Concept identification: Effect of the intertrial interval on the efficacy and consistency of information processing

Two experiments following identical procedure except for the feedback duration (respectively, 2 sec and 1.5 sec) and the intertrial interval (respectively, 1 sec and 3 sec) are compared with respect to three sequential statistics whose theoretical interpretation is related to the degree of optimality of information processing. The results indicate that the values of the theoretical parameters representing the efficiency of information processing, the consistency of trial-by-trial decisions, and the efficacy of reinforcement are greater in the 3-sec interval condition. This is interpreted as a tentative explanation of the well-known effect of intertrial interval on the difficulty of the task with respect to the mean number of trials to criterion.     

The effect of feedback stimuli on contextual fear depends upon the length of the minimum intertrial interval

The present experiments investigated the effects of manipulation of the minimum intertrial interval (ITI) on the ability of a feedback stimulus to reduce the amount of fear conditioned to the shock context. In Experiment 1, we found that animals exposed to yoked shock with a feedback stimulus were equivalent to animals which received escapable shock, and both these groups showed less fear of the shock context than did yoked animals not given feedback, when a minimum ITI of 60 s was used. This replicated the effect of feedback on contextual fear conditioning. However, animals exposed to yoked shock with a feedback stimulus but for whom the minimum ITI was 5 s showed as much fear of the context as yoked animals not given feedback. Experiment 2 assessed whether this difference was solely due to the lower minimum ITI resulting in more fear than the 60-s minimum ITI, or whether the lower minimum ITI precluded the effect of feedback. The former possibility was discounted. Thus, these studies demonstrate that a relatively long minimum ITI is essential for the observance of a feedback effect on fear of the shock context.     

A phoneme-grapheme feedback consistency effect

Recent studies examining the feedback consistency effect have been criticized for poor item selection (Peereman, Content, & Bonin, 1998). In the present study, an experiment was run with a new set of items, in which feedback consistency was manipulated at a phoneme-grapheme level. The results suggested that participants responded faster to feedback-consistent words than to feedback-inconsistent words. This was despite the feedback-consistent and feedback-inconsistent word groups’ being matched on many other dimensions, including word frequency and subjective orthographic frequency. These results may differ from those of previous studies, since previous studies in English have measured feedback consistency at the rime-body level.     

Triadic consistency and false heart-rate feedback

Subjects viewed slides of the Rorschach cards while listening to heart sounds that were supposedly but not actually their own. For some of the subjects the heart rate increased when they were exposed to the five achromatic cards and for some subjects the heart rate increased when they were exposed to the five chromatic cards. In addition, some subjects were told that increased heart rate was a sign of mental health (positive condition), and some that the increased heart rate was a sign of mental abnormality (negative condition) Since the heart-rate increase (behavior) and Rorschach cards associated with the increase (attitude object) are connected by a positive causal relation, triadic theory predicts that the sign of the heart-rate increase should generalize to the associated cards (i e, be positive in the positive condition and negative in the negative condition) An analysis of variance revealed such an overall significant effect Closer examination of the data, however, revealed that the triadic effects were not unambiguously occurring when the increased heart rate was associated with achromatic cards It was suggested that in this condition the unique characteristics of the cards facilitated the generation of complicating anxiety. Supportive data for this interpretation were offered     

Effects of time and event uncertainty upon sequential information processing

Two experiments were conducted to investigate the psychological refractory period (PRP), a delay induced into the second of two reaction times (RT) when the interstimulus interval (ISI) is short. In Experiment1, time and event uncertainty were factorially varied by providing or not providing S with foreknowledge of the ISI and the order in which the two events would occur, respectively. ISIs of0, 50, 100, 200, and400 msec were used. Time and event uncertainty produced independent degradation of both RTs. Also, the second RT (RT ₂ ) was delayed at50 msec ISI when both time and event certainty were present. Experiment 2 attempted to replicate this latter finding using ISIs of0, 25, 50, 75, and100 msec. Delays in RT ₂ were found for the middle three values of ISI. These results were interpreted as supporting a modified single channel theory of the PRP.     

Effects of the temporal relationship of feedback and stimulus information upon discrimination-learning strategies

Second grade Ss and college students were tested under three conditions of the temporal relationship of feedback and stimulus information. In one condition (/+3) feedback was delivered immediately upon S's response while the stimuli were still in view. In another (/0) feedback was also immediate but stimuli were extinguished immediately upon S's response. In the third condition (/?3), stimuli were extinguished immediately upon response and feedback was delayed 3 sec. Major findings among the children were (a) Ss of all conditions coded information at the same (high) average efficiency, (b) Ss of conditions /0 and /?3 recoded with significantly less efficiency than those of /+3, and (c) Ss in condition /+3 manifested primarily efficient information-processing strategies, those in condition /0 showed intermediate performance, and those of condition /?3 showed relatively primitive stereotyped behavior. Among adult Ss performance was uniformly high with little effect on any response measure investigated.     

Secondhand information and social judgment

This research investigates how secondhand impressions of other people differ from those based on firsthand information. It was hypothesized that secondhand impressions are often more extreme because secondhand accounts of another person's actions frequently fail to convey adequately the role of mitigating circumstances and situational constraints in producing that person's behavior. Experiments 1 and 2 tested this hypothesis by exposing “first generation” subjects to information about a target person, having them rate the target on several trait and attribution scales, and having them describe the target person's actions to a group of “second generation” subjects. As predicted, second generation subjects made more extreme ratings of the target than their first generation counterparts. Content analyses of the accounts transmitted by first generation subjects indicated that they did indeed underemphasize various situational qualifications of the target persons' behavior. Experiment 3 extended these findings by demonstrating that people's impressions of someone they have often heard about from a friend (but never met) are more extreme than their friends' more informed impressions.     

The effects of feedback consistency and feedback favorability on self-perceived task competence and perceived feedback accuracy

The present study, employing a 2 × 2 true-experimental design and regression analyses assessed the main and interactive effects of feedback consistency (consistent vs inconsistent), and feedback favorability (acceptable vs superior), for feedback given at two time periods on measures of perceived feedback accuracy and self-perceived task competence. Among the study's findings were that (a) the perceived accuracy of feedback at the second period was a function of the favorability of feedback received at the first time period, (b) the self-perceived task competence levels of subjects were jointly determined by the favorability of feedback received at both time periods, and (c) the perceived accuracy of feedback was a function of its consistency. Organizational implications of the study's results are offered.     

Effect of signaling intertrial unconditioned stimuli in autoshaping

Context-unconditioned-stimulus (US) associations have been suggested as the mediator of the response decrement that occurs when extra USs are added to the intertrial intervals (ITIs) of an otherwise standard Pavlovian conditioning situation. The present autoshaping experiments were concerned with the effect of signaling those extra USs, since such signaling might be expected to lessen their ability to condition the context. Experiments 1 and 2 showed that signaling the ITI USs did reduce their detrimental effects on responding to the conditioned stimulus (CS). To determine whether that reduction was due to an impact of signaling on the target-CS-US association or on performance to the target-CS, Experiment 3 examined responding to differentially trained CSs in a common context, as well as responding to identically trained CSs in differentially trained contexts. Whether the CS was tested in a context of relatively high or low associative strength, more responding occurred to the CS trained with signaled, as compared with unsignaled, ITI USs; further, there was more responding to that CS in the more highly valued context. The pattern of results suggests that contextual value does interact with CS-US learning and may also affect performance to the CS.     

工作记忆的存储时间及目标时距对时间知觉的影响

本研究操作记忆信息与计时开始之间的时间间隔（ISI）和目标时距,探讨工作记忆影响时间判断的灵活性。被试首先记忆一个客体,然后在每个trial的最后判断测试刺激是否与记忆项相同;在延迟阶段,被试完成时间判断任务,即判断相继出现的两个刺激的时距哪个更长（或更短）。时间任务中的一个刺激与记忆内容完全相同,相应的另一个刺激与记忆内容在形状和颜色上都不同。重复条件下,被试忽略第一个刺激,仅完成时间判断任务。结果发现,时间间隔（ISI）短时,记忆匹配条件下的准确率更高,匹配刺激延长了知觉的时间;但随着时间间隔的增加,工作记忆匹配对时间判断的影响降低甚至消失。并且,长或短ISI,记忆任务或重复条件下,目标时距长时,记忆匹配反而缩短了知觉的时间。研究说明工作记忆对时间判断的影响是灵活的,受到注意或工作记忆等高级认知系统的调控。     

Effect of information feedback on temporal discrimination in concurrent and post-feedback measures

College students estimated time intervals (5, 6, 7, 8, and 9 sec.) where one group (N = 20) received information feedback in terms of actual interval durations and a second group (N = 18) received no information. Theshold measures were then taken for all subjects using the method of constant stimuli (comparison stimuli of 5, 6, 7, 8, and 9 sec. and a 7-sec. standard). In addition to increased accuracy and consistency of judgments, the feedback group showed a decreasing Weber fraction during the estimation phase, while the Weber fraction for the no-feedback group increased. The feedback group retained only a slight advantage in subsequent threshold measures; group differences in difference thresholds and derived nonparametric estimates of d' were nonsignificant.