Preschool children's comprehension and production of directive forms

Thirty preschool children, 10 each at the 3-,4-, and 5-year-old levels, participated in two structured tasks designed to assess both comprehension and production of a full range of directive forms. In contrast to previous reports, the results indicated no significant differences in directive comprehension or production as a function of age; children in all age groups demonstrated the ability to understand and verbally encode the intent of most types of directive forms. However, the two most implicit forms, Question Directives and Hints, were complied with significantly less frequently than the more explicit forms, and were uused less often in the production task. The present findings indicate the importance of analyzing directive forms along a continuum of explicitness rather than dichotomizing them as direct versus indirect. Finally, the results are interpreted as providing indirect support for the general notion that mastery of some implicit forms may be achieved later than the acquisition of more explicit forms.     

The perceived support network inventory

The development and psychometric investigation of the Perceived Support Network Inventory (PSNI), a measure of perceived social support, is described. A group of 146 introductory psychology students participated in a test-retest study design that collected reliability, internal consistency, and construct, convergent, and discriminant validity data on the scale. In addition, a contrast group of 28 Counseling Center clients was administered the PSNI. Test-retest reliability of the PSNI total score and subscale scores ranged from .72 to .88. Internal consistency for the PSNI was .77. Construct validity estimates ranged from .21 to .57. Convergent validity estimates varied from -.25 to .20. Discriminant validity estimates varied from -.11 to .19. Sample differences between introductory psychology student mean PSNI total and subscale scores and Counseling Center client mean PSNI total and subscale scores proved significant. Recommendations for subsequent research and future application are offered.     

Effects of preexposure flavor concentration on conditioned aversion and neophobia

In Experiment 1, 128 experimentally naive, water-deprived rats (Rattus norvegicus) received pretraining access to either 0.25 or 1.5% saccharin, distilled water, or 2.0% saline, followed either by a pairing of 0.25 or 1.5% saccharin with an intraperitoneal injection of 0.15 M lithium chloride (LiCl) or by a pairing of distilled water with LiCl. Preexposure to either saccharin concentration reliably reduced conditioned aversion effects to 0.25% saccharin, relative to that for preexposure to distilled water or saline. But only preexposure to 1.5% saccharin reduced aversion effects to that concentration. In Experiment 2, 48 naive, water-deprived rats received preexposure procedures as in Experiment 1. Afterwards, the rats were tested for neophobia to 0.25 or 1.5% saccharin. Neophobia was reliably greater to the 1.5% concentration. However, preexposure to either saccharin concentration obliterated evidence for neophobia to saccharin, relative to that following preexposure to distilled water or saline.     

Selective association in conditioned stress-induced analgesia: functional differences in interoceptive and exteroceptive sensory pathways

Rats were used to determine whether stress-induced analgesia (SIA) can be produced by conditioning with interoceptive stimuli (LiCl) as with exteroceptive stimuli (footshock). SIA was measured using a tail-flick test. As expected, unavoidable footshock as well as conditioning with footshock produced SIA. In contrast, conditioning with LiCl failed to cause SIA. The findings support the notion of functional differences in neural substrates for conditioning by exteroceptive and interoceptive cue.     

Differential ethanol olfactory experiences affect ethanol ingestion in preweanlings but not in older rats

Preweanling (21 days old) and adult (60-80 days old) rats were exposed to ethanol odor either paired with the early stages of apomorphine-induced toxicosis, paired with the recovery from toxicosis, or unpaired with the induction of distress. Twenty four hours later, ethanol preferences were measured in a spatial olfactory test (ethanol vs lemon odor) or a drinking test (5.6% v/v ethanol vs 0.25% w/v citric acid solutions). During the olfactory test both young and adult rats expressed substantial ethanol odor aversions when previously exposed to this odor paired with toxicosis. However, changes in ethanol intake became apparent only in preweanling subjects. Preweanlings which received the ethanol odor paired with illness drank significantly less of the ethanol solution relative to controls, while subjects experiencing the odor paired with recovery from distress significantly increased their consumption of the ethanol solution. These prior aversive and appetitive olfactory experiences had no effect upon ethanol intake in adult rats. These results implicate both an ontogenetic and a sensorial factor in the regulation of ethanol intake.     

Suppression of corticosterone synthesis alters the behavior of hippocampally lesioned rats

The suppression of corticosterone synthesis with metyrapone (25 mg/kg) reduced the hyperactivity and altered the exploratory activity of hippocampally lesioned animals (HPC) in the open field to the level of cortical and sham controls (Experiment 1). In a second experiment, corticosterone (600 micrograms/kg) pretreatment 2 h, but not 1 h, before metyrapone partially restored the hyperactivity of HPC animals that had been decreased by the corticosteroid-suppressant drug. Alterations in exploratory behavior induced by metyrapone were also prevented by corticosterone pretreatment. The results suggest that the suppression of corticosterone in hippocampally lesioned animals produces a normalization of behavior that can be prevented by pretreatment with corticosterone.     

Parent-infant resemblance for general and specific cognitive abilities in the Colorado adoption project

Previous publications emanating from the Colorado Adoption Project have reported significant relationships between parental general cognitive ability (g) and infant Bayley MDI scores. The present study compared infant Bayley factor scores representing separable dimensions of infant cognition with parental general and specific cognitive abilities for 182 adoptive families and 164 nonadoptive families. Parent/offspring correlations between 12-month Bayley factors and parental cognitive abilities suggest only minimal relationships for both parental g and specific abilities. At 24 months, more parent/offspring resemblance was present; moreover, Bayley factors that were related to parental cognition tended to be related to parental g, not to specific abilities. The finding of significant parent/offspring relationships at 24 months between biological parents and their adopted-away infants, as well as between nonadoptive parents and their infants, suggests some genetic continuity from infancy to adulthood.     

Correlates of adult and child perceptions of social competency

In this study, the relationship between two commonly used measures of social competency, peer ratings of perceived status and adult ratings of assertiveness, were examined. In Phase I, high and low sociometric status children were videotaped responding to a series of role-play scenes; performance on these scenes was then rated retrospectively by adults for overall assertiveness. In Phase II, a second group of children who were unfamiliar with the videotaped children observed the taped scenes and provided ratings of likability, intelligence, working together, and attractiveness. In general, results revealed that children and adults differed in their ratings of the videotaped children. Further, boys used different cues in their ratings than did girls. More specifically, the sociometric status of girls was related to perceived attractiveness, whereas the sociometric status of boys was more closely related to perceived intelligence. Such findings suggest that children and adults look for and use different cues in their judgments. Given these differences, it is concluded that child and adult ratings should not be used interchangeably in the assessment of, and evaluation of, social competency in children.Portions of this research were supported by a grant from the Virginia Department of Criminal Justice Services.