bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Production of Specific Decreases in Interbeat Interval and the Molor Skills Analogy
Authors: Johnston Derek W. , Lethem Jane 
Published: February 2007

ABSTRACTJohnston (1977) has argued that studies ofthe self‐control of heart rate have not provided clear support for thetheor that biofeedback aided leaming is analogous to a motor skill. This could be because the tasks studied are not modelled closely enough on the skills analogized and because feedback might aid control rather than leaming. These possibilities were examined in a series of five studies on decreasing interbeat interval (i.e. increasing heart rate) by a specific amount. It was shown in two studies that analogue feedback was superior to binary. The effect of frequency of feedback was weaker but frequent feedback was better than infrequent in two out of three studies. Feedback plus verbal instructions was better than verbal instructions alone and performance deteriorated when feedback was withdrawn. The results support the view that heart rate control does resemble a motor skill when the task set the subject has close similarity to a conventional skilled task and that, under these circumstances, feedback primarily aids performance and not leaming.
The Topography of Event‐Related Slow Potentials During Reflex Movement (Ankle Jerk) Conditioning
Authors: Ragazzoni A. , Bruneau N. , Martineau J. , Roux S. , Lelord G. 
Published: February 2007

ABSTRACTThe morphology and scalp distribution of slow negative potentials elicited in type I conditioning, requiring no instruction, were studied. The paradigm involved the presentation of a conditioned stimulus (S1), followed 1500 msec later by an unconditioned stimulus (H), the electrical stimulation of the popliteal nerve evoking an ankle jerk (Hoffmann reflex).Our topographical data showed that two components develop in the interstimulus interval S1‐H: a large fronto‐central early component followed by a late centro‐parietal negative component which precedes the H‐reflex movement. This negative shift terminates abruptly in a positivity post‐H‐reflex.These anticipatory components show similarities, particularly at the parietal site, to slow waves elicited in a CNV paradigm involving the presentation of an indicative stimulus (S1) followed by an imperative stimulus (S2) requiring an operant motor response.These results are discussed in terms of conditioning, arousal, and early preparatory and time estimation processes.
Effects of Control Over Aversive Stimulation and Type A Behavior on Cardiovascular and Plasma Catecholamine Responses
Authors: Contrada Richard J. , Glass David C. , Krakoff Lawrence R. , Krantz David S. , Kehoe Kathleen , Isecke William , Collins Carla , Elting Ellen 
Published: February 2007

ABSTRACTCardiovascular, plasma catecholamine, and behavioral effects of control over aversive events were studied in 87 Type A and B male adults. Subjects performed a choice reaction time (RT) task during which they received loud noise bursts and/or electric shocks on designated trials. About half of the cases were told they could avoid noise and shock by attaining a predetermined criterion of RT speed (Contingency). The remaining half were instructed that noxious stimulation would be delivered randomly, irrespective of their performance (No Contingency). Half of the cases in each treatment were exposed to high frequency of aversive stimulation (High FAS), whereas the remaining half received low frequency of such stimulation (Low FAS). Within Contingency, High and Low FAS were designed to signify failure and success, respectively. Aversive stimulation in No Contingency was gratuitous and, therefore, did not convey information about performance. Relative to No Contingency, the Contingency treatment induced greater increases in RT speed, systolic and diastolic blood pressure, and plasma epinephrine. Differential FAS did not potentiate these differences. It also was found that the Type A subjects had higher systolic blood pressure and heart rate responses than Type B's. The prediction that Contingency (particularly with High FAS) would elicit greater physiologic and behavioral hyperresponsiveness in A's than B's received some support in the data for RT speed and plasma NE. Findings were discussed in terms of sympathetic activation of hemodynamic changes under conditions of active coping. Consideration was given to the role of the sympathetic nervous system and Type A behavior in cardiovascular disease.
Experimenter Expectancy Effects in Frontal EMG Conditioning
Authors: Segreto‐Bures Joyce , Kotses Harry 
Published: February 2007

ABSTRACTNonspecific factors such as placebo or expectancy effects may materially influence therapeutic outcome in EMG relaxation training. Yet, controlling for the expectations of experimenters has received little attention even though Rosenthal's Experimenter Expectancy Effect is well‐documented. This study examined the effects of experimenter expectancy on frontal EMG conditioning. During training, experimenters were given either no expectancy or led to believe that EMG conditioning would he either difficult (low expectancy) or easy (high expectancy) to achieve. Then, the three groups of experimenters collected data from subjects undergoing 20 min of either contingent or noncontingent reinforcement for frontal EMG decreases. Postexperimental credibility checks indicated that experimenters were unaware they were being studied but could identify their expectancy condition when informed of the three conditions. Differential EMG behavior was observed between groups conditioned by experimenters with no expectancies, with contingent subjects achieving significantly lower EMG levels than noncontingent subjects. Differences were not exhibited, however, between contingent and noncontingent subjects trained by experimenters with either low or high expectancies. These findings suggest that experimenters with prior expectations may covertly communicate to subjects response sets that interfere with acquisition of differential EMG behavior.
Effect of Varying the Time of Sleep on Sleep, Vigilance, and Self‐Rated Activation
Authors: Cairns J. , Knowles J. B. , MacLean A. W. 
Published: February 2007

ABSTRACTThe effect of varying the time of sleep (2100‐0500, 2400‐0800, and 0300‐1100 hrs) on the sleep, vigilance, and self‐rated activation of 9 normal subjects was assessed. REM% increased, and Stage 2% decreased, with progressively later bedtimes. An hour by hour analysis showed, however, that the increase in REM sleep was confined to the second 3 hrs of sleep. Vigilance and self‐rated activation, assessed 30 min after waking, at midday and in the early evening, did not differ between conditions but varied reliably with time of day. It is concluded that shifts away from the conventional 2400‐0800 sleep period do not impair performance. Rather, the changes in sleep (between conditions) and performance (within conditions) are, in the main, consistent with the known circadian rhythms of REM sleep propensity and performance efficiency.
Hemispheric Specificity: A Physiological Concomitant of Hypnotizability
Authors: Macleod‐Morgan Crisetta , Lack Leon 
Published: February 2007

ABSTRACTMacLeod‐Morgan (1979) found a significant relationship between hypnotizability and EEG hemispheric specificity. Hemispheric specificity is defined as the extent to which the alpha ratio between hemispheres changes during lateralized task performance. The present study was designed to replicate and extend this finding. EEG was recorded bilaterally from 44 subjects during performance of two right‐ and two left‐hemisphere discontinuous tasks from MacLeod‐Morgan (1979), and four new comparable continuous tasks. As predicted, significant differences were found in hemispheric specificity between low and high hypnotizables especially during the continuous tasks.
Psychopathy and Physiological Activity During Anticipation of an Aversive Stimulus in a Distraction Paradigm
Authors: Hare Robert D. 
Published: February 2007

ABSTRACTTwo investigators independently rated 51 white, male prison inmates on a 7‐point psychopathy scale (interrater reliability = .89). The combined ratings were used to divide the inmates into low (1), medium (M). and high (H) psychopathy groups of 17 subjects each. Following a sample trial, each inmate was given two trials in which he could choose how to spend his time during a 5–6 min wait for an aversive stimulus (120dB tone). Three choices were available: 1) continuous white noise, 2) a recording of a nightclub comedian, or 3) a continuous tone that changed in frequency 10 sec before delivery of the aversive stimulus. The aversive stimulus could be avoided on one trial but not on I he other (the order was counterbalanced). When the aversive stimulus was unavoidable (Trial UA), 46 (90.2%) of the inmates spent all or most of their time listening to the comedian, i.e., they adopted a “nonvigilant” strategy, while 38 (74.5%) adopted this strategy when the aversive stimulus was avoidable (Trial A). There were no group differences in the type of strategy used on either trial, or in the physiological responses given by the nonvigilant subjects on Trial UA. Group H tended to give smaller electrodermal responses and a larger increase in HR in anticipation of the sample tone than did Group L, a pattern that is consistent with previous research using classical conditioning or “count down” procedures. On Trial A the nonvigilant subjects in Group H showed a significantly smaller increase in nonspecific skin conductance activity than did Group L. It is suggested that making use of distraction when an aversive stimulus is avoidable results in less conflict and heightened emotional arousal in psychopaths than in other inmates. Some speculations on how psychopaths cope with threat are offered.
P3 and Stimulus Incentive Value
Authors: Begleiter H. , Porjesz B. , Chou C.L. , Aunon J.I. 
Published: February 2007

ABSTRACTEvent‐related potentials were recorded to two equiprobable, task‐relevant visual stimuli (0.00 and 1.00) under three different conditions. In the baseline condition subjects attended to both stimuli and pressed the appropriate button to each stimulus. In the Accuracy/Incentive condition subjects earned one dollar each time the 1.00 stimulus was presented by accurately pressing the appropriate button after each stimulus. Incorrect presses to either stimulus resulted in the loss of a dollar. In the Speed‐Accuracy/Incentive run, subjects could only earn one dollar to the 1.00 stimulus if they accurately pressed the correct button within 350 msec. Reaction times greater than 350 msec to either stimulus resulted in the loss of a dollar. The results indicate that the amplitude of the P3 component is significantly different to equiprobable task‐relevant stimuli with differential incentive values. P3 may reflect the subjective motivational properties of stimuli.
Brain Potentials Related to Stages of Sentence Verification
Authors: Fischler Ira , Bloom Paul A. , Childers Donald G. , Roucos Salim E. , Perry Nathan W. 
Published: February 2007

ABSTRACTSubjects were shown the terms of simple sentences in sequence (e.g., “A sparrow / is not / a vehicle”) and manually indicated whether the sentence was true or false. When the sentence form was affirmative (i.e., “X is a Y”), false sentences produced scalp potentials that were significantly more negative than those for true sentences, in the region of about 250 to 450 msec following presentation of the sentence object. In contrast, when the sentence form was negative (i.e., “X is not a Y”), it was the true statements that were associated with the ERP negativity. Since both the false‐affirmative and the true‐negative sentences consist of “mismatched” subject and object terms (e.g., sparrow / vehicle), it was concluded that the negativity in the potentials reflected a semantic mismatch between terms at a preliminary stage of sentence comprehension, rather than the falseness of the sentence taken as a whole. Similarities between the present effects of semantic mismatches and the N400 associated with incongruous sentences (Kutas & Hillyard, 1980) are discussed. The pattern of response latencies and of ERPs taken together supported a model of sentence comprehension in which negatives are dealt with only after the proposition to be negated is understood.
A Device for Ambulatory Skin Conductance Monitoring
Authors: Simpson Alan , Turpin Graham 
Published: February 2007

ABSTRACTThe design of instrumentation for the ambulatory measurement of skin conductance (SC) is discussed. Two problems which are frequently encountered concern size constraints and the provision of a sufficient dynamic range. A circuit description which overcomes these problems is given along with details of its construction. This device utilises an AC‐coupled amplifier stage for Skin Conductance Responses (SCRs) and a DC‐coupled amplifier stage for Skin Conductance Level (SCL). Its use in conjunction with a portable instrumentation cassette recorder is described.
Psychophysiological Activity and the Buildup and Release of Proactive Inhibition in Short‐Term Memory
Authors: Wilson Keith G. 
Published: February 2007

ABSTRACTOne interpretation of the buildup and release of proactive inhibition (PI) in short‐term memory is that the repetition of similar items leads to a decrement in attention which is reinstated via the orienting response (OR) when the novel shift items are presented. In a test of this hypothesis, 72 subjects performed the PI task while skin conductance and heart rate were recorded. Half the subjects received a change in semantic category on a test trial, while the other half did not. In addition, subjects differed with respect to whether the test trial also included a single presentation of a tone to which they had previously habituated, a novel tone not previously encountered, or no tone. In general, the results provided no support for the OR interpretation of PI. While the semantic change led to improved recall, it was not associated with a differential pattern of physiological responding. Furthermore, the interpolated tones resulted in dishabituation of the SCRs for the following memory items, but had no effect on memory performance.
On the Dependence of P300 Latency on Stimulus Evaluation Processes
Authors: Magliero Anthony , Bashore Theodore R. , Coles Michael G.H. , Donchin Emanuel 
Published: February 2007

ABSTRACTMcCarthy and Donchin (1981) found that the latency of a late positive component of the event‐related potential (ERP) was influenced by the presence of noise in a stimulus matrix but not by the compatibility between the stimulus presented and the response required. They concluded that this component is a P300 and that its latency was influenced by stimulus evaluation but not by response selection processes. The present experiments were designed to confirm that the component identified by McCarthy and Donchin was indeed a P300 and to determine if its latency varies systematically with increases in stimulus evaluation time produced by graded changes in noise level.In Experiment 1, subjects performed a standard oddball task in which they were required to count the rarer of two stimuli (the words RIGHT or LEFT) which were, or were not, embedded in a noise matrix (characters from the alphabet). The positive component of the ERP, whose amplitude was larger for rare target stimuli, was labeled a P300, and the latency of this component was longer when the stimuli were embedded in noise. In Experiment 2, subjects performed a choice reaction time task. Following the procedures used by McCarthy and Donchin, stimulus words RIGHT and LEFT required right or left hand responses depending on the presence of a cue word SAME or OPPOSITE which preceded the stimulus. Stimulus words were presented in four different degrees of noise, the levels of which were manipulated by varying the set size of the alphabetic characters which could surround the stimulus words. Reaction time increased both with noise (by 325 ms) and as a function of stimulus‐response incompatibility (by 127 ms). In contrast, P300 latency increased substantially with noise (by 200 ms) but, to a much lesser extent (by 14 ms), with response incompatibility. These results indicate that the P300 is sensitive to the ease with which a target stimulus can be discriminated from noise. They confirm that P300 latency can be used as a measure of the timing of stimulus evaluation processes that is relatively independent of response selection and execution.
Temporal Arrangement of Signals in Heartbeat Discrimination Procedures
Authors: Clemens William J. 
Published: February 2007

ABSTRACTThree experiments are reported which were designed to define optimal placements of S+ signals in Whitehead‐type discrimination procedures by asking when in the cardiac cycle signals are perceived as most coincident with heartbeats. In Experiment I subjects discriminated signals delayed either 0 or 100 ms from the R‐wave from signals delayed 400 ms. In Experiment II subjects chose signals delayed 0, 100, or 200 ms as more synchronous with heartbeats than signals delayed 300 or 400 ms. In Experiment III no central tendency emerged when subjects adjusted a signal through delays of 0, 60, 120, 180, and 240 ms seeking the value most synchronous with heartbeats. It is concluded that subjects can reliably discriminate events in the first quarter second of the cardiac cycle from events occurring later (although the functional significance of this ability remains obscure) and that S+ signals in such procedures should be placed within that time period.
Spontaneous Vigilance Fluctuations in the Daytime
Authors: Okawa Masako , Matousek Milos , Petersén Ingemar 
Published: February 2007

ABSTRACTSpontaneous fluctuations of vigilance during the daytime were studied in 412 electroencephalographic (EEG) records from 9 subjects. The EEGs were recorded repeatedly 19–25 times between 0800 and 1900 in each subject. Except during the 5‐min recording periods when seated subjects were examined with their eyes closed, the subjects were encouraged to engage in their normal daytime activities, such as reading and knitting. The changes in vigilance level were indicated by EEG measures based on automatic analysis. Statistical analyses of the data showed that vigilance fluctuations occurred rhythmically with a period between 60 and 110 min. The ultradian vigilance rhythms were detectable even though the subjects were engaged in normal daytime activity. Individual patterns of ultradian rhythms were, however, observed to be relatively unstable when within‐subjects comparisons were made between experiments conducted one to six weeks apart.
Hemispheric Asymmetry and Bilateral Electrodermal Recordings: A Review of the Evidence
Authors: Hugdahl Kenneth 
Published: February 2007

ABSTRACTBilateral electrodermal recordings are often used in psychophysiological research as a measure of functional hemispheric asymmetry. Although significant differences between left and right hand recordings are reported in the literature, the obtained differences are often in different directions. The purpose of the present paper was to review empirical evidence related to the issue of bilateral electrodermal recordings in research on hemispheric asymmetry. Special reference is made to the current controversy concerning contralateral inhibition vs. excitation or facilitation as the underlying mechanism for reported differences in performance of typical hemisphere‐specific tasks. After reviewing the evidence, which is contradictory concerning several of the more critical parameters, the conclusion is that bilateral electrodermal recordings have not been unambiguously related to hemispheric asymmetry. However, when asymmetry between the hands is clearly demonstrated, this reflects an asymmetry in the functioning of the cerebral hemispheres.
Heart Rate Change in Type A and Type B Males as a Function of Response Cost and Task Difficulty
Authors: Perkins Kenneth A. 
Published: February 2007

ABSTRACTTonic changes in heart rate (HR) and somatic motor activity were monitored in 70 Type A and 70 Type B males to determine if these groups differ in psychologically‐mediated HR reactivity to a specific appetitive situation. A and B types were defined by extreme scores on the Jenkins Activity Survey. Subjects performed a continuous button‐pushing task during a practice trial and 4 trials involving high (loss of money), low (loss of points), or no response cost (RC) for performance failure, and high, moderate, low, or no levels of failure feedback on performance. Greater HR increases from practice were predicted for high RC vs. low RC, and for Type As vs. Type Bs. Additionally, in the high RC condition, HR was expected to diminish across trials more in those receiving high and low failure feedback compared with those receiving moderate failure feedback. Results confirmed the first two expectations. Furthermore, the HR difference between Type As and Type Bs was magnified under high RC conditions. The last expectation was not confirmed, but further analyses suggested that failure feedback influenced Type Bs but not Type As. Greater intrinsic appetitive motivation of Type As may account for their greater HR increase in response to opportunities for active avoidance, as well as for reward.
Duration and Placement of Sleep in a “Disentrained” Environment
Authors: Campbell Scott S. 
Published: February 2007

ABSTRACTSleep/wake cycles of 9 young adults were electrographically recorded during 60 hrs of enforced bedrest. During this period subjects were required to lie quietly, with no time cues and minimal exogenous stimulation. Sleep and wakefulness patterns were clearly modified under these conditions. There was an alternation of waking periods with an average length of 2.7 hrs and sleep episodes with a mean duration of 2.99 hrs. Eighty percent of both sleep and waking periods were less than 4 hrs duration. The circadian pattern of sleep period duration persisted in disentrainment, but temporal organization of sleep episodes was substantially disrupted; sleep episodes occurred throughout the 24‐hr day. The results suggest the presence of two distinct components of the human sleep system–one, sleep duration, is controlled by an endogenous circadian oscillatory system; another, sleep placement, is controlled primarily by behavioral controls, in the form of social and occupational pressures, and self‐imposed behavioral alternatives to sleep.
Cerebral Lateralization and Heartbeat Discrimination
Authors: Hantas Michael N. , Katkin Edward S. , Reed Sheila D. 
Published: February 2007

ABSTRACTThis study examined individual differences in visceral perception as a function of cerebral lateral preference as assessed by conjugate lateral eye movements. Subjects were classified as “left movers” (i.e., right hemisphere preferent) or “right movers” (i.e., left hemisphere preferent). “Right movers” performed at chance level on a heartbeat detection task, whereas “left movers” performed significantly above chance. With knowledge‐of‐results (KOR) training all subjects showed a significant increment in performance, but the left movers maintained their superiority. These results support the hypothesis that performance on a visceral perception task may be subserved by relative activation of the right hemisphere.