A VERSATILE EYE-MOVEMENT RECORDER

A small, light eye-movement recorder, capable of registering eye movements from the smallest voluntary movements to movements of 20 degrees of arc, is described. A miniature light projector gives a beam of infrared (or blue) light, which is reflected by the cornea of the eye. The beam is deflected by any movement of the eye. An optical system transforms the motion of the beam into changes of light intensity. These are translated into magnified fluctuations of current in a multiplier phototube. The output is translated into graphic form by an ink-writer fitted with a D.C. amplifier. The apparatus, except for the writer but including a helmet, weighs about 300–500 g and is mounted on the subject's head without appreciably disturbing the field of vision.     

Visual bridgingof empty gaps in the optic flow

This is a study of perception of bending motion and jointed rigid motions over large invisible segments of a bending line. In this project, we investigated the visual perception of changing form of lines, built up by a series of dots and presented under highly reduced pictorial conditions. The changing form was indicated by one or two moving and continuously changing visible fragments of the line. The most extreme condition studied was the perception of the bending of an initially vertical 24-dot line, visually represented only by the stationary base dot and the two moving dots at its top. In this experiment, nearly all subjects reported experiencing a smooth bending connection over the 21-dot empty gap. Three experiments are described and analyzed. The results suggest that the human visual system is astonishingly well adapted for derivation of relevant figurai information from such severely reduced, continuously changing optical presentation. An explanation in terms of automatic sensory mechanisms related to the physiological receptive field effect is proposed.     

CATECHOLAMINE EXCRETION IN YOUNG CHILDREN AND THEIR PARENTS AS RELATED TO BEHAVIOR

L ambert , W. W., J ohansson , G., F rankenhaeuser , M. & K lackenberg -L arsson , I. Catecholamine excretion in young children and their parents as related to behavior. Scand. J. Psychol ., 1969, 10, 306–318. — Catecholamine excretion in 100 children and their parents was examined in relation to the children's behavior and to data on the parents' disciplinary procedures: ( a ) children's adrenaline excretion was positively correlated with their intellectual level, ( b ) their noradrenaline excretion was positively correlated with that of their mothers, as well as with both parents' age at the birth of the child, ( c ) mothers' adrenaline excretion was positively correlated with the frequency at which the fathers punished their children by smacking, and ( d ) fathers' noradrenaline excretion was negatively correlated with their own as well as with their wives' frequency of smacking their children.     

Is the association between childhood maltreatment and aggressive behavior mediated by hostile attribution bias in women? A discordant twin and sibling study

Understanding the mechanisms behind aggressive behavior (AGG) is vital so that effective prevention and intervention strategies can be developed. Maltreated children are hypothesized to be prone to social information processing biases, such as hostile attribution bias (HAB), which, in turn, may increase the likelihood of behaving aggressively. The first aim of the present study was to replicate findings regarding associations between childhood maltreatment (CM), HAB, and aggression in a population‐based sample of Finnish female twins and their sisters (N = 2,167). However, these associations might not be causal but instead confounded by familial factors, shared between the variables. The second aim was, thus, to test the associations when potential confounding by familial (genetic or common environmental) effects were controlled for using a multilevel discordant twin and sibling design within (a) 379 pairs of twins (n_pairs = 239) or siblings (n_pairs = 140), and (b) within the 131 monozygotic (MZ) twin pairs. Consistent with previous studies, HAB mediated the association between CM and AGG when familial confounding was uncontrolled. No support was found for the mediation when controlling for familial confounding. Between‐pair associations were found between CM and AGG, and between CM and HAB. In addition, within‐pair associations were found between HAB and AGG, and between CM and AGG, however, these were nonsignificant in the discordant MZ analysis, offering the most stringent control of familial confounding. The results indicate the necessity of taking familial confounding into account when investigating the development of AGG.     

Housing design and people with severe mental illness: An observational approach to the investigation of supported housing facilities

An observational approach was employed to investigate the role played by architectural characteristics of supported housing facilities (SHF) in sustaining interactional behavior among people with severe mental illness (SMI) (N = 29) and staff (N = 27). The observations were carried out in dining areas, corridors and outdoor environments of SHF (N = 4). In order to test differences in the observed behaviors two SHFs with high physical‐environment quality (HQ) and two with low physical‐environment quality (LQ) according to the perception of people with SMI were chosen. Results showed that the dining areas of HQ better support social interactions between SHF users. No differences between the housing facilities were found concerning corridors areas, while housing facilities that provided proximity and accessibility to outdoor environments, such as those with HQ, were significantly more supportive for social interactional behavior than LQ housing. These results corroborate previous findings from this project and suggest that the characteristics of the housing design have a significant impact on the use of the environment and on the behavior patterns in the setting.     

Surrogate consent to non-beneficial research: erring on the right side when substituted judgments may be inaccurate

Part of the standard protection of decisionally incapacitated research subjects is a prohibition against enrolling them unless surrogate decision makers authorize it. A common view is that surrogates primarily ought to make their decisions based on what the decisionally incapacitated subject would have wanted regarding research participation. However, empirical studies indicate that surrogate predictions about such preferences are not very accurate. The focus of this article is the significance of surrogate accuracy in the context of research that is not expected to benefit the research subject. We identify three morally relevant asymmetries between being enrolled and not being enrolled in such non-beneficial research, and conclude that when there is a non-negligible probability that surrogates’ predictions are wrong, it will generally be better to err on the side of not authorizing enrollment.     

Individual Differences in Early Executive Functions: A Longitudinal Study from 12 to 36 Months

It has been proposed that executive functions develop in a hierarchical fashion, such that early, simple abilities seen already during the first year of life become increasingly coordinated with development, thereby enabling the emergence of more complex abilities. Although this hierarchical model has received support from empirical studies comparing executive function task performance across age groups, necessary support from longitudinal studies taking an individual differences perspective on development is missing. In addition, the model stresses the importance of attention in executive function development, but we do not know in what way attention contributes to the continued development once the earliest forms of simple functions have emerged. Using a longitudinal design, the present study investigated the relations between individual differences in simpler forms of executive functions as well as sustained attention at age 12 months and more complex executive functions at 24 and 36 months. The results indicated partial support for the hierarchical model, with infant inhibition being predictive of working memory in toddlerhood. In addition, at 12 months, sustained attention contributed to the development of toddler executive functions via the simple executive functions. This suggests that by this age, sustained attention has become an integrated part of early, simple executive functions. Copyright © 2015 John Wiley & Sons, Ltd.     

Anticipatory models in gaze control: a developmental model

Infants gradually learn to predict the motion of moving targets and change from a strategy that mainly depends on saccades to one that depends on anticipatory control of smooth pursuit. A model is described that combines three types of mechanisms for gaze control that develops in a way similar to infants. Initially, gaze control is purely reactive, but as the anticipatory models become more accurate, the gain of the pursuit will increase and lead to a larger fraction of smooth eye movements. Finally, a third system learns to predict changes in target motion, which will lead to fast retuning of the parameters in the anticipatory model.     

Do elderly couples have a better prospective memory than other elderly people when they collaborate?

A naturalistic study investigated how memory tasks affected group productivity for two individuals working in three kinds of group constellations: old married couples, old non‐friend pairs, and nominal groups of two individuals working on their own. The retrospective memory task was to recall episodic information given on a visit to a university campus. The prospective memory task was to remind the participants of actions to be performed during the visit. The prospective memory tasks were event‐based or time‐based. The delay or retention interval was also manipulated. In addition, an interview on how the elderly handled remembering during daily life was included. The results suggest that: (1) dyads suffered from collaboration relative to the predicted potential, replicating earlier research; old married couples did not reduce the same productivity loss as clearly as friends did in former studies; the couples who claimed that they used a transactive memory system, however, achieved the same productivity as the nominal pairs (i.e. the predicted potential; (2) the task effects produced unexpected results, some of which could be accounted for by the naturalistic setting used. Copyright © 2000 John Wiley & Sons, Ltd.