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In this review we present some current applications of electrogastrography, relationships between the electrogastrogram (EGG) and electrical and contractile activity of the stomach, EGG recording technique, and the current status of electrogastrography. The authors conclude the following: (I) The 3 cpm frequency of the EGG reflects the frequency of pacesetter potentials occurring at the serosal and mucosal surfaces of the stomach. (2) An increase in the contractile activity of the corpus-antrum is associated with an increase in the amplitude of the 3 cpm EGG signal. (3) Tachygastria (5-9 cpm waves) recorded with the EGG reflects identical frequencies recorded with mucosal electrodes from the gastric antrum. (4) Low frequency components (approximately 1 cpm) appear In the EGG signal but their physiological significance is unknown at this time. [ABSTRACT FROM AUTHOR]

The results of three experiments are reported in which simulated race situations, i.e., GET SET--5 sec--GO, were used to examine the anticipatory HR response and RT. The first study involved sprinting up a flight of stairs and the second and third a bicycle sprint. The typical pattern of phasic HR found was acceleration until I sec prior to GO and then deceleration. Tonic HR appeared to be a function of the degree of anticipated physical effort. Muscle potential, recorded in the first experiment, appeared to be related to HR. No systematic relationship was found between HR and RT. [ABSTRACT FROM AUTHOR]

Three experiments were conducted to study the behavioral and physiological effects of false heart rate feedback. These experiments were based on a paradigm advanced by Valins (1966) who stressed that the mere belief that one's heart beat is changing, regardless of actual physiological changes, is sufficient to affect behavior. The three experiments involved (1) a replication of Valins' original study with a closer examination of actual physiological responses, (2) examination of the role which subject attention plays, and (3) a substitution of unpleasant stimuli for the pictures of nude females used in the earlier studies. It was concluded that what Valins ascribed to merely the belief that physiological actions were occurring may have, in fact, been due to actual physiological changes precipitated by a general attention factor. [ABSTRACT FROM AUTHOR]

Compares subjective and physiological adaptation, as measured by magnitude of galvanic skin response (GSR), to electric shock and auditory noise. GSR adaptation shown by noise subjects with an increase in subjective intensity reports; Importance of anticipation in terms of level of arousal at the onset of the session.

The effects of four types of deep breaths on the latency, the magnitude and the duration of finger volume pulse, heart rate and galvanic skin responses were studied in a quasi-learning situation. The respiratory stimuli were normal inspirations, three times deeper than normal, six times deeper and fast, and six times deeper and slow. Twenty Ss took each type of deep breath in random order six times in response to specific lights. Graphs and statistical tests are presented summarizing the above relationships and two unexpected findings are discussed. [ABSTRACT FROM AUTHOR]

Ability to control GSRs through the use of ideational stimulation was studied in 26 professional actors. During one 10-mm period, "Respond," Ss had to make as many GSRs as possible; during the other period, "Rest," Ss were instructed to inhibit their GSRs. All Ss received continuous visual feedback of their responses during both periods. No relationship was found between ability to control GSRs and emotional expression as measured by the ratings of directors. However, as predicted, method actors performed at a significantly higher level than non-method actors. An additional finding was that those actors who normally experience sweating as their primary response to stress performed at a higher level than non-sweaters. [ABSTRACT FROM AUTHOR]

The purpose of this study is to compare the effects of response-contingent and random aversive auditory stimulation on gastrointestinal motility. Ss were presented with four consecutive 10-min treatment periods in the following order: response-contingent (R-C), random, R-C, random. During R-C, S could avoid the 5-sec 90 db tone, which was programmed to come on every 30 sec, by pressing a key once during the 5 sec preceding the tone. During the random period, S had no control over the presentation of the tone. The results indicated that during R-C, amplitude of gastrointestinal motility was significantly greater and latency briefer than under random conditions. These results are accounted for in terms of the dual role of the tone in the R-C condition, i.e. it is aversive and it signifies to S that his time estimation was incorrect. [ABSTRACT FROM AUTHOR]

Evidence is provided showing that there is very little change in pulse volume in the ear lobe as a function of the usual types of psychological stimuli. On the one hand, this makes ear lobe plethysmography an excellent source of a signal to trigger a cardiotachometer for investigators interested in pulse rate who do not want to, or cannot, use EKG recording. On the other hand, this makes the ear lobe an inappropriate place from which to record vasomotor reactivity. [ABSTRACT FROM AUTHOR]

The conventional placement of electrodes for recording forehead, or "frontalis" EMG attenuates forehead potentials by placing one electrode over each frontalis muscle. The placement also precludes exploration of differences in the activity of the two muscles, and is influenced by potentials arising in nearby muscles. An alternative unilateral bipolar lead placement is suggested and demonstrated. [ABSTRACT FROM AUTHOR]