Visual slow brain potentials in children with attention deficit disorder

Using a two-stimulus reaction time paradigm, with two separate reward conditions (contingent and noncontingent), we compared slow wave brain potentials (ERPs) in 144 children with attention deficit disorder (ADD) and 30 normal control children. This article reviews the findings during the 900 msec visual warning stimulus. As we had expected, based on ERP work of Forth and Hare (1989) and Raine, Venables and Williams (1990), and on previous work from our own laboratory, the group differences were found in the negative slow wave portions of the ERP complex during the contingent reward condition but not during the noncontingent condition. Aggressive hyperactive subjects with attention deficit disorder (ADDHA) were discriminated from nonaggressive subjects (including control subjects) during the contingent reward condition in the following ways: (1) greater fronto-central negativity (640–900 msec slow wave) and (2) greater right parietal than left parietal negativity (430–750 msec slow wave). All ADD subgroups, when compared to control (CONTR) subjects, showed greater slow wave negativity (700–900 msec) at the midline occipital electrode site during the contingent reward condition. This could be explained in part as an IQ effect on ERPs reflecting the IQ difference between the ADD subgroups and the controls. These slow wave findings seem to relate to attentional problems of these children. They are discussed in terms of a psychobiological model of inhibition/disinhibition and appetitive activation.     

Embedding instructive feedback into teacher-student interactions during independent seat work

The effects of embedding a constant time delay procedure into an independent seat work activity and using instructive feedback were evaluated in this study. Seven students with mild disabilities participated in the study that occurred in their special education classroom. A multiple probe design across sets of target behaviors was used, and students' responses to instructive feedback stimuli were evaluated during each probe condition. The procedures were implemented with a high degree of fidelity, and the results indicate that (a) the students acquired the target behaviors taught with the constant time delay procedure that was embedded into independent seat work, and (b) the students acquired some but not all of the responses to the instructive feedback stimuli. These findings are discussed in terms of using instructive feedback in classrooms and future research on instructive feedback.     

Lightness contrast in CRT and paper-and-illuminant displays

The increased use of CRT monitors for displaying and controlling stimuli in studies of surface color poses problems of comparability with data obtained with traditional paper-and-illuminant methods. A review of comparable studies using the two methodologies revealed that CRT studies tend to report larger contrast effects. To investigate factors that may be responsible for this difference, simultaneous lightness contrast was measured using both CRT and paper-and-illuminant presentations. The spatial distribution of luminance in the whole field of view and the visual angles subtended by the displays were controlled. The CRT presentation yielded contrast effects twice as big as those measured for a paper surface in a homogeneously illuminated room. However, a paper display under Gelb lighting yielded almost exactly the same effect size as that measured in the CRT presentation. These results demonstrate that contrast effects in both modes of presentation are affected by the spatial distribution of luminance beyond the basic experimental stimuli.     

On the examination of the role of the episcopalian priest in the pastoral ministry

The purpose of the research was to identify empirically and measurably those dimensions considered important by laity in evaluating their priest. The 83-item questionnaire was developed from existing instruments and from an interview survey carried out on laity from a national selection of Episcopal parishes. 221 parishes responded with complete data. A factor analysis was performed on the data yielding eight useable factors: (a) Pastoral sensitivity, (b) Administrative Skills, (c) Scholarship, (d) Personal Integrity, (e) Innovation, (f) Personal Spirituality, (g) Meaningfulness of Services, and (h) Laity Involvement. The results of the research were seen as a beginning insight into what the laity perceived as important aspects of their parish priest's role, and an instrument to measure these dimensions for further research was produced.     

Parallel between antianxiety and cardiovascular effects of chlordiazepoxide in genetically nervous dogs

There is evidence that cardiac arrhythmias are partially of CNS origin, and that certain drugs affect arrhythmia, both positively and negatively, through CNS action. We hypothesized and confirmed that chlordiazepoxide diminished the well-established incidence of arrhythmias (A-V blocks and nodal escapes) in five nervous pointer dogs. It is known that this drug normalizes behavior and aids in the bar-pressing performance of nervous dogs. Nervous dogs tend to have low heart rates (HRs) while normals have higher HRs. Chlordiazepoxide increased HRs in our five nervous dogs, and we postulated that HR increase would be less or none in normals. This was confirmed in a later study of five normals. A further study of eight normal dogs and eight nervous dogs essentially reproduced these findings, suggesting the possibility that the slow heart rates and the behavioral abnormality have a common basis, expected to be some CNS biochemical lesion.     

Sex characteristics,task clarity,and authority

This study was conducted to investigate the effect of sexual stereotyping on the exercise of authority. The hypotheses were that the sexual composition of the group affects the authority behavior of group leaders when the task has low clarity but that sex characteristics have no effect on authority behavior when the task has high clarity. These predictions were expected to hold both in situations where there is a direct association between sex and the task ability and in situations where no such connection is established. As predicted, no significant difference was found in the number of high control acts made by male and female leaders in the high task clarity conditions, even when sex was directly related to the task ability. Also as hypothesized, sex effects did operate strongly in the low task clarity conditions. Male leaders made significantly more high control acts than female leaders, even in conditions where no prior relation was established between sex and the task ability. Thus, these results indicate that the effect of sex characteristics on the exercise of authority is enhanced in low task clarity situations and is neutralized in high task clarity situations.A preliminary version of this paaper was presented at the West Coast Conference for Small Group Research, San Francisco, California, April 24, 1974. We would like to acknowledge the comments made by Anne McMahon and Mary Walshok and the research assistance provided by Sue Aldrich, Patti Baird, Jim Hart, Debbie Jones, Glenn Kassel, Jane Morrison, Karen Scheblein, and Kay Smith.     

Correlations of normality and nervousness with cardiovascular functions in pointer dogs

Methylphenidate, 0.5 mg/kg, injected intravenously, was used in 10 normal (A line) and 10 genetically nervous (E line) dogs in a blind-design experiment to aid in prediction, from cardiovascular recordings alone, of behavioral normalityversus nervousness. The prediction was 75 per cent correct, based on heart rate (HR), form of the electrocardiogram (EKG), pattern of sinus arrhythmia, and pattern of HR response to methylphenidate. Nervous dogs were found to have slower baseline HR’s, delayed return of HR to baseline after methylphenidate, greater occurrence of baseline EKG abnormalities and much greater frequency of these after methylphenidate. Degree of nervousness was found to correlate rather highly (1)negatively with baseline HR level, (2)negatively with speed of BP response, and (3)positively with frequency of some of the EKG manifestations. These data, indicative of a relative inertness of physiological functions of nervous pointer dogs compared with normal pointers, are consistent with the behavioral and some of the biochemical findings previously reported.     

Deficits in prospective memory following damage to the medial subdivision of the mediodorsal thalamic nucleus

Identifying the neurocognitive mechanisms that lead individuals remembering to execute an intention at the right moment (prospective memory, PM) and how such mechanisms are influenced by the features of that intention is a fundamental theoretical challenge. In particular, the functional contribution of subcortical regions to PM is still unknown. This study was aimed at investigating the role of the medial subdivision of the mediodorsal thalamic nucleus (mMDT) in PM, with particular focus on the processes that are mediated by the projections from/to this structure. We analysed the performance of a patient (OG) with a right-sided lesion involving the mMDT in a series of PM tasks that varied for focality (i.e., overlapping of processes for the PM and ongoing tasks) and emotional valence of the stimuli, comparing the patient's performance with that of a control group. We found that the mMDT damage led to deficits in PM that were modulated by focality and emotional valence. OG indeed showed: a greater cost in the ongoing performance when a non-focal PM task was added; a slowing down in retrieving the intentions, in particular when these were associated with focal PM cues; an abnormal performance in the task with positive PM cues. Our findings provide evidence of a contribution of mMDT to PM and suggest a modulation of prefrontal-dependent strategic monitoring and a possible interaction with the limbic structures in the integration of emotion and PM processes. They also give support to the still controversial idea that connections with the perirhinal cortex mediate familiarity-based recognition.