Syllogistic reasoning in varied narrative contexts: Aspects of logical and linguistic development

This experimental study examined the effects on syllogistic reasoning in grades 6 and 12 of certain contextual narrative variables. The experimental task consisted of 27 varied syllogistic problems based on information contained in three narrative texts—a fantasy passage, a realistic passage, and a contractual passage. Versions of these texts were constructed for each group reading level. Analysis of the data revealed several significant interactions between subject groups and treatment variables. In particular, younger subjects performed better than grade 12 subjects on problems following the fantasy narrative, while the older subjects did better with the other two passages. The results suggest that some orthodox views about concrete-versus formal-operational reasoning abilities and about the distinction between abstract and concrete materials need to be reassessed within a discourse-processing framework that is sensitive to the discourse worlds in which problems are embedded.The author wishes to acknowledge the support of an Isaak Walton Killam Doctoral Scholarship for this research.     

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.     

Self-labeling by educably mentally retarded high school students in their mainstream and special education classes

Educably mentally retarded (EMR) students and nonhandicapped students from their mainstream classes completed semantic differential ratings of a stereotypic popular teen-ager, juvenile delinquent, and special education student. Subjects also rated their global self-concepts and situation-specific self-concepts within the mainstream and the special class settings. Ratings were done at the beginning (Time 1) and the end (Time 2) of a semester. Results showed that mainstream classes did not "de-label" EMR students. Within the mainstream class, the number of EMR students who saw themselves as similar to a special education student significantly increased over time. Moreover, at Time 2, EMR students were more likely to think of themselves as similar to a special education student in their mainstream class than in their special education class. However, EMR subjects' global self-concepts did not change. Implications for mainstreaming are discussed.     

Continuous monitoring of human contingency judgment across trials

Recent evidence suggests that people are sensitive to the degree of contingency between their actions and ensuing outcomes, but little is known about the way in which such contingency judgments develop as more and more information about the contingency is provided. Three experiments examined this issue in the context of a video game. In Experiment 1, it was found that contingency judgments follow growth functions: When the contingency was positive, judgments increased toward a positive asymptote, and when the contingency was negative, judgments decreased toward a negative asymptote. When the contingency was zero, judgments themselves remained close to zero but were biased by the overall frequency with which the outcome occurred. In Experiment 2, it was shown that the growth function was not the result of the anchoring of early judgments at the zero point. The bias in judgments when the contingency is zero was investigated in Experiment 3. The results are discussed in terms of rule-based analyses and contemporary theories of conditioning.     

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.     

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.