Social learning and innovation are positively correlated in pigeons (<Emphasis Type="Italic">Columba livia</Emphasis>)

When animals show both frequent innovation and fast social learning, new behaviours can spread more rapidly through populations and potentially increase rates of natural selection and speciation, as proposed by A.C. Wilson in his behavioural drive hypothesis. Comparative work on primates suggests that more innovative species also show more social learning. In this study, we look at intra-specific variation in innovation and social learning in captive wild-caught pigeons. Performances on an innovative problem-solving task and a social learning task are positively correlated in 42 individuals. The correlation remains significant when the effects of neophobia on the two abilities are removed. Neither sex nor dominance rank are associated with performance on the two tasks. Free-flying flocks of urban pigeons are able to solve the innovative food-finding problem used on captive birds, demonstrating it is within the range of their natural capacities. Taken together with the comparative literature, the positive correlation between innovation and social learning suggests that the two abilities are not traded-off.     

Visual search in children and adults: top-down and bottom-up mechanisms

Three experiments investigated visual search for targets that differed from distractors in colour, size, or orientation. In one condition the target was defined by a conjunction of these features, while in the other condition the target was the odd one out. In all experiments, 6-7- and 9-10-year-old children were compared with young adults. Experiment 1 showed that children's search differed from adults' search in two ways. In conjunction searches children searched more slowly and took longer to reject trials when no target was present. In the odd-one-out experiments, 6-7-year-old children were slower to respond to size targets than to orientation targets, and slower for orientation targets than for colour targets. Both the other groups showed no difference in their rate of responding to colour and orientation. Experiments 2 and 3 highlighted that these results were not a function of either differential density across set sizes (Experiment 2) or discriminability of orientation and colour (Experiment 3). Across all three experiments, the results of both conjunction and odd-one-out searches highlighted a development in visual search from middle to late childhood.     

Examining Subtypes of Behavior Problems Among 3-Year-Old Children,Part III: Investigating Differences in Parenting Practices and Parenting Stress

This study examined parenting of mothers and fathers of 3-year-old children who were classified as hyperactive (HYP), hyperactive and oppositional defiant (HYP/OD), and non-problem based on mothers' reports of behavior. Parents of children with HYP/OD were less warm, showed more negative affect, and more laxness than parents of non-problem children; however, contrary to prediction, they did not differ significantly from parents of children in the HYP group. Compared to mothers of non-problem children, mothers of children in the HYP/OD group reported significantly more parenting stress across all domains, whereas mothers of children in the HYP group only reported elevated levels of stress associated with having a difficult child. Theoretical and treatment implications are discussed.     

Examining Subtypes of Behavior Problems Among 3-Year-Old Children,Part I: Investigating Validity of Subtypes and Biological Risk-Factors

This study examined 3-year-old children who were classified as hyperactive (HYP), oppositional-defiant (OD), hyperactive and oppositional defiant (HYP/OD), and non-problem based on mothers' reports of behavior. Using fathers,' teachers,' and observers' ratings of children's behavior, concurrent validity was excellent for the HYP/OD group, moderate for the HYP group, and poor for the OD group. As predicted, both the HYP/OD and HYP groups reported more prenatal/perinatal birth complications and a greater family history of hyperactivity than did non-problem children. Furthermore, the HYP/OD group showed a greater family history of conduct disorder and oppositional defiant disorder (ODD) symptoms than did non-problem children; however, the HYP group also showed a greater family history of ODD than did non-problem children. Results suggest that as early as age 3, these behavior subtypes appear to be linked to biologically-based risk-factors in ways that are consistent with theories of the development of ADHD.     

Numerical estimation in blind subjects: evidence of the impact of blindness and its following experience

Vision was for a long time considered to be essential in the elaboration of the semantic numerical representation. However, early visual deprivation does not seem to preclude the development of a spatial continuum oriented from left to right to represent numbers (J. Castronovo & X. Seron, 2007; D. Szücs & V. Csépe, 2005). The authors investigated the impact of blindness and its following experience on a 3rd property of the mental number line: its obedience to Weber's law. A group of blind subjects and a group of sighted subjects were submitted to 2 numerical estimation tasks: (a) a keypress estimation task and (b) an auditory events estimation task. Blind and sighted subjects' performance obeyed Weber's law. However, blind subjects demonstrated better numerical estimation abilities than did sighted subjects, especially in contexts involving proprioception, indicating the existence of better mapping abilities between the symbolic representations of numbers and their corresponding magnitude representations, obeying Weber's law (e.g., J. S. Lipton & E. Spelke, 2005). These findings suggest that blindness and its following experience with numbers might result in better accuracy in numerical processing.     

Developmental sources of implicit attitudes

Explanations for implicit and explicit attitude dissociation have largely focused on causes of explicit attitudes. By contrast, this article examines developmental experiences as potential sources of implicit (more than explicit) attitudes, using attitudes toward smoking and body weight, which have shown dissociation with self-reports. In Study 1, smokers' implicit and explicit attitudes toward smoking were uniquely predicted by their early and recent experiences with smoking, respectively. In Study 2, participants' childhood and current weight uniquely predicted implicit and explicit body weight attitudes, respectively. Furthermore, being raised primarily by a beloved, heavyweight mother predicted proheavy implicit (but not explicit) attitudes. In Study 3, people's reports of pleasant dreams in childhood (but not currently) predicted their implicit attitudes toward dreams. In concert, results provide support for theorizing that implicit and explicit attitudes may stem from different sources of information and are, therefore, conceptually distinct.     

The Delay Hypothesis: The Manifestation of Media Effects Over Time

A between‐participants experiment (N = 147) tested for the presence of a delayed effect following exposure to an episode of a legal drama that contained false information. Participants were more likely to endorse false beliefs if they were queried two weeks after watching the program rather than immediately following exposure. The relationship between time and false belief endorsement was found to be moderated by perceived reality of the program. Consistent with the delay hypothesis, those who perceived the legal drama to be unrealistic following exposure had significantly higher false belief scores at Time 2.     

Spontaneous startle activity in newborn infants

Spontaneous startles have been reported to occur most frequently in quiet sleep, less frequently in active sleep and drowse, and relatively nonexistent in the waking states. These findings may be a result of a focus on infants whose prenatal histories reflect a restricted range of the conditions to which normal newborns are exposed. The present study examined the spontaneous startle behavior of 30 newborn infants characterized by high numbers of obstetric complications and by indicators of prenatal malnutrition, but within the range of normal, healthy newborns. In this sample, startles were not limited to the sleep and drowse states. Because individual differences in a number of neonatal behaviors have been related to autonomic nervous system (ANS) functioning, the different pattern of spontaneous startles observed in this sample may be related to the functional integrity of this system.     

Crossnational deviance in the workplace: Diverging impact of organizational commitment in Canada and Belgium

Using a self-report questionnaire from the aggressor's point of view, this study contrasted employees' frustration, perception of procedural justice, organizational commitment, and their relationships to interpersonal deviance in Canada and Belgium. Significant main effects were found in both countries for frustration and procedural justice on psychological and physical violence. Moreover, hierarchical regression analyses revealed significant interactions of country by normative and continuance commitment in interpersonal deviance, indicating the unique patterns relationships in Canada and Belgium. Hofstede's model of cultural dimensions was used to discuss the results.     

Long-Term stress reactions in new immigrants to israel exposed to the chernobyl accident

Abstract

This comparison study examined the relation between presumed level of exposure to the accident at Chernobyl in 1986 to symptoms of post-traumatic stress disorder (PTSD) and other psychological symptoms (depression, somatization, anxiety, obsessive-compulsive style and interpersonal sensitivity), life events and the negative appraisal of the events surrounding the accident. The sample (N = 708) included new immigrants from the former Soviet Union (Confederation of Independent States) who arrived in Israel since 1989 from more exposed areas (n = 137), less exposed (n = 240) and a comparison sample (n = 331) who immigrated from other republics. The exposed groups had higher mean scores on all psychological outcome measures than the comparison group, particularly symptoms of PTSD. Both subsequent stressful life events and a negative, cognitive assessment of events contributed to present psychological distress, independent of exposure.