Within-session Response Patterns On Conjoint Variable-interval Variable-time Schedules

Operant responding often changes within sessions, even when factors such as rate of reinforcement remain constant. The present study was designed to determine whether within-session response patterns are determined by the total number of reinforcers delivered during the session or only by the reinforcers earned by the operant response. Four rats pressed a lever and 3 pigeons pecked a key for food reinforcers delivered by a conjoint variable-interval variable-time schedule. The overall rate of reinforcement of the conjoint schedule varied across conditions from 15 to 480 reinforcers per hour. When fewer than 120 reinforcers were delivered per hour, the within-session patterns of responding on conjoint schedules were similar to those previously observed when subjects received the same total number of reinforcers by responding on simple variable-interval schedules. Response patterns were less similar to those observed on simple variable-interval schedules when the overall rate of reinforcement exceeded 120 reinforcers per hour. These results suggest that response-independent reinforcers can affect the within-session pattern of responding on a response-dependent schedule. The results are incompatible with a response-based explanation of within-session changes in responding (e.g., fatigue), but are consistent with both reinforcer-based (e.g., satiation) and stimulus-based (e.g., habituation) explanations.     

Within-session changes in responding during concurrent schedules with different reinforcers in the components.

Rats and pigeons responded on several concurrent schedules that provided different reinforcers in the two components (food and water for rats, Experiment 1; wheat and mixed grain for pigeons, Experiment 2). The rate of responding and the time spent responding on each component usually changed within the session. The within-session changes in response rates and time spent responding usually followed different patterns for the two components of a concurrent schedule. For most subjects, the bias and sensitivity to reinforcement parameters of the generalized matching law, as well as the percentage of the variance accounted for, decreased within the session. Negative sensitivity parameters were sometimes found late in the session for the concurrent food-water schedules. These results imply that within-session changes in responding could cause problems for assessing the validity of quantitative theories of concurrent-schedule responding when the components provide different reinforcers. They question changes in a general motivational state, such as arousal, as a complete explanation for within-session changes in responding. The results are compatible with satiation for, or sensitization-habituation to, the reinforcers as explanations.     

Quantification of rats' behavior during reinforcement periods

What is treated as a single unit of reinforcement often involves what could be called a reinforcement period during which two or more acts of ingestion may occur, and each of these may have associated with it a series of responses, some reflexive, some learned, that lead up to ingestion. Food-tray presentation to a pigeon is an example of such a “reinforcement period.” In order to quantify this behavior, a continuous-reinforcement schedule was used as the reinforcement period and was chained to a fixed-ratio schedule. Both fixed-ratio size and reinforcement-period duration were manipulated. Rats were used as subjects, food as reinforcement, and a lever press as the operant. Major findings included (a) a rapid decline in response rates during the first 15 to 20 seconds of the reinforcement periods, and (b) a strong positive relationship between these response rates and the size of the fixed ratio. Also revealed was a short scallop not normally found in fixed-ratio response patterns, whose length was a function of fixed-ratio size and reinforcement-period duration. It is suggested that rapidly fluctuating excitatory processes can account for many of these findings and that such processes are functionally significant in terms of behavioral compensation.     

Feedback effects on sequential ordering in humans

Under various feedback conditions, 38 college undergraduates were asked to rearrange abstract graphic characters on a computer screen, placing them in arbitrarily designated “correct” sequences. Two sets of seven horizontally arrayed stimuli were used. In Experiment 1, subjects in Group 1 learned to arrange the first set under Selection Feedback in which a “+” appeared above each character after it was selected in the correct order and to arrange the second set under Order Feedback in which a correct response produced a copy of the character in its correct ordinal position at the top of the screen. For Group 2 the order of these conditions was reversed. In Experiment 2, for subjects in Group 3, correct responses produced neither of these types of feedback. Subjects in Group 4 received Order Feedback only until the first set was correctly ordered once. Order Feedback was more effective than Selection Feedback during initial acquisition of the first set but not during maintenance; no differences were found for the second set. Only 2 of 9 subjects successfully put the characters in correct sequential order under the No Feedback condition. When, in Experiment 2, Order Feedback was eliminated after the first correctly arranged sequence, the steady-state criteria were met more slowly than in Experiment 1.     

3-6年级小学生师生关系:结构、类型及其发展

本研究采用师生关系教师评定量表,由14名班主任教师对498名3-6年级学生与教师的关系进行评价.结果表明:(1)师生关系量表具有较好的信度和效度,师生关系特点主要表现在冲突性、亲密性和反应性三个维度上.(2)快速聚类分析的结果表明,3-6年级学生的师生关系可划分为3种类型:冷漠型、冲突型、亲密型,其分布比例分别为23.0%、33.7%、43.3%.(3)师生关系随学生年级增长而变化.在师生关系各维度及总分上,存在显著的年级差异.随年级的上升,积极师生关系类型的比例逐渐下降,而消极师生关系类型的比例逐步上升.     

大学生气质类型、父母教养方式与孤独感的关系研究

采用量表法以349名大学生为被试研究了气质类型、父母教养方式和孤独感的关系.(1)差异检验表明:女性大学生的亲情孤独感、总体孤独感多于男生,且气质类型上更情绪化;城市大学生的社会性得分显著高于来自乡村大学生;在爱情孤独和总体孤独感上存在显著的专业差异,理工类大学生体验到更多的孤独感尤其是爱情孤独感.(2)相关分析表明:大学生孤独感的各个维度与其气质类型中的社会性以及父母教养方式中的大多因素显著相关.(3)回归分析进一步表明:母亲情感温暖对总体孤独感有显著预测作用;母亲情感温暖、父亲严惩、母亲干涉保护对亲情孤独感因子有显著预测作用;社会性、父亲严惩对爱情孤独感因子有显著预测作用;母亲情感温暖、母亲干涉保护、父亲干涉对社交孤独感因子有显著预测作用.     

3～6年级学生及其教师对师生关系知觉的比较研究

采用师生关系学生知觉和教师知觉问卷,分别由508名3~6年级学生及其16名班主任教师对两者之间的关系进行评价,结果表明:(1)教师和学生知觉的师生关系具有相似的结构成分:亲密性、冲突性和反应性;(2)学生知觉到的师生关系与教师知觉到的师生关系特点有显著的不同:相对于教师而言,4~6年级学生知觉到的师生关系更为消极;而3年级学生知觉到的师生关系则更为积极.(3)快速聚类分析的结果表明,教师知觉和学生知觉的师生关系可以聚为两种相同的类型:亲密型和冲突型.教师和学生知觉类型一致的比例为62.5%;不一致类型的比例为37.5%.(4)在师生关系的类型上,三年级学生知觉到的亲密型比例显著高于教师知觉,而冲突型比例则显著低于教师知觉;六年级学生与此相反.     

Manipulation and force as sexual coercion tactics: conceptual and empirical differences

This study examines the relationship between perpetrator characteristics, situational characteristics, and type of sexual coercion tactics used to obtain sexual contact (including sexual intercourse) with an unwilling partner. Men who used manipulation or force were compared to each other and to men who engaged in only consensual sex. Participants were college men drawn from the first wave of a 5-year longitudinal study. Stepwise discriminant function analyses, univariate analyses of variance (ANOVA), and chi(2) analyses tested group differences. As predicted, men who used force reported more childhood sexual abuse, witnessed more domestic violence, were more accepting of male violence, and were less likely to endorse love as a motive for sex than men in both the manipulation and consent groups. Men in the force group were also more likely to have had a casual relationship with the woman, and to be drinking and also intoxicated during the coercive incident than men in the manipulation group. Hypothesized differences between men who used force and manipulation regarding parental physical punishment, traditional gender role attitudes, delinquency, hedonistic and dominance motives for sex, prior sexual contact, and the length of the relationship were not supported. The results suggest that types of tactic used in sexual assaults can be distinguished on the basis of person and situational variables and that knowledge of these differences can facilitate future research, as well as rape deterrent and intervention programs.