For each of the following abstracts, evaluate the internal and external validity of the study (remember, in many studies, the higher one is, the lower the other is). Also identify two or three issues that could threaten the internal validity of the study. 

 

1) There is evidence suggesting that children's play with spatial toys (e.g., puzzles and blocks) correlates with spatial development. Females play less with spatial toys than do males, which arguably accounts for males' spatial advantages; children with high socioeconomic status (SES) also show an advantage, though SES-related differences in spatial play have been less studied than gender-related differences. Using a large, nationally representative sample from the standardization study of the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition, and controlling for other cognitive abilities, we observed a specific relation between parent-reported frequency of spatial play and Block Design scores that was invariant across gender and SES. Reported spatial play was higher for boys than for girls, but controlling for spatial play did not eliminate boys' relative advantage on this subtest. SES groups did not differ in reported frequency of spatial play. Future research should consider quality as well as quantity of play, and should explore underlying mechanisms to evaluate causality. (Jirout & Newcombe, 2015) 

 

2) Although self-rated personality traits predict mortality risk, no study has examined whether one's friends can perceive personality characteristics that predict one's mortality risk. Moreover, it is unclear whether observers' reports (compared with self-reports) provide better or unique information concerning the personal characteristics that result in longer and healthier lives. To test whether friends' reports of personality predict mortality risk, we used data from a 75-year longitudinal study (the Kelly/Connolly Longitudinal Study on Personality and Aging). In that study, 600 participants were observed beginning in 1935 through 1938, when they were in their mid-20s, and continuing through 2013. Male participants seen by their friends as more conscientious and open lived longer, whereas friend-rated emotional stability and agreeableness were protective for women. Friends' ratings were better predictors of longevity than were self-reports of personality, in part because friends' ratings could be aggregated to provide a more reliable assessment. Our findings demonstrate the utility of observers' reports in the study of health and provide insights concerning the pathways by which personality traits influence health. (Jackson, Connolly, Garrison, Leveille, & Connolly, 2015) 

 

3) We showed that anticipatory cognitive control could be unconsciously instantiated through subliminal cues that predicted enhanced future control needs. In task-switching experiments, one of three subliminal cues preceded each trial. Participants had no conscious experience or knowledge of these cues, but their performance was significantly improved on switch trials after cues that predicted task switches (but not particular tasks). This utilization of subliminal information was flexible and adapted to a change in cues predicting task switches and occurred only when switch trials were difficult and effortful. When cues were consciously visible, participants were unable to discern their relevance and could not use them to enhance switch performance. Our results show that unconscious cognition can implicitly use subliminal information in a goal-directed manner for anticipatory control, and they also suggest that subliminal representations may be more conducive to certain forms of associative learning. (Farooqui & Manly, 2015)