Within-session Changes In Responding During Concurrent Variable-interval Schedules

Five rats and 4 pigeons responded for food delivered by several concurrent variable-interval schedules. The sum of the rates of reinforcement programmed for the two components varied from 15 to 480 reinforcers per hour in different conditions. Rates of responding usually changed within the experimental session in a similar manner for the two components of each concurrent schedule. The within-session changes were similar to previously reported changes during simple schedules that provided rates of reinforcement equal to the sum of all reinforcers obtained from the concurrent schedules. The number of changeovers also changed within sessions in a manner similar to the changes in instrumental responding. These results suggest that changeovers are governed by the same variables that govern instrumental responding. They also suggest that the within-session change in responding during each component of a concurrent schedule is determined by approximately the sum of the reinforcers obtained from both components when both components provide the same type of reinforcer.     

Residence time and choice in concurrent foraging schedules

Five pigeons were trained on a concurrent-schedule analogue of the “some patches are empty” procedure. Two concurrently available alternatives were arranged on a single response key and were signaled by red and green keylights. A subject could travel between these alternatives by responding on a second yellow “switching” key. Following a changeover to a patch, there was a probability (p) that a single reinforcer would be available on that alternative for a response after a time determined by the value of λ, a probability of reinforcement per second. The overall scheduling of reinforcers on the two alternatives was arranged nonindependently, and the available alternative was switched after each reinforcer. In Part 1 of the experiment, the probabilities of reinforcement, ρ_red and ρ_green, were equal on the two alternatives, and the arranged arrival rates of reinforcers, λ_red and λ_green, were varied across conditions. In Part 2, the reinforcer arrival times were arranged to be equal, and the reinforcer probabilities were varied across conditions. In Part 3, both parameters were varied. The results replicated those seen in studies that have investigated time allocation in a single patch: Both response and time allocation to an alternative increased with decreasing values of λ and with increasing values of ρ, and residence times were consistently greater than those that would maximize obtained reinforcer rates. Furthermore, both response- and time-allocation ratios undermatched mean reinforcer-arrival time and reinforcer-frequency ratios.     

Changeover behavior and preference in concurrent schedules

Pigeons were trained on a multiple schedule of reinforcement in which separate concurrent schedules occurred in each of two components. Key pecking was reinforced with milo. During one component, a variable-interval 40-s schedule was concurrent with a variable-interval 20-s schedule; during the other component, a variable-interval 40-s schedule was concurrent with a variable-interval 80-s schedule. During probe tests, the stimuli correlated with the two variable-interval 40-s schedules were presented simultaneously to assess preference, measured by the relative response rates to the two stimuli. In Experiment 1, the concurrently available variable-interval 20-s schedule operated normally; that is, reinforcer availability was not signaled. Following this baseline training, relative response rate during the probes favored the variable-interval 40-s alternative that had been paired with the lower valued schedule (i.e., with the variable-interval 80-s schedule). In Experiment 2, a signal for reinforcer availability was added to the high-value alternative (i.e., to the variable-interval 20-s schedule), thus reducing the rate of key pecking maintained by that schedule but leaving the reinforcement rate unchanged. Following that baseline training, relative response rates during probes favored the variable-interval 40-s alternative that had been paired with the higher valued schedule. The reversal in the pattern of preference implies that the pattern of changeover behavior established during training, and not reinforcement rate, determined the preference patterns obtained on the probe tests.     

The Influence of Distress on Mothers' and Fathers' Reports of Childhood Emotional and Behavioral Problems

This study examined the effect of parental distress on mothers' and fathers' reports of children's emotional and behavioral problems. The subjects were the parents of 696 children aged 10 to 11 or 14 to 15 years living in two-parent families in the community. The study utilized an extended version of the model previously employed by Fergusson, Lynskey, and Horwood (1993) to examine the impact of maternal depression on mothers' reports of children's behavior. In the present study, the extended model was used to assess the impact of distress on reports of childhood externalizing and internalizing problems obtained from both mothers and fathers. The results suggested that distress had little influence on mothers' or fathers' reports of childhood behavior problems. It is concluded that in community studies the size of any bias in mothers' and fathers' reports of childhood behavior problems due to parental distress is likely to be very small and of little clinical significance.     

Sensitizing Medical Residents to Fantasies and Alignments in the Family: Mastering Psychosocial Skills in the Medical Encounter

In this paper, it is proposed that a) psychosocial medicine is best taught in a setting that provides technical and emotional support, while seizing for teaching only those moments when the learner is most receptive; and b) that the setting should avoid the development of a separate psychosocial skills curriculum, but should take the student where he or she is and integrate the psychosocial skills into his or her everyday biomedical practice. The paper gives specific case examples in which family based psychosocial issues were preeminent in the clinical problem-solving medical residents faced.     

关联性记忆错觉的产生与保持

两项实验对关联性记忆错觉的产生与保持进行了考察。实验结果表明,关联性记忆错觉接近学过词的回忆水平,但它的产生不随年龄的变化而变化;时间变量对关联性记忆错觉的影响不显著。此外,关联性记忆错觉不同于学过的词,在延迟加快时没有系列位置效应的产生。     

语句重音分布模式知觉

在排除语义和句法结构信息的情况下,用统计方法研究听者使用局部的韵律学线索知觉语句重音分布模式的能力;并根据知觉模式,讨论汉语中重音分类、词重音在语流中的变化以及重音在语句组织和语义表达中的作用等问题。     

Parallel lives: Community psychology in Latin America and the United States

Comparing the history of community psychology as it developed in the U.S. during the 1960s with the community psychology that developed 10 years later in Latin America, one is reminded of the title of Plutarch’s masterpice,Parallel Lives. Although there was very little contact or communication between the first community psychologists in these regions, very similar principles and orientations evolved. These similarities are particularly striking given the many ways in which the U.S. and Latin American contexts and histories differ. Since most readers are expected to be familiar with the history of community psychology as it developed in the U.S., this paper focuses primarily on the development of community psychology in Latin America in order to highlight areas of convergence as well as divergence from the U.S. experience. This paper is based on an address presented at the Fourth Biennial Conference, Society for Community Research and Action, Division 27 of the American Psychological Association, William and Mary College, Williamsburg, Virginia, 1993. The author acknowledges the valuable help received from J. R. Newbrough and from the referees in the revision of this paper.     

MFT trainee adjustment to program lifestyle stress: The TAPS scale

The 30-item Trainee Adjustment to Program Stress (TAPS) scale was developed to measure lifestyle stress of family therapy trainees. Initially, 70 items were generated from propositional statements based on four constructs. Following pilot testing, 329 out of 900 (37%) student members of the American Association for Mariage and Family Therapy (AAMFT) returned TAPS questionnaires. Internal consistency reliability analyses and principal components and factor analyses produced a final 30 item TAPS scale appropriate for use in family therapy training programs. Reliability and validity measures are reported.     

The application of the satir model of family therapy to the families in Hong Kong: A personal reflection

Practitioners in Hong Kong have shown an increasing interest in various family therapy approaches since the 1980s. This paper offers a critique of the major concepts and techniques of the Satir model applied to families in Hong Kong. Cultural considerations are examined in relation to the family structure and hierarchy, the Chinese self and self-esteem, communication patterns, and family rules. Implications for the application of the Satir model of family therapy in Hong Kong are discussed.