情绪韵律调节情绪词识别的ERP研究

采用韵律/词汇干扰范式和延迟匹配任务, 通过两个ERP实验, 考察了汉语口语中情绪韵律能否、以及如何调节情绪词的识别。实验一中, 不同类型的情绪韵律分组呈现, ERP结果显示, 同与情绪韵律效价一致的情绪词相比, 与情绪韵律效价不一致的情绪词诱发了走向更负的P200、N300和N400成分; 实验二中, 不同类型的情绪韵律随机呈现, 上述效价一致性效应依然存在。实验结果表明, 情绪韵律能够调节情绪词识别, 主要表现在对情绪词的音韵编码和语义加工的双重易化上。     

Generalization of delayed matching to sample following training at different delays

Four groups of pigeons were trained to perform a delayed matching-to-sample task with a single delay of 0, 2, 4, or 6 s from the outset of training. The longer the training delay, the more sessions were required for all birds to reach the same level of response accuracy. Following initial training, five test sessions that included nonreinforced trials with delay intervals of 0, 2, 4, 6, 8, and 10 s were interspersed between training sessions. Unlike typical forgetting functions in which accuracy decreases monotonically with increasing delay, the forgetting functions from test sessions resembled generalization gradients with the peak of the functions occurring at the training delay. Following additional training for all birds with a 0-s delay, forgetting functions decreased monotonically with increasing delay. The results suggested that remembering can be trained at a specific delay interval, and generalizes to similar delay intervals. Generalization along the temporal dimension of delay may contribute to typical forgetting functions in which accuracy decreases from 0-s delay.     

Temporal discounting: basic research and the analysis of socially important behavior

Recent basic research on human temporal discounting is reviewed to illustrate procedures, summarize key findings, and draw parallels with both nonhuman animal research and conceptual writings on self-control. Lessons derived from this research are then applied to the challenge of analyzing socially important behaviors such as drug abuse, eating and exercise, and impulsiveness associated with attention deficit hyperactivity disorder. Attending to the broader temporal context in which behavior occurs may aid in the analysis of socially important behavior. Applying this perspective to the study of behavior in natural environments also highlights the importance of combining methodological flexibility with conceptual rigor to promote the extension of applied behavior analysis to a broader array of socially important behaviors.     

Self-control and the preference for delayed reinforcement an example in brain injury

We investigated the effects of a concurrent physical therapy activity (keeping the hand open) during delays to reinforcement in an adult man with acquired brain injuries. Once a relatively stable level of hand-open behavior was obtained, the participant was asked to choose between a small immediate reinforcer and a larger delayed reinforcer contingent on keeping the hand open at greater-than-baseline duration. Afterwards, the participant was asked to select between a larger delayed reinforcer with no hand-open requirement and the identical larger delayed reinforcer with a progressively increasing hand-open requirement. Results suggest a shift in preference to larger delayed reinforcers and an eventual preference for the hand-open requirement option.     

Molar optimization versus delayed reinforcement as explanations of choice between fixed-ratio and progressive-ratio schedules.

In a discrete-trials procedure, pigeons chose between a fixed-ratio 81 schedule and a progressive-ratio schedule by making a single peck at the key correlated with one or the other of these schedules. The response requirement on the progressive-ratio schedule began at 1 and increased by 10 each time the progressive-ratio schedule was chosen. Each time the fixed-ratio schedule was chosen, the requirement on the progressive-ratio schedule was reset to 1 response. In conditions where there was no intertrial interval, subjects chose the progressive-ratio schedule for an average of about five consecutive trials (during which the response requirement increased to 41), and then chose the fixed-ratio schedule. This ratio was larger than that predicted by an optimality analysis that assumes that subjects respond in a pattern that minimizes the response-reinforcer ratio or one that assumes that subjects respond in a pattern that maximizes the overall rate of reinforcement. In conditions with a 25-s or 50-s intertrial interval, subjects chose the progressive-ratio schedule for an average of about eight consecutive trials before choosing the fixed-ratio schedule. This change in performance with the addition of an intertrial interval was also not predicted by an optimality analysis. On the other hand, the results were consistent with the theory that choice is determined by the delays to the reinforcers delivered on the present trial and on subsequent trials.     

USING ABERRANT BEHAVIORS AS REINFORCERS FOR AUTISTIC CHILDREN

In a series of experiments, we assessed the efficacy of using autistic children's aberrant behaviors as reinforcers to increase their correct task responding. In Experiment 1, reinforcer conditions of stereotypy, food, and varied (food or stereotypy) were compared. In Experiment 2, the conditions were delayed echolalia, food, and varied (food or delayed echolalia), and in Experiment 3, perseverative behavior was compared with stereotypy and food as potential reinforcers. A multielement design was used for all comparisons, and side-effect measures were recorded during and after teaching sessions as well as at home. Results indicated that, in general, task performance was highest when brief opportunities to engage in aberrant behaviors were provided as reinforcers. Edibles were associated with the lowest performance. Furthermore, no negative side effects (e.g., an increase in aberrant behaviors) occurred. The results are discussed in terms of suggesting a more pragmatic treatment approach by addressing the contingent use of autistic children's aberrant behaviors as reinforcers.     

Characteristics of forgetting functions in delayed matching to sample

Performance of pigeons in delayed matching-to-sample procedures was measured in terms of an index of discriminability derived from the difference between logarithms of ratios of choice responses to comparison stimuli following the different sample stimuli. Forgetting functions that plotted discriminability as a function of delay-interval duration were well described by a simple negative exponential function with two parameters, one describing initial discriminability of sample stimuli at zero delay (log d₀) and the other describing rate of decrement in discriminability with increasing delay-interval duration (b). With the difference between wavelength values of the comparison stimuli held constant, a large difference between wavelengths of the sample stimuli resulted in a higher log d₀ value than that for a small difference between sample stimuli, without changing the rate of decrement in discriminability, b. An increase in the fixed-ratio requirement for sample-key responding produced an increase in log d₀ without affecting b, and interpolation of ambient illumination in the delay interval increased b without influencing log d₀. Both parameters changed when intertrial-interval duration was varied. The result of variation in the point of interpolation of ambient illumination in the delay interval indicated that levels of discriminability at longer delays were independent of discriminability levels at earlier delays, consistent with the properties of the exponential function. Functions relating performance to delay-interval duration were suggested to have two characteristics: discriminability of the sample stimuli in the absence of a delay between the stimuli and the behavior they occasion, and rate of attenuation in discriminability with increasing delay-interval duration.     

Sample-duration effects on pigeons' delayed matching as a function of predictability of duration

Three experiments assessed the impact of sample duration on pigeons' delayed matching as a function of whether or not the samples themselves signaled how long they would remain on. When duration was uncorrelated with the sample appearing on each matching trial, the typical effect of duration was observed: Choice accuracy was higher with long (15-s) than with short (5-s) durations. By contrast, this difference either disappeared or reversed when the 5- and 15-s durations were correlated with the sample stimuli. Sample duration itself cued comparison choice by some birds in the latter (predictable) condition when duration was also correlated with the reinforced choice alternatives. However, even when duration could not provide a cue for choice, pigeons matched predictably short-duration samples as accurately as, or more accurately than, predictably long-duration samples. Moreover, this result was observed independently of whether the contextual conditions of the retention interval were the same as, or different from, those of the intertrial interval. These results strongly support the view that conditional stimulus control by the samples is partly a function of their conditioned reinforcing properties, as determined by the relative reduction in overall delay to reinforcement that they signal.     

The choose-short effect and trace models of timing

The tuned-trace multiple-time-scale (MTS) theory of timing can account both for the puzzling choose-short effect in time-discrimination experiments and for the complementary choose-long effect. But it cannot easily explain why the choose-short effect seems to disappear when the intertrial and recall intervals are signaled by different stimuli. Do differential stimuli actually abolish the effect, or merely improve memory? If the latter, there are ways in which an expanded MTS theory might explain differential-context effects in terms of reduced interference. If the former, there are observational and experimental ways to determine whether differential context favors prospective encoding or some other nontemporal discrimination.     

跨感觉通路ERP注意成分的研究

采用提高了非注意纯度的“跨通路延迟反应”实验模式,研究跨通路注意的事件相关电位（ＥＲＰ）成分,以注意ＥＲＰ减去非注意ＥＲＰ的早期差异负波（Ｎｄ１）为主要分析对象。被试者为１２名青年正常人。结果发现：①听觉偏差刺激、视觉标准与偏差刺激皆在其特异性感觉区域的头皮部位,观察到注意引起Ｎ１波幅增大的现象。Ｎｄ１的起始时间与注意Ｎ１相同,而早于非注意Ｎ１,支持注意的早期选择学说;②听觉与视觉偏差刺激产生的Ｎｄ１最大峰分布在它们各自的初级感觉投射区,而标准刺激诱发的Ｎｄ１最大峰却分布于额部,表明跨通路选择性注意对偏差刺激的加工部位主要是通路特异性的,而对标准刺激的加工部位则主要是通路上的。作者据此针对选择性注意中长期争论问题进一步提出,注意的选择性发生时程的早晚可因刺激条件而异,信息过滤器的位置具有可塑性。