A new measure for determining children's subjective organization of speech

A new technique for determining children's subjective organization of speech is described. The technique consists of teaching a child a sentence and then repeatedly (1) reading the sentence up to a selected point, (2) sounding a tone, and (3) having the child supply the next word. The time from the tone to the onset of the child's voice is the dependent variable. In the first study 6- and 8-year-old children memorized the following sentence: “John likes to feed the little puppies in the barn.” Their response times suggested that the dominant segmentation pattern consisted of four phrases: a subject phrase, a verb phrase, an object phrase and a modifier phrase. Within each phrase differences between reaction times were on the order of 30 msec. Across phrases they were on the order of 120 msec. The same trend emerged for subsamples of the children with various short-term memory sizes, and for adults. It also appeared for subsamples of the total scores (e.g., first six trials and last six trials). In order to provide further evidence of the technique's validity, different sentences of the same general type were presented to children with short-term memory spans of either 3, 4, or 5. As predicted, it was found that when children's spans corresponded to the number of hypothesized chunks (i.e., 4), they could repeat the sentences verbatim on the first exposure. They could not do so, however, when their spans were lower than that value or when the number of phrases was increased. It was concluded that the new technique is a promising one for assessing young children's patterns of speech segmentation.     

Satiation for social reinforcers: The effects of contingency,vicarious experience,and ambiguous situations

The relative satiation effect, an inverse relationship between the frequency of prior social reinforcement (the word “good”) and the later effectiveness of the social reinforcer in controlling behavior, was studied. In Experiment 1, a discrimination task in which social reinforcement was given for correct responses was administered to first- to fourth-grade children (6 to 10 years of age), who had during a preexposure phase performed a preliminary task or observed another child performing. During the preexposure phase, the experimenter delivered frequent or infrequent social reinforcement that was either contingent or noncontingent. Only performers and observers who had experienced frequent noncontingent reinforcement showed the satiation effect during the discrimination task phase. The results were interpreted as inconsistent with J. L. Gewirtz' (Developmental Psychology, 1969, 1, 2–13) social drive formulation but supportive of an informational analysis in which the children are seen as responding appropriately to unambiguous evidence concerning the reliability of contingency information. In Experiment 2, seating arrangements were varied so that information concerning the direction of reinforcement was made ambiguous. Performers were less responsive during the discrimination phase after experiencing frequent noncontingent reinforcement when seated alone or opposite an observer than when seated next to an observer. The results are interpreted as indicating trust of the reliability of the contingency under ambiguous conditions.     

Meditation,personality and arousal

A questionnaire survey of people who had learned a technique of meditation was carried out to assess persistence with practice, perceived effects of meditation practice and subjective experiences during meditation. The results suggested that a significant proportion give up meditating (42.9%) and that the subjective experience of meditation was similar to that of the hypnagogic state. Reported effects of meditation were generally physiological and psychological benefits related to relaxation.A personality questionnaire was also distributed and the results suggested that those attracted to meditation are significantly more neurotic and introverted than the general population but that those who continue with meditation are significantly less neurotic than those who give up their practice.These findings are discussed in terms of regression effects and in relation to a theory of personality and arousal.     

Effects of neutral and positive stimuli on stuttering: “Calling attention to stuttering” revisited

This study investigated the effects of presumably positive and neutral response-contingent stimuli on the occurence of stuttering. Eight adult stutterers spoke spontaneously during a 60-min experimental session, which was divided into three 20-min periods. During Condition I no stimuli were delivered. During Condition II a digital counter and a pair of yellow lights were activated each time the subject stuttered. During Condition III these same response-contingent stimuli were delivered, but with the additional factor that the subject would earn 5¢ each time the counter moved forward and the lights were illuminated. Conditions II and III were counterbalanced across subjects. The experimenter was unaware of which of the two contingencies were operative during Conditions II and III. Results showed no significant changes in occurence of stuttering due to either response-contingent stimulus. A discussion of theoretical and experimental implications is given.     

Statistical significance tests for binormal ROC curves

Statistical significance tests are derived and evaluated for measuring apparent differences between an obtained and an expected binormal ROC curve, between two independent binormal ROC curves, and among groups of independent binormal ROC curves. A binormal ROC curve is described by two parameters which represent the spread of the means and the ratio of the standard deviations of the two underlying Gaussian decision variable distributions. To test the significance of apparent differences between or among ROC curves, approximate χ² statistics for each of the three tests were constructed from maximum likelihood estimates of the two parameters defining the binormal ROC curve. The performance of each test statistic was evaluated by simulating five-category rating scale data with equal numbers of noise and signal-plus-noise trials (set at 50, 250, and 500) for each of three typical ROC curves. For the significance test involving only one ROC curve, rating scale data were generated from the chance diagonal of the ROC space also. Although test performance was found to be somewhat dependent on the number of trials and on the location of the ROC curve in the ROC space, comparisons of the obtained and expected fractions of (falsely) significant results at various α levels showed the proposed statistical significance tests to be reliable under practical experimental conditions.     

Some effects of lick-contingent delays on the development of schedule-induced polydipsia

Experiments 1 and 2 examined the effects of various durations of lickcontingent delays of reinforcement on the development of schedule-induced polydipsia. Food was provided every 1 min in the absence of licking. Delays of 1 min or more effectively disrupted the development of the licking behavior. In Experiments 3 and 4 a lick-contingent stimulus was provided in addition to the delay of food delivery. A light, which was turned on by a lick and turned off by food, greatly enhanced the development of polydipsia under delays that had previously prevented such development. A tone proved less effective than the light in promoting the development of polydipsia. Adventitious reinforcement and conditioned punishment explanations of these results were considered. A distinction was drawn between the mechanism responsible for the development of schedule-induced behavior and that responsible for its maintenance.     

The effects of Familial Sinistrality and preferred hand on dichaptic and dichotic tasks

Processing asymmetries for tactile-spatial and auditory-verbal processing were investigated in two studies using the S. F. Witelson (1974, Cortex, 10, 3–17) dichaptic procedure. Experiment 1 used eight right-handed males in a free recall procedure. More shapes were correctly detected by the left hand but only with a right hand response. In Experiment 2, right and left handers with no Familial Sinistrality (FS) were compared with left handers with various types of FS, looking at pre- and postcued order of report and precuing the response hand. No group showed hand asymmetry with pre- or postcuing for either responding hand. Right handers showed no difference with order of report; however, left handers made fewer correct detections for items to be reported second. There were differences between the Parental FS and the Sibling FS groups both on the dichotic listening and the haptic tasks.