bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discrimination of Sensorimotor EEG (12–15 Hz) Activity: A Comparison of Response, Production, and No‐Feedback Training Conditions
Authors: Cinciripini Paul M. 
Published: February 2007

ABSTRACTThe current study was concerned with the discrimination of 12–15 Hz (15μV) surface cortical EEG, recorded over the dominant hemisphere. This EEG bandwidth is sometimes called the SMR (sensorimotor rhythm), and has been associated with seizure reduction. Thirty‐six normal subjects were divided into three groups and exposed to three methods of discrimination training: response feedback, production feedback, and no‐feedback control. In the initial assessment session, all subjects were asked to detect the presence of SMR by pressing a response button in the absence of feedback. Over the next 4 training sessions, the control group continued without feedback, while the response feedback group received feedback (tone) for correct discriminations, and the production group received feedback for producing the SMR signal. Discrimination performance was assessed during a 15‐min no‐feedback test period, following each feedback segment. The final session took place two weeks after training had been completed and was the same as session 1. The results showed that both experimental groups improved discrimination accuracy over baseline, and relative to the control group. Performance of the groups at baseline was not significantly different, ranging between 16% and 29% correct. Peak performance during training showed that both experimental groups improved over baseline and relative to the control group, averaging 17%, 43% and 78% correct for the control, response and production feedback groups, respectively. In the final assessment, all groups deteriorated in performance, but the production group remained significantly above baseline levels. No changes in average SMR time or frontal EMG were noted. However, time spent in the occipital alpha bandwidth 8–13 Hz (25μV) did increase in the best discriminators. This may indicate some discrimination of subjective sensations associated with SMR discrimination training.
Alcohol and the Psychophysiological Detection of Deception
Authors: Bradley M.T. , Ainsworth D. 
Published: February 2007

ABSTRACTPsychophysiological detection of deception examinations were conducted on 40 subjects. Of these, 32 were “guilty” of a mock crime and 8 were innocent. Sixteen guilty subjects committed the crime while intoxicated and the remaining 16 committed the crime sober. These two groups of guilty subjects were subdivided such that half of each group was examined with the polygraph while intoxicated and the other half was examined while sober. Two questioning techniques were used in the examination, a Control Question Test and the Guilty Knowledge Test. Measures of skin resistance, heart rate and respiration were recorded. The principal findings were that alcohol intoxication during the crime reduced detectability with detection scores derived from the measurement of skin resistance responses on the Control Question Test and on the Guilty Knowledge Test. The analyses of guilt/innocent classifications, based on the detection scores, showed these classifications to be affected by alcohol intoxication.
The Visual ERP Predicts Clinical Response to Methylphenidate in Hyperactive Children
Authors: Halliday Roy , Callaway Enoch , Rosenthal Joseph H. 
Published: February 2007

ABSTRACTVisual ERP measures have been used to discriminate retrospectively between those hyperactive children who responded well to treatment with methylphenidate (MP) and those who were nonresponders. This study was designed to validate these ERP measures in a prospective study. Visual ERP data were obtained in 20 hyperactive children following 0.33 mg/kg methylphenidate (Ritalin) or a matching placebo. Parent, teacher and physician ratings were then obtained on these same doses in a subsequent double‐blind clinical trial. At the conclusion of the trials, children were classified as MP responders or nonresponders based on the pediatrician's blind ratings. Using criteria established in a prior study, a conjoint measure of amplitude and variability statistically discriminated nonresponders from responders. The two clinical groups did not differ on placebo. It was suggested that these predictors are sensitive to nonspecific pharmacological factors.
Heart Rhythm Control During Sleep in Ischemic Heart Disease
Authors: ŽEmaitytė Danguolė , Varoneckas Giedrius , Sokolov Eugene 
Published: February 2007

ABSTRACTThis paper deals with a computer‐aided study of heart rate (HR) control during different sleep stages in 20 healthy volunteers and 75 ischemic heart disease (IHD) patients. In healthy subjects, the parasympathetic HR control was increased and the sympathetic control decreased during stages 1, 2, 3, and 4. REM sleep was characterized by a marked decrease in parasympathetic and a slight elevation in sympathetic contribution. Typical, “reduced” and “paradoxical” HP sleep patterns (HRSPs) were observed in IHD patients. The typical HRSP was similar to that observed in healthy subjects; the reduced HRSP was characterized by HR constancy, and the paradoxical HRSP by an HR increase in stages 3 and 4, and a decrease in REM sleep. The reduced HRSP was associated with the more frequent occurrence of cardiac abnormalities during REM sleep. HR oscillations during stage 2 depended on periodic apnoea episodes and were associated with cardiac abnormalities such as more frequent heart failure and cerebral blood flow disturbances, and overweight.
Comparison of Eye Motion in Wakefulness and REM Sleep
Authors: Aserinsky Eugene , Joan A. Lynch , Mack Michael E. , Tzankoff Stephen P. , Hurn Estil 
Published: February 2007

ABSTRACTRapid eye movements (REMs) in sleep have been postulated to represent ocular activity directly related to the visual imagery of dreaming. In accord with this notion, there have been reports that the physiological characteristics of REMs are identical to those of waking saccades which occur in the absence of visual targets. Contradictory evidence is herein presented establishing that REMs are significantly slower than waking saccades of comparable amplitude, and that this slowdown is greater than can be attributed to either eye closure or to eye movements in total darkness. Furthermore, it is shown that in REM sleep, both small (5.5°) and large (11°) saccade‐like movements generate essentially the same maximal force and have the same velocity for the major portion of their trajectories. In sleep, therefore, there is probably a central inhibition of the saccade‐like REMs, especially of the large amplitude movements, thus leading to an uncoupling of the usual amplitude‐velocity relationship observed in the waking state.
Engaging Visual Stimuli and Reflex Blink Modification
Authors: Simons Robert F. , Zelson Michael F. 
Published: February 2007

ABSTRACTTwenty‐one college undergraduate subjects were provided discrete trials of visual foreground stimuli with varying interest value while an intense acoustic probe delivered during viewing was used to elicit the startle reflex. The foreground stimuli were 35 mm color slides containing photographs of nude male and female models (high interest) or a common household object (low interest). The results of this experiment, using adult subjects, replicate closely the findings of Anthony and Graham (1983) who studied four‐month old human infants in a similar paradigm. That is, when probe stimuli occurred on an auditory channel, reflex magnitude and onset latency were significantly inhibited while subjects were concurrently processing an attention‐engaging visual stimulus. The successful use of EOG techniques to record the eyeblink component of the startle reflex and capture its sensitivity to the attentional manipulation suggests that the probe startle paradigm may be readily put to use in a wide variety of psychophysiological laboratories.
A Further Analysis of Age and Sleep Deprivation Effects
Authors: Webb Wilse B. 
Published: February 2007

ABSTRACTSubjective, persistence/attention, precision, and cognitively demanding measures were obtained across two nights' sleep deprivation to compare the performance of 50–59 and 18–22 yr old men. The younger subjects had the larger subjective decrements while the older subjects had the larger decrements on the persistence tasks. The results were mixed on the precision and cognitively demanding tasks.
Changes in Heart Period, Heart‐Period Variability, and a Spectral Analysis Estimate of Respiratory Sinus Arrhythmia in Response to Pharmacological Manipulations of the Baroreceptor Reflex in Cats
Authors: McCabe Philip M. , Yongue Brandon G. , Ackles Patrick K. , Porges Stephen W. 
Published: February 2007

ABSTRACTThe purpose of the present study was to assess changes in heart period, heart‐period variance (HPV), and respiratory sinus arrhythmia (RSA) during manipulations of the baroreceptor reflex in anesthetized cats. Hypertension, induced via phenylephrine infusion, reflexly increases parasym‐pathetic activity and decreases sympathetic activity. Hypotension, produced by infusion of nitroprusside, leads to increased sympathetic activity and an inhibition of vagal influences on the heart. Specific autonomic contributions were assessed following administration of practolol, a β‐adrenergic blocker, or atropine methyl nitrate.Spectral analysis was used to quantify the component of HPV associated with respiration, i.e., RSA, which is proposed to be sensitive to vagal influences on the heart. The respiratory component of HPV is described by a statistic, V̂, which is the sum of the spectral densities of the heart period spectrum across the band of frequencies associated with normal respiration.Hypertension produced an increase in V̂ which was blocked by atropine infusion, but unaltered by beta‐adrenergic blockade. Hypotension decreased V̂ to near‐zero values which persisted after atropine and practolol infusion. These data suggest that V̂ is determined primarily by vagal factors. Correlations between V̂ and a previously used criterion measure of vagal tone further support this hypothesis. In contrast, heart period was sensitive to vagal and sympathetic factors. Heart period increases during hypertension were abolished with atropine and heart period decreases due to hypotension were eliminated by beta‐adrenergic blockade. These responses are consistent with the notion that heart period is under the control of both sympathetic and vagal factors. Since in an anesthetized preparation RSA is the major source of heart‐period variability, HPV responded similarly to V̂.The results suggest that the spectral estimate of RSA, V̂, is particularly sensitive to blood pressure induced reflexive changes in vagal efferent influences on the heart. It also appears that V̂ is less influenced by sympathetic factors than heart period, a commonly used estimate of vagal activity.
Pupillary Dilations in Movement Preparation and Execution
Authors: Richer Francois , Beatty Jackson 
Published: February 2007

ABSTRACTMovement‐related pupillary responses (MRPRs) were examined during self‐triggered finger flexions to determine the time course and extent of response‐related effects on this measure of general processing demands. MRPRs to self‐triggered finger movements began about 1.5 s before the response and peaked 0.5 s post‐response for simple movements. This dilation increased in amplitude and latency with the complexity of the movement as determined by the number of flexions executed. Peak pupillary amplitude was also sensitive to the force of the movement. The data establish the very large contribution of motoric processing demands to the pupillary response both before and after the onset of the movement.
Sleep Mentation in the Elderly
Authors: Fein George , Feinberg Irwin , Insel Thomas R. , Antrobus John S. , Price Leonard J. , Floyd Thomas C. , Nelson Mary A. 
Published: February 2007

ABSTRACTMentation reports were elicited from NREM and REM sleep in 18 normal elderly females. Transcribed reports were analyzed for word count, visual and auditory imagery, intention, and affect. Comparison with similarly analyzed data from 23 young adult women revealed no differences between young and elderly in narrative length (either REM or NREM). Both groups showed longer narratives from REM awakenings. With narrative length controlled, NREM‐REM differences in visual or auditory imagery, intention, or affect were non‐existent in the young and very small in the elderly, findings that contradict earlier results but are consistent with more recent controlled studies in young adults. The elderly subjects showed strikingly less visual imagery than young subjects in both NREM and REM reports. Further studies are required to determine whether the decreased incidence of visual imagery in the elderly results from a response bias or from differences in the mechanisms of visual imagery production in sleep, waking, or both.
Detectability in the Card Test as a Function of the Subject's Verbal Response
Authors: Horneman Christopher J. , O'Gorman J.G. 
Published: February 2007

ABSTRACTThe study compared, in a within‐subjects design, the effect on electrodermal responsiveness of the subject affirming, denying, or making no response to questions about the card selected in a laboratory test of deception. Contrary to previous findings, denying that a card had been selected led to greater responsiveness and an increased likelihood of correct detection.
Effects of Lateralized Presentations of Faces on Self‐Reports of Emotion and EEG Asymmetry in Depressed and Non‐Depressed Subjects
Authors: Davidson Richard J. , Schaffer Carrie Ellen , Saron Clifford 
Published: February 2007

ABSTRACTRecent data suggest that individuals with affective disorders show anomolies on various measures of cerebral lateralization and hemispheric activation. In this study, EEG was recorded from left and right frontal and parietal scalp regions during left and right visual field and foveal presentations of happy, sad and neutral faces in 10 depressed and 10 non‐depressed subjects. The sample was selected from a student population on the basis of scores on the Beck Depression Inventory. Faces were presented for 8 seconds and EOG was used to exclude trials associated with eye movements. Alpha activity from each of the leads during the middle 6 seconds of each trial was extracted for analysis. In addition, subjects were asked to rate each face on the degree to which it depicted various emotions, as well as the degree to which they experienced various emotions in response to each presentation. The results indicated that non‐depressed subjects report more happiness in response to RVF compared with LVF presentations of the identical faces while depressed subjects show the opposite pattern. Frontal EEG alpha asymmetry paralleled the subjective ratings of happiness for both groups and accounted for more than 50% of the variance in self‐reports of this emotion. Parietal asymmetry showed little relationship to subjective reports of emotion but did show systematic differences as a function of stimulus location, primarily due to changes in right parietal alpha. Finally, depressed subjects showed reciprocal relationships between frontal and parietal asymmetry while non‐depressed subjects showed a positive relationship between asymmetry in these regions. The implications of these data for cognitive dysfunction in depression are discussed.
Detection of the Heartbeat and Events in the Cardiac Cycle
Authors: Yates Aubrey J. , Jones Kathleen E. , Marie Gregory V. , Hogben John H. 
Published: February 2007

ABSTRACTIn previous studies the heartbeat has been defined in terms of individual components of the cardiac cycle (e.g., the R‐wave or the ventricular contraction) as specified by the experimenter, and subjects have been classified as nondetectors if they failed the task set by the experimenter. In this experiment 20 subjects were asked to judge whether a light flash occurring at one of six points within a single heart cycle was coincident with a heartbeat. It was found that the heartbeat was judged as being coincident with light flashes occurring between 200 and 400 ms after the R‐wave more frequently than with flashes coincident with the R‐wave or occurring 500 ms after it. There were marked individual differences in the patterns of responding indicating that a single criterion for heartbeat detection is not a satisfactory means of assessing detection ability.
A Controlled Investigation into the Measurement Properties of Two Circumferential Penile Strain Gauges
Authors: Richards Jeffrey C. , Bridger Brian A. , Wood Michael M. , Kalucy Ross S. , Marshall Villis R. 
Published: February 2007

ABSTRACTA Barlow‐type electromechanical strain gauge and an indium/gallium‐in‐rubber strain gauge were compared for linearity of output, replicability, stability, and sensitivity to temperature changes. Distension of the strain gauges was achieved by placing them on standard size glass dilators, while temperature changes were produced and monitored in a controlled environment. Both gauges demonstrated comparable and very linear outputs and both had high test‐retest reliability. Variations in temperature affected the outputs for both gauges, although for neither did they affect the degree of linearity between pen deflection and circumference. The electromechanical strain gauge was marginally less sensitive to temperature changes than the indium/gallium gauge, although for neither was the degree of error introduced of great practical significance. Although the output from the electromechanical strain gauge was slightly less stable over time than that from the indium/gallium gauge, when all variables were considered, the former gauge was marginally preferred over the latter.
The Effects of Semantic Priming and Word Repetition on Event‐Related Potentials
Authors: Rugg Michael D. 
Published: February 2007

ABSTRACTEvent‐related potentials (ERPs) were recorded during the performance of a lexical decision task, in which a proportion of the words were either semantic associates or repetitions of the preceding word. Reaction times were faster to both the second member of associated pairs (targets) and repeated words, with the latter facilitatory effect being more than twice that of the former.ERPs to the semantic primes were more negative‐going than those to targets. This difference peaked around 400–450 ms after stimulus onset. Comparison of unrepeated and repeated words revealed a larger and temporally more extended difference, with a similar scalp topography.The prime‐target differences are interpreted as a further example of the sensitivity of the ‘N400’ component of the ERP to semantic relationships between words. The differences between the repetition and priming effects in ERPs are considered equivocal with respect to the view that the associated behavioural effects are caused by different cognitive mechanisms.
Nuisance Sources of Variance in Principal Components analysis of Event‐Related Potentials
Authors: Möcks Joachim , Verleger Rolf 
Published: February 2007

ABSTRACTThis paper describes a method of disentangling different sources of variance contributing to component extraction in Principal Components Analysis (PCA) of event‐related potentials. Those sources not of interest for a given experiment may be easily discarded prior to component extraction. A real data example is presented for comparison of the different approaches, showing advantages for the new methods. They also exhibited more success in detecting experimental effects as shown in subsequent analysis of variance procedures on component scores. In the latter framework, various issues of validity of subsequent testing procedures for all principal component approaches are addressed theoretically as well as empirically by a split‐sample cross‐validation study. It is claimed that data‐adaptive computation of component scores does not constitute a crucial issue. Finally, a bootstrap simulation provides evidence that the methods proposed are superior to the usual PCA approach in capability and relibility in the assessment of experimental effects.
Electrophysiological Study of Intrahemispheric S‐R Compatibility Effects Elicited by Visual Directional Cues
Authors: Ragot Richard , Lesevre Nicole 
Published: February 2007

ABSTRACTThe effects of stimulus‐response (S‐R) spatial compatibility on reaction time (RT) and P300 component latency were studied, in order to determine whether spatial conflict effects can occur within a single cerebral hemisphere, and whether there are differences between hemispheres regarding such effects. Two choice RT experimental conditions were employed: I) an extrafoveal condition, in which stimuli (small arrows pointing either to the right or to the left) appeared laterally in one visual hemifield, the responses being given with the hand situated on the same side; likewise with the opposite hemifield and hand (cond. I); and II) a foveal condition, in which the same type of stimuli appeared centrally on the fovea, the response being given successively with both hands (cond. II). In either case, the color of the stimuli (cue information) determined which finger (forefinger or ring finger) of the same hand would deliver the response. Thus, the cue was either compatible, or not, with the stimulus orientation (arrows). In each condition, the four possible stimulus combinations, according to direction and color of the arrows, were presented at random.Results showed that: 1) in the extrafoveal condition, S‐R compatibility effects were observed in each single hemisphere, and were reflected both by RT and by P300 latency; 2) both hemispheres reacted in the same way to the spatial conflict; and 3) foveal vision increased the overall effect of the conflict on both P300 latency and RT.
Electroretinograms Reveal No Evidence for Centrifugal Modulation of Retinal Inputs During Selective Attention in Man
Authors: Mangun G.R. , Hansen J.C. , Hillyard S.A. 
Published: February 2007

ABSTRACTEason, Oakley, and Flowers (1983, Physiological Psychology, 11, 18–28) have recently described changes in the B‐wave and after‐potential of the human electroretinogram (ERG) during spatial selective attention. These results suggested that centrifugal modulation of retinal input may play a role in visual attention. We investigated this effect in two experiments in which subjects attended to sequences of flashes in one visual half‐field while ignoring similar flashes in the opposite half‐field. Visual event‐related potentials (ERPs) were recorded from electrodes placed at periorbital and scalp sites, while the ERG was simultaneously recorded using a gold‐foil electrode contacting the cornealscleral surface of the right eye. Selective visual attention was evident in an enhancement of the scalp‐recorded N150 component of the visual ERP to flashes in the attended half‐field. However, no effect of attention was observed on the B‐wave or after‐potential of the ERG. Long‐latency positive shifts related to attention were demonstrated in the corneal‐scleral recording and are discussed with respect to volume‐conducted brain activity.