Self-reported arousal Factorial complexity as a function of the subject's arousal level

Abstract.— The factorial stability of a previously constructed six-factor check-list for self-reported arousal was studied in three different situations which were conceived of as inducing different levels of arousal, viz. in the evening before going to bed, at a lecture, and at an examination. The analyses showed that the six factors obtained in the Lecture group were reduced to five in the Examination group and to four in the Evening group. This reduction was due to a combination of the items from pairs of the original factors into one factor. Significant differences between the three groups were obtained in all factors but one. The results were regarded as support for the usefulness of the six-factor instrument, the implication being that one or two of the factors in some situations might be redundant. The relevance of the results for a previously proposed model of arousal was discussed.     

Chromatic induction as a function of luminance relations

Chromatic induction by red, green, and blue surround was studied as a function of surround/test field luminance ratio using a compensation method. Luminance ratios from 0.01 to 28.7 were used. The number of subjects was 8–10 in the three experiments. The results show maximum induction to appear at a luminance ratio around 1.0 when varying the test field luminance (Experiment 1) and at higher ratios when varying the surrounding luminance (Experiments 2 and 3). This difference is discussed in relation to the Kirschmann-Kinney controversy (Kirschmann, 1890; Kinney, 1962) and in relation to an earlier study using a magnitude estimation method (Bergström & Derefeldt, 1975).     

Effects of surround/test field luminance ratio on induced colour

Abstract.— According to Kirschmann's third law the induced colour is at its maximum when the inducing and induced fields are of equal luminance. Later studies (Kinney, 1962) show the induced colour to be most pronounced at a luminance ratio (inducing/induced) of about 4/1. In the present study the amount of colour induced into an achromatic test field was determined for one inducing colour, red, by letting observers judge the colour strength of the induced field. The test (or induced) field luminance was varied to give luminance ratios between 0.5/1 and 2/1. The results show that both colour strength and blackness increase as the luminance ratio is increased. The fact that the test field was judged even to have maximum chromatic colour strength and maximum blackness at the same time is discussed in relation to the method used and in relation to earlier studies on the "mode of appearance" of colours and the bidimensionality of achromatic colours.     

Self-reported arousal during sleep deprivation and its relation to performance and physiological variables

Bohlin, G. & Kjellberg, A. Self-reported arousal during sleep deprivation and its relation to performance and physiological variables. Scand. J. Psychol., 1973, 14, 78–86.-Thayer's (1967) self-report inventory was translated and subjected to factor analysis. A four factor solution, slightly deviant from Thayer's, was adopted. The factors were labelled Sleep-Wakefulness, Stress, Euphoria, and Energy. Twenty Ss took part in a sleep deprivation (SD) experiment, which included physiological (EEG, skin conductance, body temperature), and reaction time (RT) recordings. All four factors showed decreasing trends over the night of SD, and with the exception of the Stres Factor, they were correlated with body temperature variations. The ratings in Sleep-Wakefulness and Energy were significantly lowered as a result of SD. The effect of SD upon these factors was also correlated with the effect upon the RT task and the physiological variables. From these results a model for phenomenological arousal was proposed and discussed.     

Socio‐emotional development: From infancy to young adulthood

Results from the Uppsala Longitudinal Study (ULS), which started in 1985, are reported in two sections. The first section gives a summary of longitudinal data from infancy to middle childhood (age 9 years; n = 96) concerning predictions of social functioning aspects from the theoretical perspectives of temperament, attachment, and health psychology (social factors). The second section presents the first results emanating from a follow‐up when participants were 21 years old (n = 85). The developmental roots of social anxiety symptoms were studied from the same perspectives as above, although with a special focus on the predictive power of the temperament trait of shyness/inhibition. Results for middle childhood outcomes showed that temperament characteristics were relevant for most outcomes, whereas the contribution of attachment was most convincingly shown in relation to social competence and personality. Social factors were found to have moderating functions, but direct effects were also shown, the most interesting perhaps being positive effects of non‐parental day care. Results from the 21‐year data confirmed the expected predictive relation from shyness/inhibition to symptoms of social anxiety and further showed this relation to be specific; the relation to symptoms of depression did not survive control for social anxiety, although the opposite was true. The broad analysis of predictor associations with social anxiety, showing the relevance of other temperament factors as well as interactive effects, again attested to the need for multi‐faceted models to analyze developmental trajectories.     

Prevalence of problematic behaviors in four-year-olds

Prevalence rates for specific behaviors in the Problem Behavior Questionnaire (PBQ; Behar & Stringfield, 1974) and for four psychosomatically related behaviors (soiling, day and night wetting, and complaints about bodily aches) were estimated in a sample of 377 Swedish 4-year-olds described by their parents (mainly mothers). The results showed that several of the behaviors classified as outgoing conduct problems were common in this age group; boys showed more problematic behaviors than girls, as did children with older siblings. Firstborn children with younger siblings were more fearful and worried. No systematic differences between children in different types of day care were found. Maternal education had no relationship to reported child behaviors. The findings were discussed in terms of the four-year-age period as a period of transition and with regard to different family situations.     

Self-reported arousal: further development of a multi-factorial inventory

Abstract.— The previously presented (Bohlin & Kjellberg, 1973) inventory of self-reported arousal, which contained four factor analytically derived scales, was further developed in the following way. First, the original factor pattern was cross-validated. Second, a new response scale was constructed which proved to be superior to the old one. Third, the inventory was extended with new items and factor analysis applied to this new inventory. From the model of phenomenological arousal advanced by Bohlin & Kjellberg (1973) six factors were hypothesized and it was shown that a similar solution could be obtained with the extended inventory. Finally, this six-factor pattern was cross-validated and six scales, labelled Sleep-Wakeful-ness, Energy, Stress, Irritation, Euphoria, and Concentration, were constructed.     

Hue shift of induced colour as a function of luminance relations

The hue of induced colour was studied as a function of surround/test field luminance ratio using a chromatic surround and an achromatic central test field. The hue of the test field was determined by means of colour naming methods. Three inducing colours were used: blue (Wr No. 47), green (Wr No. 58), and red (Wr No. 25). The number of subjects was 9–11 in the two experiments. The luminance ratio (ranging from 0.07 to 17.1) was varied by varying the luminance of the test field (Experiment 1) or of the surround (Experiment 2). For the blue surround the results show a hue shift in accordance with the Bezold-Brücke phenomenon. For the inducing colours green and red the induced colours are weak, and the hue shifts are more or less unsystematic though there are individual subjects showing a trend in the Bezold-Brücke direction. It is concluded that the hue shifts depend on the luminance relations rather than on the test field luminance.     

The development of risk acceptance and moral valuation

The relationship between acceptability of risks and moral valuation of risky activities was investigated in children, 10–16 years old. It was found that all age groups exhibited a strong correlation between the two dimensions of risky activities. Older children were more tolerant of risk taking than younger children. Individual actions were judged in a more lenient manner than collective actions. Girls tended to be more morally condemning towards risk taking, but the youngest girls were not less prone to accept risks than boys. General measures of moral development according to Piaget and Kohlberg were not associated with perceived acceptability of risk or the judged morality of risky activities but relations were found between risk taking and assertiveness and perceived freedom, which were the most important factors in accounting for risk and morality attitudes.