Formal and informal classroom settings: Effects on hyperactivity

The behavior of hyperactive children was compared to controls in two different classroom settings. One setting (Informal) involved choice and variety of tasks; the other setting (Formal) involved teacher specification of a small number of tasks. As assessed by a composite observational measure of hyperactivity, there were significant differences between the hyperactive and control groups in the Formal but not in the Informal setting. Analyses of five individual categories of hyperactive behavior showed that, with one exception, the hyperactive group tended to display higher frequencies of behavior than did controls in both settings. For two of the categories, the difference between the groups was significantly larger in the Formal than in the Informal setting. Finally, a modified observational code was suggested that differentiated hyperactives from controls equally in the two settings.     

A low-cost research-oriented biofeedback thermometer with digital readout

The construction of a research-oriented biofeedback thermometer with digital readout is described. The device uses recently developed low-cost integrated circuits and has a liquid crystal readout with capability of .1° and .01°F display. Internal calibration circuitry enables precision monitoring of overall performance stability. The basic thermometer design has potential application as a general instrument for behavioral and physiological research.     

The structure of infant intelligence: An historical overview

An historical overview of investigations that were concerned with delineating the structure and composition of infant intellectual activity is presented. The events which both preceded and culminated in the conceptualization of infant intelligence as a unitary trait, or factor, are traced. Thereafter, recent studies are reviewed which have guided contemporary investigators to contend that infant intellectual activity is comprised of varied sets of relatively independent abilities and factors. Several conclusions are made concerning the points of view which various investigators have held regarding the structure of infant intelligence.     

Behavioral hyperreactivity in the spontaneously hypertensive rat compared to its normotensive progenitor

The spontaneously hypertensive rat (SHR) is an excellent model of essential hypertensive disease. Hyperreactivity has been postulated as a contributing factor in the development of high blood pressure in the SHR and in man. In the maturing organism recurring hypertensive stress responses may promote permanent vascular changes and result in a fixed hypertension. Simple behavioral activity and emotionality rating scales were used to compare a large number of SHR with equally large groups of closely-related and distantly-related normotensive rats. As predicted, the SHR were clearly more active and emotional than their ancestral Wistar Kyoto (WKY) strain. However, the distantly-related normotensive Wistars did not differ from the SHR in either activity or emotionality. These results indicate that behavior and hypertension are not necessarily related in the rat. Nonetheless, the behavioral differences between the SHR and their closest genetic match, the WKY, suggest that arousal and blood pressure levels may be causally linked in this case of naturally occurring hypertension.     

The approximation of one matrix by another of lower rank

The mathematical problem of approximating one matrix by another of lower rank is closely related to the fundamental postulate of factor-theory. When formulated as a least-squares problem, the normal equations cannot be immediately written down, since the elements of the approximate matrix are not independent of one another. The solution of the problem is simplified by first expressing the matrices in a canonic form. It is found that the problem always has a solution which is usually unique. Several conclusions can be drawn from the form of this solution.A hypothetical interpretation of the canonic components of a score matrix is discussed.     

Sex differences in tactual-kinaesthetic and visual perception of vertically

Previous studies on visual and tactual-kinaesthetic perception with head tilted sidewise have shown that the greater deviations are to the left, i.e. the adjustments of a luminous line or a pivoting rod tend to fall counter-clockwise to the perpendicular. This paper shows significant sex difference in tactual-kinaesthetic perception only. Men and women show similar and small deviations to the right with head tilted to the left but, with head tilted to the right, women show clearly greater deviations to the left. The discussion of the visual perception of verticality (the so-called Aubert phenomenon) has been confusing. Our results in the visual experiments show small deviations, and they support Aubert's statement.