摘要:

ABSTRACTSleepers were studied in their homes to obtain measures of relationships between (a) discrepancies between reported and recorded sleep, (b) degree of sleep difficulty, and (e) reported cognitive activity. Twelve good sleepers and 12 insomniacs were questioned immediately after lights out, at the occurrence of the first sleep spindle or K‐complex, 10 min after the second sleep onset, 5 min after the onset of the first REM period, 10 min after the onset of the first stage 2, during subsequent periods of REM and stage 2 sleep, and at spontaneous arousals. Subjects responded to questions regarding mental content (thought vs picture, awake vs asleep, audience vs actor), estimated total time, and estimated total sleep time since the previous arousal. Insomniacs overestimated sleep difficulty only at 10 min after the second spindle and at spontaneous arousals. Reports of “picture” and “actor” were associated with sleeping difficulty. Persons who reported being “awake,”“actor,” and “picture” showed significantly greater discrepancies between reported and recorded sleep than persons who reported “sleep,”“audience,” or “thought”. The results are discussed in terms of implications for increased understand

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02151.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTSystolic time interval methodology was used to explore the relative contributions of intracardiac and vascular delays to modifications in pulse transmission time elicited by a series of behavioural and physical challenges. The following variables were recorded on every cardiac cycle: interbeat interval (IBI), the interval between Q and R wave of the EKG, Q wave to pulse arrival (QPT) at the ear and wrist, left ventricular ejection time, and cardiac pre‐ejection period (PEP). The true arterial pulse transit time (PTT), inversely related to pulse wave velocity, was calculated by subtracting PEP from QPT.Modifications of QPT were generally associated with PEP rather than PTT responses. But QPT to the ear and wrist were not equivalent; PEP showed closer correlations with QPT to the ear, while PTT was correlated more consistently with QPT to the wrist. Similar patterns were observed with monitoring from the Q and R waves of the EKG. Important differences also emerged between individuals in the degree to which QPT reactions were correlated with the cardiac or vascular components.A supplementary analysis of correlations between blood pressure and the components of QPT was carried out through hand‐scoring of systolic time intervals. Both PEP and PTT contributed to the correlations of systolic pressure with QPT. The uses of pulse transmission times as indices of pulse wave velocity, or alternatively of PEP and ventricular contractility, are conside

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02152.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTIn some situations subjects' predictions of future events do not accurately reflect the subjective probability associated with these events. We set up such a situation by manipulating the payoff structure in a prediction paradigm, and found that P300 provides an index of the processes responsible for subjective probability, or expectancy, not obtainable from overt predictions. Sixteen subjects were required to predict, on each trial, whether a 1, 2, or 3 would appear on a display. The numbers appeared randomly with probabilities .45, .10, and .45, respectively. In one condition subjects were given bonuses according to an all‐or‐none payoff function in which they received one cent if they predicted correctly, and nothing if they were incorrect. In a second condition bonuses were determined by a linear payoff function in which subjects were paid one cent if they predicted correctly, and one‐half cent if they were off by one (e.g., predict 1 and 2 appears). After each condition subjects estimated the actual number of stimuli presented. These estimates were the same for both conditions, although predictions differed radically, with 2 predicted much more frequently in the linear condition. P300 area was largest for the rare event (2), and the relationship between P300 and probability was unaffected by payoffs. Our design did introduce differences between conditions in the overall “riskiness’ of predictions, and the strategies adopted by most subjects also resulted in differences in the salience, or task relevance, of the feedback stimuli. These differences resulted in an overall increase in P300 in the all‐or‐none condition. A relationship also emerged between the subjects' strategies and their ERPs. Subjects who adopted more effective strategies responded differentially to feedback from high and low risk predictions, whereas the o

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02153.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe extraction of mean amplitude from integrated electromyographic (IEMG) responses provides a valid but limited measure of muscle action potentials (MAPs). More comprehensive topographical analyses of IEMG responses based on frequency analyses are unsatisfactory since IEMG responses are aperiodic, and autoregressive procedures may be unsatisfactory since autocorrelations constitute an irreversible transformation of the original waveform, represent a substantial loss of information in contrast to the original waveform, and harbor little apparent relationship to MAPs. In a Theoretical Investigation, a mathematical procedure is developed to quantify topographical features of both the amplitude and temporal dimensions of the IEMG response. Procedures for extracting these parameters and the relationship between each and the recruitment of MAPs are illustrated. In a Validation Study, surface electromyograms are recorded from the preferred forearm under various conditions of mild isometric forearm contraction. Results support the viability, reproducibility, and validity of the topographical analysis.

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02154.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02155.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTThe significance of respiratory influences upon cardiovascular functioning has been much neglected in the psychophysiological literature. Various phasic and nonphasic respiratory parameters manifest marked and specific effects upon numerous cardiac and circulatory events. Ventilatory patterns associated with stress responses, furthermore, bring about cardiovascular alterations indicative of dysfunction and risk, even when these ventilatory patterns are voluntarily enacted by normal individuals under nonstressful circumstances. Evidence is presented which suggests that respiratory processes may contribute significantly to cardiovascular competence and dysfunction. The implications of this theoretical approach for psychophysiological research are also discussed.

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02156.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02157.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTCardiovascular responses of 72 young men were assessed during an appetitive reaction time task where winning money incentives was either easy, difficult, or impossible. The impossible condition led to reduced responses (e.g., longer pre‐ejection period (PEP) and pulse transit time (PTT) and greater falls in systolic and diastolic pressures) as well as reports of trying less hard than the easy or the difficult condition. Regardless of task difficulty, subjects showing greater heart rate (HR) increases at task onset maintained higher HR levels than low HR reactors throughout the task. Overall, these high HR reactors also showed higher SBP and shorter PEP, PTT and left ventricular ejection time than low HR reactors, although these differences were less pronounced by the end of the task. Based on their responses to various standardized inventories, high and low HR reactors did not differ in behavioral traits such as Type A, suppressed hostility, or active coping as the preferred coping style. However, a subsample of subjects with extreme scores indicating suppressed hostility (N = 12) did show elevated HR and systolic pressure during both relaxation and the appetitive tas

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02158.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02159.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACTEEG activity within the 40 Hz band was monitored during several tasks and during a non‐task condition. Twelve right‐handed subjects diagnosed as having Alzheimer's type dementia were studied. Results from this group were compared to a group of neurologically normal subjects of comparable age and IQ. Results show that while the normal group exhibited appropriate increases in 40 Hz activity during problem solving, the Alzheimer's type dementia group did not. In addition, the task appropriate lateralization of 40 Hz activity seen in the normal group was absent in the Alzheimer's type dementia gr

ISSN:0048-5772    

DOI:10.1111/j.1469-8986.1983.tb02160.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY