Resistance to change of operant variation and repetition

A multiple chained schedule was used to compare the relative resistance to change of variable and fixed four-peck response sequences in pigeons. In one terminal link, a response sequence produced food only if it occurred infrequently relative to 15 other response sequences (vary). In the other terminal link, a single response sequence produced food (repeat). Identical variable-interval schedules operated in the initial links. During baseline, lower response rates generally occurred in the vary initial link, and similar response and reinforcement rates occurred in each terminal link. Resistance of responding to prefeeding and three rates of response-independent food delivered during the intercomponent intervals then was compared between components. During each disruption condition, initial- and terminal-link response rates generally were more resistant in the vary component than in the repeat component. During the response-independent food conditions, terminal-link response rates were more resistant than initial-link response rates in each component, but this did not occur during prefeeding. Variation (in vary) and repetition (in repeat) both decreased during the response-independent food conditions in the respective components, but with relatively greater disruption in repeat. These results extend earlier findings demonstrating that operant variation is more resistant to disruption than is operant repetition and suggest that theories of response strength, such as behavioral momentum theory, must consider factors other than reinforcement rate. The implications of the results for understanding operant response classes are discussed.     

The predicting brain: Unconscious repetition, conscious reflection and therapeutic change

Neuroscience indicates that 'repetition' is fundamental to brain function. The brain non-consciously predicts what is most likely to happen and sets in motion perceptions, emotions, behaviors and interpersonal responses best adapted to what is expected-before events occur. Predictions enable individuals to be ready 'ahead of time' so reactions occur rapidly and smoothly when events occur. The brain uses past learning as the guide for what to expect in the future. Because of prediction, present experience and responses are shaped by the past. Predictions from early life can be deeply encoded and enduring. Predictions based on the past allow for more efficient brain function in the present, but can lead to mistakes. When what is predicted does not occur, consciousness can be engaged to monitor and correct the situation. But if a perception or emotion seems reasonable for the situation, a person might not notice an error, and a maladaptive 'repetition' may remain unchanged. The author discusses how predictions contribute to psychological defenses and transference repetition, and how conscious self-reflection facilitates therapeutic change. The neuroscience of prediction indicates why, in certain cases, active engagement by the analyst may be necessary. The author makes the argument for use of a 'neuroscience interpretation'.     

Spatial modulation of repetition blindness and repetition deafness

When two identical visual items are presented in rapid succession, people often fail to report the second instance when trying to recall both (e.g., Kanwisher, 1987). We investigated whether this temporal processing deficit is modulated by the spatial separation between the repeated stimuli within both audition and vision. In Experiment 1, lists of one to three digits were rapidly presented from loudspeaker cones arranged in a semicircle around the participant. Recall accuracy was lower when repeated digits were presented from different positions rather than from the same position, as compared to unrepeated control pairs, demonstrating that auditory repetition deafness (RD) is modulated by the spatial displacement between repeated items. A similar spatial modulation of visual repetition blindness (RB) was reported when pairs of masked letters were presented visually from either the same or different positions arranged on a semicircle around fixation (Experiment 2). These results cannot easily be accounted for by the token individuation hypothesis of RB (Kanwisher, 1987; Park & Kanwisher, 1994) and instead support a recognition failure account (Hochhaus & Johnston, 1996; Luo & Caramazza, 1995, 1996).     

Derealization and repetition

The psycho-technique of "derealization" helped the majority of the German population that had been loyal to the Hitler regime to escape from their historical responsibility in 1945. The derealization of an historical era of collective history and of the corresponding phases of their individual histories saved these people the work of self transformation and opened the way to an unwitting repetition. In the unending debates around Nazi war criminal and their accomplices, the paramount issue is to refuse the "normality" of this derealization.     

听觉预测编码：对声音重复和变化的神经反应

预测编码被认为是脑与复杂环境交互的重要机制之一, 有效感知外界环境并对未来事件做出预测, 对个体生存有着至关重要的意义。人类大脑会基于感觉输入以迭代的方式持续优化表征外部环境的内部模型, 并不断预测接下来的感觉输入。以听觉模态为例, 人类及动物对声音重复和听觉变化的神经反应(如失匹配负波和刺激特异性适应)是大脑预测编码的重要体现, 表现为重复抑制和预测误差。结合人类和动物模型在此理论框架下开展跨物种研究将有助于加深我们对听觉加工, 甚至是大脑工作机制的认识。     

Young children's change in strategies of size comparison: Effects of task repetition and strategy evaluation

This study examined how young children change their strategies for size comparison. Twenty-two 5 and 6-year-old children were asked to compare the sizes of geometric figures and their strategies were observed once a week over three weeks. Half of the children were also asked to evaluate presented strategies for comparing geometric figures. It was found that over three weeks not only children who evaluated the strategies but also children who did not increased correct responses, the strategy of placing one figure on another, and the strategy of adjusting two figures by two dimensions. Although more children became aware of the effectiveness of those strategies, there was no relationship between the evaluation and use of strategies.     

Trial after trial: General processing consequences as a function of repetition and change in multidimensional sound

While there are pointers relating to the consequences of repetition, a general framework regarding the cognitive implications of processing multidimensional stimuli as a function of previous stimulus history is currently lacking. Three experiments using sounds varying in location and pitch were carried out, in which the immediate consequences of repeating or changing task-relevant and task-irrelevant attributes were orthogonally examined. A consistent pattern of data was shown, in that the magnitude of selective attention failure was larger when the task-relevant value repeated across trials, while differences between dimensions were larger when the task-relevant value changed across trials. These effects of irrelevance and dimension as a function of intertrial contingency are summarized in a model depicting the dynamic allocation of processing resource.     

Behavioral and neural analyses of connotative meaning: Word classes and rating scales

Behavioral (semantic differential) and neural (Evoked Potentials, EPs) responses were related to connotative meaning. The approach was based on Osgood's semantic analyses and dimensions of Evaluation (E), Potency (P), and Activity (A). The experimental variables were (1) the semantic class of the stimulus word (E+, E-, P+, P-, A+, A-) and (2) the dimension of the semantic scale (E, P, A) which the subject used to rate the stimulus words. These variables were experimentally combined such that on each trial the subject used a designated semantic scale to judge a specified stimulus word while brain activity was recorded. Using multivariate analyses, the effects on the EPs of stimulus word class, scale dimension, and their interaction were analyzed. The EP effects of stimulus word class were similar whether the subjects were merely saying the words or rating the words on a variety of semantic scales. Different EPs were found for six word classes, three semantic scale dimensions, and the 18 groups formed by their combination. The success rates in EP identification of (1) word class and (2) scale dimension did not depend on whether these two kinds of semantic variables involved the same or different semantic dimensions. The two kinds of semantic effects in EPs were largely independent. The behavioral data supported Osgood's results and showed that our subjects were appropriately processing the semantic information. The common analyses of data from all subjects suggest the universality of the connotative EP effects across individuals. This parallels, at the neural level, the universality of the connotative dimensions found at the behavioral level by semantic differential ratings. The EP effects imply that the neural representation of meaning is similar in different individuals.