Identifying shared environmental contributions to early substance use: the respective roles of peers and parents

Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c(2) =.51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use.     

Sustained attention and visual processing speed in children and adolescents with bipolar disorder and other psychiatric disorders

To investigate the cognitive functioning of children and adolescents with bipolar illness, 112 child and adolescent psychiatric inpatients and day-hospital patients at a state psychiatric hospital were administered the Wechsler Intelligence Scale for Children-III (WISC-III) as part of an admission psychological assessment. There were 22 patients with Bipolar Disorder and 90 with other psychiatric disorders; all were between 8 and 17 years of age. The patients with Bipolar Disorder had a mean age of 14 yr., a mean Verbal IQ of 78, a mean Performance IQ of 76, and a mean Full Scale IQ of 75. When their WISC-III scores were compared with those who had Schizophrenia Spectrum disorders (Schizophrenia and Schizoaffective Disorder), Psychosis Not Otherwise Specified, Attention Deficit Hyperactivity Disorder, and Conduct Disorder and Oppositional Defiant Disorder, there were no significant between-group mean differences for Verbal IQ, but patients with Bipolar Disorder had a significantly lower mean Performance IQ than those with ADHD and those with Conduct Disorder and Oppositional Defiant Disorder. Contrary to the expectation that the patients with Bipolar Disorder might have better sustained attention (higher Digit Span scores) than those with Schizophrenia Spectrum disorders and worse visual processing speed (lower Coding scores) than the other diagnostic groups, the bipolar patients' Digit Span and Coding scores did not differ significantly from those of the other groups. The patients with Psychosis, Not Otherwise Specified had significantly lower mean Performance IQ, Full Scale IQ, and Coding than the ADHD and the Conduct Disorder and Oppositional Disorder groups.     

Parental ratings of son's behavior problems in high-risk families: convergent validity,internal structure,and interparent agreement

In this research, we examined the convergent validity, internal structure, and interparent agreement of the Child Behavior Checklist (CBCL; Achenbach, 1991a) using data from a community sample of 317 high-risk families. The sample consisted of 218 families with alcoholism (biological mother, father, and son) and 99 matched comparison families without alcoholism; all families were intact and included a 3- to 5-year-old son at first contact. Evidence was found for the convergent validity of the CBCL. In addition, although interparent agreement was low, the internal structure was confirmed, and structural invariance was high between mothers and fathers and in families with and without alcoholism. The effects of parental psychological and cognitive functioning on parent agreement were examined and found to have a minimal effect on parent agreement. These results demonstrate the validity of the CBCL for use by parent raters with alcoholism and their sons and emphasize the importance of including both versus only 1 parent in research using the CBCL.     

The use of category and similarity information in limiting hypotheses

Memory &; Cognition - Previous studies have shown that adults usually select diverse evidence for generalizing hypotheses. We investigated what kind of evidence people select in another type of...     

Do humans ape? Or do apes human? Imitation and intention in humans (Homo sapiens) and other animals

A. Whiten, D. M. Custance, J.-C. Gomez, P. Teixidor, and K. A. Bard (1996) tested chimpanzees' (Pan troglodytes) and human children's (Homo sapiens) skills at imitation with a 2-action test on an "artificial fruit." Chimpanzees imitated to a restricted degree; children were more thoroughly imitative. Such results prompted some to assert that the difference in imitation indicates a difference in the subjects' understanding of the intentions of the demonstrator (M. Tomasello, 1996). In this experiment, 37 adult human subjects were tested with the artificial fruit. Far from being perfect imitators, the adults were less imitative than the children. These results cast doubt on the inference from imitative performance to an ability to understand others' intentions. The results also demonstrate how any test of imitation requires a control group and attention to the level of behavioral analysis.     

Examining the construct validity of the Eating Disorder Inventory

The construct validity of the Eating Disorder Inventory (EDI) was examined in 3 samples. An archival clinic sample (n = 318) of women completed the EDI, a structured interview, and the Millon Clinical Multiaxial Inventory-II (MCMI-II). Confirmatory factor analyses (CFAs) indicated that neither null nor 1-factor models of the EDI fit item-level or item-parcel data. The proposed 8-factor model did not fit at the item level but did fit item-parcel data. Reliability estimates of the 8 scales ranged from .82 to .93, and low-to-moderate interscale correlations among the eating and weight-related scales provided partial support for convergent validity. EDI personality scales showed moderate interscale correlations and were associated with MCMI-II scales. A final CFA of the EDI scales supported a 2-factor model (Eating and Weight, Personality) of the 8 EDI scales. Strong associations between depression and several EDI scale scores were found in a treatment study sample (n = 50). The archival clinic sample scored significantly higher on the 8 EDI scales than the nonpatient college comparison sample (n = 487).     

Benchmark Memories in Adulthood: Central Domains and Predictors of Their Frequency

This study extended earlier research on the reminiscence bump phenomenon in autobiographical memory by examining the central domains and predictors of benchmark memories from a life history timeline and from three selected significant events. Memories elicited by these methods demonstrated the reminiscence bump as occurring in early adulthood. The central domains representing this era involved events with family and relationships followed by those related to education and work. Individual differences in socio-emotional variables associated with self and identity formations (i.e., family climate, defensive style, self-complexity, and adult attachment) were associated with the reminiscence bump. These findings support the self-narrative hypothesis that the reminiscence phenomenon is related to the process of identity formation in late adolescence and early adulthood.     

A Multi-informant Multi-Measure Approach to the Two Factor Model of Emotion with Youth

The two-factor model of emotion clarifies the complexities of the relationship between anxiety and depression through their varying associations with positive and negative affect. Although this model’s structure has been studied in children, the lack of parent report measures on model-specific constructs has thus far prevented a multi-informant perspective on the model. Capitalizing on recent advancements in parent report assessment instruments, the present investigation aimed to confirm the two-factor model of emotion per child self-report; expand the model’s applicability to include parent report; and create a combined-informant model with a large number of parent-child dyad pairs (N?=?610). Structural equation modeling demonstrated good fit within parent and child informant models, but diminished fit for the multi-informant model. These results suggest a high degree of robustness with respect to informant type. Implications for the integration of multi-informant assessment information are discussed.     

Should Social Aggression be Considered “Antisocial”?

There is converging evidence that physical aggression and non-aggressive rule-breaking constitute meaningfully distinct, if somewhat overlapping, dimensions of antisocial behavior, with different developmental trajectories, demographic correlates, and etiologies. Social aggression can also be factor-analytically and demographically distinguished from physically aggressive and rule-breaking antisocial behavior. However, there is ongoing debate as to whether social aggression should also be considered “antisocial” in the way the term is commonly understood, given that socially aggressive behaviors are generally legal and nearly normative during adolescence. The current study sought to empirically evaluate the notion that social aggression constitutes a form of antisocial behavior that is separable from other forms of antisocial behavior. We thus conducted a preliminary study to examine whether social aggression was associated with other forms of antisocial behavior and a variety of correlates of antisocial behavior in a sample of 497 undergraduates. Analyses revealed that social aggression was independently associated with other measures of antisocial behavior, substance use and unethical behaviors, as well as the personality traits known to predict current and future antisocial behavior. These associations were particularly pronounced in women. Such findings are consistent with our hypothesis that social aggression constitutes a distinct form of antisocial behavior.     

Chimpanzees and bonobos exhibit divergent spatial memory development

Spatial cognition and memory are critical cognitive skills underlying foraging behaviors for all primates. While the emergence of these skills has been the focus of much research on human children, little is known about ontogenetic patterns shaping spatial cognition in other species. Comparative developmental studies of nonhuman apes can illuminate which aspects of human spatial development are shared with other primates, versus which aspects are unique to our lineage. Here we present three studies examining spatial memory development in our closest living relatives, chimpanzees (Pan troglodytes) and bonobos (P. paniscus). We first compared memory in a naturalistic foraging task where apes had to recall the location of resources hidden in a large outdoor enclosure with a variety of landmarks (Studies 1 and 2). We then compared older apes using a matched memory choice paradigm (Study 3). We found that chimpanzees exhibited more accurate spatial memory than bonobos across contexts, supporting predictions from these species’ different feeding ecologies. Furthermore, chimpanzees – but not bonobos – showed developmental improvements in spatial memory, indicating that bonobos exhibit cognitive paedomorphism (delays in developmental timing) in their spatial abilities relative to chimpanzees. Together, these results indicate that the development of spatial memory may differ even between closely related species. Moreover, changes in the spatial domain can emerge during nonhuman ape ontogeny, much like some changes seen in human children.