Thought Control
Video game practice optimizes executive control skills in dual-task and task switching situations
Tilo Strobach, Peter Frensch & Torsten Schubert
Acta Psychologica, May 2012, Pages 13-24
Abstract:
We examined the relation of action video game practice and the optimization of executive control skills that are needed to coordinate two different tasks. As action video games are similar to real life situations and complex in nature, and include numerous concurrent actions, they may generate an ideal environment for practicing these skills (Green & Bavelier, 2008). For two types of experimental paradigms, dual-task and task switching respectively; we obtained performance advantages for experienced video gamers compared to non-gamers in situations in which two different tasks were processed simultaneously or sequentially. This advantage was absent in single-task situations. These findings indicate optimized executive control skills in video gamers. Similar findings in non-gamers after 15 h of action video game practice when compared to non-gamers with practice on a puzzle game clarified the causal relation between video game practice and the optimization of executive control skills.
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Cranial change in America: 1815 to 1980
Richard Jantz & Lee Jantz
University of Tennessee Working Paper, April 2012
Abstract:
The American population has experienced remarkable change in cranial morphology. Some of these have already been documented, but this paper expands on previous results by increasing the time frame, sample sizes and attempting to identify points in time when change begins, or proceeds most rapidly, which in turn may provide clues to reasons for the changes. Data sets employed are those from the Forensic Anthropology Data Bank, the University of Tennessee Donated collection, the Terry and Todd Anatomical collections, Civil War, and crania from historical cemeteries. All have documented birth and death dates, allowing calculation of birth year. Five standard vault and two face measurements from over 1500 crania were available. The analysis was limited to Americans of European ancestry. Size was defined as the geometric mean of the measurements, treating the vault and face measurements separately. Dividing each of the variables by size created shape variables. Cranial size shows significant increase, but the most marked change occurs in shape. Cranial vaults become higher (basion-bregma), bases become longer (basion-nasion), and bases become narrower (biauricular breadth). Most changes begin occurring mid to late 19th century and continue through the 1980s. There is negative interaction in the shape variables of breadth and those of height and base length. Face changes are less pronounced, but faces become significantly narrower and higher. An explanation of why these changes take place cannot yet be offered, but their timing offers a place to begin the search for correspondence with changes in quality of life.
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The Effect of Breastfeeding on Children's Cognitive and Noncognitive Development
Cristina Borra, Maria Iacovou & Almudena Sevilla
Labour Economics, forthcoming
Abstract:
This paper uses Propensity Score Matching methods to investigate the relationship between breastfeeding and children's cognitive and noncognitive development. We find that breastfeeding for four weeks is positively and statistically significantly associated with higher cognitive test scores, by around one tenth of a standard deviation. The association between breastfeeding and noncognitive development is weaker, and is restricted to children of less educated mothers. We conclude that interventions which increase breastfeeding rates would improve not only children's health, but also their cognitive skills, and possibly also their noncognitive development.
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Intelligence, Birth Order, and Family Size
Satoshi Kanazawa
Personality and Social Psychology Bulletin, forthcoming
Abstract:
The analysis of the National Child Development Study in the United Kingdom (n = 17,419) replicates some earlier findings and shows that genuine within-family data are not necessary to make the apparent birth-order effect on intelligence disappear. Birth order is not associated with intelligence in between-family data once the number of siblings is statistically controlled. The analyses support the admixture hypothesis, which avers that the apparent birth-order effect on intelligence is an artifact of family size, and cast doubt on the confluence and resource dilution models, both of which claim that birth order has a causal influence on children's cognitive development. The analyses suggest that birth order has no genuine causal effect on general intelligence.
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The role of intelligence in the formation of well-being: From job rewards to job satisfaction
Yoav Ganzach & Itzhak Fried
Intelligence, July-August 2012, Pages 333-342
Abstract:
In a longitudinal study, we investigate the moderating role of intelligence on the effects of intrinsic and extrinsic rewards and intrinsic and extrinsic satisfactions on global job satisfaction. The results support our hypotheses that: (1) intrinsic rewards and intrinsic satisfaction are more strongly related to global job satisfaction among individuals who are higher rather than lower in intelligence; and (2) extrinsic rewards and extrinsic satisfaction are more strongly related to global job satisfaction among individuals who are lower rather than higher in intelligence. We also suggest that these effects could be viewed in terms of a moderated mediation model in which facets' satisfaction mediate the effects of rewards on global satisfaction, and intelligence moderates the relationship between facets' satisfaction and global satisfaction. Implications of the results were discussed.
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Electronic Play, Study, Communication, and Adolescent Achievement, 2003-2008
Sandra Hofferth & Ui Jeong Moon
Journal of Research on Adolescence, June 2012, Pages 215-224
Abstract:
Adolescents' time spent messaging, exploring websites, and studying on the computer increased between 2003 and 2008. Using data from the Panel Study of Income Dynamics Child Development Supplement, this study examines how such changes have influenced individual achievement and behavior from childhood to adolescence. Greater communications and Internet web time proved detrimental to vocabulary and reading whereas the increased use of computer games was associated with increased reading and problem-solving scores, particularly for girls and minority children. Increased use of the computer for studying was associated with increased test scores for girls, but not boys. The consequences are more benign than many feared. Groups that have traditionally used the computer less (girls, minority children) appear to benefit from greater use.
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Jason Boardman et al.
Social Science & Medicine, May 2012, Pages 1584-1590
Abstract:
The goal of this paper is to describe the simultaneous influence of social and genetic risk factors on declines in cognitive functioning among older American adults. We use detailed information about the social characteristics of older adults' neighborhoods from the Chicago Health and Aging Project (n = 1655; ages 65+) in conjunction with information about respondent's APOE genotype to predict changes in cognitive function over time. Results indicate that the presence of the ɛ4 allele is associated with a significantly lower cognitive function score at baseline and greater declines in cognitive function compared to those without this risk allele. Importantly, we also show significant variation in the effect of the ɛ4 allele across neighborhoods and our results indicate that this genotype is more strongly associated with cognitive function for residents of neighborhoods with the lowest levels of social disorder. Our findings support the non-causal social push gene-environment interaction model.
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Socioeconomic risk moderates the link between household chaos and maternal executive function
Kirby Deater-Deckard et al.
Journal of Family Psychology, June 2012, Pages 391-399
Abstract:
We examined the link between household chaos (i.e., noise, clutter, disarray, lack of routines) and maternal executive function (i.e., effortful regulation of attention and memory), and whether it varied as a function of socioeconomic risk (i.e., single parenthood, lower mother and father educational attainment, housing situation, and father unemployment). We hypothesized that: 1) higher levels of household chaos would be linked with poorer maternal executive function, even when controlling for other measures of cognitive functioning (e.g., verbal ability), and 2) this link would be strongest in the most socioeconomically distressed or lowest-socioeconomic status households. The diverse sample included 153 mothers from urban and rural areas who completed a questionnaire and a battery of cognitive executive function tasks and a verbal ability task in the laboratory. Results were mixed for Hypothesis 1, and consistent with Hypothesis 2. Two-thirds of the variance overlapped between household chaos and maternal executive function, but only in families with high levels of socioeconomic risk. This pattern was not found for chaos and maternal verbal ability, suggesting that the potentially deleterious effects of household chaos may be specific to maternal executive function. The findings implicate household chaos as a powerful statistical predictor of maternal executive function in socioeconomically distressed contexts.
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Katrin Bruchmüller, Jürgen Margraf & Silvia Schneider
Journal of Consulting and Clinical Psychology, February 2012, Pages 128-138
Objective: Unresolved questions exist concerning diagnosis of ADHD. First, some studies suggest a potential overdiagnosis. Second, compared with the male-female ratio in the general population (3:1), many more boys receive ADHD treatment compared with girls (6-9:1). We hypothesized that this occurs because therapists do not adhere to Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) and International Classification of Diseases (10th rev.; ICD-10) criteria. Instead, we hypothesized that, in accordance with the representativeness heuristic, therapists might diagnose attention-deficit/hyperactivity disorder (ADHD) if a patient resembles their concept of a prototypical ADHD child, leading therapists to overlook certain exclusion criteria. This may result in overdiagnosis. Furthermore, as ADHD is more frequent in males, a boy might be seen as a more prototypical ADHD child and might therefore receive an ADHD diagnosis more readily than a girl would.
Method: We sent a case vignette to 1,000 child psychologists, psychiatrists, and social workers and asked them to give a diagnosis. Four versions of the vignette existed: Vignette 1 (ADHD) fulfilled all DSM-IV/ICD-10 criteria of ADHD. Vignettes 2-4 (non-ADHD) included several ADHD symptoms but stated other ADHD criteria were nonfulfilled. Therefore, an ADHD diagnosis could not be given. Furthermore, boy and girl versions of each vignette were created.
Results: In Vignettes 2-4 (non-ADHD), 16.7% of therapists diagnosed ADHD. In the boy version of these vignettes, therapists diagnosed ADHD around 2 times more than they did with the girl vignettes.
Conclusions: Therapists do not adhere strictly to diagnostic manuals. Our study suggests that overdiagnosis of ADHD occurs in clinical routine and that the patient's gender influences diagnosis considerably. Thorough diagnostic training might help therapists to avoid these biases.
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Liked Music Increases Spatial Rotation Performance Regardless of Tempo
Nick Perham & Tom Withey
Current Psychology, June 2012, Pages 168-181
Abstract:
Performance on spatial rotation tasks has been shown to improve following listening to music that one likes with the explanation that the fast tempo, and the major mode associated with it, increases arousal and mood. However, given that research also shows that people sometimes like slow-tempo music as much as fast-tempo music it seems remiss that this preference effect has not been explored for slow-tempo music. We extend previous findings by using a more ecologically-valid method and explore whether the tempo effect was independent of the preference for the music, especially when the music is of a slow tempo. Participants listened to both liked and disliked music, in either a fast or slow tempo, prior to completing a series of spatial rotation tasks. In both tempos, liked music was associated with significantly better spatial rotation performance than disliked music. Interestingly, disliked, fast-tempo music was no better than liked, slow-tempo music. Results are discussed with respect to the arousal and mood literature.
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Karri Silventoinen et al.
Behavior Genetics, May 2012, Pages 393-401
Abstract:
Associations of height and head circumference with IQ are well documented, but much less is known about the association of IQ with other anthropometric measures or the mechanisms behind these associations. We therefore analyzed the associations between IQ and several anthropometric measures using a twin-study design. Twins born in Minnesota were assessed at either age 11 (756 complete pairs) or 17 (626 complete pairs) and analyzed using genetic modeling. Head circumference and height showed the most consistent positive associations with IQ, whereas more detailed anthropometric measures were not significantly better predictors of IQ. These associations were mainly due to common genetic factors. Our results suggest that the same genetic factors have an effect on physical and cognitive development. Head circumference and height capture information on children's physical development, which is partly associated also with cognitive development.
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Breastfeeding predicts handedness
Kevin Denny
Laterality: Asymmetries of Body, Brain and Cognition, May/June 2012, Pages 361-368
Abstract:
This study examined whether being breastfed predicts handedness. Two large representative samples from Britain (n=13,421) and Ireland (n=8,426) were used. Multivariate probit models are estimated, reporting the marginal effects of covariates on the probability of a child being right-handed. For both datasets, children who have been breastfed for a minimum period (between 1 month and 6 weeks) are significantly less likely to be left-handed. The results are robust to a variety of controls. Hence breastfeeding is an environmental factor that predicts handedness in a non-linear way, although the mechanism is unknown.
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Cumulative estrogen exposure and prospective memory in older women
Jacqueline Hesson
Brain and Cognition, October 2012, Pages 89-95
Abstract:
This study looked at cumulative lifetime estrogen exposure, as estimated with a mathematical index (Index of Cumulative Estrogen Exposure (ICEE)) that included variables (length of time on estrogen therapy, age at menarche and menopause, postmenopausal body mass index, time since menopause, nulliparity and duration of breastfeeding) known to influence estrogen levels across the life span, and performance on prospective and retrospective memory measures in a group of 50 postmenopausal women (mean age = 69.3 years) who, if they were current or former users of estrogen therapy, had started therapy within 5 years of menopause. The ICEE was found to be a significant predictor of performance on the Prospective Memory task (F(1) = 4.21, p = .046, ). No significant relationship was noted between the ICEE and performance on measures of retrospective memory. The results suggest that the level of cumulative lifetime exposure to estrogen a woman has influences her prospective memory performance later in life and that the influence of reproductive and biological markers of endogenous estrogen exposure are relevant factors to consider when studying the effect of estrogen therapy on cognitive functioning in postmenopausal women. In addition, the finding that performance on a measure of prospective memory, but not performance on measures of retrospective memory, was associated with the ICEE adds further support to the theory that the frontal cortex may be especially sensitive to estrogen.
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Extracting Dynamical Equations from Experimental Data is NP Hard
Toby Cubitt1, Jens Eisert & Michael Wolf
Physical Review Letters, March 2012
Abstract:
The behavior of any physical system is governed by its underlying dynamical equations. Much of physics is concerned with discovering these dynamical equations and understanding their consequences. In this Letter, we show that, remarkably, identifying the underlying dynamical equation from any amount of experimental data, however precise, is a provably computationally hard problem (it is NP hard), both for classical and quantum mechanical systems. As a by-product of this work, we give complexity-theoretic answers to both the quantum and classical embedding problems, two long-standing open problems in mathematics (the classical problem, in particular, dating back over 70 years).
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Michael Ford & Bryan Wiggins
Journal of Occupational Health Psychology, forthcoming
Abstract:
Interactions between occupational-level physical hazards and cognitive ability and skill requirements were examined as predictors of injury incidence rates as reported by the U. S. Bureau of Labor Statistics. Based on ratings provided in the Occupational Information Network (O∗NET) database, results across 563 occupations indicate that physical hazards at the occupational level were strongly related to injury incidence rates. Also, as expected, the physical hazard-injury rate relationship was stronger among occupations with high cognitive ability and skill requirements. In addition, there was an unexpected main effect such that occupations with high cognitive ability and skill requirements had lower injury rates even after controlling for physical hazards. The main effect of cognitive ability and skill requirements, combined with the interaction with physical hazards, resulted in unexpectedly high injury rates for low-ability and low-skill occupations with low physical hazard levels. Substantive and methodological explanations for these interactions and their theoretical and practical implications are offered. Results suggest that organizations and occupational health and safety researchers and practitioners should consider the occupational level of analysis and interactions between physical hazards and cognitive requirements in future research and practice when attempting to understand and prevent injuries.
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Beliefs and endogenous cognitive levels: An experimental study
Marina Agranov et al.
Games and Economic Behavior, July 2012, Pages 449-463
Abstract:
In this paper we use a laboratory setting to manipulate our subjectsʼ beliefs about the cognitive levels of the players they are playing against. We show that in the context of the 2/3 guessing game, individual choices crucially depend on their beliefs about the level of others. Hence, a subjectʼs true cognitive level may be different than the one he exhibits in a game with the difference being attributed to his expectations about the sophistication of the players he is playing against.
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The Impact of Social Disparity on Prefrontal Function in Childhood
Margaret Sheridan et al.
PLoS ONE, April 2012
Abstract:
The prefrontal cortex (PFC) develops from birth through late adolescence. This extended developmental trajectory provides many opportunities for experience to shape the structure and function of the PFC. To date, a few studies have reported links between parental socioeconomic status (SES) and prefrontal function in childhood, raising the possibility that aspects of environment associated with SES impact prefrontal function. Considering that behavioral measures of prefrontal function are associated with learning across multiple domains, this is an important area of investigation. In this study, we used fMRI to replicate previous findings, demonstrating an association between parental SES and PFC function during childhood. In addition, we present two hypothetical mechanisms by which SES could come to affect PFC function of this association: language environment and stress reactivity. We measured language use in the home environment and change in salivary cortisol before and after fMRI scanning. Complexity of family language, but not the child's own language use, was associated with both parental SES and PFC activation. Change in salivary cortisol was also associated with both SES and PFC activation. These observed associations emphasize the importance of both enrichment and adversity-reduction interventions in creating good developmental environments for all children.
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Haplogroups as evolutionary markers of cognitive ability
Heiner Rindermann, Michael Woodley & James Stratford
Intelligence, July-August 2012, Pages 362-375
Abstract:
Studies investigating evolutionary theories on the origins of national differences in intelligence have been criticized on the basis that both national cognitive ability measures and supposedly evolutionarily informative proxies (such as latitude and climate) are confounded with general developmental status. In this study 14 Y chromosomal haplogroups (N = 47 countries) are employed as evolutionary markers. These are (most probably) not intelligence coding genes, but proxies of evolutionary development with potential relevance to cognitive ability. Correlations and regression analyses with a general developmental indicator (HDI) revealed that seven haplogroups were empirically important predictors of national cognitive ability (I, R1a, R1b, N, J1, E, T[+L]). Based on their evolutionary meaning and correlation with cognitive ability these haplogroups were grouped into two sets. Combined, they accounted in a regression and path analyses for 32-51% of the variance in national intelligence relative to the developmental indicator (35-58%). This pattern was replicated internationally with further controls (e.g. latitude, spatial autocorrelation etc.) and at the regional level in two independent samples (within Italy and Spain). These findings, using a conservative estimate of evolutionary influences, provide support for a mixed influence on national cognitive ability stemming from both current environmental and past environmental (evolutionary) factors.