TEMPORAL CONTROL ON INTERVAL SCHEDULES: WHAT DETERMINES THE POSTREINFORCEMENT PAUSE?

On fixed-interval or response-initiated delay schedules of reinforcement, the average pause following food presentation is proportional to the interfood interval. Moreover, when a number of intervals of different durations occur in a programmed cyclic series, postreinforcement pauses track the changes in interval value. What controls the duration of postreinforcement pauses under these conditions? Staddon, Wynne, and Higa (1991), in their linear waiting model, propose control by the preceding interfood interval. Another possibility is that delay to reinforcement, signaled by a key peck and/or stimulus change, determines the subsequent pause. The experiments reported here examined the role of these two possible time markers by studying the performance of pigeons under a chained cyclic fixed-interval procedure. The data support the linear waiting model, but suggest that more than the immediately preceding interfood interval plays a role in temporal control.     

Why Religion Should Be an Integral Part of Public School Education

Studies of classroom climates completed in the 1980s concluded that religion, even broadly defined, is seldom discussed in public schools. This situation is inconsistent with important precedents of our society, and therefore, public schools ought rightly to provide opportunities for students to discuss religion, broadly defined, in a scholarly fashion throughout their normal school routine. This article delineates 10 logical and cultural underpinnings for religious instruction in public schools.     

Health behavior, knowledge and attitudes among Swedish university students

A range of health behaviors was related to beliefs concerning health practices and health knowledge. A questionnaire dealing with health-related practices, health beliefs and knowledge of health risk factors was answered by 166 male and 179 female students aged 18–30 years at Stockholm University. Female students reported engaging in better health behavior than males. Beliefs about the importance of health behaviors were closely related to their frequency of occurrence. There was only a weak relationship between health behaviors and knowledge of specific health matters. It is concluded that health attitudes rather than health knowledge determine health behavior.     

Psychological well-being and homemaker vs. retiree identity among older women

Social roles have been a central focus in both sociological and developmental theories of adjustment in late life. Research on roles and well-being, however, has focused on earlier adulthood or on comparisons of tenuous roles (such as retiree) with institutional roles (such as employee), especially among men. The few studies comparing older women in the tenuous roles of homemaker and retiree all compare single-role women, and show contradictory results. One possibility is that multiple role identities are linked to greater well-being in older women, as they are among younger women. In this paper the life satisfaction, depression, and self-esteem of older women who consider themselves retired only, homemakers only, or both are compared. The sample includes 864 Black (N=242) and White (N=622) women ages 60 and over from a 1986 national survey. Retired women and homemakers did not differ in well-being; women who called themselves both had higher self-esteem and lower depression than single-role women. In analyses exploring what tenuous role content (daily activities) might explain group differences in well-being, do-it-yourself activities and volunteer activities were significant. Age, education, health, and marital status were also important factors. Recommendations include adopting a multiple role perspective with older women and encouraging their participation in instrumental, informal role activities to maximize well-being.Northwestern University     

The stability of individual differences in gender typing: Implications for understanding gender segregation

The stability of individual differences has important implications for understanding the origins of gender-typed behaviors. For example, if some children have a stronger preference for same-sex playmates (gender segregation) than do others, then exploring characteristics that may differentiate these children from their peers (e.g., preference for gender-typed toys or teacher proximity) should prove fruitful. Otherwise, research might be focused more appropriately on group-level processes or situational factors rather than individual differences. In the current study, 57 2 1/2- to 3-year-olds from middle-class Canadian homes were observed repeatedly during free play at their preschools. Four aspects of gender typing (gender segregation, use of masculine and feminine gender-typed toys, teacher proximity) were measured so that the stability of individual differences and relations among the measures could be assessed. Stable individual differences were found for all four measures among boys, and for two of the measures (feminine toy play, teacher proximity) among girls. In addition, boys who played most frequently with masculine toys rarely were observed in proximity to the teacher. However, there was no relation between gender segregation and the other indices of gender typing.     

A neural-network model enabling sensorimotor learning: Application to the control of arm movements and some implications for speech-motor control and stuttering

Summary Low-level motor control is defined as adapting an organism to the unique physical properties of its own limbs. The two-jointed arm serves to exemplify that effective low-level motor control demands a neurally mediated inversion of the dynamics, as well as of the kinematics, of a limb system. Reflex-like processing — that is, feedforword of either actual or predicted proprioceptive signals —is thereby assumed to be the principle of the dynamics control. As regards speech-motor control, the overall tool transformation is assumed to transform the force pattern of the articulatory muscles into speech sounds. Like the arm model, the vocal-tract transformation thus defined is also divided into two parts, namely the transformation relating the muscle forces to the mechanospatial states of the vocal tract (which is analogous to the forward dynamics including natural interarticulatory couplings), and the transformation relating the mechanospatial states to the speech sounds. Low-level speech-motor control, then, needs to invert both transformations, each of which can be learned by means of the self-imitation algorithm. Erroneous learning can fail to decouple interarticulatory coupling and therefore lead to abnormal feedback loops through the reflex-like operating neural network, which in turn can cause stuttering if audiophonatoric coupling is involved in learning.     

Auditory accessory effects on visual processing

A series of experiments on intersensory facilitation demonstrates that non-informative sound of low to moderate intensity (30/80 dB) facilitates the reaction to a visual stimulus. By manipulating the preprocessing and perceptual stages of the visual signals, it appears that auditory intensity reduces choice reaction time independently from the positive influence of the intensity and duration of the visual imperative signal, but interacts with the effect of stimulus degradation. Degraded stimuli take more profit of the sound than intact stimuli. Besides a short-term activation effect, originated by accessories of the auditory modality, on the motor adjustment stage (cf. Sanders 1983), the results suggest that the accessory influences the stage of feature extraction.     

Parenting attitudes of adolescent and older mothers

The parenting attitudes of adolescent and older mothers were assessed at 1 and 12 months postpartum to explore group differences and determine if these attitudes predicted quality of home environment and parenting behaviors at 12 months. Adolescent mothers scored significantly lower than did older mothers in empathy toward children's needs, but there were no significant group differences on three other parenting attitude constructs. There were no significant correlations between parenting attitudes at 1 month and parenting behaviors at 12 months for either group. For adolescent mothers at 12 months postpartum, the only attitude construct that was significantly related to concurrent quality of parenting was developmental expectations of the child. These and other findings are discussed in the context of current theory and intervention related to adolescent parenting.     

Structured role assignment and other techniques for facilitating process in adolescent psychotherapy groups

The application of various types of techniques for structuring the interchange and feedback process in adolescent psychotherapy groups is described. Techniques include random assignment of "roles" for each member during sessions, "parent hot seat" exercises, group goal booklets, and negotiation exercises. These have proved helpful in ensuring effective group participation, providing practice in social skills and verbalization of feelings, and in the development of other specific mastery skills.