The Organization of Extrinsic Neurons and Their Implications in the Functional Roles of the Mushroom Bodies in Drosophila melanogaster Meigen

Although the importance of the Drosophila mushroom body in olfactory learning and memory has been stressed, virtually nothing is known about the brain regions to which it is connected. Using Golgi and GAL4–UAS techniques, we performed the first systematic attempt to reveal the anatomy of its extrinsic neurons. A novel presynaptic reporter construct, UAS-neuronal synaptobrevin–green fluorescent protein (n-syb–GFP), was used to reveal the direction of information in the GAL4-labeled neurons. Our results showed that the main target of the output neurons from the mushroom body lobes is the anterior part of the inferior medial, superior medial, and superior lateral protocerebrum. The lobes also receive afferents from these neuropils. The lack of major output projections directly to the deutocerebrum’s premotor pathways discourages the view that the role of the mushroom body may be that of an immediate modifier of behavior. Our data, as well as a critical evaluation of the literature, suggest that the mushroom body may not by itself be a “center” for learning and memory, but that it can equally be considered as a preprocessor of olfactory signals en route to “higher” protocerebral regions.     

A comparison of female supervisors in business and government organizations

This exploratory study compared the life style and interpersonal need orientation, leadership style, and perception of the organization structure of female supervisors in business and government organizations. The government group had a significantly higher formalistic and lower sociocentric and personalistic life style orientation; lower needs for expressed control, expressed affection, wanted inclusion, wanted affection, and a higher need for wanted control; were lower on consideration and higher on structure leadership dimensions; and perceived their organization as being more bureaucratic and less collaborative and coordinative than the business group. The findings were discussed in terms of the processes of individual-organization congruity and organizational socialization.     

Time error in lifted weights as affected by presentation order and judgment mode

In the method of constant stimulus differences, results obtained under two presentation orders (standard first and standard second) are commonly combined to eliminate time error. The present study shows that this technique is not adequate for controlling time error as the presentation orders have differential effects upon PSE. Using a two-handed technique, 96 subjects judged lifted weights on the comparative rating scale. The subjects lifted the standard before, with, or after the variable stimulus. They also either judged the standard in terms of the variable or the variable in terms of the standard (mode of judgment). Judgment mode, a previously uninvestigated confounding variable of presentation order was not an important factor in influencing the value of the PSE.     

The effects of study questions and grades on student test performance in a college course

Two experiments demonstrated the effects of study questions on student test performance in an introductory college course. Students in both experiments correctly answered study question items 20 to 30% more frequently than non-study question probes. Furthermore, mean performance on study question items was better than 90% during all phases of both experiments. The present experiments were also designed to study the effects of grades on test performance, and the relationship between long and short sets of study questions. The results of Experiment I clearly illustrated the importance of using grades to maintain high levels of student test performance. The results of Experiment II suggested that long sets of study questions may produce better performance on probe items than do short sets of study questions, but the effect was small.     

The modification of sentence structure and its relationship to subjective judgements of creativity in writing

The present study objectively defined and manipulated some compositional variables in 10-sentence stories written by fourth-, fifth-, and sixth-grade students, and related these operationally defined variables to subjective judgements of creativity. Points, exchangeable for candy and extra recess, were given to members of two teams contingent upon their using different adjectives, different action verbs, and different sentence beginnings. The students' use of these selected parts of speech was modified and the independent subjective ratings indicated that stories written during contingency conditions were generally rated as more creative than those written during baseline conditions. Operational definitions that specify non-repetition or variety of responses, and contingencies that require response diversity may provide a beginning basis for defining writing creativity and the conditions that maximize its occurrence.     

The effects of reinforcement on the modification, maintenance, and generalization of social responses of mental patients

Social greeting responses of three withdrawn, chronic schizophrenics were experimentally modified. Initially, none of the subjects spoke to an experimenter. Prompts and cigarette reinforcement were employed to produce increases in the rates of greetings. Then, the prompts were faded so that the greetings came under the control of the presence of the experimenter. Reversal and subsequent reinforcement procedures were employed to demonstrate that the responses were controlled by their consequences. Next, the schedule of cigarette reinforcement was leaned out so that greetings continued to occur in the absence of cigarette reinforcement. However, low or zero rates of greetings occurred in the presence of a second experimenter. Five new experimenters employed the prompting, fading, reinforcement, and schedule-leaning procedures. Subsequently, all subjects emitted appropriately high rates of greetings in the presence of the second experimenter. Without further application of the experimental procedures, greetings were still occurring in the presence of both the first and second experimenters almost three months later.     

Effects of candy and social reinforcement, instructions, and reinforcement schedule leaning on the modification and maintenance of smiling

Two retarded boys exhibited abnormally low rates of smiling. In Exp. I, the frequency of a boy's smiling was first increased with candy reinforcement, but the frequency of the response did not decrease when candy reinforcement was terminated. When the subject wore a sign designed to make social interactions contingent on not-smiling, the frequency of smiling decreased. The sign was then changed to make social interactions contingent on smiling and the rate of smiling increased. In Exp. II, a second boy initially never smiled. Establishment of a contingency for candy reinforcement did not increase this zero response rate. Instructing the child to smile initially increased smiling, but the instructions then became progressively more ineffective. Candy reinforcement increased the rate of smiling to a normal range, but the rate of the response promptly decreased when this reinforcement was discontinued. Continuous candy reinforcement was again employed to increase the response rate and then progressively leaner schedules of variable-ratio candy reinforcement were employed. Consequently, the rate of smiling did not decrease when candy reinforcement was again eliminated. Subsequently, signs were employed to regulate social interactions and the rate of smiling was shown to be controlled by these interactions serving as reinforcers.     

Rare targets are less susceptible to attention capture once detection has begun

Rare or low probability targets are detected more slowly and/ or less accurately than higher probability counterparts. Various proposals have implicated perceptual and response-based processes in this deficit. Recent evidence, however, suggests that it is attentional in nature, with low probability targets requiring more attentional resources than high probability ones to detect. This difference in attentional requirements, in turn, suggests the possibility that low and high probability targets may have different susceptibilities to attention capture, which is also known to be resource-dependent. Supporting this hypothesis, we found that, once attentional resources have begun to be engaged by detection processes, low, but not high, probability targets have a reduced susceptibility to capture. Our findings speak to several issues. First, they indicate that the likelihood of attention capture occurring when a given task-relevant stimulus is being processed is dependent, to some extent, on how said stimulus is represented within mental task sets. Second, they provide added support for the idea that the behavioural deficit associated with low probability targets is attention-based. Finally, the current data point to reduced top-down biasing of target templates as a likely mechanism underlying the attentional locus of the deficit in question.