bluuebunny/crossref_metadata_2025 huggingface dataset:
For Distinguished Early Career Contribution to Psychophysiology: Award Address, 1985
Authors: Johnson Ray
Published: February 2007

A model of P300 amplitude is proposed that reduces the many hypothetical constructs invoked to explain variations in P300 amplitude to three dimensions: 1) Subjective Probability, 2) Stimulus Meaning, and 3) Information Transmission. Evidence is presented to support the assertion that variables on the subjective probability and stimulus meaning dimensions have independent and additive contributions to overall P300 amplitude. The amplitude contributions of both of these dimensions, however, are modulated by a multiplicative relation with the proportion of transmitted stimulus information. Within each dimension, the fundamental experimental variables and their interrelations are specified. An example is presented to show how, by using an additive factors method, the respective amplitude effects of the probability and stimulus meaning dimensions can be separated. Supporting data are presented to show that the proposed model provides a reasonable and testable framework in which to conceptualize P300 results.
Effects of Arousal on Habituation of Electarodermal versus Vasomotor Responses
Authors: Goldwater Bram C.
Published: February 2007

While there is considerable evidence (hat habituation of electrodermal responses is retarded under conditions of heightened arousal, less work has been done on vasomotor responses. A few studies have, however, suggested that arousal has the opposite effect on vasomotor responses, producing an acceleration of habituation In this case. The present study compared skin conductance (SC) and finger pulse volume (PV) responses to a series of tone stimuli under conditions of “high arousal” (HA)‐where subjects were standing during testing‐and “low arousal” (LA)‐where subjects were seated. Tonic measures confirmed that the experimental manipulation was effective in raising SC level and nonspecific activity and lowering PV level in the HA relative to the LA condition. Significant Group (HA vs. LA) X Measure (SC vs. PV) interactions for response frequency and number of trials to habituation were consistent with the prediction that arousal exerts differential effects upon habituation in the two response systems. These data provide further challenges to theories based on unitary models of autonomic response mechanisms.
An Evaluation of Different Techniques for Removing Eye‐Blink Artifact from Visual Evoked Response Recordings
Authors: O'Toole Dennis M. , Iacono William G.
Published: February 2007

This investigation compared four methods used to control eye‐blink artifact in visual evoked response (VER) recordings using the augmenting‐reducing paradigm: rejecting trials containing blinks, presenting the stimuli through closed eyelids, and two different techniques for subtracting a proportion of the averaged electro‐oculogram (FOG) from the averaged VER. The two subtraction procedures differed in the way in which they estimated the amount of EOG to be subtracted and in the case with which they could be applied. Twenty normal, female subjects were exposed to a series of four different intensity light flashes twice with eyes open and once with eyes closed. Blinking was monitored by recording the EOG and EEG was recorded from three midline electrodes. The results indicated that the two subtraction techniques were very similar. They effectively removed ocular artifact and produced corrected VERs that showed high retest stability. Presenting the flashes through closed lids yielded idiosyncratic data, and rejecting trials contaminated by blinks was found to have limited utility with the VER paradigm used in the present study.
Behavioural Energetics: Some Effects of Uncertainty on the Mobilization and Distribution of Energy
Authors: Brener Jasper
Published: February 2007

Several sets of data illustrating dissociation of metabolic and muscular work rates are presented. During response acquisition, the rate of energy expenditure declines although work rates remain constant and goal achievement increases. When higher response costs are demanded for goal achievement, work rates increase whereas energy expenditure remains constant. Decreases in outcome probability also give rise to increases in motor intensity and work rate but do not influence the rate of energy expenditure. It is proposed that behaviourally‐related variations in metabolic rate are influenced by environmental uncertainty (“what to do”), whereas variations in the intensity of motor output are influenced by response uncertainty (“how to do it”). The processes of response selection which provide the means by which response uncertainty is resolved, activate motor channels for the expression of energy mobilized by the prevailing state of environmental uncertainty.
A Passive Behavioral Measure of Sleep Onset in High‐Alpha and Low‐Alpha Subjects
Authors: Perry Thomas J. , Goldwater Bram C.
Published: February 2007

Polygraph recordings were conducted with normal subjects who were not sleep‐deprived lo examine the association between EFG alpha dynamics and a passive behavioral index of sleep/ wake status, and to assess the usefulness of that index in subjects who do not produce abundant wakeful alpha activity. I In‐ behavioral indicator of sleep unset comprised the depression of a telegraph key initialed by loss of extensor tension in the finger. Alpha abundant (high‐alpha) subjects showed a strong association of alpha level (as sleep Stage Wake (w) vs. Stage I sleep) with behavioral level, and a strong association of alpha loss events with key closure events. Mean latencies between alpha loss and key closure varied from ‐ 1.8 to 18.4 s with a median of 1.0 s. As expected, high‐alpha subjects also showed significant correlations between alpha level and changes in peripheral physiological variables in the vicinity of sustained alpha losses. Compared with Stage W. Stage 1 was associated with a greater incidence of slow eye movements, lower abdominal breathing amplitude, and a higher thoracic:abdominal breathing ratio. Similar correlations were observed in both high‐alpha and low‐alpha subjects between these variables and the key index, supporting its potential generality as an indicator of sleep onset.
The Sleeping Rat Shows Signs of Orienting Response to Neutral Stimuli
Authors: Johnen Marga
Published: February 2007

Cortical arousal, cardiac response, and body movement to auditory stimuli were studied during slow wave sleep (SWS) of the rat. Rats were exposed to sequences of 10 tone pulses of a frequency of 16 kHz, a sound pressure level of 60dB, and n duration of 2 s (Experiment I) or 10 s (Experiment II). Repeated stimulus presentations permitted the evaluation of short‐term habitation. Similar results were found in both experiments, i.e. habitation of the cortical arousal response and of the phasic cardiac deceleration to stimulus onset and offset. With repeated presentations, cardiac acceleration showed a less regular course than cardiac deceleration and cortical arousal. Subsequently presented tone pulses of 80dB did not result in a recovery of the habituated response. Cardiac deceleration and cortical arousal on the one hand, and cardiac acceleration and motor activity on the other hand, were strongly correlated. The results are compared with human studies.
Heart Rate Acceleration and its Relationship to Total Serum Cholesterol, Triglycerides, and Blood Pressure Reactivity in Men with Mild Hypertension
Authors: Jorgensen Randall S. , Nash John K , Lasser Norman L. , Hymowitz Norman , Langer Alan W.
Published: February 2007

This study investigated heart rate (HR) acceleration and its relationship to serum cholesterol, triglycerides, and blood pressure reactivity in a group of men with unmedicated mild hypertension. Each man's cardiovascular responses were monitored as he performed the Stroop Color Word Interference test and played the Pac Man Videogame. In comparison to their low HR accelerator counterparts, high HR accelerators manifested greater systolic and diastolic blood pressure responses during behavioral challenge. Moreover, high HR accelerators exhibited higher levels of serum cholesterol and triglycerides than low HR accelerators, even though these determinations were made from blood drawn during the clinic visit that preceded the clinic visit where cardiovascular reactivity was assessed. Heart rate acceleration and its positive association with serum lipids, as well as its role as a potential individual difference relevant to the profiling of persons at greater risk for the development of atherosclerosis were discussed.
Bilateral Electrodermal and Electrocortical Activity in Anticipation of Sensorimotor Tasks
Authors: Rockstroh Brigitte , Elbert Thomas , Lutzenberger Werner , Birbaumer Niels , Roberts Larry E.
Published: February 2007

The present study investigated the relationship between lateralized sensorimotor activation and lateralized elevation of electrodermal activity. Within a two‐stimulus reaction time paradigm skin conductance responses (SCRs) were recorded from both hands, while subjects awaited and performed unilateral sensorimotor tasks. A tactile warning stimulus was applied 6 s prior to a tactile imperative stimulus either to the same or to the contralateral hand; the imperative stimulus was associated with a choice reaction time task.

Task‐dependent lateral asymmetry with larger skin conductance responses contralateral to the involved hemisphere indicated contralateral facilitatory processes rather than inhibition. This asymmetry disappeared with repeated stimulation (across trials). Only right‐hand (left hemispheric) tasks proved to be sensitive to habituation.

The asymmetry, recorded in slow brain potentials (SPs), assured that lateralized cortical processing was induced through the present experimental arrangement. The brain potentials specified the time course of lateralized processing, exhibiting larger late negative shifts at the precentral areas contralateral to the hand involved in the sensorimotor task and larger early negativity and a more pronounced positive evoked potential (late positive complex, LPC) contralateral to the hand stimulated by the tactile warning stimulus.
A Comparison of Additional Heart Rates During Active Psychological Challenge Calculated From Upper Body and Lower Body Dynamic Exercise
Authors: Turner J. Rick , Carroll Douglas , Hanson Jane , Sims Jane
Published: February 2007

Heart rate, oxygen consumption, and blood pressure were recorded while 22 young males performed a stressful mental arithmetic task and played a video game. Measurements were also made while subjects undertook two separate graded dynamic exercise tasks, an upper body and a lower body task. All measures changed as a function of psychological challenge, and during exercise heart rate and oxygen consumption changed as an orderly function of workload. For each subject, heart rate was plotted against oxygen consumption over the various workloads for each exercise task separately, thereby generating two regression lines per subject. In conjunction with oxygen consumption values during the psychological tasks, these regressions allowed the prediction of expected heart rate values during psychological challenge, and thus the computation of additional heart rate as the difference between actual heart rate and predicted heart rate. Actual heart rate during psychological challenge was substantially greater than predicted heart rate, i.e., there was considerable additional heart rate. This was the case irrespective of whether upper or lower body exercise was used to compute the predictions, and there was no significant difference between the additional heart rates generated from the two exercise tasks, which produced regression lines with similar slope and intercept values.
Novel Approaches to the Problem of Latency Jitter
Authors: Möucks Joachim , Köuhler Walter , Gasser Theo , Pham Dinh Tuan
Published: February 2007

This paper deals with the issue of variable latencies of single potentials. A new method is proposed for obtaining estimates of single latency shifts, which allows furthermore a statistical test on the presence of latency jitter. In the Appendix, we give a precise description of the algorithmic procedure in order to allow an implementation of the new approach. A simulation study using real data from 41 children demonstrated that the procedure performed much better than the familiar Woody algorithm which produced highly unstable estimates. The new statistical test on presence of latency jitter was validated and also evaluated using simulations. The test was specifically sensitive to latency jitter but not to other types of variation of single potentials. In an application of real flashevoked potentials evidence for the presence of variable latencies was found.
Computerized Cardiovascular Monitoring: Method and Data
Authors: Linden Wolfgang , Estrin Ronald
Published: February 2007

This paper describes the development of a digitized, real‐time, microcomputer‐based signal processing system which records the following variables: systolic and diastolic blood pressure, heart rate, pulse transit time, blood volume pulse, and R‐, S‐, and T‐wave amplitudes of EKG signals. Forty‐eight healthy subjects participated in a three‐task stress response study in order to gather initial data for evaluating the reliability and validity of this monitoring system. The three tasks represented replications of earlier studies: 1) reading aloud of a monotonous neutral text (Reading Only, RO); 2) mental arithmetic without vocalization (Arithmetic Quiet, AQ); and 3) mental arithmetic with vocalization (Arithmetic Aloud, AA). The findings provided support for the reliability and validity of the new monitoring system given that few data were lost, and resting values as well as differential task responses were found to be comparable with earlier data sets derived via similar experimental protocols.
Relation of Learned Heart Rate Control to Self‐Report in Different Task Environments
Authors: Williams Robert J. , Roberts Larry E.
Published: February 2007

A widely‐expressed view based on early studies of the verbal report in biofeedback holds that response awareness is unnecessary for learned control of visceral responding. However, more recent evidence has questioned this view. This article reports two experiments that analyzed verbal reports with the methods of recent studies while examining procedural differences between early and recent research. Experiment 1 assessed the effects of bidirectional versus unidirectional training on heart rate control and self‐report. Experiment 2 examined heart rate control and self‐report in two task environments that differed with regard to whether somatomotor action was afforded or allowed. No instances of response learning without response awareness were observed in either experiment, even when task environments approximating those of the early biofeedback studies were used. The results support viewpoints of biofeedback that assign a role to response awareness in the development of instructed control.
Brown and Eccles' Depiction of Vagal Effects: An Old and Widely Used Method Reexamined
Authors: Velden Manfred , Karemaker John M. , Wolk Christoph , Schneider Roland
Published: February 2007

It can be shown that the procedure for representing the effect of the vagal innervation of the heart introduced by Brown and Eccles in 1934 distorts the actual course of the inhibitory effect. A corrected procedure is proposed. It is stressed that cycle phase specificity of the stimulation can be studied only by drawing different curves representing the course of the vagal effect for different times of stimulation within the cardiac cycle.
Influences of Potential for Hostility, Type A Behavior, and Parental History of Hypertension on Adolescents’ Cardiovascular Responses During Stress
Authors: McCann Barbara S. , Matthews Karen A.
Published: February 2007

We investigated the influences of Type A behavior, potential for hostility, and parental history of diagnosed hypertension on adolescents’ cardiovascular responses to three behavioral stressors. The participants were 72 male and 99 female adolescents enrolled in grades 6 to 12. Results showed that adolescents with a hypertensive parent had larger diastolic blood pressure responses during all three stressors than did adolescents without hypertensive parents; this effect was particularly pronounced among the Type As. Adolescents rated as high on potential for hostility had elevated systolic and diastolic blood pressure responses, particularly during isometric exercise. Results regarding parental history of hypertension and Type A replicate previous studies in adolescents. Results regarding potential for hostility showed for the first time that early signs of hostility are related to psychophysiological responses thought to be pathophysiological mechanisms in the etiology of cardiovascular diseases.
Effects of Foveal Task Load on Visual‐Spatial Attention: Event‐Related Brain Potentials and Performance
Authors: Kramer Arthur F. , Sirevaag Erik J. , Hughes Paul R.
Published: February 2007

The effects of foveal task difficulty on the processing of events in the visual periphery were investigated through an analysis of event‐related brain potentials and performance measures. Subjects performed a foveally presented continuous monitoring task both separately and together with an arrow discrimination task that was presented at three different retinal eccentricities. The subjects detected occasional failures in the monitoring task while also responding to designated targets in the left and right visual fields. The analysis of the event‐related brain potentials elicited by discrete events in the arrow discrimination task indicated that the amplitude of the N190 and P300 components decreased with both the introduction of the foveal task and an increase in its difficulty. The N160 component was sensitive to the distribution of attention within a task but was uninfluenced by dual task demands. These findings suggest that the N160 reflects the distribution of attention to different spatial locations within a task while the N190 may index the distribution of general purpose perceptual resources. P300 appears to index the allocation of perceptual/central processing resources. The implications of the results for models of resource allocation and attentional gradients are discussed.
Electrodermal Lability and Dichotic Listening
Authors: O'Gorman J. G. , Lloyd Jacqueline E. M.
Published: February 2007

Subjects identified as electrodermal labiles and stabiles on the basis of frequency of nonspecific skin conductance responses during a resting period were presented with a series of auditory stimuli followed by dichotic presentation of different sets of words to each ear with the requirement to report as many words as possible irrespective of ear. Labiles performed better than stabiles on the dichotic listening task and were found to habituate skin conductance response more slowly to both tones and dichotic stimuli, and to show higher skin conductance level during both stimulus series and higher heart rate level during the dichotic series. There were no significant differences between the groups on a measure of EEG alpha activity during either series. The data were consistent with an arousal rather than an attentional interpretation of the labile‐stabile difference.
ERP Components in Picture Matching in Children and Adults
Authors: Friedman David , Sutton Samuel , Putnam Lois , Brown Charles , Erlenmeyer‐Kimling L.
Published: February 2007

Event‐related potentials (ERPs) were recorded from 22 young children (aged 6–8) and 25 adults (aged 20–38) in a modification, using pictorial stimuli, of Posner's (1978) letter‐matching paradigm. Subjects were required to decide whether two line drawings, presented sequentially, were the same or different on the basis of whether they were physically identical, shared the same name, or were in the same category. Subjects always made a choice “same’ or “different” delayed response whose meaning depended on the operative instruction condition in that block of trials.

The ERPs elicited by S1 and S2 with this paradigm from both age groups were of complex morphology, with P300 to both S1 and S2, the E‐wave preceding S2, and N400 possibly homologous for children and adults. P300, N400, and E‐wave probably had similar functional roles for children and adults as attested by the lack of significant interactions between age groups and the cognitive variables manipulated in the experiment. However, group differences in scalp distribution for one of these components suggest that although they may be generically similar across groups, they are probably not identical with respect to brain generators. In addition, there were group differences in timing of P300 in the two age groups. Overall, the ERP findings suggest that the cognitive processing of children and adults in the same task is different, although the behavioral data lend only partial support for these conclusions.
Early and Late Selection in Young and Old Adults: An Event‐Related Potential Study
Authors: de Jong Huib Looren , Kok Albert , van Rooy John C.G.M.
Published: February 2007

The present experiment investigated differences in processing between young and old adults in a combined visual selection‐memory search paradigm. No evidence was found for age‐related differences in early visual selective attention. The elderly achieved relatively fast reaction times in the memory search task at the cost of a high error percentage. From these findings, and from the morphology of the event‐related potential, it was concluded that old subjects perform controlled memory search more superficially than young subjects, In both old and young subjects high memory load was associated with decreased positivity in the P3 and Slow Wave area. This is interpreted in terms of Okita et al.'s(1985) concept of search negativity. N2 amplitude was found to be larger to non‐target trials for both attended and unattended inputs. The latter result is discussed in relation to theories about N2 as an indicator of automatic mismatch detection.
Difficulty and Instrumentality of Imminent Behavior as Determinants of Cardiovascular Response and Self‐Reported Energy
Authors: Wright Rex A. , Gregorich Steve
Published: February 2007

College‐aged male subjects were presented with an easy or moderately difficult memorization task and were told that they could earn either a very low or a very high chance of obtaining a modest prize if they did well. Cardiovascular (heart rate, systolic blood pressure, diastolic blood pressure) and subjective measures were taken during an interval immediately preceding the task performance period. Results indicated greater systolic blood pressure and self‐perceived energy in the moderately difficult condition than in the easy condition only when the probability of attaining the prize (if subjects did well) was high. When the probability of goal attainment (given success) was low, systolic responses and self‐reported energy levels were minimal in both task conditions. Predictions regarding the impact of energy levels upon goal attractiveness ratings were not supported, possibly for methodological reasons.
Variations in Period‐Analysed EEG Asymmetry in REM and NREM Sleep
Authors: Armitage Roseanne , Hoffmann Robert , Loewy Derek , Moffitt Alan
Published: February 2007

Monopolar EEG was recorded from lateral frontal and parietal sites with linked ear reference during sleep in 24 adults. Electrode placement followed the 10–20 International system. EEG was quantified using digital period analyses. The absolute difference in interhemispheric EEG parameters was compared for Stage 2, REM, and a slow wave sleep measure. The absolute difference measures reflect the degree of symmetry or asymmetry, regardless of the hemisphere of origin. Theta and delta activity in slow wave sleep was more asymmetrical than in either Stage 2 or REM. REM sleep was associated with the smallest asymmetries. These results do not support a right hemisphere REM, left hemisphere NREM relationship. Rather they suggest that REM sleep is associated with relative hemispheric symmetry whereas asymmetries are most prominent in slow wave sleep. Stage 2 sleep was significantly less asymmetrical than slow wave on a number of theta and delta measures. The significant differences between slow wave and Stage 2 sleep may denote functional differences within NREM sleep stages.
Effects of Motivation and Verbal Response Type on Psychophysiological Detection of Information
Authors: Elaad Eitan , Ben‐Shakhar Gershon
Published: February 2007

Two independent experiments were designed to investigate the effects of motivation to deceive and the type of verbal response on psychophysiological detection using the Guilty Knowledge Technique. The first was a field experiment in which 72 subjects were randomly assigned to 8 experimental conditions. These conditions were created by a 2 × 4 factorial design (two motivational states crossed with four verbal response modes‐affirming, denying, repeating, or no verbal response to questions about personal information). The second experiment was a laboratory experiment in which 160 students were assigned to the same 8 conditions. Results of both experiments indicated that highly motivated subjects were detected better than less motivated subjects. The act of lying was associated with enhanced differential responsivity, but no effects were obtained for verbal response versus no response or for variable versus standard verbal response. Differential responsivity tended to decline when questions were repeated. The first experiment revealed a clear advantage of electrodermal measures over respiration and cardiovascular measures. The results were discussed in relation to previous findings, a new theoretical formulation, and practical implications.
Prepulse Rise Time and Startle Reflex Modification: Different Effects for Discrete and Continuous Prepulses
Authors: Blumenthal Terry D. , Levey Bard J.
Published: February 2007

The rise time of an auditory prepulse was varied to determine whether the onset transient of the prepulse is of primary importance in the modification of the acoustic startle reflex. In Experiment 1, 20‐ms long discrete prepulses were presented at a lead time of 150 ms, and prepulse rise time was varied from 0.1 to 20 ms. Although all prepulses resulted in decreased response amplitude (inhibition of startle), varying rise time from 0.1 to 20 ms had no effect on reflex modification. These results suggest that the startle response is not sensitive to prepulse rise time changes in the range used here. In Experiment 2, continuous prepulses (in which lead time equals duration) were presented. Several of these prepulses had a lead time of 150 ms and rise times ranging from 0.1 to 150 ms, whereas others had a rise time of 0.1 ms and lead times of 50 to 150 ms. The results showed that only the fast‐rising, 50‐ms lead time prepulse decreased response amplitude, with the other prepulses having no effect on amplitude, relative to control responding. Rise time changes generally had no effect on responding, but responses were larger at longer lead times than at shorter lead times. Response probability was inhibited by fast‐rising prepulses at lead times of 50 to 130 ms. Together with the results of Experiment 1, these findings suggest that startle reflex inhibition is determined by the onset of a prepulse, and that this inhibition is not sensitive to small changes in prepulse rise time. Also, startle reflex facilitation is determined by the steady‐state portion of the prepulse, and this effect is sensitive to prepulse duration. The inhibitory and facilitatory effects combine to determine the amount and direction of reflex modification, and these effects have different time courses, suggesting different mechanisms. It is suggested that reflex modification is due to the activation of a transient system for startle inhibition and a sustained system for startle facilitation.
Aerobic Fitness, Physical Activity, and Psychophysiological Reactions to Mental Tasks
Authors: Steptoe Andrew , Moses Jennifer , Mathews Andrew , Edwards Sara
Published: February 2007

The association between aerobic fitness, exercise, and psychophysiological reactivity was assessed in cross‐sectional and prospective analyses. Seventy‐five healthy but sedentary adults carried out a sub‐maximal exercise test and easy and difficult problem solving tasks. Blood pressure, heart rate, skin conductance level, respiration rate, tidal volume, and oxygen consumption were monitored and additional heart rate was also computed. Differences between relatively fit and unfit individuals were found in respiration rate during tasks and in skin conductance level during post‐task recovery periods, with a tendency toward diminished heart rate reactivity in fitter people. Subjects were subsequently allocated to four conditions: high intensity aerobic training, moderate intensity aerobic training, an undemanding strength and flexibility program (designed as an attention‐placebo condition), and waiting list control. Training programs were conducted over a 10‐week period, and were followed by a second laboratory session. Appropriate changes in aerobic performance over the training period were observed in the 12‐min run/walk test. There were no important modifications in psychophysiological stress reactions associated with the different experimental conditions. These results are discussed in relation to the literature concerning the effects of fitness and physical activity on physiological response patterns.
Do Instructions Modify Effects of Beta‐adrenoceptor Blockade on Anxiety?
Authors: Fredrikson Mats , Klein. Kerstin , ÖHman Arne
Published: February 2007

To study the interaction between physiological and cognitive factors in anxiety, 44 subjects with public speaking anxiety were allocated to four different groups. Two groups received either beta‐adrenoceptor blockade (100 mg of atenolol) or placebo orthogonally crossed with an instruction that heart rate would decrease or an instruction that did not mention cardiovascular effects. During the delivery of a speech, measures of heart rate, systolic and diastolic blood pressures, and self‐reported anxiety were obtained. All variables increased during an anticipation period before speech, and heart rate, systolic blood pressure, and self‐reported anxiety increased further during speech. Regardless of instructions, atenolol decreased heart rate and systolic blood pressure during both anticipation and speech, whereas no differences were found in self‐reported anxiety. This lack of a relationship was seen in spite of the correctly perceived heart rate reduction in the atenolol‐treated group receiving an instruction that heart rate would decrease. Cardiac aware subjects, according to the Autonomic Perception Questionnaire, showed higher levels of heart rate and self‐reported anxiety at rest than did cardiac unaware subjects. During speech, even though heart rate was similar in atenolol treated groups, self‐reported anxiety was higher in cardiac aware than in cardiac unaware subjects. The lack of a relationship between heart rate and self‐reported anxiety is discussed in terms of primary and secondary emotions. It is suggested that the perception of external rather than internal cues determines situationally elicited anxiety.
Asymmetrical Brain Electrical Activity Discriminates Between Psychometrically‐Matched Verbal and Spatial Cognitive Tasks
Authors: Davidson Richard J. , Chapman Jean P. , Chapman Loren J. , Henriques Jeffrey B.
Published: February 2007

This study compared the asymmetry of different features of brain electrical activity during the performance of a verbal task (word finding) and a spatial task (dot localization) that had been carefully matched on psychometric properties and accompanying motor activity. Nineteen right‐handed subjects were tested. EEG was recorded from F3, F4, C3, C4, P3, and P4, referred to both Cz and computer‐derived averaged‐ears references, and Fourier transformed. Power in the delta, theta, alpha, and beta bands was computed. There were significant Task X Hemisphere effects in all bands for Cz‐referenced data and for the alpha and beta bands for ears‐referenced data. The effects were always either greater power suppression in the hemisphere putatively most engaged in task processing or greater power in the opposite hemisphere. Correlations between EEG and task performance indicated that Cz‐referenced parietal alpha asymmetry accounted for the most variance in verbal task performance. Power within individual hemispheres or across hemispheres was unrelated to task performance. The findings indicate robust differences in asymmetrical brain physiology that are produced by well‐matched verbal and spatial cognitive tasks.
Photoresistive Measurement of the Pavlovian Conditioned Eyelid Response in Human Subjects
Authors: Durkin Martin , Prescott Louisa , Jonet C. Jean , Frank Elaine , Niggel Michael , Powell Donald A.
Published: February 2007

An inexpensive technique is described for measuring eyelid closure during classical (Pavlovian) conditioning experiments. This technique employs a Coulbourn Instruments Co. densitometric device that focuses a beam of infrared light on the cornea. Reflection of the light is interrupted by the eyelids when they are closed, which is sensed by an infrared detector. The latter causes a voltage change to occur, which can then be measured in a variety of ways. Details of both the hardware required and software developed for this purpose are described.
Disruption and Recovery of the Orienting Response Following Shock or Context Change in Preweanling Rats
Authors: Saiers Jane A. , Richardson Rick , Campbell Byron A.
Published: February 2007

Previous research has shown that placement of preweanling rats in an unfamiliar environment inhibits both heart rate and behavioral orienting responses to an auditory stimulus, and that the orienting response gradually reappears during the following 15 min. Four experiments designed to evaluate two potential explanations of this effect were conducted. If the arousal induced by an unfamiliar environment disrupts sensory information processing, so should the arousal induced by mild electric shock. In two experiments, the orienting response was inhibited in proportion to number of shocks received and rate of recovery was comparable to that observed in the unfamiliar environment. New environments also contain many unfamiliar stimuli which may overload the rats’ limited information processing capacity. In two experiments a change in environmental stimulation was shown to inhibit the orienting response. Recovery of the orienting response followed the same time course as that seen following shock or placement in an unfamiliar environment. Although the results of this study clearly demonstrate environmental inhibition of the orienting response, they provide little support for either the “arousal” or the “information overload” hypotheses of orienting response inhibition. The implications of these data for current theoretical conceptualizations of the orienting response are discussed.
Existing and Training Induced Differences in Aerobic Fitness: Their Relationship to Physiological Response Patterns During Different Types of Stress
Authors: DE Geus Eco J.C. , van Doornen Lorenz J.P. , de Visser Dianne C. , Orlebeke Jacob F.
Published: February 2007

Aerobic fitness has been associated with various desirable psychological and physiological characteristies. Recently, attenuation of physiological reactivity during stressful situations was added to this list, although comparison of the stress responses of sportsmen and sedentary subjects has yielded equivocal results. The present study examined cardiovascular patterns rather than single variables, and tried to clarify these matters. Tasks were used that were known to increase blood pressure through different combinations of changes in cardiac output and vascular resistance. Autonomic nervous system dynamics underlying these response patterns were studied using preejection period as an index of β‐adrenergic activity, and respiratory sinus arrhythmia as an index of vagal activity. Pre‐existing differences in aerobic fitness in a sample of sedentary subjects were related to their responses during the stressful tasks and the recovery periods afterwards. This approach prevented confounding of the relationship between fitness and stress‐reactivity with the psychological effects of regular exercise. Furthermore, it excluded the bias in psychological makeup that is introduced when subjects spontaneously engaged in sports are compared to non‐exercising persons. To rule out a third (hereditary?) factor underlying both stress‐reactivity and fitness, physiological responses before and after a seven‐week training program were compared to those of subjects in a waiting list control group. Substantial individual differences in aerobic fitness were found in spite of the fact that all subjects reported low levels of habitual activity. During two active coping tasks, diastolic blood pressure reactivity and vagal withdrawal were negatively related to these pre‐existing differences in fitness. No such relation was seen during a cold pressor test or during recovery from the tasks. Neither β‐adrenergic cardiac reactivity nor heart rate responses were related to fitness, but the absolute heart rate during the tasks was lower in the more fit subjects. Seven weeks of training were not effective in changing either reactivity or recovery of any of the variables. The discrepancy between cross‐sectional and longitudinal results in the present study suggests that training of longer duration is necessary to induce the psychological or physiological changes underlying reduced reactivity. The latter may include changes in cardiac vagal/sympathetic balance or in adrenoceptor sensitivity. Alternatively, both psychological and physiological determinants of stress‐reactivity may be related to aerobic fitness at a dispositional level.
Electrodermal Responsivity in Young Hypotensive and Hypertensive Men
Authors: Fredrikson Mats , Edman Gunnar , Levander Sten E. , Schalling Daisy , Svensson Jan , Tuomisto Martti
Published: February 2007

Electrodermal responses were recorded during the presentation of 16 moderately intense (1000 Hz, 90dB) tones in three groups of young men: borderline hypertensives (138/79 mmHg), normotensives (112/65 mmHg), and hypotensives (104/63 mmHg). Electrodermal response habituation was measured as a decline in response over trials, number of trials to a response criterion of three successive nonresponses, and number of inversions of response amplitude (larger responses following smaller responses) in the stimulus sequence. Habituation was fastest in hypotensives. Nonspecific electrodermal responses at rest and during tone presentations were most frequent in borderline hypertensives, least frequent in the hypotensive group, with the normotensive group falling in between. There were no significant differences in electrodermal level. The rapid habituation rate in hypotensives is discussed in terms of cursory information processing associated with impulsive behaviour. The higher nonspecific electrodermal activity in borderline hypertensives is interpreted to indicate increased sympathetic nervous system activity.
Event‐Related Potentials in a Visual Discrimination Task: Negative Waves Related to Detection and Attention
Authors: Czigler Istvan , Csibra Gergely
Published: February 2007

Event‐related potential effects of deviant stimuli were investigated in a visual discrimination task. The stimuli (two angles within a frame) were either frequent (Standard) or one of two types of infrequent deviant (Deviant 1 or Deviant 2) stimuli. In comparison to the Standard stimuli, for Deviant 1 the two angles differed in their orientation, whereas for Deviant 2 the angles were identical but the frame was thicker. In Condition 1 the subjects counted the number of Deviant 1 stimuli. Of the 13 subjects, 12 did not detect the fact that some of the frames were thicker in this condition (i.e., for the Deviant 2 stimuli in Condition 2). The task in Condition 2 was the same (i.e., the target was Deviant 1), but the subjects were instructed about the thicker frame of Deviant 2 stimuli. In Condition 3, Deviant 2 stimuli became the targets. In comparison to the Standard, Deviant 1 elicited two posterior negative waves in the 120–180 and 240–300 ms latency ranges respectively. In addition, when Deviant 1 was the target stimulus (Conditions 1 and 2), this stimulus elicited the N2 and the P300 as well. In contrast, the irrelevant Deviant 2 elicited no such waves. In the target position (Condition 3), Deviant 2 elicited the second posterior negativity, the N2, and the late positivity. The earlier negativity is considered to be a correlate of processes connected to the automatic detection of the deviant features, whereas the later negativity is considered to be related to attentive processes, i.e., this wave is considered to be a member of the family of processing negativities.
The Roles of Deception, Intention to Deceive, and Motivation to Avoid Detection in the Psychophysiological Detection of Guilty Knowledge
Authors: Furedy John J. , Ben‐Shakhar Gershon
Published: February 2007

The present study focused on electrodermal differentiation between relevant and neutral items in the Guilty Knowledge paradigm. Three factors were varied in a between‐subjects design. The role of deception was examined by varying the type of verbal answer to the questions (“yes,”“no,” and remaining silent). The intention to deceive factor was examined by contrasting subjects told to delay their answer (“yes” or “no”) with those told to produce their answer immediately. Finally, motivation to avoid detection was manipulated by having half the subjects monetarily rewarded for an important (ego relevant) detection task (high motivation), whereas the remaining subjects were neither rewarded nor told that the task was important. The results indicated that a deceptive answer (“no”) to the relevant question was associated with an increased differential skin conductance responsivity, but better than chance detection rates were obtained with truthful (“yes”) and silent conditions. Equal and significant detection rates were observed when the responses were computed immediately following question presentation, whether the subjects had answered immediately or had delayed their answers. In contrast, differential electrodermal responsivity to the delayed answers was markedly attenuated. The motivation factor had no main or interactive effects on differential responsivity. The present results, together with those obtained in previous studies, suggest that whereas deception is neither a necessary nor a sufficient condition for psychophysiological detection, it may facilitate detection. Possible mechanisms through which such a facilitation could occur were considered.
Effects of Feedback on the Control of Skin Temperature Using the Tension‐Relaxation Experiment
Authors: Okouchi Hiroto
Published: February 2007

The effects of feedback on the control of peripheral skin temperature were examined using a tension‐relaxation experiment. Sixteen male undergraduates were assigned to feedback or no‐feedback groups and asked to increase the temperature of the right index finger immediately after decreasing with (in the feedback group) or without (in the no‐feedback group) feedback during 10 training sessions. A no‐feedback transfer session (post‐test) followed these sessions. During the training sessions, skin temperature corresponded to instructions in the feedback group, whereas it did not in the no‐feedback group. Feedback control did not transfer to the no‐feedback condition. These results were discussed in terms of the ceiling‐effect hypothesis in the baseline‐relaxation type experiment and of the subjects' cognitive events, including strategies.
Fear‐Potentiated Startle in Humans: Effects of Anticipatory Anxiety on the Acoustic Blink Reflex
Authors: Grillon Christian , AMELI Rezvan , Woods Scott W. , Merikangas Kathleen , Davis Michael
Published: February 2007

The effects of fear/anticipatory anxiety on the acoustic startle reflex were investigated in humans using a paradigm involving anticipation of electric shocks. The eyeblink component of the startle reflex, elicited by an abrupt auditory stimulus, was measured in 9 normal volunteers during either the anticipation of electric shocks (anticipatory anxiety) or periods in which no shocks were anticipated (safe period). The eyeblink was consistently higher in amplitude, and shorter in latency, during periods when the subjects anticipated shocks, compared to the safe periods. This effect could not be attributed solely to a reduction in habituation and was statistically significant before the subjects actually received any shock (a single 30 mA stimulation on the median nerve). These results indicate that anticipatory anxiety can be measured objectively in humans using the fear‐potentiated startle reflex in a paradigm not actually requiring any shock. Because a great deal is known about the neuroanatomical and pharmacological mechanisms of fear‐potentiated startle in laboratory animals, this test procedure may be especially useful in humans to investigate the neurobiological substrates of anxiety disorders and their pharmacological treatments.
Complexities Related to Cognitive Slow Wave Experiments: A Reply to Rösler and Heil
Authors: Ruchkin Daniel S. , Johnson Ray
Published: February 2007

Rösler and Heil (1991) were unable to replicate one of the results of our previous study of slow wave activity and mental arithmetic (Ruchkin, Johnson, Mahaffey, & Sutton, 1988). Thorough examination of the error rates indicates that the greater complexity of their response selection procedure caused crucial differences between how the task was performed in the two studies. Thus Rösler and Heil's study emphasizes the need to avoid using a response that is so complex that it produces a superfluous task that obscures the results.
A Negative Slow Wave Related to Conceptual Load Which Vanishes if the Amount of Load is Increased? A Reply to Ruchkin and Johnson
Authors: Rösler Frank , Heil Martin
Published: February 2007

Ruchkin and Johnson (1991) claim that the mode of responding used by Rösler & Heil (1991) may have camouflaged effects of a negative slow wave that Ruckin et al. (1988) had found to be related to the difficulty of mental calculation problems. This criticism is addressed by three arguments which support the interpretation of Rösler and Heil (1991). According to this view, the negative slow wave in question is more likely related to unspecific processing factors, such as effort and event expectation, than to specific processing demands such as these induced by mental arithmetic.
Effects of Eating on Vection‐Induced Motion Sickness, Cardiac Vagal Tone, and Gastric Myoelectric Activity
Authors: Uijtdehaage Sebastian H.J. , Stern Robert M. , Koch Kenneth L.
Published: February 2007

This study investigated the effect of food ingestion on motion sickness severity and its physiological mechanisms. Forty‐six fasted subjects were assigned either to a meal group or to a no‐meal group. Electrogastrographic (EGG) indices (normal 3 cpm activity and abnormal 4‐9 cpm tachyarrhythmia) and respiratory sinus arrhythmia (RSA) were measured before and after a meal and during a subsequent exposure to a rotating drum in which illusory self‐motion was induced. The results indicated that food intake enhanced cardiac parasympathetic tone (RSA) and increased gastric 3 cpm activity. Postprandial effects on motion sickness severity remain equivocal due to group differences in RSA baseline levels. During drum rotation, dysrhythmic activity of the stomach (tachyarrhythmia) and vagal withdrawal were observed. Furthermore, high levels of vagal tone prior to drum rotation predicted a low incidence of motion sickness symptoms, and were associated positively with gastric 3 cpm activity and negatively with tachyarrhythmia. These data suggest that enhanced levels of parasympathetic activity can alleviate motion sickness symptoms by suppressing, in part, its dysrhythmic gastric underpinnings.