The effect of auditory input on cerebral laterality

Cerebral laterality was examined for third-, fourth-, and fifth-grade deaf and hearing subjects. The experimental task involved the processing of word and picture stimuli presented singly to the right and left visual hemifields. The analyses indicated the deaf children were faster than the hearing children in overall processing efficiency, and that they performed differently in regard to hemispheric lateralization. The deaf children processed the stimuli more efficiently in the right hemisphere, while the hearing children demonstrated a left-hemisphere proficiency. This finding is discussed in terms of the hypothesis that cerebral lateralization is influenced by auditory processing.     

Letter familiarity does not aid feature extraction

Summary Familiarity effects in visual letter processing were examined by means of a mutilation detection task. The uppercase E was used as the non-mutilated letter. One or two horizontal bars of the E were delected, to produce an upright or inverted F or L. These four mutilations of the E were assigned to the same response. In Experiment 1, brief exposure of the stimuli was followed by a backward mask. Experiment 2 was identical to Experiment 1, except that the display duration of the stimulus was increased and the backward mask was omitted. In Experiment 3, the overall luminance of the stimuli (luminance per point times length of the constituent line segments) was held constant. In Experiment 4, the upright and inverted non-E letter occurred in different blocks to encourage a normal (upright) letter processing strategy in the upright letter blocks. Accuracy (Experiment 1) and mean correct response times (all experiments) were not different for the upright and inverted F or for the upright and inverted L. These findings and converging results from other studies indicate that the higher familiarity of the upright letters did not aid feature extraction.     

A bayesian approach to confirmatory factor analysis

Confirmatory factor analysis is considered from a Bayesian viewpoint, in which prior information on parameter is incorporated in the analysis. An iterative algorithm is developed to obtain the Bayes estimates. A numerical example based on longitudinal data is presented. A simulation study is designed to compare the Bayesian approach with the maximum likelihood method.Computer facilities were provided by the Computer Services Center, The Chinese University of Hong Kong.     

The effects of reward on tutor's behaviors in a cross-age tutoring context

Utilizing a cross-age tutoring context, this study examined the effects of reward on the teaching behaviors of the tutor, the tutor's subsequent motivation to continue to teach during a free choice period, and the social interaction between a tutor and a tutee. Third-grade boys and girls (n = 96) who exhibited a positive reinforcement style were asked to teach six addition problems to a first-grade boy or girl (n = 96). The children were randomly assigned to pairs and to one of the three reward conditions. In the performance-contingent reward condition, the tutors were promised a toy if the first-grader learned all of the arithmetic problems. In the noncontingent reward condition, the tutors were promised a toy for teaching the first-grader. In the no reward condition, the tutors taught the first-grader without promise of a toy. The results indicated that the social interaction was rated lower for the children in the performance-contingent group and that the tutors in this group spent less time teaching during the free choice period. However, neither the tutor's teaching style nor the tutee's post-test performance was adversely affected by the reward.     

Pavlovian processes do mediate control of the “advance” response strategy

Two parallel experiments used pigeons in a transfer of control design to determine the basis of the transfer of the use of the “advance strategy” across successive discriminations (W. K. Honig & H. Lindsay, Learning and Motivation, 1975, 6, 157–178). Pigeons were first trained under instrumental contingencies to use an “advance” response to maximize their exposure to S^D and minimize their exposure to S^Δ. Then orthogonal stimuli (key lights in Experiment 1 and diffuse illuminations in Experiment 2) were independently established through separate discriminative Pavlovian procedures as CS+ and CS? or as CS^o's. Later in special tests, it was demonstrated that the associative values of the Pavlovian CS's were a major factor governing the use of the advance strategy: only pigeons exposed to $\text{CS+}\text{CS?}$ used the advance response to regulate their exposure to either CS. Although these experiments showed that the necessary and sufficient conditions for utilization of the advance strategy are the Pavlovian associative values of the discriminative stimuli, opportunity for differential “operant” responding during the discriminative stimuli seems to be a contributor to the optimal use of the advance response across successive discriminations.     

Two logit models for external analysis of preferences

A logit vector model and a logit ideal point model are presented for external analysis of paired comparison preference judgments aggregated over a homogeneous group. The logit vector model is hierarchically nested within the logit ideal point model so that statistical tests are available to distinguish between these two models. Generalized least squares estimation procedures are developed to account for heteroscedastic sampling error variances and specification error variances. Two numerical illustrations deal with judgments concerning employee compensation plans and preferences for salt and sugar in the brine of canned green beans.     

Marital disturbance and child problems: A cautionary note regarding hyperactive children

In previous work, investigators have found a relationship between marital discord and childhood conduct problems (aggression) in clinic samples. Given the wide variability of aggression found among hyperactive children,it would follow from previous work that child aggression may be associated with marital discord in a hyperactive population. This hypothesis was tested in a sample of 23 boys (ages 5 to 8) diagnosed as attention deficit with hyperactivity. Aggressive behaviors were tracked by the children's teachers for 12 school days. Parental and teacher ratings of conduct problems were also obtained. Additionally, the auditory version of the laboratory Continuous Performance Test was administered. Marital adjustment, overt hostility, and conflict tactics, as reported by the mothers, were not significantly correlated with any of the measures of aggression or conduct problems. In other words, marital discord in families with a hyperactive boy did not explain differential rates of aggressive behavior despite definite variability in both the marital and child behavioral measures. Marital discord was marginally related to severity of attentional deficit on the Continuous Performance Test. The results underscore the need for caution in attempting to extend findings from a general population (i.e., undifferentiated clinicreferred children) to a specific diagnostic subgroup (i.e., attention-deficit hyperactive children).