bluuebunny/crossref_metadata_2025_split huggingface dataset:
Memory Retrieval in Noise and Psychophysiological Response in the Young and Old
Authors: Jennings J. Richard , Nebes Robert , Brock Kay 
Published: February 2007

ABSTRACTBoth noise and aging induce changes in memory performance that have been attributed to physiological overarousal. The aim of the current experiment was to examine variation in performance due to noise and aging and to determine if this variation was related to variation in general arousal or, alternatively, to changes in processes specifically required by memory retrieval. The cardiovascular responses of young and old men (n=30) were compared during a memory retrieval task performed in acoustic noise. Noise (90dBA) and old age independently increased the number of associatively cued recall errors relative to orthographically cued recall errors. Despite the change in errors, changes in general arousal were not observed in response to noise in either young or old volunteers. The task sequence induced consistent cardiac and vascular responses which were related to attention and rehearsal requirements, and also to performance. This suggests that task processing induces supportive physiological changes rather than that physiological change (arousal) constrains performance. Noise and age may alter physiological change independently by altering task processing and requirements for physiological support.
Electrodermal Lability and Visual Information Processing
Authors: Wilson Keith G. , Graham Randall S. 
Published: February 2007

ABSTRACTIndividual differences in electrodermal lability have been related to performance in vigilance and reaction time tasks. The goal of the present study was to employ an “additive factors’ approach to identify the stages of information processing that might underlie these effects. Nineteen labile and 17 stabile subjects performed a choice reaction time task in which a visual imperative stimulus was presented under two conditions of intensity (presumed to affect the speed of pre‐processing operations) X three conditions of degradation (which influences later encoding processes related to feature extraction). Measures of both reaction time and movement time were obtained. The major findings were: (a) labile subjects had faster reaction times than stabiles, and (b) lability interacted significantly with stimulus degradation. Labiles also tended (p<.10) to have faster movement times. This pattern indicates that labiles and stabiles differ in the performance of later encoding operations, and possibly in the speed of motor processes as well. However, they do not appear to differ in the early pre‐processing of the simple physical attributes of a stimulus.
Sleep on the Night Shift: 24‐Hour EEG Monitoring of Spontaneous Sleep/Wake Behavior
Authors: Torsvall Lars , Akerstedt Torbjöurn , Gillander Katja , Knutsson Anders 
Published: February 2007

ABSTRACTThe present study sought to objectively describe the spontaneous sleep/wakefulness pattern of shift workers during a 24‐hour period. Portable Medilog tape‐recorders were used for ambulatory EEG monitoring of 25 male papermill workders (25–55 years) during days with night and afternoon work. The rusults showed that sleep after night work was two hours shorter than after afternoon worl. The sleep reduction affected mainly Stage 2 and REM sleep while slow wave sleep was unchanged. In connection with night work 28% of the workders took a nap in the afternoon. These naps contained a large proportion of slow wave sleep and were, apparently, caused by the sleep deficit after the short main sleep period. The EEG recordings also revealed that 20% of the participants had sleep episodes during night work. These naps were as long as the afternoon naps, were experienced as “dozing off” ragher than naps. Occurred at the time of the though of the circadian wakefulness rhythm, and were concomitant with extreme subjective sleepiness and low rated work load. It was concluded that not only the sleep of shift workders was disturbed, but also the wakefulness‐ to the extent that sleepiness during night work sometimes reached a level where reasonable wakefulness could not be maintained. The latter observation is probably of special importance in work situations demanding a great responsiility of human lives or for great economic values.
Self‐Report During Feedback Regulation of Slow Cortical Potentials
Authors: Roberts Larry E. , Birbaumer Niels , Rockstroh Brigitte , Lutzenberger Werner , Elbert Thomas 
Published: February 2007

ABSTRACTSubjects received exteroceptive feedback for bidirectional changes in slow cortical potentials or alpha power measured from the vertex. The slow potential group succeeded in shifting slow potentials toward negativity and positivity on feedback and transfer trials requiring these changes, after two sessions of training. Differentiation of negativity and positivity was accompanied by verbal reports of somatomotor activation that occurred on trials on which negative slow potentials were required (p < .01). Vertical and lateral eye movements, chin and frontalis electromyogram, and heart rate did not differentiate between negativity and positivity trials in the slow potential group. However, heart rate acceleration correlated between‐subjects with slow potential negativity during feedback. Although the alpha power group did not succeed at controlling changes in alpha, evidence of a training effect appeared in verbal reports of emotional arousal (p< .05) and focused vision (p< .08) on alpha suppression trials in this group. We discuss the findings from the viewpoint that biofeedback tasks involving electrocortical responses are problems in the organization of action that subjects seek to solve.
Development and Stability in Visual Sustained Attention in 14, 20, and 26 Week Old Infants
Authors: Richards John E. 
Published: February 2007

ABSTRACTInfants were studied at 14, 20, and 26 weeks of age in a longitudinal design. They were presented with varying and complex patterns on a TV screen. Two‐thirds of the presentations were accompanied by a stimulus in the periphery delayed in time from the onset of fixation on the central stimulus. As in previous research, the infants were not as easily distracted by the interrupting stimulus when the presentation occurred at the point of maximal heart rate deceleration as when the presentation occurred at the end of the heart rate response. Infants with large amounts of respiratory sinus arrhythmia (i.e., heart rate variability) in a baseline recording were less distractible during the deceleration‐defined trials than were infants with low amounts of respiratory sinus arrhythmia. Intra‐individual patterns of development in respiratory sinus arrhythmia over the testing ages were closely paralleled by patterns of heart rate responding during sustained attention. Individual differences in baseline levels of heart rate and respiratory sinus arrhythmia were more stable than individual differences in sustained attention. The stability of attention responses over age may be mediated by the stability of the physiological system (e.g., heart rate, respiratory sinus arrhythmia, etc.), and by the within‐age relation of attention to heart rate variability.
Modulation of Event‐Related Potentials by Word Repetition: The Effects of Inter‐Item Lag
Authors: Nagy Margaret E. , Rugg Michael D. 
Published: February 2007

ABSTRACTThe modulation of event‐related potentials by word repetition was investigated in two experiments. In both experiments, subjects responded to occasional nonwords interspersed among a series of words. A proportion of the words were repetitions of previously presented items. Words were repeated after 0 or 6 intervening items in Experiment 1 and after 6 or 19 items in Experiment 2.Event‐related potentials to repeated words were characterised by a sustained, widespread positive‐going shift with an onset of approximately 300 ms. This effect did not vary significantly as a function of lag in either experiment. When words were repeated immediately, this repetition‐evoked positive shift was preceded by a transient negative deflection (onset ca. 200 ms) which was absent in event‐related potentials to words repeated at longer lags.These results suggest that the modulation of event‐related potentials by word repetition is influenced by at least two processes. One of these processes acts relatively early during the processing of a repeated word, but subsides rapidly as inter‐item lag between first and second presentations increases. The second process occurs later in time, but is considerably more robust over variations in inter‐item lag.
Bootstrapping: Applications to Psychophysiology
Authors: Wasserman Stanley , Bockenholt Ulf 
Published: February 2007

ABSTRACTThis paper presents the statistical technique known as thebootstrapto the general audience of psychophysiologists. The bootstrap, introduced by Efron (1979), allows data analysts to study the distribution of sample statistics that might otherwise be too complicated to consider. The technique, which requires simple calculations, involves drawing repeated samples (with replacement) from the empirical–or the actual–data distribution and then building a distribution for a statistic by calculating a value of the statistic for each sample. The bootstrap can be used to obtain confidence intervals, standard errors, and even higher moments for the statistic. It is similar to the well‐known jackknife of Quenouille and Tukey. After discussing the history and theory of both the bootstrap and the jackknife, we illustrate the use of the bootstrap in the statistical analysis of correlation coefficients and the general linear model.
Cognitive Determinants of the Postimperative Negative Variation
Authors: Kathmann Norbert , Jonitz Lothar , Engel Rolf R. 
Published: February 2007

ABSTRACTThis study examined cognitive determinants of the postimperative negative variation (PINV). a slow brain potential observable after the onset of an imperative stimulus in a forewarned reaction time task. Controllability of the aversive imperative stimulus by a motor reaction and predictability of the contingency were varied in a factorial design. The exogenous portion of the slow negative wave was assessed in a passive listening condition using tones of the same quality as the imperative stimuli. but presented without forewarning. Results show that PINV not only occurs when control is absent but also during unpredictably gained control. Similarly, unpredictable lack of control yields a more negative potential than continual helplessness. Negativity elicited by the aversive tone alone was not significantly different from PINV during predictable lack of control. The order of conditions, which was manipulated between groups, did not affect amplitudes. It was concluded that contingency change is a crucial cognitive determinant of the PINV, whereas the effect of lack of control is difficult to differentiate from the sensory influence of the acoustic stimulation.
Intergroup and Intrasubject Principal Component Analysis of Event‐Related Potentials
Authors: Guthrie Donald 
Published: February 2007

ABSTRACTThe purpose of this paper is to show that the familiar principal component analysis (PCA) of event‐related potentials is identical to an easily formulated least squares method. This correspondence permits interpretation of several criticisms of PCA and clearer presentation of its strengths and shortcomings. Because data analysis based on PCA compares amplitudes of empirically derived components, it is necessary that the shape of the components be similar under the experimental conditions. We present and illustrate a statistical method for comparison of principal components across groups and between conditions within subjects.
The Relationship Between Skin Conductance Orienting the Allocation of Processing Resources
Authors: Filion Diane L. , Dawson Michael E. , Schell Anne M. , Hazlett Erin A. 
Published: February 2007

ABSTRACTInformation processing models of autonomic orienting suggest that the elicitation of an orienting response is associated with either the call for, or the actual allocation of, limited attentional processing resources. However, Dawson, Filion, and Schell (1989) reported a directional dissociation between elicitation of the skin conductance orienting response and resource allocation, as indexed by reaction time slowing on a secondary task. Although larger skin conductance responses were elicited by a task‐relevant stimulus than by a task‐irrelevant stimulus, reaction time showed the opposite pattern (i.e., greater slowing to secondary task probes presented shortly following the onset of the task‐irrelevant stimulus). In the present report, we describe three experiments which examine the generality of this dissociation effect and test specific hypotheses regarding its nature. Results of the first two experiments revealed that the dissociation effect is observed reliably when the taskrelevant and task‐irrelevant stimuli consist of left ear and right ear tones or high and low pitched binaural tones, across a range of secondary task probe presentation times. However, the third experiment demonstrated that when task‐relevant and task‐irrelevant stimuli are presented to different sensory modalities (auditory and visual), orienting and resource allocation are both greater during the task‐relevant than the task‐irrelevant stimuli, thus eliminating the dissociation effect. These results support the hypothesis that the dissociation effect is due to a switch of attention initiated because of the physical similarity of the task‐relevant and task‐irrelevant stimuli, and suggest that there is a fundamentally positive relationship between skin conductance orienting and resource allocation under selective attention conditions.
Probing the Time‐Course of the Auditory Oddball P3 With Secondary Reaction Time
Authors: Woodward Steven H. , Brown Warren S. , Marsh James T. , Dawson Michael E. 
Published: February 2007

ABSTRACTAn elementary neural model of the P3 is proposed in which the P3 is held to manifest a brief, widely‐distributed, inhibitory event. A preliminary and indirect test of the model is described using secondary‐task methodology. Manual reaction times were measured to probe clicks delivered during the presumed time‐course of an auditory oddball P3. We observed that reaction times to probes presented after oddball stimuli were significantly slowed as compared to reaction times to probes presented after standards. The latency of maximum reaction time slowing corresponded generally to the latency of the P3. The latency of maximum reaction time slowing did not respond to a manipulation varying the latency of the P3. Thus, some of the obtained results were consistent with the P3‐inhibition hypothesis, whereas others were not. Secondary‐task methodology may provide a valuable new approach to understanding the late event‐related potentials.
Abnormal Processing of Affective Words by Psychopaths
Authors: Williamson Sherrie , Harpur Timothy J. , Hare Robert D. 
Published: February 2007

ABSTRACTWe tested the hypothesis that psychopathy is associated with abnormal processing of affective verbal material. Criminal psychopaths and nonpsychopaths, defined by the Psychopathy Checklist, performed a lexical decision task (“Is it a word or not”) while we recorded reaction time and eventrelated potentials in response to letter‐strings consisting of affective and neutral words and pronounceable nonwords. On the assumption that they do not make efficient use of affective information, our primary prediction was that psychopaths would show less behavioral and eventrelated potential differentiation between affective and neutral words than would nonpsychopaths. The results were in accordance with this prediction. The lexical decisions of nonpsychopaths were significantly faster, and relevant event‐related potential components were significantly larger, to affective words than to neutral words. In sharp contrast, psychopaths failed to show reaction lime facilitation or larger amplitude event‐related potentials to affective words. We suggest that psychopaths extract less information from affective words than do other individuals. Possible implications of these and related findings for understanding the behavior of psychopaths are discussed.
A Nonstationarity Test for the Spectral Analysis of Physiological Time Series with an Application to Respiratory Sinus Arrhythmia
Authors: Weber Edith J.M. , Molenaar Peter C.M. , van der Molen Maurits W. 
Published: February 2007

ABSTRACTThe spectral analysis of time series requires the signal to be at least weakly statonary; i.e., the mean, (co‐) variance, and spectrum of the time series should not vary from segment to segment. It is commonly assumed that psychophysiological time series are not stationary. This study introduces a nonstationarity test to the psychophysiological literature, which is derived from evolutionary spectral analysis. Basically, the test consists of a double window technique in both the time and frequency domains, leading to a two‐way analysis of variance for times and frequencies. In the current study, the nonstationarity test is applied to heart rate data obtained in a typical psychophysiological setting. Heart rate and respiration were measured in four age groups under four conditions—rest, paced breathing, vigilance, and reaction time. The results indicate that only few physiological time series were completely stationary. However, for every subject, and in every condition stationary strectches could be found that were long enough to apply spectral analysis. Spectral measures (power, coherence, and phase spectra) were then compared for stationary parts of the data and the total data. This comparison indicated that nonstationarity affects all spectral measures. Most importantly, Stationarity × Task Condition × Frequency Band interactions were observed for coherence and phase spectra, and there were significant interactions with age for each of the spectral indices. These findings suggest that nonstationarity may result in biased outcomes of significance tests of the effects of task manipulations on the spectral indices of cardiac time series. Thus, it was concluded that the stationarity test should be routinely applied in the spectral analysis of physiological time series. In addition, it was suggested that the nonstationarity test has an even wider range of application that might be of interest to the psychophysiologist.
Pictures as prepulse: Attention and emotion in startle modification
Authors: BRADLEY MARGARET M. , CUTHBERT BRUCE N. , LANG PETER J. 
Published: February 2007

AbstractThe effects of an emotional stimulus prepulse on probe startle response were examined here. Pleasant, neutral, and unpleasant pictures were viewed for 6 s, and an acoustic startle probe was presented either 300, 800, 1,300, or 3,800 ms after slide onset, or 300 or 3,800 ms after slide offset. Blink magnitude and onset latency demonstrated (a) an early (prepulse) inhibition effect in which reflexes elicited immediately after slide onset were smaller than reflexes elicited later in the viewing interval, and (b) affective modulation, in which unpleasant stimuli prompted larger reflexes than pleasant. Interactive effects of probe time and picture valence indicated attention/arousal effects early and pleasantness effects late in the picture interval. Effects of both attention and emotion can be simultaneously measured using this startle‐probe paradigm, encouraging its use in both basic and clinical contexts.
Cardiovascular activity during mental stress following vigorous exercise in sportsmen and inactive men
Authors: STEPTOE ANDREW , KEARSLEY NICOLA , WALTERS NICK 
Published: February 2007

AbstractThirty‐six competitive sportsmen and 36 inactive men participated in a two‐session experiment. Session 1 involved exercise to exhaustion so as to assess maximal oxygen consumption (V̇o2 max. In Session 2, both groups were randomized into three experimental conditions: 20 min of exercise at high intensity (70%V̇o2 max) or moderate intensity (50% V˙o2 max) or a light exercise control. Following 30 min of recovery, all subjects performed mental arithmetic and public speech tasks in a counterbalanced order. Cardiovascular, electrodermal, respiratory, and subjective variables were recorded. Sportsmen had higher V˙o2 max, lower body fat, and lower resting heart rate (HR) than inactive men. A postexercise hypotensive response was observed among subjects in the 70% and 50% V˙o2 max conditions, accompanied by baroreceptor reflex inhibition in the 70% condition. Systolic pressure was lower during mental arithmetic and during recovery from the speech task in the high‐intensity than in the control group. Diastolic pressure was lower following mental arithmetic in the high‐intensity group. No differences in HR reactivity, electrodermal, or respiratory parameters were observed, but baroreceptor reflex sensitivity was inhibited during mental arithmetic. The results are discussed in relation to previous reports of suppressed cardiovascular reactivity to mental stress tests following vigorous exercise and the role of stress‐related processes in the antihypertensive response to physical training.
Preferential neural processing of attended stimuli in attention‐deficit hyperactivity disorder and normal boys
Authors: SATTERFIELD JAMES H. , SCHELL ANNE M. , NICHOLAS THOMAS 
Published: February 2007

AbstractEvent‐related auditory and visual potentials were recorded from 36 attention‐deficit hyperactivity disorder (ADHD) and 35 normal 6‐year‐old subjects engaged in a two‐choice discrimination task. When normal subjects attended to stimuli in a given modality, enhanced negative (N2) and positive (P3b) responses (as compared with responses to nonattended stimuli) were found for auditory and visual target stimuli. In contrast, when ADHD subjects attended, little or no enhanced negative responses were found in either modality, and enhanced positive P3b responses were found only in response to visual target stimuli. Auditory N1, N2, and P3b and visual N2 amplitudes to attended target stimuli were significantly reduced in ADHD subjects as compared with normal subjects. No between‐group differences were found for responses to nonattended stimuli. Both amplitude and latency abnormalities indicate that ADHD boys suffer from deficient preferential processing of attended stimuli. P3b and N2 abnormalities found here suggest deficiencies in two independent cognitive processes thought to be crucial to what we perceive, learn, and remember.
The relationship of sweat gland count to electrodermal activity
Authors: FREEDMAN LAUREN W. , SCERBO ANGELA SCARPA , DAWSON MICHAEL E. , RAINE ADRIAN , McCLURE WILLIAM O. , VENABLES PETER H. 
Published: February 2007

AbstractThis study assessed whether greater skin conductance activity at the distal versus medial site (Scerbo, Freedman, Raine, Dawson, & Venables, 1992) is attributable to a greater number of active (open) sweat glands at the distal site. The number of sweat glands was measured using the Palmar Sweat Index (PSI). Twenty‐four subjects were exposed to 10 auditory stimuli. Electrodes were placed on the fore and middle fingers of each hand, using distal sites on one hand and medial sites on the other. The PSI was measured at the medial and distal phalanges adjacent to the electrode placement sites. The distal site contained more open and total sweat glands. Open gland count had the strongest correlations with skin conductance. Multivariate analyses of covariance revealed that site effects for nonspecific and orienting response frequency and trials to habituation were associated with site differences in open glands. Skin conductance measures and the PSI reveal greater electrodermal activity at the distal site. In addition, the number of open glands may be a useful measure related to electrodermal response frequency when polygraph measurement is unavailable.