Associations in Pavlovian conditioned inhibition

Two experiments with rat subjects used a variety of transfer tests to examine the associations learned when Pavlovian inhibition is established by an A+, AX− paradigm. Experiment 1 found in a conditioned suppression situation that inhibition conditioned to X with one exciter (A) readily transferred to another exciter (B) which had been paired with the same shock US. Transfer occurred even when the response to A had been extinguished prior to testing with B. However, X did not inhibit a general activity response produced by a B which had been subsequently paired with a food US. Experiment 2 employed a Pavlovian conditioning situation in which A and B, when separately paired with the same food US, evoked dissimilar responses. Nevertheless, an inhibitor trained in an A+, AX− paradigm successfully inhibited the different response evoked by B. However, such an X did not inhibit the behaviors acquired by A or B when they were subsequently paired with a shock US. The transfer of Pavlovian inhibition across conditioned stimuli and responses but not across unconditioned stimuli is consistent with the notion that a conditioned inhibitor acts to prevent activation of a US representation which would normally be activated by conditioned exciters.     

An analysis of two central stages underlying responding to personality items: The self-referent decision and response selection

A technique for isolating substages in a processing sequence (Sternberg, 1969) was used to examine two central stages in a postulated model of responding to personality items. The Self-Referent Decision (SRD) stage, where item content is compared to stored memory elements, and the Response Selection Stage, where the output of the SRD is mapped into available response alternatives, were analyzed to determine if they could be seen as separate stages. Results indicated that a modular model that viewed these two stages as being separate was supported. These results were also discussed in relation to existing models of item responding processes and the dichotomous/Likert response format issue.     

Electrocortical signs of arousal in response to darkness and the assessment of type A behavior in professional drivers with and without cardiovascular disease

Background and Aims  In night driving, the fatal accident rate is about four times that in daytime. There is a lack of published studies of the effect of darkness on electrocortical responses in professional drivers (PD). Aim: Assessing relations between electroencephalographic (EEG) reactions to enforced darkness reminiscent of night driving, and untoward behavioral response patterns, notably Type A behavior. Methods  PD: 13 with ischemic heart disease, 12 hypertensives (HTN), 10 borderline hypertensives and 34 normotensives, and 23 non-PD controls. Five minutes of electroencephalographic recording with eyes closed, and subsequently 3 minutes exposure to darkness. EEG parameters were: alpha abundance, amplitude and frequent. Type A behavior (TAB) was assessed by observation and by questionnaire. Results  Alpha abundance diminished significantly for darkness compared to spontaneous recording for all groups. No between-group differences were found for EEG. There were no significant differences in EEG between drivers with IHD or HTN taking versus not taking centrally active β-blockers. Drivers with IHD were the only group to show significant increase in dominant α frequency at darkness. The IHD group also had the highest TAB questionnaire scores and the heaviest exposure to professional driving. Type A scores were significantly correlated with dominantt alpha frequency during darkness. Low availability of attachment and special driving hazards best predicted TAB scores in driven. There was a significance between group difference with respect to Symbolic Aversiveness at the work place comparing each driver group with the non-PD control group. Conclusions  Exposure to darkness reminiscent of night driving can elicit central arousal, in conflict with circadian rhythm, and in combination with other driving hazards which contribute to symbolic aversiveness, the essence of driving. And low availability of social attachment could contribute to sustained, and in turn to the development of Type A behavior in professional drivers.     

Ⅱ型糖尿病患者的行为特征研究

使用修订行为特征问卷调查了１１２名Ⅱ型糖尿病患者和１４７名健康对照组。结果表明： １．男性患者比健康人更加抑郁;２．女性患者比健康人更加焦虑、抑郁和愤怒;３．不论是男性 还是女性,此问卷可显著地区分这两组,越抑郁的人,越不焦虑的人,越缺少合理化这种心理 防御机制的人,越可能是糖尿病患者。结合其它的研究结果,认为存在着Ⅱ型糖尿病易感性 行为特征,主要表现为：高抑郁;低焦虑;对应激的唤醒水平低;不善于使用心理防御机制来 保护和伪装自己;寻找一些有趣的事情：回避痛苦事件;不善于延迟的满足,要求马上得到满 足;注意易分散等。     

Tests for linear trend in the smallest eigenvalues of the correlation matrix

A test for linear trend among a set of eigenvalues of a correlation matrix is developed. As a technical implementation of Cattell's scree test, this is a generalization of Anderson's test for the equality of eigenvalues, and extends Bentler and Yuan's work on linear trends in eigenvalues of a covariance matrix. The power of minimumx ² and maximum likelihood ratio tests are compared. Examples show that the linear trend hypothesis is more realistic than the standard hypothesis of equality of eigenvalues, and that the hypothesis is compatible with standard decisions on the number of factors or components to retain in data analysis.This work was supported by National Institute on Drug Abuse Grants DA01070 and DA00017. The assistance of Maia Berkane and several anonymous reviewers is gratefully acknowledged.     

On the mean and variance of the tetrachoric correlation coefficient

Estimates of the mean and standard deviation of the tetrachoric correlation are compared with their expected values in several 2 × 2 tables. Significant bias in the mean is found when the minimum cell frequency is less than 5. Three formulas for the standard deviation are compared and guidelines given for their use.This research was performed when the first author was on leave at the University of California at Los Angeles and was supported in part by NIH Special Research Resources Grant RR-3. The second author was also supported by NIH Fellowship 5 F22 GM00328-02.     

On the relationship between the psychological environment and the development of individual differences in abilities

Some previous attempts at dimensionalizing human psychological environments are briefly considered. The problem is reformulated within the context of the development of dimensions of individual differences in abilities. The human psychological environment is viewed within the context of general systems theory. The latter permits an integrated view with respect to dimensions of the psychological environment and dimensions of individual differences within a developmental context. Critical in this formulation is the idea that, within the framework of the development of individual differences, it is of value to postulate the dimensions of the psychological environment as isomorphic to dimensions of individual differences.     

An identifiable model of two-stage learning

An eleven-parameter model for two-stage learning is developed. The model's principal advantage over extant two-stage models is that its parameter space is completely identifiable, thereby eliminating the tedious procedure of locating acceptable identifying restrictions. Identifiability is achieved by defining the model over a slightly modified outcome space. Following the identifiability proof, the necessary statistical machinery for parameter estimation, goodness-of-fit analyses, and hypothesis testing is presented. These latter developments are illustrated with data from an adult cued recall experiment and a free recall experiment with elementary school children.     

Prospective versus retrospective coding of samples of stimuli,responses, and reinforcers in delayed matching with pigeons

Pigeons' performance with samples of stimuli (red and green), number of responses (1 and 20), and reinforcers (food and no food) was assessed in a matching-to-sample preparation. Samples of red, 20 responses, and food were each associated with the red comparison stimulus; samples of green, 1 response, and no food were each associated with the green comparison stimulus. Interest focused on whether physically different samples associated with the same comparison stimulus each establish a unique memorial representation embodying the physical attributes of the sample (retrospective coding), or whether they activate a unitary memorial representation embodying an instruction for test responding (prospective coding). In the first experiment, accuracy of choice responding was independent of whether successive sample presentations within a trial involved the same physical sample or physically different but associatively identical samples. A second experiment revealed that, in contrast to other matching preparations, accuracy was not reduced when sample elements were compounded during presentation. It was concluded that physically different samples which are associated with the same comparison stimulus are coded prospectively in terms of an instruction for choice responding.     

Sequential response bias in randomized response sequences: A computer simulation

In this study sequential bias in randomized response sequences is simulated by computer. The computer model assumes that response bias is composed of two components. The first is a repetition avoidance tendency, which is simulated by a memory search through the seven most recently produced responses, and the second is a repetition tendency for the two most recently produced responses. This repetition tendency is assumed to be related to the better availability of recently produced responses. Both processes together give a reasonable approximation of human subjects' data.The results can be explained by the assumption that subjects try to control perseveration tendencies by using a comparison-based memory search mechanism.