bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intracranial topography of event‐related potentials (N400/P600) elicited during a continuous recognition memory task
Authors: GUILLEM FRANçOIS , N'KAOUA BERNARD , ROUGIER ALAIN , CLAVERIE BERNARD 
Published: February 2007

AbstractTo isolate the anatomical locus of the neural activity most important for generating or modulating the scalp‐recorded N400 and P600 components elicited during continuous recognition memory tasks, intracranial event‐related potentials (ERPs) were recorded from medial and lateral aspects of the temporal, frontal, parietal, and occipital lobes in 25 patients undergoing stereoelectroencephalography for seizure localization. Large‐amplitude and polarity‐inverted ERPs were recorded from various temporal, frontal, and parietal structures, whereas the memory‐related ERP modulation assessed by the ERP repetition effect was present only in those brain areas that play the most important role in memory processing. These data suggest that the scalp‐recorded N400 and P600 components may represent the most readily observable aspect of synchronous activity occurring across widely distributed brain structures and neural systems underlying different cognitive mechanisms, which all contribute to some aspect of information processing during recognition memory.
Mismatch negativity to auditory stimulus change recorded directly from the human temporal cortex
Authors: KROPOTOV J. D. , NÄÄÄNEN R. , SEVOSTIANOV A. V. , ALHO K. , REINIKAINEN K. , KROPOTOVA O. V. 
Published: February 2007

AbstractMismatch negativity (MMN) is an event‐related potential (ERP) component elicited by any discernible change in a repetitive sound even in the absence of attention. Previous studies have established that MMN is generated by change detection in a process comparing the deviant sensory input with the neural memory trace encoding the physical features of the repetitive sound. In the present study, we recorded MMNs to tonal frequency changes directly from the human temporal cortex of patients with electrodes implanted in the brain for diagnosis and therapy. The intracranially recorded MMN was found to be attention independent and modality specific. It was confined to a rather small area in temporal cortex, which was different from the structures where attention‐dependent N2 and P3 responses to the frequency change could be recorded.
Dimensional analysis of resting human EEG II: Surrogate‐data testing indicates nonlinearity but not low‐dimensional chaos
Authors: PRITCHARD WALTER S. , DUKE DENNIS W. , KRIEBLE KELLY K. 
Published: February 2007

AbstractSurrogate‐data testing has recently been proposed as one way to detect the presence of nonlinearity and low‐dimensional chaos in experimental time series. Such testing involves estimating correlation dimension for both the original data and surrogate data from which nonlinearity has been removed. We applied such testing to the same resting, eyes‐closed, and eyes‐open electroencephalogram (EEG) data set that was originally analyzed using dimension estimation applied only to the original data (Pritchard & Duke, 1992). Two kinds of surrogate‐data sets had higher estimated dimension and poorer saturation. This indicates that the normal resting human EEG is nonlinear and therefore not a linear‐stochastic system. Because nearly complete saturation at some loci was not differentially affected by the surrogate‐data procedures, our results also indicate that the normal resting human EEG is high dimensional and does not represent low‐dimensional chaos.
Fear conditioning, preparedness, and the contingent negative variation
Authors: REGAN MARTIN , HOWARD RICK 
Published: February 2007

AbstractPsychophysiological research on preparedness has previously focused on autonomic nervous system parameters. The present study used electrocortical indices of fear conditioning. Subjects (n= 10) were tested under fear‐relevant and fear‐irrelevant conditions (1 week apart, order of conditions counterbalanced). Each condition comprised acquisition and extinction sessions. The contingent negative variation (CNV) was elicited in anticipation of forewarned slides (fear relevant: small animals; fear irrelevant: landscapes). In acquisition, reinforced conditioned stimulus (CS+) (but not nonreinforced conditioned stimulus [CS‐]) slides were followed by white noise as an unconditioned stimulus (UCS). In extinction, the UCS was omitted. In the fear‐relevant condition, CNV amplitude was significantly larger for CS+ than CS‐ in both acquisition and extinction. In the fear‐irrelevant condition, CNV differentiation between CS+ and CS‐ was weak in both sessions. CNV was significantly larger in the fear‐relevant than in the fear‐irrelevant condition, for CS+ but not CS‐. The findings are consistent with a preparedness interpretation and suggest that CNV under such circumstances may represent an automatic affective response to fear‐relevant stimuli. Electrocortical measures could be particularly useful in examining information processing mechanisms in phobia and cognition‐affect relationships generally.
Counteracting driver sleepiness: Effects of napping, caffeine, and placebo
Authors: HORNE J. A. , REYNER L. A. 
Published: February 2007

AbstractSleepy drivers should “take a break,” but the efficacy of feasible additional countermeasures that can be used during the break is unknown. We examined a shorter than 15 min nap, 150 mg of caffeine in coffee, and a coffee plalcebo, each given randomly across test sessions to 10 sleepy subjects during a 30‐min rest period between two 1‐hr monotonous early afternoon drives in a car simulator. Caffeine and nap significantly reduced driving impairments, subjective sleepiness, and electroencephalographic (EEG) activity indicating drowsiness. Blink rate was unaffected. Sleep during naps varied, whereas caffeine produced more consistent effects. Subjects acknowledged sleepiness when the EEG indicated drowsiness, and driving impairments were preceded by self‐knowledge of sleepiness. Taking just a break proved ineffective.
The role of the right hemisphere in the physiological and cognitive components of emotional processing
Authors: Spence Sarah , Shapiro David , Zaidel Eran 
Published: February 2007

AbstractRight hemisphere specialization for emotional processing was investigated using behavioral and psychophysiological methods, Fifty undergraduates were shown slides depicting negative emotional and neutral scenes briefly lateralized to the right or left cerebral hemispheres and asked to categorize each as emotional or neutral. Pulse volume and heart rate (HR) measured physiological processing and reaction time measured cognitive processing. The largest vasoconstriction responses and HR deceleration were obtained for emotional items in the right hemisphere. However, reaction time failed to show right hemisphere superiority in perceptual/cognitive processing, demonstrating instead slowest responses to emotional stimuli presented to the right hemisphere together with evidence for left hemisphere competence. Selective right hemispheric activation in autonomic responses, combined with the lack of right hemisphere specialization in the cognitive task, suggests that the physiological response system rather than the perceptual/cognitive system is the locus of the right hemisphere superiority for emotion.
Picture media and emotion: Effects of a sustained affective context
Authors: BRADLEY MARGARET M. , CUTHBERT BRUCE N. , LANG PETER J. 
Published: February 2007

AbstractPleasant, neutral, or unpleasant pictures were presented in a continuous series, and the effects of repetitive exposure to pictures of the same affective valence were assessed in somatic (corrugator electromyographic [EMG] activity) and visceral (heart rate and skin conductance) systems. Probe stimuli (startle or reaction time probes) were presented to index emotional and attentional concomitants of processing. Affective discrimination was maintained across time in all response systems, and sensitization was found for the corrugator EMG response. Responses to reaction time probes indexed differences in attentional allocation as a function of cognitive and affective variables in this paradigm. Taken together, the data suggest that presentation of a series of affective pictures of similar valence produces emotional reactions that are either maintained or sensitized across the temporal intervals used here but that do not habituate.
Is an apple a fruit? Semantic relatedness as reflected by psychophysiological responsivity
Authors: BEN‐SHAKHAR GERSHON , FROST RAM , GATI ITAMAR , KRESH YIFAT 
Published: February 2007

AbstractIn the present study, we investigated orienting response generalization across various types of semantically related stimuli. Four experiments, based on a modified version of the guilty knowledge technique, were designed to examine whether semantic relations based on abstract features are reflected by electrodermal responsivity. No generalization across coordinates was obtained, but a moderate degree of generalization was demonstrated between a word and its superordinate category (e.g., table‐furniture) and between a word and its synonym. Complete generalization occurred from a verbal label of an object to its pictorial representation, and vice versa. These results are compatible with our proposal that partial identification of the test stimulus as relevant is a necessary condition for generalization in the guilty knowledge technique.
The varying time courses of attentional and affective modulation of the startle eyeblink reflex
Authors: VANMAN ERIC J. , BOEHMELT ANDREAS H. , DAWSON MICHAEL E. , SCHELL ANNE M. 
Published: February 2007

AbstractIn previous research on modulation of the startle eyeblink reflex, emotional effects have been demonstrated only at late probe positions, whereas attentional effects have been found at both early and late positions but only when the prepulses were affectively neutral. In Experiment 1, participants viewed emotionally valenced pictures and were instructed to attend to the duration of half of the slides. Affective modulation of the startle eyeblink occurred at long lead intervals, but attentional modulation also occurred late. In Experiment 2, participants viewed the same slides used in Experiment 1 but were instructed to attend to the duration of only the positive or the negative slides. Affective modulation occurred at both early and late probe positions, whereas attentional effects occurred only following slide offset. Early (250 ms) affective modification of startle eyeblink has not been previously reported. These results suggest that the time courses of emotional and attentional modulation of startle are variable and can occur at both early and late startle probe positions, depending on task requirements.
Memory for words and novel visual patterns: Repetition, recognition, and encoding effects in the event‐related brain potential
Authors: VAN PETTEN CYMA , SENKFOR AVA J. 
Published: February 2007

AbstractEvent‐related potentials (ERPs) were recorded during initial study and recognition of words and novel visual patterns. Words and patterns yielded similar recognition results that discriminated correctly recognized old items from correct new items, incorrect old items, and incorrect new items. The study phase data included a number of dissociations between words and patterns. Occasional repeated items yielded faster reaction times for both stimulus types but a late positive ERP repetition effect for words only. The study phase data differentiated words that would later be recognized versus unrecognized, but the patterns did not yield a similar encoding effect. Moreover, the study phase positivity contingent on subsequent recognition was restricted to words that received a positive semantic judgment during study. The functional relationships among the repetition, recognition, and encoding effects are discussed.
Influence of beliefs about heart rate and actual heart rate on heartbeat counting
Authors: RING CHRISTOPHER , BRENER JASPER 
Published: February 2007

AbstractThe heartbeat counting task is used widely to assess the ability to perceive cardiac sensations. However, performance on this task may be determined by processes other than sensitivity to cardiac stimuli. Beliefs about the effects of postural and exercise challenges on heart rate were assessed by questionnaire prior to performing the heartbeat counting task, and then actual heart rate was manipulated during the counting task by changes in posture and exercise. On average, counted heart rates were closer to beliefs about heart rate than to actual heart rate. Hierarchical multiple regression analyses indicated that (a) believed heart rates predicted counted heart rates while controlling for actual heart rates and (b) actual heart rates also predicted counted heart rate while controlling for heart rate beliefs. These data suggest that the rate of heartbeat counting is influenced by beliefs about heart rate and by the processing of cardiac sensations.
Does the heart know what the ears hear? A heart rate analysis of auditory selective attention
Authors: VAN DER MOLEN MAURITS W. , SOMSEN RIEK J. M. , JENNINGS J. RICHARD 
Published: February 2007

AbstractBetween‐ and within‐channel auditory selective attention were examined by presenting subjects with tone pips randomly to opposite ears; some pips had a slightly different pitch. Subjects were instructed to count rare, deviant tone pips at one ear and ignore all input to the other ear. Heart rate was sampled twice: once for the attended tone pips and once for the nonattended stimulus series. Heart rate responded differently to attended tone pips. While subjects were waiting for the rare stimulus to occur, heart rate slowed until the deviant stimulus was detected, which was followed by heart rate acceleration. Anticipatory heart rate deceleration was largely absent for nonatended series, and rare tone pips presented at the nonattended ear were not followed by acceleratory recovery. All tone pips elicited cardiac cycle time effects, that is, stimuli presented at short delays after the R wave prolonged the concurrent interbeat interval more than stimuli presented later. The cardiac cycle time effect was not altered by stimulus relevance (attended vs. nonattended) or significance (standard vs. rare). These results suggest that all stimuli receive preliminary perceptual analysis, but only attended stimuli are processed for further evaluation.
Principal component analysis of event‐related potentials: Misallocation of variance revisited
Authors: ACHIM ANDRÉA , MARCANTONI WALTER 
Published: February 2007

AbstractMisallocating variance, in event‐related potential analysis, refers to attributing an experimental effect to components not actually affected. A vector interpretation of the relationship between mathematically derived and true underlying components shows that misallocation depends exclusively on incorrect identification of the affected component. Simulations, using seven imperfect rotations, confirmed all predictions from the vector interpretation concerning the presence, direction, and size of misallocated variance. Contrary to principal component analysis (PCA), Möucks's topographic component model (TCM) is not subject to rotation problems. These two methods were compared over 100 simulations in which the components had constant waveforms and topographies across participants. The group effect was always detected, but only PCA and not TCM showed significance on other components, except when their random weights happened to differ between groups.
Manipulating affective state using extended picture presentations
Authors: SUTTON STEVEN K. , DAVIDSON RICHARD J. , DONZELLA BONNY , IRW1N WILLIAM , DOTTL DARREN A. 
Published: February 2007

AbstractSeparate, extended series of positive, negative, and neutral pictures were presented to 24 (12 men, 12 women) undergraduates. Each series was presented on a different day, with full counterbalancing of presentation orders. Affective state was measured using (a) orbicularis oculi activity in response to acoustic startle probes during picture' presentation, (b) corrugator supercilii activity between and during picture presentation, and (c) changes in self‐reports of positive and negative affect. Participants exhibited larger eyeblink reflex magnitudes when viewing negative than when viewing positive pictures. Corrugator activity was also greater during the negative than during the positive picture set, during both picture presentation and the period between pictures. Self‐reports of negative affect increased in response to the negative picture set. and self‐reports of positive affect were greatest following the positive picture set. These findings suggest that extended picture presentation is an effective method of manipulating affective state and further highlight the utility of startle probe and facial electromyographic measures in providing on‐line readouts of affective state.
Cardiovascular responses during effortful active coping and acute experience of anger in women
Authors: BONGARD STEPHAN , PFEIFFER JUTTA S. , AL'ABSI MUSTAFA , HODAPP VOLKER , LINNENKEMPER GABI 
Published: February 2007

AbstractThis study addresses the question of whether effortful active coping and anger provocation add in their effects on cardiovascular responses. Heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) responses of 64 female students were collected during an active versus nonactive coping task with and without provocation. After a baseline period, women did mental arithmetic (active coping) or read numbers aloud (nonactive coping). Half of each group was then additionally provoked. Ratings of the emotional states (Positive and Negative Affect Scale) indicate that provocation led to an increase in anger, but not in fear or negative or positive affect. Effortful active coping and provocation elevated cardiovascular activity. Although active coping enhanced all cardiovascular variables, provocation particularly affected HR and DBP. The effects of active coping and provocation on HR and DBP but not on SBP were additive and probably were produced by different physiological mechanisms.
On the detection of auditory deviations: A pre‐attentive activation model
Authors: SCHRÖGER ERICH 
Published: February 2007

AbstractThe conscious perception of infrequent deviant sounds occurring in a series of frequent standard sounds may in part be based on the output of an obligatorily operating deviance detection system. This system encodes invariances inherent to the recent auditory stimulation into short‐lived representations of auditory sensory memory and compares each actual input with these representations. The underlying processes may be regarded as preattentive in the sense that they do not rely on the explicit intention of a person to detect deviants and that they may be active even in the absence of attention (although they may be prone to attentional modulations). The output of this feature‐specific preattentive deviance detection system fuses into an integrated mismatch signal that in turn may activate subsequent processes that result in the triggering of a motor response.
Temporal characteristics of auditory sensory memory: Neuromagnetic evidence
Authors: MCEVOY LINDA , LEVÄNEN SARI , LOVELESS NORMAN 
Published: February 2007

AbstractWe investigated the temporal dependencies of N100m, the most prominent deflection of the auditory evoked response, using whole‐head neuromagnetic recordings. Stimuli were presented singly or in pairs (tones in the pair were separated by 210 ms) at interstimulus intervals (ISIs) of 0.6–8.1 s. N100m to single stimuli and to the first tone of the pair had similar temporal recovery functions, plateauing at ISIs of 6 s. N100m to the second tone in the pair, which was smaller than that to the first except with short ISIs, plateaued with ISIs of about 4 s. Source analysis revealed that the N100m could be decomposed into two sources separated by about 1 cm on the supratemporal plane. The recovery function of the posterior source was not affected by stimulus presentation, whereas that of the anterior source was. Activity in the anterior area appears to reflect the effects of temporal integration. We relate these results to auditory sensory memory.
The pupillary light reflex cannot be used to measure sleepiness
Authors: RANZIJN ROB , LACK LEON 
Published: February 2007

AbstractThe pupillary light reflex (PLR) has been considered by some researchers to be responsive to changes in levels of sleepiness. However, no previous studies have tested this hypothesis with the dramatic variation of sleepiness across a complete circadian cycle. In this experiment, 20 normal individuals (age: 18–48 years) underwent a 27‐hr constant routine, during which they were kept awake except for a 15‐min nap opportunity every hour. Sleepiness was assessed both subjectively, by the Stanford Sleepiness Scale, and objectively, by a modified version of the Multiple Sleep Latency Test. The PLR in response to a flash of light was recorded every 2 hr, immediately before a nap period. Results showed that baseline pupil diameter became smaller with progressive sleep restriction, but there were no changes in any of the parameters of the PLR despite significant fluctuations in sleepiness. Some of the changes in the PLR were significantly related to changes in baseline pupil diameter. When baseline diameter was partialled out, there was still no effect of sleepiness on the PLR. The results suggest that the PLR cannot be used as a measure of sleepiness.
P300 event‐related potential heritability in monozygotic and dizygotic twins
Authors: KATSANIS JOANNA , IACONO WILLIAM G. , MCGUE MATTHEW K. , CARLSON SCOTT R. 
Published: February 2007

AbstractThe present study examined the heritability of the P3 waveform and the N1, P2, and N2 components by assessing the visual event‐related potential (ERP) of 30 monozygotic (MZ) and 34 dizygotic (DZ) twin pairs. Electroencephalogram activity was recorded from Pz, P3, and P4 scalp sites while individuals performed a reaction time task involving two conditions differing in difficulty. Genetic modeling indicated substantial genetic influence on P3 amplitude, P3 latency, and manual reaction time for the difficult condition. No significant heritability was found for the latency of P3 or manual reaction time for the easy condition, but P3 amplitude was heritable for this condition. The amplitude of the early components (N1, P2, and N2) was heritable, but no significant genetic influences were found for the latency of these components. Compared with the DZ twins, the greater similarity of the MZ pairs on the event‐related potential measures was not due to their greater similarity in either head dimensions or mental ability, despite the facts that IQ scores were weakly correlated with P3 and N2 amplitude and that amplitude and latency were related to some measures of head size. These findings suggest that P3 amplitude and the amplitude of earlier ERP components are under partial genetic control, supporting the notion that these ERP components could perhaps be used to identify genetic risk for psychopathology.