The impact of sleep deprivation on decision making: a review

Few sleep deprivation (SD) studies involve realism or high-level decision making, factors relevant to managers, military commanders, and so forth, who are undergoing prolonged work during crises. Instead, research has favored simple tasks sensitive to SD mostly because of their dull monotony. In contrast, complex rule-based, convergent, and logical tasks are unaffected by short-term SD, seemingly because of heightened participant interest and compensatory effort. However, recent findings show that despite this effort, SD still impairs decision making involving the unexpected, innovation, revising plans, competing distraction, and effective communication. Decision-making models developed outside SD provide useful perspectives on these latter effects, as does a neuropsychological explanation of sleep function. SD presents particular difficulties for sleep-deprived decision makers who require these latter skills during emergency situations.     

Do you remember proposing marriage to the Pepsi machine? False recollections from a campus walk

During a campus walk, participants were given familiar or bizarre action statements (e.g., “Check the Pepsi machine for change” vs. “Propose marriage to the Pepsi machine”) with instructions either to perform the actions or imagine performing the actions (Group 1) or to watch the experimenter perform the actions or imagine the experimenter performing the actions (Group 2). One day later, some actions were repeated, along with new actions, on a second walk. Two weeks later, the participants took a recognition test for actions presented during the first walk, and they specified whether a recognized action was imagined or performed. Imagining themselves or the experimenter performing familiar or bizarre actions just once led to false recollections of performance for both types of actions. This study extends previous research on imagination inflation by demonstrating that these false performance recollections can occur in a natural, real-life setting following just one imagining.     

Memory for targets in a multilevel simulated environment: Evidence for vertical asymmetry in spatial memory

In two experiments, adult participants explored a symmetrical three-tiered computer-simulated building that contained six distinctive objects, two on each floor. Following exploration, the objects were removed, and the participants were asked to make direction judgments from each floor, indicating the former positions of the objects on that floor and on higher and lower floors. Relative tilt error scores indicated a bias, in that targets that were higher than the test location were judged as consistently lower than their actual positions and targets that were lower than the test location were judged as consistently higher than their actual positions. Absolute tilt errors revealed an asymmetry, with more accurate and less variable tilt errors for judgments directed to lower floors than for judgments directed to higher floors. Experiment 3 ruled out an account of the findings that does not relate them to spatial memory. The results suggest that the superiority of downward over upward spatial judgments, previously reported in two-dimensional visual-spatial tasks, extends to navigational spatial memory.     

Social and psychiatric influences on urban-rural differentials in Australian suicide

The purpose of this study was to investigate urban-rural differentials in Australian suicide rates, and to examine influences that previously have remained largely speculative. Suicide rates for males (all ages and young adults) were significantly higher in rural areas compared to urban areas. Urban-rural suicide rate differences in males were rendered nonsignificant after adjustment for migrant and area socioeconomic status. Adjusting for mental disorder prevalence, in addition to migrant status, reduced the excess suicide risk in rural areas; the excess was reduced further with addition of mental health service utilization. The implications of this study are that socioeconomic circumstances in rural populations contribute to higher male suicide rates compared to urban areas, but these conditions may be partly mediated by mental disorder prevalence and mental health service utilization.     

A functional analytic approach to computer-interactive mathematics

Following a pretest, 11 participants who were naive with regard to various algebraic and trigonometric transformations received an introductory lecture regarding the fundamentals of the rectangular coordinate system. Following the lecture, they took part in a computer-interactive matching-to-sample procedure in which they received training on particular formula-to-formula and formula-to-graph relations as these formulas pertain to reflections and vertical and horizontal shifts. In training A-B, standard formulas served as samples and factored formulas served as comparisons. In training B-C, factored formulas served as samples and graphs served as comparisons. Subsequently, the program assessed for mutually entailed B-A and C-B relations as well as combinatorially entailed C-A and A-C relations. After all participants demonstrated mutual entailment and combinatorial entailment, we employed a test of novel relations to assess 40 different and complex variations of the original training formulas and their respective graphs. Six of 10 participants who completed training demonstrated perfect or near-perfect performance in identifying novel formula-to-graph relations. Three of the 4 participants who made more than three incorrect responses during the assessment of novel relations showed some commonality among their error patterns. Derived transfer of stimulus control using mathematical relations is discussed.     

Nursing and psychological treatments

Presents a comment on "Psychological Treatments" by D. H. Barlow. In his article, Barlow pointed to the need "to solidify the identification of psychology as a health care profession" by changing the terminology of practice in the health care context from psychotherapy to psychological treatments and suggested that the only persons qualified to carry out such interventions are doctoral-level psychologists. Unfortunately, there was no discussion of the health care professionals who already provide psychological treatments in health care settings and their contribution to the evidence base supporting such treatment. The authors find several aspects of the article to be problematic. Overall, the authors feel that suggesting that psychology should claim treatment of psychological disorders and psychological components of physical disorders in health care settings as exclusively its own domain ignores the research and clinical contributions of others.     

The Role of Reproductive Strategies in Academic Attainment

Since there is a tradeoff between prolongedformal education and early reproduction, education canbe construed as a long-term reproductive tactic. Thisreproductive strategies approach was tested by looking at relationships between sociosexuality (SOI)and parental investment (parental income, number ofsiblings, parental divorce, number of step siblings,birth intervals, birth order, closeness to parents) and GPA of 139 White students at a privatecollege. Parental investment was reduced to threefactors (Family Composition, Family Security, andMarital Instability), the last of which was negativelycorrelated with GPA and positively correlated with SOI.SOI was a much stronger (negative) predictor of GPA inwomen, but not men, than ACT was. Results support thereproductive strategies approach and imply that prediction of academic difficulty (and genderdifferences therein) must confront reproductiveissues.     

Sequential analysis of visual habituation in preschool children

The study breaks down the data from a preschool (mean age of students, 63 months) visual habituation experiment using a second-by-second analysis of the entire process, including fixation time and onsets for habituation and recovery trials and for each intertrial interval. The results parallel those suggested by Cohen, DeLoach, and Rissman (Child Development, 1975, 46, 611–617), for infants and are described using a two-process model of visual attention.     

Relations between nutrition and cognitive performance in Egyptian toddlers

Two relatively unexplored questions--which specific components of chronic mild child malnutrition are associated with specific behavioral and cognitive deficits and do psychosocial child rearing factors moderate the nutrition-development relationship?--were investigated in a longitudinal study involving 153 toddlers from the Egyptian village of Kalama. Beginning at study entry at age 18 months and continuing until 30 months, food intake information was obtained for 2 consecutive days each month. During the same period, researchers visited the homes twice a month to observe both toddler behavior and caregiver styles. Finally, standardized infant development tests were administered at 24 months and 30 minutes and the capacity for exploratory, symbolic play was assessed. Specific components of nutritional intake at 18-23 months of age were confirmed to be uniquely related to specific developmental outcomes at 24 months of age. Changes in toddler intake from 18-30 months also predicted 30-month cognitive performance. At 24 months, general mental competence was associated positively with fat intake, total kilocalories, and total protein intake while symbolic play capacity was related only to total protein intake. Significant increases in predictive variance occurred when the model was expanded to encompass caregiver behaviors as well as nutritional factors. For example, when nonverbal response to child vocalizations was used as the environmental measure, there was evidence of both coactive and synergistic interactions for comparisons involving cognitive development indicators. For symbolic play, an increase in predictive variance was found when the model included the multiplicative interaction of animal kilocalories by nonverbal response to vocalizations. Also observed was a buffering effect against poor psychosocial rearing conditions given the presence of adequate nutritional intake. These findings suggest the feasibility of multidimensional risk profiles, the provision of specific nutrients targeted at specific deficits, and multidisciplinary interventions.