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OBJECTIVE Prior research has found a positive association between the quality or adjustment of an individual's intimate relationship, such as marriage, and their physical health. However, it is possible that this association may be due, at least in part, to confounding variables (i.e., variables that are causally associated both with relationship adjustment and health and could account for their covariation), including genetically influenced confounds. This study was conducted using a genetically informative sample of twins to examine the association between intimate relationship adjustment and self-rated health, accounting for unmeasured genetic and environmental confounds. METHOD A Swedish sample of 539 monozygotic and dizygotic twins (321 male twin pairs and 218 female twin pairs) and their spouse or long-term partner completed self-report measures of relationship adjustment and health. RESULTS Relationship adjustment was positively associated with self-rated health in male and female twins. For male twins, nonshared environmental influences largely accounted for the association between relationship adjustment and health; for female twins, this association was generally explained by shared and nonshared environmental influences. For male twins, results obtained from partners' reports of relationship adjustment were largely consistent with those obtained from twins' reports. CONCLUSIONS Results suggest that the association between relationship adjustment and self-rated health remains after accounting for shared genetic influences, and that nonshared environmental influences, such as partners' characteristics, account for the association between relationship adjustment and self-rated health in men. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

This study was conducted to estimate the magnitude of genetic and environmental influences on the association between three indices of subjective well-being (i.e., life satisfaction, positive affect, negative affect) and positive and negative components of marital adjustment (i.e., spousal support, spousal strain) in a sample of adult married twin pairs (N = 453 pairs). Results indicated that subjective well-being and marital adjustment were significantly associated (particularly in women), that there were gender differences in the magnitude of genetic and environmental influences on this covariation, and that this association was largely influenced by genetic factors in women and genetic and nonshared environmental factors in men. These findings highlight the importance of using genetically informed research to evaluate the genetic and environmental influences on the covariation between marital adjustment and individual outcomes such as subjective well-being.

We examined the associations between language skills and concern and disregard for others in young children assessed longitudinally at ages 14, 20, 24, and 36 months, testing the hypothesis that language skills have a specific role (distinct from that of general cognitive ability) in the development of concern and disregard for others. We found that higher language skills predicted higher concern for others and lower disregard for others even after controlling for general cognitive ability, whereas the association between general cognitive ability and concern/disregard for others was not significant after controlling for language skills. Language skills at 14 months predicted concern for others at 36 months, and results suggested that the relations between language skills and concern and disregard for others begin early in development. Gender differences in concern and disregard for others were at least partially explained by differences in language skills. These results support the specific role of language skills in concern and disregard for others.

The authors examined the validity of a method commonly used to test alternative hypotheses regarding the causes of comorbidity: the examination of underlying deficits of comorbid disorders. The authors simulated data in which the true causes of comorbidity were known, then compared the patterns of underlying deficits of the comorbid disorders found in the simulated data with the predicted results. The method of examining the underlying deficits of comorbid disorders could distinguish between several comorbidity models, including those that could not be distinguished well using other methods. The ability to distinguish the correct model decreased as the sample size and the correlation between the underlying deficits and the symptom scores decreased, suggesting that the issue of power should be considered carefully.

A meta-analysis of 51 twin and adoption studies was conducted to estimate the magnitude of genetic and environmental influences on antisocial behavior. The best fitting model included moderate proportions of variance due to additive genetic influences (.32), nonadditive genetic influences (.09), shared environmental influences (.16), and nonshared environmental influences (.43). The magnitude of familial influences (i.e., both genetic and shared environmental influences) was lower in parent-offspring adoption studies than in both twin studies and sibling adoption studies. Operationalization, assessment method, zygosity determination method, and age were significant moderators of the magnitude of genetic and environmental influences on antisocial behavior, but there were no significant differences in the magnitude of genetic and environmental influences for males and females.

Approximately 5% of children are affected by attention-deficit/hyperactivity disorder (ADHD), and more boys are affected than girls. This study examined the magnitude of genetic and environmental influences on ADHD and several questions regarding sex differences in its prevalence and liability. The participants were 2,391 twin and sibling pairs from Australia, ages 3-18. ADHD symptoms in the general population were highly heritable (h2 = .85-.90), as were deviant ADHD scores in the selected population. The magnitude of familial influences was similar for boys and girls, although there were shared environmental influences on ADHD in girls but not boys and dominance genetic influences on ADHD in boys but not girls. Specific genetic and environmental influences were highly similar for boys and girls. Evidence supported the polygenic multiple threshold model rather than the constitutional variability model of sex differences in ADHD.

In 3 experiments, the nature of the events that interfere with spatial working memory was examined in order to clarify the roles of imagery, attention, and other processes in the short-term maintenance of location information. Looking and pointing at secondary task stimuli selectively interfered with memory for the locations of primary task stimuli. Secondary tasks that involved either mentally rotating primary task stimuli or making color or shape discriminations about primary or secondary task stimuli interfered with spatial working memory only if the required response was visually guided, but not if the response was verbal. Taken together, these findings support P.S. Goldman-Rakic's (1987) hypothesis regarding multiple representational domains and are consistent with known properties and connections of neurons believed to subserve the perception and maintenance of spatial information. A working memory task may be defined as one that requires holding onto information for a short time while it or other information is processed. Baddeley has proposed that there is a working memory system, specialized for concurrent storage and manipulation of information that is engaged by such tasks (for a recent overview, see Baddeley & Hitch, 1994). On the basis of studies of both intact and brain-damaged subjects (for a review, see Gathercole, 1994), Baddeley and his colleagues have divided the working memory system into three components: a phonological store for verbal information, a visuospatial sketchpad for visuospatial information, and a central executive that directs activities involved in manipulating and maintaining information in the two specialized stores. Perhaps the most studied example is the role of covert articulatory rehearsal in refreshing information in the phonological store. Performing a secondary task that requires articulation of verbal material decreases verbal memory span, a finding consistent with the hypothesized role of subvocalization in maintaining verbal information (e.g., Baddeley, Lewis, & Vallar, 1984). Much of the supporting evidence for the visuospatial component of Baddeley's model also comes from studies that use dual task procedures. These studies were designed to determine whether visuospatial and verbal working memory involve separate resources, and they have demonstrated that secondary verbal tasks interfere with memory for verbal information to a much greater extent than they interfere

The primary goal of the current study was to examine the degree of independence of the age-related influences on measures sometimes postulated to be sensitive to functioning in different regions of the brain. It is often assumed that levels of performance on different cognitive measures and the age-related effects on those measures are determined by separate and distinct mechanisms. In the case of measures from neuropsychological tests, the discovery of selective impairments by individuals with damage in particular regions of the brain has led to the inference that various brain structures are specialized for different types of processing. When combined with results indicating age-related deficits on those measures, these findings have led to speculation that certain regions of the brain are more sensitive to age-related decline than others. For example, at different times it has been suggested that the