Trigeminal sensitivity to contact chemical stimulation: A new method and some results

Acquisition of knowledge about the chemical senses might be hastened if chemicals or techniques that permitted stimulation of either the common chemical sense, mediated by the trigeminal nerve, or the sense of smell, mediated by the olfactory nerve without concomitant stimulation of the other sense, were used. Flowing the nonodorized output of an olfactometer into one naris of subjects while velopharyngeal closure was maintained produced effluent flow from the contralateral naris. To prevent odorous molecules from reaching the olfactory epithelium, the contralateral naris was stimulated by applying diluted and undiluted chemical solutions directly to the septal squamous epithelium downstream from the olfactory mucosa. A series of five geometric dilutions of three chemicals and one saturated solution of a fourth were used. The weakest dilution of each chemical was an adequate olfactory stimulus. Two were known trigeminal stimulants (acetic acid and butanol), and two were rated low in trigeminal stimulatory capacity (phenethyl alcohol and vanillin). The results showed that this method was useful in determining the trigeminal threshold for some chemicals. When this method was used, saturated aqueous solutions of vanillin and phenethyl alcohol were clearly not detectable by the trigeminal receptors. The application of the undiluted vanillin and phenethyl alcohol yielded a clear sensation. This result may imply that there are no pure olfactory stimuli.     

Simultaneous optimization of factor assessibility and representativeness

P. M. Bentler has shown that Rao's canonical factor analysis is in effect a psychometric analysis, leading to factors that are maximally assessible from the data. He contrasts this with Kaiser and Caffrey's alpha factor analysis that leads to factors that maximally represent the true factors in the content domain. Noting the problems associated with factors that may be highly assessible, but not very representative, or vice versa, Bentler suggests the need for a technique that would, insofar as possible, be optimal with respect to both criteria. Such a technique is presented here, and is shown to resolve into a traditional scaling method, which in turn acquires a richer psychometric interpretation.The author would like to gratefully acknowledge support for this research from the Workshop in Political Theory and Policy Analysis (Indiana University) and Esco Research Associates. The paper benefitted substantially from the criticisms and suggestions of an anonymous referee.     

Modality and phonological similarity effects in serial recall: Does one’s own voice play a role?

Results of two experiments showed that the modality effect in serial recall of word lists is sharply reduced by high interitem phonological similarity and that the extent of this reduction is much the same irrespective of whether the lists are spoken by the subject or the experimenter. These findings contradict an account of the modality effect recently proposed by Richardson (1979), but the data are entirely consistent with the belief that the effect originates in echoic memory.     

The belief in a just world: an examination of reliability estimates across three measures

In this study, we utilized reliability generalization procedures to examine internal consistency estimates across 3 scales measuring the belief in a just world. The distribution of reliability estimates for the measures suggest low to moderate ranges of internal consistency reliability coefficients. The Global Belief in a Just World Scale (Lipkus, 1991) produced the highest average reliability score (alpha = .81) compared to the Just World Scale (Rubin & Peplau, 1973; alpha = .64) and the Just World Scale Revised (Rubin & Peplau, 1975; alpha = .68).     

The quality of caregiving in child care: relations to teacher complexity of thinking and perceived supportiveness of the work environment

This study examined the relationship between the complexity of thinking about children by child care teachers and observed teachers' caregiving for infants and toddlers. It was hypothesized that the perceived supportiveness of the work environment would affect this relationship. Fifty‐six child care teachers completed a survey assessing complexity of thinking about children's behaviour as well as a measure of the perceived opportunities for professional development. Teachers' quality of caregiving was assessed using the Caregiver Interaction Scale. Planned contrasts revealed that when professional development opportunities were perceived unfavourably, teachers who were complex in thinking about children's behaviour provided significantly more sensitive care than did teachers who were less complex in their thinking. Findings indicate that the complexity of teachers' thinking about children may be very important in understanding teacher's sensitivity when the quality of the work environment is poor. High‐quality work environments may buffer teachers with less complexity of thinking from being less sensitive with children. Efforts to improve quality of care could focus on individual teachers to improve their complexity of thinking as well as on the work environment to make it more supportive of teachers' professional development. Copyright © 2008 John Wiley & Sons, Ltd.     

A behavioral genetic study of trait emotional intelligence

Numerous models of emotional intelligence (EI) have proposed the existence of hitherto undiscovered mental abilities, competencies, and skills. The theory of trait emotional intelligence suggests that the content domains of these models invariably contain permutations of personality traits. The two studies in this article examine the heritability of trait EI scores with a view to demonstrating empirically that the construct has a similar level of genetic influence as other personality traits. Study 1 was a family design of 133 high-school students and their parents. Regressions of offspring on midparent scores suggested median upper-limit heritability estimates of .18 at facet level, .25 at factor level, and .32 at the global trait EI level. Study 2 was a twin design (213 pairs of monozygotic [MZ] twins and 103 pairs of dizygotic [DZ] twins). It yielded median heritabilities of .42 for the facets, .44 for the factors, and .42 for global trait EI. Overall, our findings are in accordance with studies of the major personality dimensions and provide further empirical support for the conceptualization of EI as a personality trait.     

Family‐level coparenting processes and child gender as moderators of family stress and toddler adjustment

The goal of this multi‐method study was to examine how child gender and coparenting processes influence associations between family stress and toddlers' social adjustment. The participants, 104 dual‐earner couples and their 2‐year‐old children, were videotaped in their home during a freeplay activity. Mothers and fathers completed questionnaires about stress in their roles as partners, workers, and parents and their child's social–emotional adjustment. Consistent with previous research, higher levels of family stress were associated with poorer adjustment for children. Family harmony, represented by warmth and cooperation, was significantly associated with fewer internalizing problems for children even when family stress was considered. Conversely, coparental banter or ‘playful humour’ between parents moderated the nature of the association between family stress and children's adjustment. Banter between parents was especially protective for girls suggesting that, even in families with toddler‐aged children, gender plays an important role in family‐level coparenting processes. Future research needs to consider more fully the impact that child characteristics, such as gender, have on the interplay between the family context and children's development. Copyright © 2008 John Wiley & Sons, Ltd.