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Objective To identify the possible contribution of electromyogram (EMG) to scalp electroencephalogram (EEG) rhythms at rest and induced or evoked by cognitive tasks. Methods Scalp EEG recordings were made on two subjects in presence and absence of complete neuromuscular blockade, sparing the dominant arm. The subjects undertook cognitive tasks in both states to allow direct comparison of electrical recordings. Results EEG rhythms in the paralysed state differed significantly compared with the unparalysed state, with 10- to 200-fold differences in the power of frequencies above 20 Hz during paralysis. Conclusions Most of the scalp EEG recording above 20 Hz is of EMG origin. Previous studies measuring gamma EEG need to be re-evaluated. Significance This has a significant impact on measurements of gamma rhythms from the scalp EEG in unparalysed humans. It is to be hoped that signal separation methods will be able to rectify this situation.

This experiment investigates the relationship between results produced by an expert system (ES), its physical structure and features, and the user's commitment and confidence in its solutions. One hundred one subjects among four MPA programs were asked to evaluate ten applicants for a government budget officer position. Among the findings: decision makers who utilized the ES made higher quality decisions but exhibited less confidence and commitment than did those who worked without an ES; decisionmaker involvement in the decision process corrected for this disparity. We discuss the implications for ES design and future research.

Objective Fast electrical rhythms in the gamma range (30–100 Hz) in scalp (but not intracranial) recordings are predominantly due to electromyographic (EMG) activity. We hypothesized that increased EMG activity would be augmented by mental tasks in proportion to task difficulty and the requirement of these tasks for motor or visuo-motor output. Methods EEG was recorded in 98 subjects whilst performing cognitive tasks and analysed to generate power spectra. In four other subjects, neuromuscular blockade was achieved pharmacologically providing EMG-free spectra of EEG at rest and during mental tasks. Results In comparison to the paralysed condition, power of scalp electrical recordings in the gamma range varied in distribution, being maximal adjacent to cranial or cervical musculature. There were non-significant changes in mean gamma range activity due to mental tasks in paralysed subjects. In normal subjects, increases in scalp electrical activity were observed during tasks, without relationship to task difficulty, but with tasks involving limb- or eye-movement having higher power. Conclusions Electrical rhythms in the gamma frequency range recorded from the scalp are inducible by mental activity and are largely due to EMG un-related to cognitive effort. EMG varies with requirements for somatic or ocular movement more than task difficulty. Significance Severe restrictions exist on utilizing scalp recordings for high frequency EEG.

Much has been written about social support, but little is known about the processes that promote continuity or discontinuity in supportive relationships. A proposed model of relationship processes (Levitt, 1991) specifies that changes in the quality of close relationships are likely to occur when expectations for social support are tested and disconfirmed. Relationships are particularly vulnerable to change after major life events, such as childbirth, when increased support needs precipitate the testing of expectations. In a preliminary assessment of this model, 43 mothers were interviewed at 1 month and 13 months after birth. Changes in relationship satisfaction were related strongly to the extent to which mothers perceived that their expectations for support had been disconfirmed. The results are consistent with the proposed model and suggest the value of considering the effects of social support in light of the individual's expectancies.

Pupillary dilation of five groups of 10 subjects each was conditioned by pairing an auditory CS and an electric UCS for nine trials. Two additional groups of 10 subjects each served as controls for pseudoconditioning and adaptation during conditioning. At the onset of the six extinction trials, four of the five conditioned groups were given different conditions designed to induce awareness of the termination of the UCS if cognition governed extinction. The fifth conditioned group was given conventional extinction trials as a control. The four cognition-inducing conditions resulted in complete one-trial extinction supporting a one-rather than a two-factor explanation of this phenomenon. The five conditioned groups demonstrated complete one-trial acquisition as did also one of the two control groups given false expectation of a CS-UCS. This suggests that acquisition was also completely controlled by cognition.

12. Roosevelt, Theodore, The New Nationalism, New York: Outlook Publishers, 1910. 13. Hamilton, Edward, "Non-Constitutional Management of a Constitutional Problem," Daedalus, Winter 1978. 14. The most important proposals before Congress are fiscal note bills S.43 (Sasser, D. Tenn.) and HR. 1465 (Zeferetti, D. N.Y.) which call for the Congressional Budget Office to conduct cost estimates of major regulation legislation having an expected economic impact of $200 million or more, or a substantial impact on any level of government or geographic region. Although the bills, with amendments, are expected to pass, CBO has raised objections citing the difficulties and expense of accurate cost estimating. A Paperwork Reduction Act was passsed in late 1980. A mandate cost reimbursement proposal by John Burton of California is not expected to move. The GAO is preparing an extensive report on mandating by the federal government on the states for the use of Congress.