Fixed-interval responding under second-order schedules of food presentation or cocaine injection.

Squirrel monkeys operated a key under second-order schedules in which every tenth completion of a 5-minute fixed interval resulted in either presentation of food or intravenous injection of cocaine. When a 2-second light was presented at the completion of the component fixed-interval schedules, positively accelerated responding developed and was maintained in each component. Over a tenfold range of doses of cocaine(30 to 300 microgram/kg/injection) and amounts of food (0.75 to 7.5 g/presentation); the second-order schedule of cocaine injection maintained higher average rates of responding than the second-order schedule of food presentation. Substituting saline for cocaine or eliminating food presentation decreased average rates of responding. When no stimulus change occurred at the completion of the first nine component fixed-interval schedules, but the 2-second light and food presentation or cocaine injection still occurred after the tenth component, only low and relatively constant rates of responding were maintained in each component. Patterns of responding characteristic of 5-minute fixed-interval schedules were maintained by the 2-second light paired with either cocaine injection or food presentation, though the maximum frequency of cocaine injection or food presentation was less than once per 50 minutes.     

AGGRESSION AS POSITIVE REINFORCEMENT IN MICE UNDER VARIOUS RATIO‐ AND TIME‐BASED REINFORCEMENT SCHEDULES

There is evidence suggesting aggression may be a positive reinforcer in many species. However, only a few studies have examined the characteristics of aggression as a positive reinforcer in mice. Four types of reinforcement schedules were examined in the current experiment using male Swiss CFW albino mice in a resident—intruder model of aggression as a positive reinforcer. A nose poke response on an operant conditioning panel was reinforced under fixed‐ratio (FR 8), fixed‐interval (FI 5‐min), progressive ratio (PR 2), or differential reinforcement of low rate behavior reinforcement schedules (DRL 40‐s and DRL 80‐s). In the FR conditions, nose pokes were maintained by aggression and extinguished when the aggression contingency was removed. There were long postreinforcement pauses followed by bursts of responses with short interresponse times (IRTs). In the FI conditions, nose pokes were maintained by aggression, occurred more frequently as the interval elapsed, and extinguished when the contingency was removed. In the PR conditions, nose pokes were maintained by aggression, postreinforcement pauses increased as the ratio requirement increased, and responding was extinguished when the aggression contingency was removed. In the DRL conditions, the nose poke rate decreased, while the proportional distributions of IRTs and postreinforcement pauses shifted toward longer durations as the DRL interval increased. However, most responses occurred before the minimum IRT interval elapsed, suggesting weak temporal control of behavior. Overall, the findings suggest aggression can be a positive reinforcer for nose poke responses in mice on ratio‐ and time‐based reinforcement schedules.     

1s范围视听时距认知的分段性研究

时距认知分段性指不同长度时距加工机制和表征方式不同。以往研究对1s范围时距认知分段性仍存在分歧,为此在规避以往研究局限基础上设计实验1和实验2。实验1和实验2分别采用双任务范式探讨心算任务对100ms和1000ms听、视时距比较的选择性干扰,结果表明,心算任务影响了1000ms听、视时距比较的75%差别阈限,心算加工负荷越大,75%差别阈限越大,但对100ms听、视时距比较的75%差别阈限没有影响。两项实验支持了1s范围视、听时距认知均具有分段性。     

A tuned-trace theory of interval-timing dynamics

Animals on interval schedules of reinforcement can rapidly adjust a temporal dependent variable, such as wait time, to changes in the prevailing interreinforcement interval. We describe data on the effects of impulse, step, sine-cyclic, and variable-interval schedules and show that they can be explained by a tuned-trace timing model with a one-back threshold-setting rule. The model can also explain steady-state timing properties such as proportional and Weber law timing and the effects of reinforcement magnitude. The model assumes that food reinforcers and other time markers have a decaying effect (trace) with properties that can be derived from the rate-sensitive property of habituation (the multiple-time-scale model). In timing experiments, response threshold is determined by the trace value at the time of the most recent reinforcement. The model provides a partial account for the learning of multiple intervals, but does not account for scalloping and other postpause features of responding on interval schedules and has some problems with square-wave schedules.     

A half century of scalloping in the work habits of the United States Congress

It has been suggested that the work environment of the United States Congress bears similarity to a fixed-interval reinforcement schedule. Consistent with this notion, Weisberg and Waldrop (1972) described a positively accelerating pattern in annual congressional bill production (selected years from 1947 to 1968) that is reminiscent of the scalloped response pattern often attributed to fixed-interval schedules, but their analysis is now dated and does not bear on the functional relations that might yield scalloping. The present study described annual congressional bill production over a period of 52 years and empirically evaluated predictions derived from four hypotheses about the mechanisms that underlie scalloping. Scalloping occurred reliably in every year. The data supported several predictions about congressional productivity based on fixed-interval schedule performance, but did not consistently support any of three alternative accounts. These findings argue for the external validity of schedule-controlled operant behavior as measured in the laboratory. The present analysis also illustrates a largely overlooked role for applied behavior analysis: that of shedding light on the functional properties of behavior in uncontrolled settings of considerable interest to the public.     

The long-term effect of high- and low-rate responding histories on fixed-interval responding in rats

Tell rats were given extended lever-press training on a fixed-interval (FI) 30-s food reinforcement schedule from the outset or following exposure to one or two previous reinforcement schedules. For 4 rats the previots schedule was either fixed-ratio 20, which generated high response rates, or differential-reinforcement-of-low-rate 20 s, which produced low response rates. For 4 additional rats the extended training on FI 30 s was preceded by experience with two schedules: fixed-ratio 20 followed by differential-reinforcement-of-low-rate 20 s; or the same two schedules in the reverse order. Fixed-interval response rates were initially affected by the immediately preceding schedule, but after 80 to 100 sessions, all traces of prior schedule history had disappeared. The results also showed no long-term effect of schedule history on the interfood-interval patterns of responding on the FI 30-s schedule. These results support one of the most central tenets of the experimental analysis of behavior: control by the immediate consequences of behavior.     

Effects of reinforcement history on response rate and response pattern in periodic reinforcement

Several researchers have suggested that conditioning history may have long-term effects on fixed-interval performances of rats. To test this idea and to identify possible factors involved in temporal control development, groups of rats initially were exposed to different reinforcement schedules: continuous, fixed-time, and random-interval. Afterwards, half of the rats in each group were studied on a fixed-interval 30-s schedule of reinforcement and the other half on a fixed-interval 90-s schedule of reinforcement. No evidence of long-term effects attributable to conditioning history on either response output or response patterning was found; history effects were transitory. Different tendencies in trajectory across sessions were observed for measures of early and late responding within the interreinforcer interval, suggesting that temporal control is the result of two separate processes: one involved in response output and the other in time allocation of responding and not responding.     

意向保持间隔对时间性前瞻记忆的影响

通过两个实验来探讨意向保持间隔对时间性前瞻记忆的影响。实验一仅通过嵌入前瞻目标的背景任务来操纵保持间隔,实验二通过在背景任务之前加入不同时长的填充任务来改变意向保持间隔。结果发现,(1)背景任务中的保持间隔越长,前瞻记忆成绩越差;(2)背景任务中的保持间隔和填充任务的时长对前瞻记忆的影响存在交互作用。成绩最好的为15min-2min组,最差的为15min-15min组。结果表明,背景任务和填充任务阶段对于个体保持前瞻意向可能有不同的功能。     

单维测验合成信度元分析

元分析是根据现有研究对感兴趣的主题得出比较准确和有代表性结论的一种重要方法,在心理、教育、管理、医学等社会科学研究中得到广泛应用。信度是衡量测验质量的重要指标,用合成信度能比较准确的估计测验信度。未见有文献提供合成信度元分析方法。本研究在比较对参数进行元分析的三种模型优劣的基础上,在变化系数模型下推出合成信度元分析点估计及区间估计的方法;以区间覆盖率为衡量指标,模拟研究表明本研究提出的合成信度元分析区间估计的方法得当;举例说明如何对单维测验的合成信度进行元分析。     

Spatial memory in rats after 25 hours

We investigated the time course of spatial-memory decay in rats using an eight-arm radial maze. It is well established that performance remains high with retention intervals as long as 4 h, but declines to chance with a 24-h retention interval (Beatty, W. W., & Shavalia, D. A. (1980b). Spatial memory in rats: time course of working memory and effect of anesthetics. Behavioral & Neural Biology, 28, 454-462). It is possible that 24 h reflects a genuine retention limitation of rat spatial memory. Alternatively, it may be possible to identify factors that might support memory performance even after very long delays. The current experiment was conducted to test the above two hypotheses. We evaluated performance using two intertrial intervals (24 and 48 h) and two retention intervals (1 and 25 h). Increasing the intertrial interval produced an approximately constant increase in performance for both retention intervals. This improvement is consistent with a trial-spacing effect (i.e., the superiority of spaced over massed trials). Rat spatial memory apparently lasts at least 25 h.