Response-contingent stimulation as a treatment for developmental failure in infancy

An 8-month-old infant with a developmental quotient of $\text{1}\text{1}\text{2}$ months was given response-contingent stimulation using a pressure-sensitive pillow which turned an overhead mobile. The subject learned to control the mobile by kicking the pillow, and concurrently began smiling at both the mobile and her mother for the first time. After mastering three contingencies on arm, head, and leg movement, she displayed what appeared to be a Piagetian coordinated secondary circular reaction, in which one response provided 4 seconds of access to another contingency. Although the subject remains severely retarded, the results suggest that some forms of developmental delay may be treated at least in part as a failure to develop contingency awareness.     

Duration estimates of two information processing components

Adult humans attempted to make quick responses to the first of two sequentially presented visual stimuli. At short interstimulus intervals (less than about 100 msec) accuracy was impaired by a different second stimulus and this was hypothesized to reflect the activity of an information processing component concerned with stimulus registration. At longer interstimulus intervals (up to approximately 350 msec) reaction time was inhibited by a different second stimulus and this was assumed to reflect the activity of a second component concerned with decision. The stimulus registration component was insensitive to variations in the complexity of the task, while the decision component was found to be greater for a task requiring recognition (is the current stimulus the same as an earlier one?) than for one merely requiring choice (what is the current stimulus?). This functional independence and the sizeable difference in the temporal range of susceptibility led to the conclusion that two distinct information processing components were involved.     

Perceived control in continuous loud noise

The effects of two types of perceived control were assessed for performance during and following exposure to continuous loud noise at 90 dBC. Subjects performed a tracking task during exposure and the Stroop test in the period following exposure. Control could be effected either (1) by attenuating the intensity of the noise or (2) by reducing the difficulty of the tracking task. In both cases subjects were encouraged not to exercise control. Performance in treatments involving loud (90 dBC) and soft (55 dBC) noise served as baseline conditions. Perceived control of task difficulty accentuated the tendency for root-mean-square error to rise during the tracking task. There were no significant effects of noise intensi ty on tracking performance. Loud noise reduced the incidence of errors in the Stroop test but perceived control failed to influence this effect. The results are discussed in terms of the generality of perceived control phenomena.     

Verbal ability and mental processing speed

The notion that verbal ability is related to mental processing speed was examined using tasks that systematically varied in semantic content. Subjects' reaction times were measured in five tasks involving arrow matching, physical identity word matching, or taxonomic identity word matching. The findings indicated that matching tasks using different decision rules and different stimuli were all related to verbal ability. In fact, reaction time for subjects required to judge whether two arrows pointed in the same direction was the best predictor of verbal ability. One explanation of the results is that speed of information processing (a general factor) may be the important component of verbal ability which is measured by seemingly different matching tasks.     

Discriminative infant smiling to orientations of talking faces of mother and stranger.

Thirty-two infants aged 14 and 20 weeks were presented with a live face in each of eight conditions, which consisted of all combinations of (a) a 0° or 90° orientation; (b) familiar face (the infant's mother) or distinctively unfamiliar face; and (c) talking or silent context. The previous findings that younger infants smile longer at 0° than at 90° faces and that this differential responsiveness to orientation wanes with increasing age were replicated; the hypothesis that older infants would smile longest at their mothers' talking faces in the 0° orientation was confirmed. In addition, infants of both ages smiled more at their mothers than at the stranger, although this effect interacted with orientation and sex of the infant.     

Reducing residential electrical energy use: payments, information, and feedback

Monetary payments, energy information, and daily feedback on consumption were employed to reduce electricity use in four units of a university student housing complex. A combined multiple-baseline and withdrawal design permitted both within- and between-unit comparisons. Payments produced immediate and substantial reductions in consumption in all units, even when the magnitude of the payments was reduced considerably. Feedback also produced reductions, but information about ways to conserve and about the cost of using various appliances did not. It was also found that, in general, payments combined with either information or feedback produced no greater effect than payments alone.     

Effects of schedule and magnitude of reinforcement under conditions of thirst motivation

In contrast to a recent finding (Macdonald, G. E., & De Toledo, L. Learning and Motivation, 1974, 5, 288–298.) the results of three experiments investigating various partial reinforcement (PRF) manipulations under conditions of thirst motivation demonstrated strong similarity to analogous manipulations involving food reward. Specifically, for animals receiving water reinforcement, PRF was shown to generate greater resistance to extinction than continuous reinforcement (Expt 1 & 3), the schedule of reinforcement was shown to interact with level of acquisition (Expt 1 and 2), and the magnitude of the partial reinforcement extinction effect was shown to be a function of reward magnitude (Expt 3). These results provide strong evidence that mechanisms which operate in partial reinforcement situations are highly similar, regardless of the type of appetitive reinforcement.     

Age-related differences in ambulatory blood pressure during daily stress: evidence for greater blood pressure reactivity with age

Prior research on age and emotions has found that older adults may show better physiological regulation to stressful stimuli than do younger adults. However, the stress reactivity literature has shown that age is associated with higher cardiovascular reactivity to laboratory stress (J. R. Jennings et al., 1997). The authors investigated these conflicting findings further by examining daily ambulatory blood pressure in 428 middle-aged to older adults. Consistent with the age and reactivity literature, relatively old individuals showed significantly greater increases in ambulatory diastolic blood pressure compared with younger individuals when dealing with daily stressors. However, results also revealed that relatively old individuals reported less of an increase in negative affect during daily stress compared with their younger counterparts. The results of this study are consistent with the age-related increase in cardiovascular risk but highlight the complex links between stress and different facets of the aging process.     

Life before and after quitting smoking: an electronic diary study

This article describes a multidimensional, multivariate, and multilevel approach to the assessment of nicotine withdrawal. In this prospective study, 70 adult smokers assigned to an active or placebo nicotine patch condition completed multiple daily assessments using an electronic diary. Average and individual growth curves were estimated for affective and nonaffective withdrawal symptoms. All symptoms but hunger increased significantly on the quit day and remained elevated for three weeks. Variability in symptom experiences across individuals increased from pre- to post-quit. Relations between symptom reports (e.g., negative affect or craving) and episodic events (e.g., stressful events or seeing someone smoke) changed from pre-quit to post-quit. Pre-quit increases in negative affect and quit-day increases in craving were inversely related to abstinence three months after the quit day, suggesting that anticipatory and immediate reactions to quitting influence success.     

The influence of augmented feedback and prior learning on the acquisition of a new bimanual coordination pattern

The present research examined two variables regarding the acquisition of a new bimanual coordination pattern: the role of previous experience and the nature of augmented feedback. Two groups of participants acquired a new coordination pattern (135 degrees relative phase) following two sessions of practice of another novel pattern (90 degrees relative phase). Transfer of learning in these groups was compared to two groups that had not previously learned a new pattern, but were nevertheless influenced by coordination patterns that are intrinsic to the task of bimanual relative timing (in-phase, 0 degrees, and anti-phase, 180 degrees). The findings revealed that new learning overshadowed the influence of the intrinsic patterns. Learning was also greatly affected by augmented feedback: dynamic, on-line pursuit tracking information was more effective in transfer than static, terminal feedback. Implications of these findings regarding theoretical constructs in motor learning are discussed.