bluuebunny/crossref_metadata_2025 huggingface dataset:
Physical Fitness, Exercise, and REM Sleep Cycle Length
Authors: Trinder John , Stevenson Janne , Paxton Susan J. , Montgomery Iain
Published: February 2007

It has been suggested, on the basis of phylogenetic and ontogenetic data, that the length of the REM sleep cycle is negatively related to metabolic rate. However, experimental studies have not consistently found this relationship. We report the effects of two variables, the level of physical fitness and the amount of daytime exercise, on sleep cycle length. Since both physical fitness and exercise involve increased levels of energy expenditure, and thus increased metabolic rate, it was predicted that they would he negatively related to cycle length. The sleep of 46 subjects (20 fit and 26 unfit) was assessed on nights following both exercise and non‐exercise conditions. The cycle length of fit subjects was found to be shorter than that of unfit subjects. However cycle length on a night following daytime exercise did not differ from that on a night following a no‐exercise day. We conclude that sleep cycle length is responsive to relatively long term variations in energy expenditure, but not day to day changes.
Pulse Transit Time and Blood Pressure: An Intensive Analysis
Authors: Lane James D. , Greenstadt Lisa , Shapiro David , Rubinstein Eduardo
Published: February 2007

Relationships between pulse transit time (PTT) and intra‐arterial systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP) were examined in 4 subjects under three conditions: rest, paced respiration, and mental arithmetic. PTT was measured from the EKG R‐wave to two peripheral pulses (brachial and radial) and from one pulse to the other. Three points on each pulse wave were used (peak, foot, slope) in the measurements, yielding nine different measures of PTT. The nine PTT measures were not consistently intercorrelated. PTTs initiated by the R‐wave were moderately correlated with SBP, but not with DBP or MAP. Brachial to radial PTTs were not correlated with any measures of BP. Relationships between PTT and BP also varied from subject to subject. The limited magnitude of the correlations and their inconsistency suggest caution in the simple substitution of PTT for beat‐to‐beat measures of BP.
Effects of Exhaustive Exercise on the Sleep of Men and Women
Authors: Bunnell David E. , Bevier Wendy , Horvath Steven M.
Published: February 2007

The effects of exhaustive exercise on sleep were examined in 5 women and 4 men who performed an acute bout of submaximal exercise (50–70% Vo2max) to the point of volitional exhaustion. Significant changes were observed in the quantity and temporal distribution of slow‐wave sleep (SWS) on the exercise night. The duration of SWS prior to rapid eye movement (REM) sleep onset increased markedly, along with a moderate increase in stage 4 and total SWS. REM sleep variables were affected in the early portion of the night, with an increased latency to first REM onset and a decrease in the duration of the first REM period. Initial REM cycle length (from first to second REM period onset) decreased as well. The magnitude of the SWS increase prior to REM onset was sex‐related, averaging 24 min for women and 5.7 min for men. A correlation of .85 was observed between this increase and total caloric expenditure during exercise for the women. Cardiovascular measures indicated significant elevations of heart rate and cardiac output during sleep on the exercise night. Analysis of urine samples revealed a significant drop in nocturnal cortisol excretion rates after exercise.

The results suggest that exhaustive exercise affects sleep primarily in the early portion of the night, inducing an increase in SWS pressure at the expense of REM sleep.
Thermistor Measurement of Male Sexual Arousal
Authors: Webster Jeffrey S. , Hammer David
Published: February 2007

Penile erection is accompanied by genital vasocongestion which increases penile skin temperature. These changes should be measurable using thermistors attached to the penis. The present study compared the UUT51J1 Uni‐Curve thermistor placed on the penis with the Barlow strain gauge in the assessment of sexual arousal in 8 heterosexual males. Sexual stimuli consisted of 3, 3‐min exposures to heterosexually explicit black‐and‐white videotapes. The results indicated that the two measures were highly positively correlated with each other and with self‐report. However, the strain gauge followed detumescence more closely than the thermistor and was more strongly correlated with subjective arousal. Also, the two probes differed as to when they reached peak response. The strain gauge typically reached its highest point prior to the end of the film, while the thermistor always peaked during the early post‐film interval. The thermistor's slow transition from temperature increases to decreases during the initial moments of detumescence appeared to be its principal shortcoming as a measure of male sexual arousal.
The Pharmacology of Human Information Processing
Authors: Callaway Enoch
Published: February 2007

A serial information processing model provides a rough but useful framework for studying effects of age and drugs on human cognition. Using this approach, one varies both the nature of experimental tasks and the biology of the subjects, and one measures both reaction time and event‐related potential latencies. For example, we may change a task by varying the complexity of the stimulus or the complexity of the response. We may change the biology of the subject by giving drugs or by using subjects of different ages. The interactions of the independent variables on reaction time and ERP latencies yield convergent data on the properties of information processing stages and on the actions of biological variables upon them. Using this approach we find that methylphenidate acts late on response‐related processes while aging acts on earlier and on stimulus‐related processes. A review of other studies shows the value of this approach, but is balanced by illustration of some of its problems and shortcomings.
Energy Expenditure During Response‐Dependent and Response‐Independent Food Delivery in Rats
Authors: Brener Jasper , Phillips Keith , Sherwood Andrew
Published: February 2007

Two groups of rats received food on variable‐interval schedules during SD but not during SΔ periods. Food delivery was contingent on running for Experimental subjects but independent of behavior for Controls. Contrary to predictions based on the energy maximization principle, Controls did not develop a more energy‐efficient behavioral adaptation than Experimentals. The contingency of food delivery influenced the SD/SΔ distributions of running (AMB) and oxygen consumption (OC) but not their overall rates. Overall OC and AMB rates appear to have been determined by the similar levels of food deprivation and rates of food delivery to which both groups were submitted. AMB was found to be a less conspicuous determinant of energy expenditure than the rate of food delivery which, it is argued, influenced OC by eliciting high‐energy consumatory activities. Although significant positive correlations between variations of heart rate (HR) and OC were observed in both groups, the HR/OC correlation was significantly weaker in the Control than in the Experimental group. This result is discussed in terms of the effects of the reinforcement contingencies on cardio‐somatic control.
Affective, Behavioral, and Avoidance Responses on the Visual Cliff: Effects of Crawling Onset Age, Crawling Experience, and Testing Age
Authors: Richards John E. , Rader Nancy
Published: February 2007

Two visual cliff experiments with human infants are reported that were designed to determine relationships among cardiac responses, avoidance and other behavioral responses, and developmental factors. The developmental factors considered were age at crawling onset, age at testing, and amount of crawling experience. In Experiment 1, infants were given either 30 or 60 days of crawling experience following crawling onset. In Experiment 2, infants were tested at either 9 or 12 months of age and crawling onset age was recorded. Infants were tested using a crawling avoidance procedure and the placing procedure that has been established for heart rate responses. Crawling onset age was the best predictor of avoidance behavior. Heart rate response was also a significant predictor of visual cliff avoidance, and was found to be related to testing age, especially for late crawlers. Looking down behavior was also found to distinguish crawling avoidance and crossing of the deep side of the cliff apparatus. These results, it is argued, suggest that fear is not the primary determinant of avoidance behavior on the visual cliff, but does contribute to avoidance at later ages.
Sudden Swimming Deaths: A Psychomotor Reinterpretation
Authors: Binik Yltzchak M. , Sullivan M.J.L.
Published: February 2007

Six experiments examine the determinants of survival in the sudden swimming death paradigm. It is argued that housing‐induced motor differences are a major determinant of survival. This conclusion is supported by comparing rats' performance in the swimming tank to their performance on other motor tasks, i.e., rotarod, passive avoidance, and open field. The deleterious effects of individual housing upon survival in the sudden swimming death paradigm can be reversed by giving animals access to running wheels. Little support could be found for “autonomic” or “critical period” explanations for sudden swimming deaths. Finally, mortality and behavioral differences between individually and socially housed animals are discussed from a motivational perspective.
Abdominal Temperature Changes During Male Sexual Arousal
Authors: Gayle Beck J. , Barlow David H. , Sakheim David K.
Published: February 2007

The present study explored the feasibility of using temperature measurement from a non‐genital location to assess sexual arousal. Based upon analyses conducted with thermographic techniques, it was hypothesized that abdominal skin cooling would occur during sexual arousal. In 2 sessions, 6 male subjects were shown low, moderate, and high arousing erotic films. Simultaneous measures of abdominal temperature, penile circumference, and subjective arousal were taken. Results indicate that while decreases in skin temperature were seen during arousal, thermister data did not correlate well with tumescence or subjective arousal ratings. It would appear that thermography and temperature measurement might be most fruitfully employed to explore basic physiological processes involved in sexual arousal, since continuous temperature measures do not appear sensitive enough for use in typical sex research paradigms.
Hemispheric Asymmetry for Word Perception: Behavioral and ERP Evidence
Authors: Bentin Shlomo , Feinsod Moshe
Published: February 2007

Reaction times (RTs) to words or patterns presented in the left or right visual fields and averaged Event‐Related Potentials (ERPs) evoked by the same stimuli presented foveally were measured separately. In both experiments, an oddball paradigm known to elicit the P3 component was used. Twenty‐four subjects (12 males) were tested in each experiment. In the electrophysiological study EEG was measured differentially from five different scalp sites, each referred to linked ear lobes. There were two frontal and two parietal lateralized electrodes, and a fifth which was located at the vertex (Cz).

The RTs to words were significantly delayed relative to the RTs to patterns. Furthermore, the responses were significantly shorter in the right visual field when the target was a word, yet only slightly shorter in the left visual field when the target was a nonsense pattern. The same pattern of results was found with the evoked potentials: A positive wave evoked by the target stimulus was measured at vertex with mean latency of 511.3 msec in the verbal task, and 464.4 msec in the nonverbal task. At the lateralized locations, a significant Task by Hemisphere interaction was found. When the target was a word the base to peak P3 amplitudes were higher over the left than over the right hemisphere. A reverse trend was found with nonverbal targets. The base to peak P3 amplitudes were slightly (but not significantly) higher over the right than over the left hemisphere.
Information and States of Motor Readiness: Their Effects on the Covariation of Heart Rate and Energy Expenditure
Authors: Sherwood Andrew , Brener Jasper , Moncur Douglas
Published: February 2007

Two studies are reported in which heart rate and oxygen consumption were monitored in rats during behavioral adaptation to avoidance conditioning tasks. In the first study, the provision of information regarding potential shock delivery for one group of animals led to them exhibiting a tendency toward increased behavioral efficiency compared with a low information group. The metabolic appropriateness of heart rate was assessed on the basis of a linear regression equation fitted to habituation data. During conditioning, both groups displayed heart rates that exceeded the predictions of this equation and, contrary to expectations, the group provided with additional information tended to display the more elevated heart rates. However, an interpretation of these effects was confounded by group differences in ambulation rates. Experiment 2 set out to test a specific hypothesis suggested by the results of the first experiment: that levels of metabolically elevated heart rates are directly related to motor preparatory states. Data in support of this hypothesis are presented, followed by a general discussion of the relationship between behavioral states and cardiovascular function.
The Effects of Initial Levels of Sweat Duct Filling and Skin Hydration on Electrodermal Response Amplitude
Authors: Edelberg Robert
Published: February 2007

The many problems encountered in efforts to demonstrate conformance of electrodermal responses with the Law of Initial Value have been thought by Lykken and Venables to stem in part from the operation of independent central and peripheral factors. This study was an attempt at separate examination of the peripheral determinants of initial value effects using animal preparations in which the central component was interrupted. Standard electrical stimuli to sympathetic nerves were used to assess the effect of various procedures calculated to change the hydration of the corneum or to change the initial level of sweat in the ducts. Drying of the corneum can cause a marked potentiation in SRR amplitude. Increase in initial degree of duct filling does likewise. These findings are consistent with a circuit model that emphasizes the shunting effect of the corneum on the contribution of ductal resistance changes to total resistance change. Effects on SCR amplitude are more complex. The complicating effect of immediately prior activity on initial value relationships calls for considerable caution in the design and interpretation of behavioral studies that involve electrodermal measurement.
REM and NREM Sleep Reports: Comparison of Word Frequencies by Cognitive Classes
Authors: Antrobus John
Published: February 2007

The difference between Sleep Stages 1 REM (rapid eye movement) and NREM (non REM) in reported dreaming is compared to several word frequency measures of characteristics of sleep mentation reports. Total Recall Frequency (total word frequency minus pauses, fillers, corrections, repetitions and commentary) discriminated REM from NREM with approximately the same strength as did global ratings of Dreaming. Although incremental repeated measures multivariate tests showed that each contributed some unique variance to the REM/NREM criterion, the unique portions were trivial in size. Frequencies of words that describe speech and visual imagery during sleep accounted for smaller portions of the REM/NREM variance. To the extent that a simple word frequency recall measure accounts for the same variance that such complex measures as dreaming and imagery share with REM/NREM, we may conclude that judges of Dreaming implicitly rely on a dimension similar to the Total Recall Freq. It is proposed that the cognitive difference between REM and NREM is essentially one of attention and memory. Given the high perceptual thresholds of REM sleep, the events attended to and stored in memory are necessarily unrelated to the surrounding environment and therefore differ from waking thought.
Psychophysiological Assessment of Statements About Pain
Authors: Salamy Joseph G. , Wolk David J. , Shucard David WM.
Published: February 2007

A psychophysiological procedure was developed to study the interaction of physiological activity and verbal statements in pain patients. This procedure compared skin potential and heart rate changes occurring during designated baseline, anticipation, reception, processing, and responding stages of a question‐answer sequence, in 7 chronic pain patients and 7 non‐patient controls. Pain, emotional, and neutral type questions were randomly presented. It was found that the processing of pain questions produced significantly larger physiological changes in pain patients than in the non‐pain controls. Such differential psychophysiological responsivity may serve as a basis for the early recognition of chronic pain syndrome and the detection of malingering.
Psychopathy and Selective Attention During Performance of a Complex Perceptual‐Motor Task
Authors: Jutai Jeffrey W. , Hare Robert D.
Published: February 2007

Autonomic and electrocortical activity were recorded while prison inmates with high (H) and low (L) ratings of psychopathy were presented with a series of binaural tone pips, either by themselves (passive attention) or while video games were being played (selective attention). During selective attention the subjects were told that the tone pips were irrelevant to the primary task, the video games. The N100 component of the auditory evoked potential was used as an index of attention paid to the tone pips, while performance on the video games was considered to be a reflection of attentiveness to the primary task. There were no group differences in N100 amplitude or latency during passive attention, supporting the results from several previous studies. During selective attention Group H gave small N100 responses to the tone pips during each video game trial, including the first one, while Group L gave large N100 responses to the tone pips during the first trial, and small responses during later trials. Both groups performed equally well during the first few trials, but while the performance of Group L continued to improve, that of Group H deteriorated over the last few trials. The results were interpreted in terms of limited capacity models of attention, and provided some support for the hypothesis that psychopaths allocate a relatively large proportion of their attentional resources to things of immediate interest, effectively ignoring other stimuli.
Recovery of Performance During Sleep Following Sleep Deprivation
Authors: Rosa Roger R. , Bonnet Michael H. , Warm Joel S.
Published: February 2007

Very few studies have systematically examined recovery of performance after sleep deprivation. In the present study, 12 young adult males were sleep deprived for periods of 40 and 64 hrs. Each period was preceded by baseline nights of sleep and followed by two recovery nights of sleep. Immediate recall and reaction time were tested at 2300, 0145, 0400, 0615, and 0830 during baseline, deprivation, and recovery nights. Performance efficiency showed a progressive decline after 2 hrs of recovery sleep following both periods of deprivation. Return to baseline was apparent after 4 hrs of steep following 40 hrs awake and after 8 hrs of sleep following 64 hrs awake. These results suggested that, in terms of behavioral efficiency, an equal amount of sleep is not required to compensate for sleep lost.
The Effects of Directional Facial Cues on Electrodermal Conditioning to Facial Stimuli
Authors: Dimberg Ulf , ÖHman Arne
Published: February 2007

The present two Experiments demonstrate that the orientation of angry facial expressions is a critical cue when faces serve as conditioned stimuli during aversive electrodermal conditioning. Experiment 1 demonstrated that responses conditioned to angry faces directed toward the subjects showed significant resistance to extinction whereas responses conditioned to angry faces directed away extinguished immediately during extinction. Experiment 2 was designed to investigate whether the orientation factor was effective only during extinction, i.e. whether the orientation was a performance variable, or if the observed effect originated from factors active during acquisition, i.e. if the orientation primarily influenced learning. When the orientation was shifted between the acquisition and the extinction phase, it was found that it did not matter what direction the faces had during acquisition; it was only during extinction that the faces needed to be directed toward the subjects to evoke persistent responding. These results suggest that the subjects acquired a conditioned response to the angry face regardless of its direction, but that this learning effect remained only when the angry face was directed toward the subject during extinction.
Opto‐Electronic Belts for Recording Respiration in Psychophysiological Experimentation and Therapy
Authors: Strasburger Hans , Klenk Dieter
Published: February 2007

A temperature‐compensated and a simpler, non‐compensated respiration measuring belt based on an infrared light sensing principle are described. The systems are designed to overcome shortcomings in usual respiration monitoring methods applicable to: 1) a respiratory‐sinus‐arrhythmia quantification study, and 2) a portable circulation monitoring system. Both devices have a rugged and lightweight construction, are comfortable for subjects, relatively free from artifacts, are of low cost, and are simply interfaced to recording apparatus. Additionally, the temperature‐compensated version allows for DC‐recording, permitting monitoring of breath‐holding, which is not feasible with conventional transducers. The simple construction of the non‐compensated version makes it especially suitable to routine therapy and monitoring applications. Use of two temperature‐compensated belts measuring thoracic and abdominal circumference allows for breath‐volume calibration by multiple linear regression with reliabilities between 75 and 95%. The mathematical basis for this calibration procedure is discussed in detail.
Dependence of Skin Conductance Reactions and Skin Resistance Reactions Upon Previous Level
Authors: Boucsein Wolfram , Baltissen Ruediger , Euler Manfred
Published: February 2007

When results from an earlier investigation of skin resistance reaction and skin conductance reaction taken from parallel sites were reanalyzed, a surprising discrepancy between these measures was noted. At high levels of noise stimuli (90dB and above), skin resistance reaction amplitudes decrease with the number of trials whereas skin conductance reaction amplitudes increase. This divergence can be understood in terms of level dependence of both skin conductance reaction and skin resistance reaction. Because of opposite trends in resistance and conductance level shifts in the course of the experiment, skin resistance reaction measures yield decreasing values, even if the “true” reaction were constant, whereas SCR measures tend to overestimate the reaction. After a correction based upon empirically‐determined level dependence the two measures give comparable results.

Theoretical considerations underlying the empirical correction procedures are discussed based upon a simple electrical model of the skin, and recommendations are made for use of AC measurement in electrodermal activity research.
Forearm Blood Flow Responding Prior to Voluntary Isometric Contraction
Authors: Roberts Richard J. , Weerts Ted C.
Published: February 2007

Srain‐gauge plethysmography was used to study phasic forearm blood flow (FBF) responding, which has been presumed to occur in human subjects prior to voluntary muscular contraction. In a two‐group design, 10 subjects performed a 7‐s, fixed‐foreperiod, reaction‐time (RT) task in which static handgrip was the required RT response; 10 additional subjects in a High Incentive (HI) condition performed a more stressful delayed avoidance task. Bilateral FBF and HR were computer‐sampled over the preparatory interval (PI) and transformed into second‐by‐second measures. Mean FBF estimates were also obtained by averaging over the entire PI. HI subjects were found to manifest significantly greater mean FBF prior tro motor responding than did subjects performing the nonstressful RT taks. Such preparatory FBF responding was task‐specific, occurring only in the Arm to be performing the signalled RT response. Furthermore, this task‐specific, phasic increase in averaged mean FBF was observed to occur in subjects' left and right arms. Trend analysis and visual inspection of second‐by‐second FBF waveforms demonstrated a gradual decline in flow rate over the course of the preparatory interval under all experimental conditions. HR responding manifested the characteristic triphasic waveforms, with higher heart rate and augmentation of acceleratory and terminal deceleratory components exhibited by the HI group. the findings suggest that human phasic FBF responding can be influenced by motoric and motivational factors as well as by demands for sensory intake behavior.
Behavioral Control of Respiration in Sleep
Authors: Badia Pietro , Harsh John , Balkin Thomas , Cantrell Peggy , Klempert Allen , O'Rourke Diane , Schoen Lawrence
Published: February 2007

Three experiments are presented involving behavioral control of sleeping respiration during all‐night sleep recording. Probability and latency of the breathing response to an auditory signal revealed that control over sleeping respiration was obtained in all sleep stages and was maintained over several nights. This control was especially marked when failure to respond was punished (contingency procedure) by increasing the intensity of the signal (Experiments 2 and 3). Few awakenings occurred to the signal but signs of brief arousal (bursts of alpha activity, increases in EMG activity, EEG “speeding”) often accompanied the behavioral response. Overall sleep patterns were only minimally disrupted by the procedure. Demonstrating behavioral control over sleeping respiration may be a promising step toward the development of behavioral therapies for certain sleep apnea disorders and hypoventilation syndromes.
Effects of Behavioral Control and Type A Behavior on Cardiovascular Responses
Authors: van Schijndel Martin , De Mey Hubert , Näring Géerard
Published: February 2007

The purpose of this study was twofold: (a) to examine the relationship between degree of behavioral control and cardiovascular changes in 60 adult males performing an anagram solution task, and (b) to assess the interaction between behavioral control and type of subject (A vs. B). Three conditions were used, differing from each other in the percentage of solvable anagrams (100, 50, and 30%). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before, during, and after the anagram task. In all conditions, during‐task SBP, DBP, and HR were significantly elevated above baseline. Blood pressure (BP) elevations appeared to be curvilinearly related to degree of behavioral control, i.e., more elevated in the 50% than in the 100% and 30% conditions. HR changes did not differ among conditions. Concerning the Type A behavior pattern, the results revealed significantly greater BP elevations for Type A than for Type B subjects, especially in the 50% condition, thereby confirming that the physiologic correlates of Type A behavior are predominantly evoked in challenging circumstances. Findings were discussed in the light of results of cardiovascular and endocrinological research. Consideration was given to the possible role of disengagement in the 30% condition and to differences in the pattern of responding between As and Bs.
Task Difficulty, Type A Behavior Pattern, and Cardiovascular Response
Authors: Contrada Richard J. , Wright Rex A. , Glass David C.
Published: February 2007

Forty‐one young male subjects performed either an easy or moderately difficult arithmetic task with the opportunity to earn a monetary incentive if they did well. Cardiovascular (heart rate, systolic and diastolic blood pressure) and subjective responses were assessed immediately prior to and 5 min following task performance. Results indicated greater systolic (SBP) responses during the Pre‐task period for subjects expecting to perform the difficult task. Behavior pattern classifications based on the Jenkins Activity Survey revealed Higher Pre‐task heart rate (HR) elevations among Type As compared to Bs in the Difficult task condition, and greater Pre‐task SBP responses in As compared to Bs irrespective of task difficulty. There also was some evidence of an association between SBP reactivity and scores on the Thurstone Activity scale. Change‐scores reflecting SBP and HR reactivity were correlated in the Pre‐task period of the Difficult but not the Easy condition. Predictions regarding the impact of motivational arousal upon goal attractiveness were not supported, possibly for methodological reasons.
On P300 Latency and Correlational Inference
Authors: Polich John
Published: February 2007

The use of statistical correlations to determine the underlying relationships between P300 latency, memory function, and aging is discussed. Similar correlational patterns obtained over a variety of subject populations can strengthen inferences about the specific associations among these variables. Partial correlation techniques can facilitate such inferences only when all factors are linearly related.
Thyroid Function in Normals: Influences on the Electroencephalogram and Cognitive Performance
Authors: Tucker Don M. , Penland James G. , Beckwith Bill E. , Sandstead Harold H.
Published: February 2007

Recently it has been suggested that thyroid function may influence neuropsychological processes not only as a result of thyroid disease but also through normal neurophysiologic adaptive mechanisms. In 69 normal university students, levels of thyroid stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3) were assayed in blood samples and related to measures of cognitive performance and to spectral measures of the EEG recorded during cognitive performance. Significant relationships were found between T3 levels and delta power in the EEG from occipital leads, with higher T3 associated with less EEG power in the left hemisphere and greater power in the right hemisphere. Higher T3 levels were associated with poorer performance on several cognitive tasks, particularly for males, although the males with higher T3 levels also showed faster correct responses on a word fluency task. These results seem to support the hypothesis that an individual's characteristic level of thyroid function is relevant to normal neuropsychological processes.
Finger Pulse Volume as a Measure of Anxiety in Response to Evaluative Threat
Authors: Smith Timothy W. , Houston B. Kent , Zurawski Raymond M.
Published: February 2007

Previous research has validated finger pulse volume (FPV) as a measure of anxiety in response to threat of physical harm. The present study evaluated FPV as a measure of anxiety in response to a social‐evaluative threat. Physiological and self‐report measures of anxiety were recorded while subjects anticipated and responded to an interview in either high or low stress conditions. Results indicated that FPV was sensitive to the stress manipulation during both periods and was correlated with self‐reported anxiety during the anticipation period. The findings were discussed in terms of FPV as a physiological index in the assessment of anxiety.
Facilitated Recall Following RFM And NREM Naps
Authors: Schoen Lawrence S. , Badia Pietro
Published: February 2007

A novel procedure was used to assess (a) the differential effects of REM and SWS on retention and (b) whether these sleep stages enhanced recall for different types of information. In a 2 × 2 factorial design, subjects were given non‐meaningful and meaningful verbal learning tasks. Learning took place either early in the morning or late in the afternoon. Following learning subjects either slept or remained awake for a 2‐hr retention interval, after which recall was assessed. Sleep for morning subjects was composed of stages 1, 2 and rapid eye movement sleep while sleep for afternoon subjects was composed of stages 1, 2 and slow wave sleep. Retention for both tasks was better following periods of sleep than following periods of wakefulness but no differences in recall were observed after REM vs. NREM naps.
Bilateral Electrodermal Activity During Differential Cognitive Hemispheric Activation
Authors: Fedora Orestes , Schopflocher Donald
Published: February 2007

In an attempt to reconcile inconsistent results reported to date, 27 dextral males were administered two separate procedures to examine the effects of hemisphere‐specific cognitive tasks on bilateral electrodermal activity. The first procedure used arithmetic problems and slide visualizations to activate the left and right hemispheres respectively; the second procedure used aural proverbs and visualization problems. Neither procedure produced the expected electrodermal response magnitude asymmetry across tasks. While the potential effects of uncontrolled variables are discussed, these results question the robustness of the relationship between differential hemispheric activation and asymmetric electrodermal response magnitudes.
Phasic T‐Wave Amplitude and Heart Rate Changes as Indices of Mental Effort and Task Incentive
Authors: Scher Hal , Furedy John J. , Heslegrave Ronald J.
Published: February 2007

The sensitivities of T‐wave amplitude (TWA) and heart rate (HR) to manipulations of the mental effort (ME) and incentive associated with performance of the backward digit span task were investigated. The experimental task was so chosen because it could be administered without requiring subjects to speak during its performance, thus minimizing the intrusion of respiratory and motor artifacts. The ME required during task performance was manipulated by varying the number of digits presented, creating Hard and Easy trials. The incentive for subjects to perform well was varied by the threat of the delivery of a noxious noise stimulus, which was ostensibly contingent upon adequate performance on some (Test) but not other (Practice) trials.

TWA attenuation and HR acceleration were greater on the Hard as compared to the Easy Trials, and on the Test as compared to the Practice trials. No interactions between the ME and Incentive factors emerged for either cardiac variable. These results suggest that the effort and the incentive of subjects during mental work may be indexed reliably by phasic changes in TWA and HR. The conjoint use of these two cardiac measures may also elucidate the involvement of the two autonomic branches during task performance.
On‐Line Minicomputerized Measurement of Cardiopulmonary Function On a Breath‐By‐Breath Basis
Authors: Langer Alan W. , Hutchenson J. Stanford , Charlton John D. , McCubbin James A. , Orist Paul A. , Stoney Catherine M.
Published: February 2007

An on‐line minicomputer‐based system for determining breath‐by‐breath respiratory gas exchange (oxygen consumption and carbon dioxide production), ventilation (tidal volume, respiratory period, and minute ventilation), partial pressures of end‐tidal oxygen and carbon dioxide, and heart rate is described. The system software includes routines for calibration, signal acquisition and processing, and disk storage of breath‐by‐breath data. The software is written in Fortran IV and runs under Digital Equipment Corporation's RT‐11 system monitor. On‐line (real time) computations of breath‐by‐breath data include instantaneous corrections of: 1) expired gas flow for alterations in gas viscosity, and 2) expired gas fractions for gas analyzer response characteristics. Additional programming provides rapid data reduction and averaging over a user‐selected time base. Twelve healthy male volunteers were monitored at rest and during 10‐min bouts of exercise at 300, 600, and 900 kpm · min‐1, and during recovery. Both the transient and steady state alterations in cardiopulmonary response to these exercise tests were found to compare favorably with standard values established in the exercise physiology literature. The sensitivity and accuracy of this method to monitor both phasic and tonic alterations in cardiopulmonary function during stress underscores its suitability for a wide range of psychophysiologic applications.
Chronic Sleep Reduction: Daytime Vigilance Performance and EEG Measures of Sleepiness, With Particular Reference to “Practice” Effects
Authors: Horne J.A. , Wilkinson S.
Published: February 2007

Six pairs of young adult 8‐hr sleepers were divided equally into two groups, Reduction (R) and Control (C). They adhered to strict bed and arising times for six weeks. Additionally, R subjects reduced their sleep systematically to an average of 6 hrs per night. Following a baseline week, and on a weekly basis, “yoked” pairs of subjects, one from each group, were assessed for daytime sleepiness during prolonged vigilance performance, and by EEG measurement. All‐night sleep EEGs were taken on R subjects before and at the end of the reduction. There were no significant differences between the groups for any of the daytime sleepiness measures, but both groups displayed significant “practice” effects over the weeks. R subjects experienced no major difficulties, except for some tiredness around awakening and lunchtime. Overall daytime sleepiness was not increased. Reduction was at the expense of REM and stage 2 sleep, and led to significant declines in sleep onset latency and in stages W + 1 at nighttime. SWS was not affected. This level of reduction in young adults seems to be achieved relatively easily.
Stability of Pathway‐Hemisphere Differences in the Auditory Event‐Related Potential (ERP) to Monaural Stimulation
Authors: Connolly John F.
Published: February 2007

The evidence for ERP manifestations of contralateral dominance in the auditory pathways is not entirely compelling. The effect when found has involved either latency or amplitude of a variety of components obtained from averaged or subtraction waveforms. Also, the effect appears to have as much to do with hemisphere as pathway differences. The objectives of this experiment were to establish whether a specific ERP peak reflected contralateral dominance, to assess its long‐term stability, and to clarify the apparent pathway‐hemisphere interactions which result from monaural stimulation. Ten male subjects were tested on 6 occasions (generally weekly intervals). On each occasion, 76 monaural tones were presented while EEG was recorded at C2, P2, T3, and T4 referred to linked earlobes. P70, N120, and P200 peak amplitudes and latencies and N1–P2 amplitudes were examined. N120 amplitudes proved to be larger at the temporal site contralateral to the ear stimulated. This contralateral dominance effect was observed on all 6 occasions for right ear stimuli and on all but one occasion for left ear stimuli. N1–P2 amplitudes less reliably reflected contralateral dominance because possible hemisphere effects appeared with this measure. Methodological issues related to assessment of ERP contralateral dominance and to the variety of effects seen in the literature are discussed. The data are examined with reference to neurophysiological substrates thought to underlie auditory ERPs. Finally, the utility of a stable ERP phenomenon in assessing drug or pathology effects is evaluated.
Heart Rate Deceleration in REM Sleep: An Orienting Reaction Interpretation
Authors: Taylor W.B. , Moldofsky H. , Furedy J.J.
Published: February 2007

Eye‐bursts (EBs) in REM sleep are associated with “active'’dream reports. Heart rate (HR) and T‐wave amplitude (TWA) were studied during EBs, quiescent intervals (Q), and pre‐EBs in REM sleep of 18 normal subjects. A clear and significant HR deceleration (HRD) emerged, which began 3 seconds before eye‐bursts, but there were no coincident changes in TWA. Assuming EBs to be an instance of stimulus intake, the psychological interpretation of these phasic HRDs is that they are attentional orienting responses. Moreover, if TWA reflects predominantly sympathetic myocardial influence, then the absence of EB‐asssociated TWA changes may suggest a vagal rather than sympathetic physiological mechanism.
Blood, Sweat, and Tears: Individual Differences in Autonomic Self‐Perception
Authors: Katkin Edward S.
Published: February 2007

This paper analyzes the role of autonomic activity and its perception in the experience and expression of emotion. A series of experiments is described in which an objective methodology for the assessment of heartbeats is developed and used to test a variety of hypotheses about the relationships among heartbeat perception, arousal, and emotion. The data indicate that there are substantial individual differences in the ability to learn to detect heartbeats. Primary among these individual differences is gender–males appear to learn the discrimination more readily than females. Further, when arousal is induced either by physical or psychological stimuli, accuracy of heartbeat detection is increased. The accuracy of heartbeat detection is also related to self‐report of affective experience, and may be subserved by functions of the right cerebral hemisphere. The role of cardiodynamics in heartbeat perception is also discussed.
Behavioral Genetic Approaches to Psychophysiological Data
Authors: Boomsma Dorret I. , Gabrielli William F.
Published: February 2007

Behavioral genetic techniques have been developed to study the genetic and environmental contributions to individual differences in behavior, including covariances between different types of behaviors and stability of behaviors. Several studies have shown that certain psychophysiological characteristics appear to have heritable components. Therefore, it would seen appropriate that behavioral genetic techniques should be generalized for application to psychophysiological data. After reviewing general behavioral genetic methodology, this paper summarizes classical and new biometrical genetic techniques for both univariate and multivariate analyses, suggesting how these techniques are appropriate for the study of psychophysiological data and the relationship between psychophysiological variables and behavioral measures
Heart Rate and Oxygen Consumption during Mental Arithmetic, a Video Game, and Graded Exercise: Further Evidence of Metabolically‐Exaggerated Cardiac Adjustments?
Authors: Turner J. Rick , Carroll Douglas
Published: February 2007

Heart rate, plus various metabolic and ventilatory indices, were monitored while 20 young male subjects were exposed to a video game and a stressful mental arithmetic task. Measurements were also made while subjects undertook graded isotonic exercise. All measures changed as a function of psychological challenge, and during exercise physiological activity increased as an orderly function of workload. For each subject, heart rate was plotted against oxygen consumption over the various exercise loads. For the majority of subjects the analogous data points for the video game and mental arithmetic lay reliably above the exercise heart rate‐oxygen consumption regression lines. When these regression lines were used to predict heart rate values during psychological challenge, the predicted values were significantly less than the values actually recorded for both tasks; although the discrepancy between predicted and actual values was on average greater with mental arithmetic, the difference was not statistically reliable. Pre‐stressor baseline conditions were also associated with heart rate levels greater than predicted, albeit to a lesser extent. Finally, while both stressors produced heart rate adjustments additional to expectancies, inter‐task consistency was low.
The Effects of Discrimination Training on Voluntary Control of Cephalic Vasomotor Activity
Authors: Fudge Ronald , Adams Henry E.
Published: February 2007

The present study was conducted to test Brener's calibration theory of visceral learning. It was hypothesized that training in discrimination of cephalic vasomotor responses would enhance acquisition of voluntary and biofeedback control of cephalic vasomotor response. Four groups were given discrimination training to detect either constriction, dilation, both constriction and dilation, or given false feedback. All groups were then given biofeedback training in constriction. All groups were assessed on discrimination accuracy, acquisition of biofeedback control of constriction, and voluntary control of dilation and constriction.

The results indicated that discrimination of cephalic vasomotor responses can be learned and that this skill facilitates the acquisition of biofeedback and voluntary control of vasomotor responses. This facilitation occurs only if discrimination training is given for the specific response to be learned. The data suggest that discrimination of the relevant response is a necessary but not sufficient condition for acquisition of voluntary control in biofeedback learning.
Relationship Between Stimulus Intensity and the P300
Authors: Papanicolaou Andrew C. , Loring David W. , Raz Naftali , Eisenberg Howard M.
Published: February 2007

The effect of stimulus intensity on the P300 component of the averaged auditory evoked potential was examined in healthy young adults. Although no effect on P300 amplitude was present, increasing loudness was inversely related to P300 latency. These data demonstrate a partial dependence of P300 on stimulus parameters, and underscore the importance of determining the hearing ability of subjects and patients in studies employing P300 as an index of information processing speed.
P300 and S‐R Compatibility: A Reply to Magliero et al.
Authors: Ragot Richard , Renault Bernard
Published: February 2007

Some recent papers have been devoted to simultaneous analysis of RT and P300 latency effects with S‐R compatibility. This, indeed, can be particularly fruitful since it may provide some insight into response choice, a crucial stage of information processing taking place between stimulus analysis and response production. Apparent contradictions have arisen between these studies because of the different kinds of S‐R compatibilities involved. The aim of this reply is to emphasize the discrepancies between experimental designs that use semantic versus spatial compatibilities.
Semantic, Evaluative, and Self‐Referent Processing: Memory, Cognitive Effort, and Somatovisceral Activity
Authors: Cacioppo John T. , Petty Richard E. , Morris Katherine J.
Published: February 2007

Twenty‐six subjects performed orthographic, grammatical, evaluative, and self‐referent orienting tasks. During each trial, integrated facial and forearm EMG activity, HR, and T‐wave amplitude were monitored; following each trial, response latency and either reported task difficulty (Replication 1) or cognitive effort (Replication 2) were assessed; and recall was assessed at the conclusion of the session. Recall was poorest when words were judged in terms of their orthographic appearance, moderate when words were judged in terms of their grammatical or evaluative features, and best when words were judged for their self‐descriptiveness, even though response latency was longest and reported effort was greatest for the grammatical task. Results also revealed that somatovisceral responses varied across tasks, with clear differences emerging between semantic and nonsemantic processing and between evaluative and self‐referent processing. Results suggest that cognitive effort, rather than encoding efficacy, influences task‐evoked somatic responses.