The phenotypic consequences of MECP2 mutations extend beyond Rett syndrome

Although MECP2 was initially identified as the causative gene in classic Rett syndrome (RTT), the gene has now been implicated in several phenotypes that extend well beyond the clinically defined disorder. MECP2 mutations have been found in people with various disorders, including neonatal onset encephalopathy, X-linked recessive mental retardation (MRX), classic and atypical RTT, autism, and Angelman syndrome, as well as mildly affected females and normal carrier females. To make matters more complex, in approximately 20% of classic sporadic RTT cases and more than 50% of affected sister pairs, no mutation in MECP2 has been found. X-chromosome inactivation patterns can clearly affect the phenotypic expression in females, while the effect of the type and position of the mutation is more apparent in the broader phenotype than in RTT. Both males and females are at risk, although an excess of paternally derived mutations are found in most cases of classic RTT. Thus, because of the range of disparate phenotypes, the gene may account for a relatively large portion of mental retardation in the population.     

Children's perception of media-portrayed sex roles

The immediate impact on preschool and elementary school children of a televised presentation in which the traditional sex roles of physician and nurse were reversed was examined. After viewing a videotape of a male nurse and a female physician, subjects were asked to identify photographs or names of the physician and nurse. Preschool, first-, and fourth-grade children selected male names or pictures for the physician and female names or pictures for the nurse, thereby reversing genders. Their immediate recall appeared strongly influenced by their stereotypes rather than by the film they had just viewed. Seventh-grade children correctly identified the names of the physician and nurse.The authors wish to thank Dr. Edward F. Meydrech, Assistant Professor, Department of Preventive Medicine and Chief of the Division of Biostatistics, University of Mississippi Medical Center, for his invaluable assistance in the analysis of the data.     

Discrimination of second-formant-like frequency transitions

Discrimination of two types of simulated single-second-formant: frequency transitions was studied, transitions where members of a stimulus set shared the same onset frequency and transitions where stimuli of a set shared the same offset frequency. Experiment 1 employed an adaptive procedure to measure just-noticeable differences for transitions that increased in frequency. Experiment 2 obtained complete psychometric functions, based on a three-interval,forced choice procedure,for transitions that either increased or decreased in frequency. In both experiments, better discrimination occurred for longer stimuli, measured in hertz/millisecond, and for transitions that shared the same onset frequency. There were no differences, in Experiment 2, between discrimination of rising and falling transitions. Results are considered from several theoretical perspectives.     

Discrimination of second-format-like frequency transitions

Discrimination of two types of simulated single-second-format frequency transitions was studied, transitions where members of a stimulus set shared the same onset frequency and transitions where stimuli of a set shared the same offset frequency. Experiment 1 employed an adaptive procedure to measure just-noticeable differences for transitions that increased in frequency. Experiment 2 obtained complete psychometric functions, based on a three-interval, forced-choice procedure, for transitions that either increased or decreased in frequency. In both experiments, better discrimination occurred for longer stimuli, measured in hertz/millisecond, and for transitions that shared the same onset frequency. There were no differences, in Experiment 2, between discrimination of rising and falling transitions. Results are considered from several theoretical perspectives.     

A sensory basis for the lateral difference in the newborn infant's response to somesthetic stimulation

To determine whether lateral differences in the newborn infant's response to somesthetic stimulation are a consequence of lateral differences in sensitivity or whether they are the result of lateral differences in motor tendencies, cardiac response to stimulation of the left and right perioral region was examined. Cardiac acceleration occurred significantly more frequently to stimulation of the right than to stimulation of the left. Ipsilateral head turning also occurred more reliably to stimulation of the infant's right side than to stimulation of his left side. Evidence of reliable lateral differences in cardiac acceleration responses even under conditions in which the effects of lateral differences in head turning were removed suggested that the laterally differentiated cardiac responsiveness was not merely a function of increased motor activity consequent upon stimulation of the infant's right side but reflected a difference in sensitivity at the infant's two sides as well.     

Family interference with work and workplace cognitive failure: The mitigating role of recovery experiences

The first goal of this study was to test whether family interference with work (FIW) is positively related to increased workplace cognitive failure (WCF), which is defined as errors made at work that indicate lapses in memory (e.g., failing to recall work procedures), attention (e.g., not fully listening to instruction), and motor function (e.g., unintentionally pressing control switches on machines). The second goal was to determine whether recovery experiences (psychological detachment and relaxation) during free time on evenings and weekends can mitigate (weaken) the positive relationship between FIW and WCF. Results based on data collected from 118 water utility employees suggest that FIW is indeed related to more WCF, and that psychological detachment from work mitigates this positive relationship. It was relatively less evident that relaxation plays such a mitigating role.     

A longitudinal study of the effects of dual-earner couples' utilization of family-friendly workplace supports on work and family outcomes

Little research exists on the effects of the utilization of workplace supports on work-family conflict and job satisfaction. With family systems theory as a framework, 2 waves of national survey data were collected from 234 couples (N = 468) caring for children and for aging parents. Data were analyzed with structural equation modeling techniques. Longitudinal results indicate that individuals' use of workplace supports was related to work-family conflict in the direction opposite to expectations and was related to job satisfaction in the direction consistent with expectations. Differential effects for wives versus husbands were found. In addition, couples' use of workplace supports was only minimally related to wives' outcomes. Results are discussed in terms of gender differences, family systems theory, and methodological and measurement issues related to the longitudinal study of utilization of workplace supports.     

Age differences in discrimination of simulated single-formant frequency transitions

We studied auditory discrimination of simulated single-formant frequency transitions that resembled portions of certain speech consonants. Significant age differences in transition discrimination occurred; both children and older adults required larger acoustic differences between transitions for discrimination than did teenagers/young adults. Longer transitions were more easily discriminated than shorter transitions by all listeners, and there were no differences between discriminations of rising and falling transitions. Teens/young adults and older adults, but not children, required larger frequency differences to discriminate frequency transitions followed by a steady-state sound than for transitions alone. There were also age differences in discrimination of steady-state sounds. These developmental-perceptual differences may help explain why children and older adults who have good pure-tone sensitivity may experience difficulty in understanding speech.