The influence of instructive feedback presentation schedule: A replication with children with autism spectrum disorder

Instructive feedback (IF) is a modification to discrete trial instruction that may increase instructional efficiency for individuals with autism spectrum disorder. Several variations of IF have recently been evaluated in the literature; however, few studies have assessed the effectiveness and efficiency of presenting secondary targets on continuous versus intermittent presentation schedules. The current study evaluated the effectiveness and efficiency of various presentation schedules of secondary targets during discrete trial instruction. Specifically, we replicated and extended Griffen et al. (1998) by comparing a condition in which secondary targets were presented during each trial of a session, a condition in which secondary targets were presented every other trial, and a condition in which secondary targets were presented about every 4 trials. Within-subject replications were included for both participants. One of the intermittent presentation schedules was associated with the most optimal outcomes in all 4 comparisons.     

A comparison of stimulus set size on tact training for children with autism spectrum disorder

Previous studies on skill acquisition have taught targets in stimulus sets composed of different numbers of stimuli. Although the rationale for selection of a stimulus set size is not clear, the number of target stimuli trained within a set is a treatment decision for which there is limited empirical support. The current investigation compared the efficiency of tact training in 4 stimulus set sizes, each of which included 12 stimuli grouped into (a) 4 sets of 3 stimuli, (b) 3 sets of 4 stimuli, (c) 2 sets of 6 stimuli, and (d) 1 set of 12 stimuli. Results of all 4 participants with autism spectrum disorder show tact training with larger (i.e., 6 and 12) stimulus set sizes was more efficient than training with smaller (i.e., 3 and 4) stimulus set sizes.     

Genotype and environment in the social interactions of wild and domestic “Norway” rats

Wild rats, Rattus norvegicus, (a) trapped as adults or (b) of the second generation in captivity (lab-wild), and domestic rats of two strains, were studied for 28 days in artificial colonies in large cages with attached nest boxes. Controls were kept in mated pairs in small cages. Each colony consisted of six males and six females. The interactions of the males in six colonies of trapped rats were highly “stressful;” 61% died; and most of the survivors lost weight and had greatly enlarged adrenals. In each colony, however, there was a male (an alpha) that gained in weight and spent much time, during the dark hours, in the open on the floor of the cage; and in three colonies there were also other males (“betas”) that gained in weight. The adrenals of alphas and betas weighed about the same as those of the controls. In one of the 12 colonies of domestic rats one male behaved like a wild male; but in the other colonies the males gained in body weight and their adrenal weights resembled those of the controls. In three colonies of lab-wild rats 22% of the males died, but there was no evidence of males of different status. The findings confirm that the “agonistic” behavior of domestic rats is usually much attenuated in comparison with that of the wild type; a number of methodologic implications are discussed.     

Further experiments on the social interactions of domestic “Norway” rats

Domestic rats, Rattus norvegicus, aged nearly one year, were studied in artificial colonies in large cages with attached nest boxes. As in previous experiments on younger domestic rats, but not those on wild rats, the colonies were peaceful. Questions concerning the “aggressive” or “agonistic” behavior of domestic rats are further discussed.     

The direction of masked auditory category priming correlates with participants' prime discrimination ability

Semantic priming refers to the phenomenon that participants typically respond faster to targets following semantically related primes as compared to semantically unrelated primes. In contrast, Wentura and Frings (2005) found a negatively signed priming effect (i.e., faster responses to semantically unrelated as compared to semantically related targets) when they used (a) a special masking technique for the primes and (b) categorically related prime-target-pairs (e.g., fruit-apple). The negatively signed priming effect was most pronounced for participants with random prime discrimination performance, whereas participants with high prime discrimination performance showed a positive effect. In the present study we analyzed the after-effects of masked category primes in audition. A comparable pattern of results as in the visual modality emerged: The poorer the individual prime discrimination, the more negative is the semantic priming effect. This result is interpreted as evidence for a common mechanism causing the semantic priming effect in vision as well as in audition instead of a perceptual mechanism only working in the visual domain.     

Dissociation of Bimanual Responses With the Simon Effect: On the Nonunitization of Bimanual Responses

The authors examined whether responses of the 2 hands were completely unitized when participants (N = 36) produced bimanual responses to lateralized targets in a Simon-type paradigm. Their primary aim was to investigate whether lateralized stimuli differentially influence the response dynamics of the 2 hands. Simon effects were obtained in reaction time and force; components of the bimanual response by the hand on the same side as the lateralized stimulus were more forceful than were those of the other hand. Also, Simon effects were larger when the lateralized target appeared alone than when it was accompanied by a distractor on the other side of the display. Finally, responses of the 2 hands were correlated most strongly when stimulus displays were symmetrical. The authors conclude that bimanual responses are strongly coupled, but not perfectly so.     

Aggressive and affiliative behavior in green monkeys with differing housing complexity

Eleven green monkeys (Cercopithecus aethiops) were combined into three social groups (two heterosexual, one all-male) in enclosures with similar volume but different levels of environmental complexity (two or four compartments). Agonistic and affiliative interactions were recorded over a 21-week period. The two heterosexual groups had their environmental complexity reduced (number of compartments reduced by one-half and volume/floorspace reduced by one-third) for a 5-week period in the middle of the study. Rates of contact aggression were low throughout the study. In the group with complexity reduced to one compartment, rates of noncontact aggression and affiliative behavior increased, and remained high after complexity was restored. In the group reduced to two compartments, rates of affiliative behavior increased but rates of noncontact aggression decreased, trends which continued after complexity was restored. The all-male group exhibited low rates of affiliative behavior throughout. Two compartments appear to foster successful group formation, but any change in a group's enclosure can have long-term effects on rates of aggression. © 1992 Wiley-Liss, Inc.     

The influence of the Y-chromosome of Rb/1Bg mice on agonistic behaviors

Males of the Rb/lBg and C57BL/10Bg strains, as well as of the Bl0RblF, and RblBlOF1, reciprocal hybrids, were tested for aggression over three daily trials beginning at 50 days of age. The BlORblF, hybrids were sired by Rb/lBg males, and the RblBlOF, hybrids were sired by C57BL/10Bg males. The mean scores for the agonistic acts of chase, wrestle, flank-bite (but not tail rattle or attack), and the mean “aggression” score (but not mean latencies to first agonistic act or first attack) were significantly higher for BlORblF, than for RblBlOF, hybrids. These findings are consistent with the hypothesis that some aspect(s) of the Rb/lBg Y-chromosome strain can influence the occurrence of some of the motor patterns of offense but not defense. The Y-chromosomes of the DBA/1, DBA/2, CBA, and PHH inbred strains have a similar effect on agonistic behaviors.