 trials, and no response position preference developed during acquisition. The ease with which the simultaneous discrimination was acquired suggests that procedures, such as matching to sample, that require simultaneous presentation of stimuli can be used with auditory stimuli in animals having poor vision.     

Support for a theory of memory for event duration must distinguish between test-trial ambiguity and actual memory loss

Staddon and Higa's (1999) trace-strength theory of timing and memory for event duration can account for pigeons' bias to "choose short" when retention intervals are introduced and to "choose long" when, following training with a fixed retention interval, retention intervals are shortened. However, it does not account for the failure of pigeons to choose short when the intertrial interval is distinct from the retention interval. That finding suggests that stimulus generalization (or ambiguity) between the intertrial interval and the retention interval may result in an effect that has been attributed to memory loss. Such artifacts must be eliminated before a theory of memory for event duration can be adequately tested.     

中国背景下员工建言行为结构及中庸思维对其的影响

企业的自主创新离不开员工的自发性和创造性, 员工建言行为研究因此愈加受到重视。本研究拟探索中国背景下企业员工建言行为的结构(研究一), 并检验中国人的典型思维特征－中庸思维与中国背景建言行为的关系(研究二)。研究一通过对长三角地区30名企业员工的访谈提取建言行为关键事件, 编制初始问卷, 再通过对159名被试的探索性因素分析, 抽取出顾全大局式和自我冒进式两个建言行为维度; 另一批159名被试的验证性因素分析结果进一步证实了该结构。研究二以278份配对员工为样本, 层次回归分析结果表明, 中庸思维与顾全大局式建言存在正相关, 与自我冒进式建言存在负相关, 且授权对中庸思维与两类建言行为之间关系存在着调节作用。     

On the development and mechanics of delayed matching-to-sample performance

Despite its frequent use to assess effects of environmental and pharmacological variables on short-term memory, little is known about the development of delayed matching-to-sample (DMTS) performance. This study was designed to examine the dimensions and dynamics of DMTS performance development over a long period of exposure to provide a more secure foundation for assessing stability in future research. Six pigeons were exposed to a DMTS task with variable delays for 300 sessions (i.e., 18,000 total trials; 3,600 trials per retention interval). Percent-correct and log-d measures used to quantify the development of conditional stimulus control under the procedure generally and at each of five retention intervals (0, 2, 4, 8 and 16-s) individually revealed that high levels of accuracy developed relatively quickly under the shorter retention intervals, but increases in accuracy under the longer retention intervals sometimes were not observed until 100-150 sessions had passed, with some still increasing at Session 300. Analyses of errors suggested that retention intervals induced biases by shifting control from the sample stimulus to control by position, something that was predicted by observed response biases during initial training. These results suggest that although it may require a great deal of exposure to DMTS prior to obtaining asymptotic steady state, quantification of model parameters may help predict trends when extended exposure is not feasible.     

Matching: its acquisition and generalization

Choice typically is studied by exposing organisms to concurrent variable-interval schedules in which not only responses controlled by stimuli on the key are acquired but also switching responses and likely other operants as well. In the present research, discriminated key-pecking responses in pigeons were first acquired using a multiple schedule that minimized the reinforcement of switching operants. Then, choice was assessed during concurrent-probe periods in which pairs of discriminative stimuli were presented concurrently. Upon initial exposure to concurrently presented stimuli, choice approximated exclusive preference for the alternative associated with the higher reinforcement frequency. Concurrent schedules were then implemented that gave increasingly greater opportunities for switching operants to be conditioned. As these operants were acquired, the relation of relative response frequency to relative reinforcement frequency converged toward a matching relation. An account of matching with concurrent schedules is proposed in which responding exclusively to the discriminative stimulus associated with the higher reinforcement frequency declines as the concurrent stimuli become more similar and other operants-notably switching-are acquired and generalize to stimuli from both alternatives. The concerted effect of these processes fosters an approximate matching relation in commonly used concurrent procedures.     

Functional classes and equivalence relations

Three adult subjects were taught a set of two-choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within-class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two-choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within-class conditional relations after the equivalence tests.     

职场排斥对培训行业员工建言行为的影响——有调节的中介作用模型

研究采用问卷法,以安徽、天津的培训机构中的401名在职员工为研究对象,以组织支持感作为中介变量,以积极心理资本作为调节变量,从资源保存理论的视角探讨了职场排斥对员工建言行为的影响。研究结果表明:(1)职场排斥对员工的建言行为具有负向预测作用,职场排斥水平越高,其建言行为水平越低。(2)组织支持感在职场排斥与建言行为之间起中介作用,职场排斥通过组织支持感影响员工的建言行为。(3)组织支持感的中介作用受到积极心理资本的调节,积极心理资本会增强组织支持感的中介作用。     

A new approach to the formation of equivalence classes in pigeons

Four pigeons were given simultaneous discrimination training with visual patterns arbitrarily divided into two sets, with the stimuli in one set designated A1, B1, C1, and D1 and those in the other set designated A2, B2, C2, and D2. In sequentially introduced training phases, the pigeons were exposed to a series of reversals to establish AB and then CD equivalences. In subsequent testing sessions, a subset of stimuli from one set served as positive stimuli and those from the other set as negative stimuli on training trials, and transfer of the reinforced relation to other members of the sets was tested with nonreinforced probe trials. The pigeons were trained further on AC and BD equivalences and then were tested for the emergence of untrained AD and BC equivalences. Two of the 4 pigeons exhibited the emergence of one of these untrained equivalences, evidence for the emergence of transitive relations. This finding suggests that the pigeons established three-member functional equivalence classes by incorporating separately trained multiple equivalence relations. Repeated reversal training and probe testing enabled us to explore the formation and expansion of functional equivalence classes in pigeons.