On the current status of the evolutionary theory of behavior dynamics

The evolutionary theory of behavior dynamics is a complexity theory that instantiates the Darwinian principles of selection, reproduction, and mutation in a genetic algorithm. The algorithm is used to animate artificial organisms that behave continuously in time and can be placed in any experimental environment. The present paper is an update on the status of the theory. It includes a summary of the evidence supporting the theory, a list of the theory's untested predictions, and a discussion of how the algorithmic operations of the theory may correspond to material reality. Based on the evidence reviewed here, the evolutionary theory appears to be a strong candidate for a comprehensive theory of adaptive behavior.     

Evidence for a sensitive period in the effects of early life stress on hippocampal volume

Exposure to stress has been causally linked to changes in hippocampal volume (HV). Given that the hippocampus undergoes rapid changes in the first years of life, stressful experiences during this period may be particularly important in understanding individual differences in the development of the hippocampus. One hundred seventy‐eight early adolescents (ages 9–13 years; 43% male) were interviewed regarding exposure to and age of onset of experiences of stress; the severity of each stressful event was rated by an objective panel. All participants underwent structural magnetic resonance imaging, from which HVs were automatically segmented. Without considering the age of onset for stressful experiences, there was a small but statistically significant negative association of stress severity with bilateral HV. When considering the age of onset, there was a moderate and significant negative association between stress severity during early childhood (through 5 years of age) and HV; there was no association between stress severity during later childhood (age 6 years and older) and HV. We provide evidence of a sensitive period through 5 years of age for the effects of life stress on HV in adolescence. It will be important in future research to elucidate how reduced HV stemming from early life stress may contribute to stress‐related health outcomes.     

A comparison of computer‐assisted and therapist‐led instruction for children with autism spectrum disorder

The current investigation applied a model of assessment‐based instruction to an evaluation of the efficacy and efficiency of computer‐assisted and therapist‐led instruction on skill acquisition for 3 participants with autism spectrum disorder. We also evaluated the participant's attending during instruction and the social validity of each format of instruction. The results showed that computer‐assisted instruction was most efficient for 2 of the 3 participants, although attending varied across instructional formats. In addition, the social validity of instructional formats varied across participants.     

An assessment of differential reinforcement procedures for learners with autism spectrum disorder

Differential reinforcement procedures may promote unprompted correct responding, resulting in a quicker transfer of stimulus control than nondifferential reinforcement. Recent studies that have compared reinforcement arrangements have found that the most effective arrangement may differ across participants. The current study conducted an assessment of differential reinforcement arrangements (i.e., quality, schedule, and magnitude) and nondifferential reinforcement to identify the most effective arrangement for each participant. The assessment phase showed that the quality arrangement was the most efficient for all participants during auditory‐visual matching. Next, a validation phase was conducted to evaluate whether the assessment would predict the most effective arrangement across multiple skills. The results from the assessment phase were validated for all participants for the same skill. However, the results were only validated for one participant during the other skills (i.e., tact and intraverbal). The results are discussed in light of previous research and future areas of research.     

Examining the Construct Validity of the MMPI–2–RF Interpersonal Functioning Scales Using the Computerized Adaptive Test of Personality Disorder as a Comparative Framework

This study aimed to examine the construct validity of the Minnesota Multiphasic Personality Inventory–2 Restructured Form (MMPI–2–RF) interpersonal functioning scales (Ben-Porath &; Tellegen, 2008/2011 Ben-Porath, Y. S., &; Tellegen, A. (2011). MMPI–2–RF (Minnesota Multiphasic Personality Inventory–2 Restructured Form) manual for administration, scoring, and interpretation. Minneapolis: University of Minnesota Press. (Original work published 2008) [Google Scholar]) using as a criterion measure the Computerized Adaptive Test of Personality Disorder–Static Form (CAT–PD–SF; Simms et al., 2011 Simms, L. J., Goldberg, L. R., Roberts, J. E., Watson, D., Welte, J., &; Rotterman, J. H. (2011). Computerized adaptive assessment of personality disorder: Introducing the CAT–PD project. Journal of Personality Assessment, 93, 380–389.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). Participants were college students (n = 98) recruited through the university subject pool. A series of a priori hypotheses were developed for each of the 6 interpersonal functioning scales of the MMPI–2–RF, expressed as predicted correlations with construct-relevant CAT–PD–SF scales. Of the 27 specific predictions, 21 were supported by substantial (≥ |.30|) correlations. The MMPI–2–RF Family Problems scale (FML) demonstrated the strongest correlations with CAT–PD–SF scales Anhedonia and Mistrust; Cynicism (RC3) was most highly correlated with Mistrust and Norm Violation; Interpersonal Passivity (IPP) was most highly correlated with Domineering and Rudeness; Social Avoidance (SAV) was most highly correlated with Social Withdrawal and Anhedonia; Shyness (SHY) was most highly correlated with Social Withdrawal and Anxioiusness; and Disaffiliativeness (DSF) was most highly correlated with Emotional Detachment and Mistrust. Results are largely consistent with hypotheses suggesting support for both models of constructs relevant to interpersonal functioning. Future research designed to more precisely differentiate Social Avoidance (SAV) and Shyness (SHY) is suggested.     

Examining the Association Between Body Mass Index and Weight Related Quality of Life in Black and White Women

Obesity not only increases risk for morbidity/mortality, but also impacts the quality of life of obese individuals. In the United States, black women have the highest prevalence of obesity of any other group with approximately 80% of black women over age 20 having a body mass index (BMI)????25?kg/m². We aimed to examine the association between BMI and quality of life in this high risk population compared to this association in white women, using the Impact of Weight on Quality of Life (IWQOL)-Lite questionnaire. Data from 172 black women (mean BMI?=?35.7; age?=?40.5) and 171 white women (mean BMI?=?35.5; age?=?40.4) were collected between 2000 and 2010 analyzed in 2010. The mean IWQOL-Lite total score was 81.6 for black women compared to 66.9 for white women, a statistically significant difference. Hierarchical linear regression models revealed a significant BMI-by-race interaction indicating that the relationship between BMI and IWQOL-Lite score was moderated by race. Our findings suggest notable differences in weight-related quality of life in black and white women. At similar BMIs, black women consistently reported better quality of life than white women on all IWQOL-Lite subscales. The greatest difference in IWQOL-Lite scores between black and white women was seen in the self-esteem subscale. Additional research is needed to understand how to incorporate the weight perspectives of black women into weight management messages and interventions.     

Watching Aggressive, Attractive, Female Protagonists Shapes Gender Roles for Women Among Male and Female Undergraduate Viewers

The impact of exposure to media representations of aggressive, attractive, female protagonists on audiences?? gender role expectations for women was explored through a laboratory experiment with 122 undergraduates from a large university on the west coast of the United States. Participants viewed a segment of a major Hollywood motion picture that featured a female protagonist who was either highly attractive or less attractive and either highly aggressive or not aggressive. Viewing clips featuring a female protagonist who was both aggressive and stereotypically attractive led to greater endorsement of stereotypically feminine and stereotypically masculine gender role expectations for women. The effect on endorsement of stereotypically masculine expectations was partially mediated by the perception that the protagonist was a good role model for women. Although women endorsed both feminine and masculine gender role expectations for women more strongly than men, the effects of exposure to aggressive, attractive, female protagonists were similar for both male and female participants. Results are discussed in terms of gender stereotype activation and superwoman expectations for women.     

An Examination of the Factor,Convergent, and Discriminant Validity of the Behavioral Inhibition System and Behavioral Activation System Scales

The Behavioral Inhibition System and Behavioral Activation System Scales (BIS/BAS scales) are the most widely used measures designed to assess Gray’s Reinforcement Sensitivity Theory. However, questions remain regarding its factor, convergent, and discriminant validity. We assessed these properties in two samples of undergraduates (N = 723, N = 103). In Study 1, confirmatory factor analysis supported previous findings that suggested removal of several items, resulting in acceptable fit for a four-factor model. Convergent and discriminant validity were assessed for the original and revised scales. In Study 2, a public speaking task was used to assess validity of the scales in reference to positive/negative affect. Convergent and discriminant validity for the revised scales were not substantially different from the original scales. We suggest that future researchers should consider the use of the revised measure we describe. We also suggest that the creation of a revised BIS/BAS scale using new items may be warranted.     

Prenatal depression effects and interventions: A review

This review covers research on the negative effects of prenatal depression and cortisol on fetal growth, prematurity and low birthweight. Although prenatal depression and cortisol were typically measured at around 20 weeks gestation, other research suggests the stability of depression and cortisol levels across pregnancy. Women with Dysthymia as compared to Major Depression Disorder had higher cortisol levels, and their newborns had lower gestational age and birthweight. The cortisol effects in these studies were unfortunately confounded by low serotonin and low dopamine levels which in themselves could contribute to non-optimal pregnancy outcomes. The negative effects of depression and cortisol were also potentially confounded by comorbid anxiety, by demographic factors including younger age, less education and lower SES of the mothers and by the absence of a partner or a partner who was unhappy about the pregnancy or a partner who was depressed. Substance use (especially caffeine use) was still another risk factor. All of these problems including prenatal depression, elevated cortisol, prematurity and low birthweight and even postpartum depression have been reduced by prenatal massage therapy provided by the women's partners. Massage therapy combined with group interpersonal psychotherapy was also effective for reducing depression and cortisol levels. Several limitations of these studies were noted and suggestions for future research included exploring other predictor variables like progesterone/estriol ratios, immune factors and genetic determinants. Further research is needed both on the potential use of cortisol as a screening measure and the use of other therapies that might reduce prenatal depression and cortisol in the women and prematurity and low birthweight in their infants.     

Prenatal dysthymia versus major depression effects on the neonate

Depressed pregnant women were classified as dysthymic or major depression disorder based on the Structured Clinical Interview for Depression and followed to the newborn period. The newborns of dysthymic versus major depression disorder mothers had a significantly shorter gestational age, a lower birthweight, shorter birth length and less optimal obstetric complications scores. The neonates of dysthymic mothers also had lower orientation and motor scores and more depressive symptoms on the Brazelton Neonatal Behavioral Assessment Scale. These findings were not surprising given the elevated cortisol levels and the inferior fetal measures including lower fetal weight, fetal length, femur length and abdominal circumference noted in our earlier study on fetuses of dysthymic pregnant women.