Birth order has no effect on intelligence: a reply and extension of previous findings

We address points raised by Zajonc and Sulloway, who reject findings showing that birth order has no effect on intelligence. Many objections to findings of null birth-order results seem to stem from a misunderstanding of the difference between study designs where birth order is confounded with true causal influences on intelligence across families and designs that control for some of these influences. We discuss some of the consequences of not appreciating the nature of this difference. When between-family confounds are controlled using appropriate study designs and techniques such as multilevel modeling, birth order is shown not to influence intelligence. We conclude with an empirical investigation of the replicability and generalizability of this approach.     

Toy-oriented changes in early arm movements II--joint kinematics

Our recent work suggests that infants begin to change their hand and joint kinematics in the presence of a toy months before the onset of purposeful reaching. Moreover, these 'toy-oriented' changes in hand kinematics cluster into Early, Mid and Late phases. The purpose of the present study was to test hypotheses regarding toy-oriented changes in joint kinematics in the same infants. METHODS: Thirteen infants were observed every other week from 8 weeks up to the first week of reaching around 20 weeks. At each session, a high-speed motion analysis system recorded infants' arm movements with and without a toy present. RESULTS: During the Early phase, infants scaled down their movements. In contrast, during the Mid phase infants scaled up their movements and did not change the relationship between the shoulder and elbow for speed and smoothness-related variables. In addition, infants showed toy-oriented changes such as increase in shoulder flexion and adduction. In the Late phase, infants continued to produce toy-oriented changes in shoulder orientation, and increased shoulder excursion and speed relative to the elbow. Thus, the toy-oriented changes in hand kinematics in the Mid and Late phases [Bhat, A. N., & Galloway, J. C. (2006). Toy-oriented changes in early arm movements of young infants: Hand kinematics. Infant Behavior and Development, 29(3), 358-372] more closely followed changes in shoulder kinematics. Lastly, results are discussed in terms of shoulder-elbow dissociations, speed-amplitude relationships, and the key role of spontaneous movements in the development of reaching.     

Moderating Effects of Religious/Spiritual Coping in the Relation Between Perceived Stress and Psychological Well-Being

Although the relationship between stress and depressive symptoms is well documented, less is known about the role of coping strategies, in particular strategies for coping via religious or spiritual means. To investigate the relationships among these factors, data was collected with questionnaires completed by 127 MSW students at a northeastern university in 2003. Significant Stress×Religious/Spiritual Coping buffer interactions were found in the relationship between stress and depression. EQS 6.1 and hierarchical moderated regression analysis showed that religious/spiritual coping reduced the impact of stress on depression. Implications for practice are discussed.     

Reasons to act and believe: naturalism and rational justification in Hume’s philosophical project

Is Hume a naturalist? Does he regard all or nearly all beliefs and actions as rationally unjustified? In order to settle these questions, it is necessary to examine their key terms (‘naturalism’ and ‘rational justification’) and to understand the character—especially the normative character—of Hume’s philosophical project. This paper argues (i) that Hume is a naturalist—and, in particular, both a moral and an epistemic naturalist—in quite robust ways; and (ii) that Hume can properly regard many actions and beliefs as “rationally justified” in several different senses of that term.     

Threat-related attentional bias in anxious and nonanxious individuals: a meta-analytic study

This meta-analysis of 172 studies (N = 2,263 anxious,N = 1,768 nonanxious) examined the boundary conditions of threat-related attentional biases in anxiety. Overall, the results show that the bias is reliably demonstrated with different experimental paradigms and under a variety of experimental conditions, but that it is only an effect size of d = 0.45. Although processes requiring conscious perception of threat contribute to the bias, a significant bias is also observed with stimuli outside awareness. The bias is of comparable magnitude across different types of anxious populations (individuals with different clinical disorders, high-anxious nonclinical individuals, anxious children and adults) and is not observed in nonanxious individuals. Empirical and clinical implications as well as future directions for research are discussed.     

Substance use risk across three generations: the roles of parent discipline practices and inhibitory control.

This study used 3 generations and 21 years of prospective data to test models of intergenerational transmission of substance use and substance use risk. Thus, the study extends prior studies in the field that have focused predominantly on substance abuse. The association between the grandparental generation's (G1 mother and father) and the parental generation's (G2 father) alcohol use and illicit drug use was hypothesized to be mediated by G2's poor inhibitory control. Additionally, G1's poor discipline of G2 was hypothesized to be directly associated with G2's substance use as well as to partially mediate the association between G1's substance use and G2's inhibitory control. In turn, G2's substance use in late adolescence was expected to be associated with its offspring's (G3) poor inhibitory control at age 3 years. Findings partially supported the predictions and varied by substance. For alcohol use, only cross-generational associations in use were found. For illicit drugs, both poor inhibitory control and poor discipline played some mediational role in cross-generational use.     

Neuropsychological findings of extrapontine myelinolysis without central pontine myelinolysis

Central pontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) are well recognized syndromes related to the rapid correction of hyponatremia, which are reported to show brain stem signs and various movement disorders. Cognitive dysfunction and neuropsychological findings, however, have seldom been reported. Cognitive manifestations in osmotic myelinolysis may have been underestimated due to the prominent brain stem symptoms and movement disorders. We report a case of EPM without CPM and describe the neuropsychological findings of EPM. The absence of CPM in this case made it possible to test neuropsychological function in the acute stage. Neuropsychological testing showed severe impairment of attention, verbal and visual memory, visuospatial function, and frontal/executive function. Language and language-related functions were normal except naming.     

Bootstrapping to test for nonzero population correlation coefficients using univariate sampling

This article proposes 2 new approaches to test a nonzero population correlation (rho): the hypothesis-imposed univariate sampling bootstrap (HI) and the observed-imposed univariate sampling bootstrap (OI). The authors simulated correlated populations with various combinations of normal and skewed variates. With alpha set=.05, N> or =10, and rho< or =0.4, empirical Type I error rates of the parametric r and the conventional bivariate sampling bootstrap reached .168 and .081, respectively, whereas the largest error rates of the HI and the OI were .079 and .062. On the basis of these results, the authors suggest that the OI is preferable in alpha control to parametric approaches if the researcher believes the population is nonnormal and wishes to test for nonzero rhos of moderate size.     

Characteristics of Internet use in relation to game genre in Korean adolescents.

As the number of internet users increases, a new game genre using the internet as a networking tool is emerging. Some game genres are regarded as having greater addiction potentials than others. Games and the internet are closely related. We investigated games frequently used by adolescents and classified each of them with the help of game professionals. We also examined internet use patterns to identify relationships between game genre and internet use patterns. 627 middle school and high school students (male 488, female 139) completed questionnaires concerning computer and game use patterns and Korean internet addiction scales. Game genres were divided into eight criteria (simulation, role playing game, web board, community, action, adventure, shooting, and sports). Using Korean internet addiction scales, 627 participants were divided into a normal group (474), a potential risk group (128), and a high-risk group (25). Each group showed significant differences in total internet addiction scores. We classified players into specific game users based upon the game types they most prefer. Role playing game users showed significantly higher internet addiction scores than web board and sports game users. Game and internet addictions are also connected with interpersonal relationship patterns. We suggest that users of some game genre have unique psychological addiction potentials that are different from others and that this influences both game selection and internet use.