Unification of psychophysical phenomena: The complete form of Fechner’s law

Many of the laws and empirical observations of fundamental psychophysics can be unified with a single equation, which has been called the complete form of Fechner’s law. It can be shown that this law embraces both of the commonly used forms: Stevens’s and Fechner’s laws. It assumes one or the other form with appropriate values of the parameters. However, the complete equation confers an advantage beyond simply containing the classical laws. It offers greater flexibility in the representation of experimental data. It is shown that psychophysical phenomena may be represented by any number of triplets of quantities: subjective magnitude of stimulus, subjective just noticeable difference (jnd), and differential threshold. Each of the preceding quantities are functions of the physical magnitude of the stimulus. The investigator has the license to choose two of these quantities in the form he or she thinks is best; the third quantity is determined by the choice of the first two. Thus, for example, different forms of the law of sensation and different forms of the mathematical function for differential threshold may coexist with equal validity.     

中国和荷兰高智商与一般智商儿童自我概念比较研究

用瑞文测验和自我描述问卷对中国和荷兰2000多名10—15岁儿童进行调查．发现智商对自我概念有明显的影响,但中国和荷兰儿童表现出不同的特点。两国间在自我概念方面有显著性差异,中国儿童在大多数方面都显著性地低于荷兰儿童、中国高智商组儿童在学业自我概念方面与荷兰高智商组儿童的差异更为明显。     

EXTENSION DE LA PERSPECTIVE TEMPORELLE FUTURE EN RELATION AVEC LA FRUSTRATION*

By means of Nuttin's Motivational Induction Method, the intentions, plans and goals of subjects from Rwanda were collected. These motivational objects of 71 frustrated subjects (non-admitted to the university) were compared with those of 47 non-frustrated subjects (admitted to the university) regarding extension of their future time perspective (FTP). As hypothesized, FTP of frustrated subjects was more restricted than that of non-frustrated subjects (the mean extension score, in number of years, and the proportion of number of references to the near future to the number of references to the distant future). No difference was found before the occurrence of the frustrating situation. An additional analysis based on subjective frustration demonstrates that a significant relationship exists between intensity of experienced frustration and extension of FTP.     

The effect of earlier experience and reward contingencies on intrinsic motivation

The effects of task-contingent and performance-contingent extrinsic rewards upon subsequent intrinsic motivation are compared. Intrinsic motivation is measured by behavioral observation in a free time period and by rating scales. The results show, as expected, a higher rating of intrinsic motivation in the performance-contingent reward condition. The study further compares strength of intrinsic motivation in one- and two-session conditions. As hypothesized, a two-session condition, in which the subjects have a preexperience with the task without reward administration, leads to a higher rating of intrinsic motivation than a one-session condition without such a preexperience. The behavioral measure of intrinsic motivation is not significantly affected by the conditions. A post hoc analysis of the data indicates that there may be a different effect of extrinsic rewards on behavioral measures and on rating scale measures of intrinsic motivation.     

Temporal and spatial characteristics of selective encoding from visual displays

The time required for Ss to voice a target letter in a visual display was studied as a function of the spatial proximity of two kinds of noise elements (letters or disks) to the target and as a function of when the noise elements were presented following the onset of the target letter. The results were not consistent with a focusing model of attention or selective encoding. Instead, there appears to be a small area in the visual field (about 1 deg of angle) in which all stimuli are processed in detail.     

Some characteristics of selective attention in visual perception determined by vocal reaction time

Previous research had found that the accuracy with which an S could report an indicated letter or target in a briefly exposed multiletter display decreased as the number of irrelevant letters increased, and accuracy increased if the position of the target letter was indicated 150 msec before the display was presented. Iii the present experiment, these variables were reinvestigated using vocal reaction time as the dependent variable. An interpretation of the accuracy measures in terms of differential processing times was supported. The results of the two experiments were discussed in terms of a model of attentional selectivity.     

Do noise masks terminate target processing?

Much recent research in visual information processing has employed a methodology resting on the assumption that a noise mask following presentation of a target stimulus terminates processing of that target. In the absence of appropriate controls, such a methodology is viable only insofar as an erasure theory of masking is valid. However, the phenomena from which the erasure position has derived its strongest support have been subject to alternative theoretical explanations, the most general of which is that of temporal integration. The experiment reported here tested these alternatives. Twelve subjects served in a tachistoscopic study designed to determine whether the same noise field of dots could either erase a degraded target digit or facilitate target identification through temporal integration, under both forward and backward masking paradigms. This was found to be the case, and the results were interpreted as consistent with an integration theory of masking and as incompatible with an erasure conception. The results suggested that efforts to control target processing time through display of a visual noise pattern subsequent to target presentation are methodologically inadequate when devoid of some basic control operations.