Repetition priming with aspect and agreement morphology in American Sign Language

Two experiments are reported which investigate the organization and recognition of morphologically complex forms in American Sign Language (ASL) using a repetition priming technique. Three major questions were addressed: (1) Is morphological priming a modality-independent process? (2) Do the different properties of agreement and aspect morphology in ASL affect priming strength? (3) Does early language experience influence the pattern of morphological priming? Prime-target pairs (separated by 26–32 items) were presented to deaf subjects for lexical decision. Primes were inflected for either agreement (dual, reciprocal, multiple) or aspect (habitual, continual); targets were always the base form of the verb. Results of Experiment 1 indicated that subjects exposed to ASL in late childhood were not as sensitive to morphological complexity as native signers, but this result was not replicated in Experiment 2. Both experiments showed stronger facilitation with aspect morphology compared to agreement morphology. Repetition priming was not observed for nonsigns. The scope and structure of the morphological rules for ASL aspect and agreement are argued to explain the different patterns of morphological priming.     

Facilitating friendship formation in late life: Puzzles and challenges

Considerable evidence indicates that friendships contribute to the psychological well-being of older adults. Seeking ways to help lonely older adults form new friendships thus makes a good deal of sense, but as the disappointing results reported by Heller et al. (1991) indicate, translating this conceptually sound goal into a practical reality presents many challenges. This commentary seeks to build upon the authors' analysis of factors that may have undermined the success of their intervention by discussing the social contexts that may be most conducive to friendship formation in late life and by considering whether kin ties represent a more viable focus of intervention efforts than do peer ties.     

Differential rates of exhaustion and recovery of several parameters of male rat sexual behavior.

Sexual exhaustion of the male rat was studied with respect to several copulatory measures. The ejaculatory latency, intercopulatory interval, and intromission frequency demonstrate a U-shaped curve, exhibiting high values for the initial ejaculatory series, falling to a minimum at an intermediate ejaculatory series, and again increasing at exhaustion. The absolute refractory period of the postejaculatory interval (measured at vocalization termination) increases linerly, whereas the relative refractory period (the remaining portion of the postejaculatory interval) is a postively accelerating function. Partial recovery tests demonstrated that the preejaculatory measures and absolute refractory period have substantially returned to baseline values by Day 6, while the relative refractory period is still extended. The significance of these data to the theoretical modeling of sexual behavior is discussed.     

AN ANALYSIS OF MULTIPLE MISPLACED PARENTAL SOCIAL CONTINGENCIES1

This study analyzed the training of a mother to modify five subclasses of her attention to her young child's noncompliance with instructions, and also displayed the changes in her child's behavior correlated with these events. Training in four subclasses consisted of teaching the mother to withhold various forms of social attention to her daughter's undesired behavior; training in the fifth subclass involved introduction of a brief room-timeout procedure for noncompliance. The effectiveness of the parent-training procedure, consisting of initial instructions and daily feedback, was demonstrated through a multiple-baseline design across the five subclasses of parent behavior. Sequential decreases in the first three subclasses of the mother's social attention to undesired child behavior resulted in incomplete improvements in some child responses; however, a decrease in the fourth subclass resulted in a significant increase in undesired child behavior. Complete remediation of all child behaviors was achieved following the training of a timeout procedure for noncompliance. Postchecks conducted up to 16 weeks later showed that these effects were durable.     

Timeout duration and the suppression of deviant behavior in children

The effects of three different timeout durations were investigated in a group of 20 retarded, institutionalized subjects. Each subject received 1, 15, and 30 min of timeout in a design that was counterbalanced in terms of the order in which timeout durations were presented. Displays of deviant behavior-such as aggression, tantrums, and self-destruction-were followed by periods of isolation in a timeout room. A reversal design was employed such that return-to-baseline periods were instituted after each timeout period. The overall effect of timeout was to reduce significantly the rate of deviant behavior. On the average, 15 and 30 min produced a 35% decrease in deviant behavior with little difference between the effectiveness of 15 and 30 min. The range of effects in all timeout conditions varied widely. The sequence in which the 1-min duration was presented effected the direction of its effect. When it preceded the use of longer durations, 1 min was most effective. As it came later in the sequence, its suppressive characteristics became less reliable.     

A SIMULTANEOUS DISCRIMINATION PROCEDURE FOR THE MEASUREMENT OF VISION IN NONVERBAL CHILDREN1

Few nonverbal developmentally disabled children ever receive adequate vision assessment because of their limited language skills. The present study details a simultaneous discrimination procedure for measuring subjective visual acuity in such children. A stimulus fading procedure was used to train a discrimination between Snellen Es differing in orientation, and a psychophysical tracking method was used to determine acuity thresholds. The procedure was tested with 11 nonverbal autistic and schizophrenic children and validated with four nonpsychotic children. Eight of the psychotic children were successfully examined in one to three sessions. Two of these children were identified as having significant acuity losses. The validity assessment showed that the experimental procedure resulted in thresholds equal to or slightly lower than those obtained with the Illiterate E chart.