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.     

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.     

A forced-choice study of edge detectors in the human visual system

Psychophysical studies using masking procedures to investigate the possible existence of edge detectors in the human visual system have typically been flawed by methodological errors and omissions that make their findings uninterpretable. An example of such a study is given and evaluated, and a replication of that study, using a spatial forced-choice methodology, is reported in detail. The results of this replication are shown to contradict the critical findings of the earlier study; furthermore, it is suggested that any ambiguities in the results of this replication can be interpreted in terms of methodological and procedural factors, rather than in terms of higher-order neurological constructs. Finally, a further test of this methodological interpretation is proposed.     

Recognition memory and attentional selection: serial scanning is not enough

In two experiments, using memory sets of up to 10 letters, the response competition paradigm was employed to investigate the extent to which extraneous visual stimuli interfere with or affect the process of memory search. It was assumed that if selective attention could exclude the effect of noise letters from a Sternberg-type memory comparison process, then there would be an increase in intercept for the reaction time-set size functions but no increase in slope. This result was obtained. However, a large difference in response times to both positive and negative set targets was found when the accompanying noise letters indicated a competing response, as opposed to when they indicated the same response as the target. This implies rapid identification of the nature of both target and noise, independent of a serial comparison process. A modification of a dual process model (Juola, Fischler, Wood, & Atkinson, 1971) in which stimuli activate a familiarity value independent of memory search was suggested to account for these results.     

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。