Genetic and environmental influences on mothering of adolescents: a comparison of two samples

This study examined 2 samples of adolescents and mothers using a child-based design (Nonshared Environment in Adolescent Development [NEAD] project, N = 395 families) and a parent-based design (Twin Moms [TM] project, N = 236 twin family pairs) to compare genetic and environmental influences on mothering. For both samples, the same measures of positivity, negativity, control, and monitoring were used. The use of matched child-based and parent-based samples enabled passive and nonpassive genotype-environment (GE) correlations to be approximated, providing information about process. Passive GE correlations were suggested for mother's positivity and monitoring. For mother's negativity and control, primarily nonpassive GE correlations were suggested. In several cases, both types of GE correlation were indicated. Finally, observer ratings of negativity and monitoring were influenced only by environmental factors.     

Variation among developmental dyslexics: evidence from a printed-word-learning task

A word-learning task was used to investigate variation among developmental dyslexics classified as phonological and surface dyslexics. Dyslexic children and chronological age (CA)- and reading level (RL)-matched normal readers were taught to pronounce novel nonsense words such as veep. Words were assigned either a regular (e.g., "veep") or an irregular (e.g., "vip") pronunciation. Phonological dyslexics learned both regular and exception words more slowly than the normal readers and, unlike the other groups, did not show a regular-word advantage. Surface dyslexics also learned regular and exception words more slowly than the CA group, consistent with a specific problem in mastering arbitrary item-specific pronunciations, but their performance resembled that of the RL group. The results parallel earlier findings from Manis, Seidenberg, Doi, McBride-Chang, & Petersen [Cognition 58 (1996) 157-195] indicating that surface dyslexics and phonological dyslexics have a different profile of reading deficits, with surface dyslexics resembling younger normal readers and phonological dyslexics showing a specific phonological deficit. Models of reading and reading disability need to account for the heterogeneity in reading processes among dyslexic children.     

Executive self, self-esteem, and negative affectivity: relations at the phenotypic and genotypic level

Complementary approaches examined the relations among executive self, self-esteem, and negative affectivity. A cross-sectional (N = 4,242) and a longitudinal (N = 158) study established that self-esteem mediated the relation between executive self and negative affectivity. A 3rd study (N = 878 twin pairs) replicated this pattern and examined genetic and environmental influences underlying all 3 phenotypes. Covariation among the 3 phenotypes reflected largely common genetic influences, although unique genetic effects explained variability in both executive self and negative affectivity. Executive self was influenced by shared environmental influences unique from those affecting self-esteem and negative affectivity. Non-shared environmental influences accounted for the majority of variance in each construct and were primarily unique to each. The unique genetic and non-shared environmental influences support the proposition that the executive self, self-esteem, and negative affectivity capture distinct and important differences between people.     

The attenuating effect of role overload on relationships linking self-efficacy and goal level to work performance

The reported research examines the moderating effects of role overload on the antecedents and consequences of self-efficacy and personal goal level in a longitudinal study conducted in an industrial selling context. The results indicate that role overload moderates the antecedent effect of perceived organizational resources on self-efficacy beliefs. They also show that role overload moderates the direct effects of both self-efficacy and goal level on performance, such that these relationships are positive when role overload is low but not significant when role overload is high. Further, the results reveal a pattern of moderated mediation, in which goal level mediates the indirect effect of self-efficacy on performance when role overload is low but not when it is high. Implications for theory and managerial practice are discussed.     

Quantitative genetic analysis of latent growth curve models of cognitive abilities in adulthood

Though many cognitive abilities exhibit marked decline over the adult years, individual differences in rates of change have been observed. In the current study, biometrical latent growth models were used to examine sources of variability for ability level (intercept) and change (linear and quadratic effects) for verbal, fluid, memory, and perceptual speed abilities in the Swedish Adoption/Twin Study of Aging. Genetic influences were more important for ability level at age 65 and quadratic change than for linear slope at age 65. Expected variance components indicated decreasing genetic and increasing nonshared environmental variation over age. Exceptions included one verbal and two memory measures that showed increasing genetic and nonshared environmental variance. The present findings provide support for theories of the increasing influence of the environment with age on cognitive abilities.     

The Genetic and Environmental Relationship Between General and Specific Cognitive Abilities in Twins Age 80 and Older

In the first twin study of the old-old, individuals 80 years old and older, we examined the relationship between general and specific cognitive abilities from a genetic perspective. That is, we examined the extent to which genetic and environmental factors influence major group factors of cognitive abilities, independent of general cognitive ability. As part of the OctoTwin project in Sweden, general and specific cognitive abilities were assessed in 52 monozygotic and 65 same-sex dizygotic twin pairs 80 years old and older using a battery of seven tests that assess verbal, spatial, speed-of-processing, and memory performance. Results suggest that genetic effects associated with general cognitive ability ( g ) account for the correlation between g and verbal, spatial, and speed-of-processing abilities. No genetic influences were found for these specific cognitive abilities separate from g . In contrast, memory ability appears to be more distinct genetically from g than are other cognitive abilities. Comparison with younger samples suggests that cognitive abilities relating to speed of processing may be genetically dedifferentiated in the old-old.     

Attentional strategies in dichotic listening

A person can attend to a message in one ear while seemingly ignoring a simultaneously presented verbal message in the other ear. There is considerable controversy over the extent to which the unattended message is actually processed. This issue was investigated by presenting dichotic messages to which the listeners responded by buttonpressing (not shadowing) to color words occurring in the primary ear message while attempting to detect a target word in either the primary ear or secondary ear message. Less than 40% of the target words were detected in the secondary ear message, whereas for the primary ear message (and also for either ear in a control experiment), target detection was approximately 80%. Furthermore, there was a significant negative correlation between buttonpressing performance and secondary ear target-detection performance. The results were interpreted as being inconsistent with automatic processing theories of attention.     

Deafness and mother–child interaction: Scaffolded instruction and the learning of problem-solving skills

This study examines the effects of maternal teaching style on the developing problem-solving abilities of deaf and hearing pre-school children. Mothers and children from three matched groups, hearing mother-deaf child, hearing mother-hearing child, and deaf mother-deaf child, were videotaped while the mother instructed the child on a block construction task and again when the child attempted the task independently. Dependent measures were maternal instructional style and child performance. The mothers in the deaf mother-deaf child and hearing mother-hearing child dyads used appropriate scaffolding behaviour and their children were more likely to exhibit adept and independent problem-solving abilities than the deaf children of hearing mothers. The findings of this study support Vygotsky's notion of the ‘zone of proximal development’ and the concept of adult scaffolding of children's learning.     

Case vignette -- mandated child abuse reporting

Case Vignette: Martha Harris has been a licensed mental health professional for nearly a decade. As she arrived at her office early this morning, the phone was ringing. Speaking in a tremulous voice, the caller stated, "I was given your name by my internist, Dr. Williams. I think my husband may be abusing our 5-year-old sexually. Can you help?" After a few minutes of conversation, Martha offers to schedule a prompt appointment. The caller interrupts and asks, "You won't have to report this will you?" As a mandated reporter under the state's child protection statute, Martha has no choice but to inform the authorities; she tells the caller, who immediately hangs up. Suddenly, Martha realizes that she does not have the name or any other identifying information about the caller. A call to Dr. Williams results in a response that the internist does not want to "get involved." Commentators on this case are Richard Bourne, JD, PhD, one of whose special areas of expertise is child protection and related professional obligations; Eli H. Newberger, MD, a pediatrician with a special interest in child maltreatment; and C. Sue White, PhD, one of whose primary interests is how clinicians may inappropriately use techniques to interview children suspected of child sexual abuse, causing contaminating influences to interfere with children's memories for their own experiences.