Objective and simulated stimulation: an empirical study of the effect of indirect suggestion on motor behavior

In an experimental investigation it is demonstrated that motor behavior-in contrast to the opinion forwarded in the literature-is not only elicitable by means of direct persuasion, but also to a great extend by mere indirect suggestion, (feigning of stimuli). A differential investigation of these effects provided evidence that reactions to feigned stimuli are highly person specific and relatively homogenous concerning the respective instruments whereas objective stimuli lead to reactions relatively specific for the respective instrument applied. The findings are interpreted as an analog on to placebo-effects in the area of motor behavior. Their extend may be seen as an argument for a stronger concern with subjective reaction tendencies in this field.     

Creating new memories that are quickly accessed and confidently held

In two experiments involving a total of 542 subjects, a series of slides depicting a burglary was shown. After the initial event, subjects were exposed to one or more narratives about the event that contained some misinformation or neutral information about four critical details. Finally, subjects were tested on their memories of what they saw, and their reaction times and confidence levels were measured. When subjects took a standard test in which the misinformation item was a possible response option, they responded very quickly and confidently when making this incorrect choice. Misled subjects responded as quickly and confidently to these "unreal" memories as they did to their genuine memories. It does not seem, then, that the misinformation effect arises from a large proportion of subjects who must resolve a conflict between two memories when they are tested, a conflict that would be expected to take time. When subjects took a modified test in which the misinformation item was not a possible response, misled subjects were as accurate as were controls, but they responded more slowly, regardless of whether they ultimately chose the right or wrong option. These findings indicate that misinformation does introduce some form of interference not detected by a simple test of accuracy.     

Supportive and problematic social interactions: A social network analysis

Assessed the number of sources of supportive and problematic social interactions in the total social network as well as the number who were the sources of consistently supportive or problematic interactions in a sample of 2nd year medical students. Number of problematic interaction sources was hypothesized to be more predictive of psychological and physical well-being than number of supportive interaction sources. Results showed that total supportive and total problematic interaction sources were equally predictive of life satisfaction. The presence of at least one individual who is a consistent source of problematic interactions was most predictive of lower life satisfaction. Results indicate the importance of studying both supportive and problematic social interactions. They also suggest that interactions with individuals that are consistently problematic may negatively impact upon well-being.     

Community psychology in Hong Kong: Past,present, and future

The expansion of mental health services during the 1960s from a single remote mental hospital to centers and clinics in mainstream communities fostered the development of community psychology in Hong Kong. Few psychologists were initially involved in the local community mental health movement, but its momentum resulted in increasing numbers of practitioner psychologists working in community-based service settings. Community psychology in Hong Kong today consists primarily of service delivery, but also includes applied research, community organization/consultation, and community education. Despite having many parallels with the American situation, key concepts underpinning the practice of community psychology in the Territory possess their own character as a reflection of nuances in the local scene. Prospects for the continued development of community psychology in Hong Kong appear favorable. Of special relevance is the field's potential contribution to a better understanding of the psychological phenomena associated with the Territory's sociopolitical transformation in 1997.     

On the logic of causally necessary and sufficient conditions: Towards a theory of motive-explanations of human actions

Research carried out under the auspices of the Bank of Sweden. Tercentenary Foundation project RJ 86/183: Basic Concepts of Procedural Law in the Light of Present-Day Philosophy of Language and Linguistics.     

Least-squares approximation of an improper correlation matrix by a proper one

An algorithm is presented for the best least-squares fitting correlation matrix approximating a given missing value or improper correlation matrix. The proposed algorithm is based upon a solution for Mosier's oblique Procrustes rotation problem offered by ten Berge and Nevels. A necessary and sufficient condition is given for a solution to yield the unique global minimum of the least-squares function. Empirical verification of the condition indicates that the occurrence of non-optimal solutions with the proposed algorithm is very unlikely. A possible drawback of the optimal solution is that it is a singular matrix of necessity. In cases where singularity is undesirable, one may impose the additional nonsingularity constraint that the smallest eigenvalue of the solution be , where is an arbitrary small positive constant. Finally, it may be desirable to weight the squared errors of estimation differentially. A generalized solution is derived which satisfies the additional nonsingularity constraint and also allows for weighting. The generalized solution can readily be obtained from the standard unweighted singular solution by transforming the observed improper correlation matrix in a suitable way.     

Reading long words embedded in sentences: informativeness of word halves affects eye movements

The possibility was explored that the informativeness of a specific region within a word can influence eye movements during reading. In Experiment 1, words containing identifying information either toward the beginning or toward the end were displayed asymmetrically around the point of fixation so that the reader was initially presented with either the informative or noninformative zone. Words were read with shorter summed initial fixation time when the reading was started from the informative zone. In Experiments 2 and 3, the target words were presented in sentences that were to be comprehended. More attention was given to the informative endings of words than to redundant endings. The latter were also skipped more often. The duration of the first fixation was not affected by information distribution within the word, whereas the second fixation duration was. The results of these experiments lend good support to the hypothesis of immediate lexical control over fixation behavior and to the notion of a convenient viewing position.     

A componential model for mental addition

A componential model capable of representing simple and complex forms of mental addition was proposed and then tested by using chronometric techniques. A sample of 23 undergraduate students responded to 800 addition problems in a true-false reaction time paradigm. The 800 problems comprised 200 problems of each of four types: two single-digit addends, one single- and one double-digit addend, two double-digit addends, and three single-digit addends. The results revealed that the columnwise product of addends, a structural variable consistent with a memory network retrieval process, was the best predictor of mental addition for each of the four types of problem. Importantly, the componential model allowed estimation of effects of several other structural variables, e.g., carrying to the next column and speed of encoding of digits. High levels of explained variance verified the power of the model to represent the reaction time data, and the stability of estimates across types of problem implied consistent component use by subjects. Implications for research on mental addition are discussed.     

Twenty-four-hour sleep-wake patterns in a nursing home population

Sleep-activity patterns were objectively recorded over a 24-hr period in 19 elderly nursing home residents. On average, both sleep and wake times were observed during every hour of the 24 recorded hours; however, the sleep pattern of the residents was fragmented so that they rarely experienced even a single hour of consolidated time spent sleeping. It is hypothesized that several independent factors, including compensation for lost sleep, increased total time in bed, weakening of social constraints, and deterioration of the circadian sleep-wake rhythm, are interacting to produce this increase in sleep fragmentation.     

Comparative analysis of actual and mental movement times in two graphic tasks

This study compared the temporal organization of graphic movements executed either actually or mentally. Six subjects had to perform two tasks, writing a sentence and drawing a cube, either as a real performance or as an imagined one, with either the right or the left hand, and with either a small or a large tracing amplitude. In the same subject, for the same hand, mental and actual movement times were both very stable and very close from trial to trial regardless of the tracing amplitude. Thus, mental movements mimic closely real movements in their temporal organization and are likely to involve the same planning program.