bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suspense and surprise: On the relationship between expectancies and P3
Authors: VERLEGER ROLF , JASKOWSKI PIOTR , WAUSCHKUHN BERND 
Published: February 2007

AbstractFew theories of the P3 component have emphasized the distinction between its parietal and frontocentral parts. This study used a new paradigm for testing the predictions that the parietal P3 is evoked by awaited stimuli (suspense) and the frontal P3 by unexpected stimuli (surprise). Subjects had to make simple responses whenever a yellow ring appeared. This signal appeared on the screen within a clock, most frequently when the pointer was at 12 o'clock (every 6s) but sometimes also at other times. The suspense process should therefore have its minimum shortly after 12 o'clock and then steadily increase until 12 o'clock, and the parietal P3 should accordingly be smallest with stimuli shortly after 12 o'clock, then gradually increase and be largest with 12 o'clock stimuli. Further, the stimuli presented at times other than 12 o'clock should evoke large frontal P3s because they were unexpected. The results confirmed parts of these predictions. A frontocentral and a parietocentral component could indeed be discerned. The frontal P3 was largest with non‐12 o'clock stimuli, whereas the parietal P3 was large with all stimuli. The parietal result was not predicted, but these results taken together pose more problems for the usual view, which assumes that the parietal P3 is evoked by unexpected stimuli, than for our assumption that the parietal P3 reflects suspense, and the frontocentral P3 reflects surprise. Generalizing to other paradigms, we assume that different topographies of P3 in different paradigms or in differnt groups of subjects might be due to different mixtures of these two components.
Nonconscious associative learning: Pavlovian conditioning of skin conductance responses to masked fear‐relevant facial stimuli
Authors: ESTEVES FRANCISCO , PARRA CRISTINA , DIMBERG ULF , ÖHMAN ARNE 
Published: February 2007

AbstractWe examined the possibility of nonconscious associative learning in a context of skin conductance conditioning, using emotional facial expressions as stimuli. In the first experiment, subjects were conditioned to a backwardly masked angry face that was followed by electric shock, with a masked happy face as the nonreinforced stimulus. In spite of the effectively masked conditioned stimuli, differential conditioned skin conductance responses were observed in a subsequent nonmasked extinction phase. This effect could not be attributed to differential sensitization or pseudo‐conditioning. In the second experiment, the differential responding during extinction was replicated with angry but not with happy faces as conditioned stimuli. It was concluded that with fear‐relevant facialexpressions as the conditioned stimulus, associative learning was possible even in conditions where the subjects remained unaware of the conditioned stimulus, associative learning was possible even in conditions where the subjects remained unaware of the conditioned stimulus and its relationship to the unconditioned stimulus.
Brain event‐related potentials to complex tones in depressed patients: Relations to perceptual asymmetry and clinical features
Authors: BRUDER GERARD E. , TENKE CRAIG E. , STEWART JONATHAN W. , TOWEY JAMES P. , LEITE PAUL , VOGLMAIER MARTINA , QUITKIN FREDERIC M. 
Published: February 2007

AbstractBrain event‐related potentials (ERPs) to probe tones in a dichotic complex tone test were recorded from right‐handed depressed patients (n= 44) and normal subjects (n= 19) at homologous sites over left and right hemispheres (F3, F4; C3, C4; P3, P4; O1, O2). There were no differences between groups in N1 or P2 amplitude, but patients had smaller P3 amplitude than did normal subjects. Depressed patients failed to show either the left ear advantage or behavior‐related hemispheric asymmetry of P3 seen for normal subjects. Depressed patients also showed less differences in hemispheric asymmetry between same and different judgments. These findings indicate that the abnormal behavioral asymmetry for dichotic pitch discrimination in depressed patients reflects a reduction in hemispheric asymmetry and is related to relatively late stages of cognitive processing.
Spatial orienting and focused attention in attention deficit hyperactivity disorder
Authors: NOVAK GERALD P. , SOLANTO MARY , ABIKOFF HOWARD 
Published: February 2007

AbstractSeventeen children with attention deficit disorder (ADHD) and 10 normal controls performed two tasks while event‐related potentials were recorded. ADHD subjects took part in two more sessions under methylphenidate (MP) or placebo. In the spatial orienting task, invalidly cued targets elicited a longer reaction time (RT) and a P3 that was longer in latency and greater in amplitude than did validly cued targets. Performance was similar for both groups, but the early portion of P3 (300–400 ms) was lower in amplitude for invalidly cued targets in ADHD subjects. MP increased accuracy without affecting RT and shortened P3 peak latency and increased the amplitude of its early portion. In the focused attention task, accuracy was greater for controls and MP, but there were no RT differenees. Attended stimuli elicited greater amplitude P1, N1, and P3 than did nonattended stimuli, but these measures were unaffected by diagnosis or medication.
The effect of lorazepam on memory and event‐related potentials in heavy and light social drinkers
Authors: NICHOLS JENNIFER M. , MARTIN FRANCES 
Published: February 2007

AbstractTo investigate the effects of heavy social drinking on sober cognitive processing, event‐related potentials were recorded from 13 heavy social drinkers and 13 light social drinkers in the presence and absence of a pharmacological challenge (i.e., lorazepam). Event‐related potentials were elicited by a task reuqiring continuous recognition memory for visually presented words. The heavy social drinkers exhibited shorter P2 latencies than the light in the task) versus “new” words. Lorazepam increased motor reaction time to correctly identified old words and produced a deficit in recognition memory only in the light social drinkers. Light social drinkers had an increased P300 latency anda larger P300 amplitude to new words in the lorazepam treatment. The differences in cognitive functioning evident between heavy and light social drinkers were reflected in event‐related potential deviations and appear to indicate a tolerance in heavy social drinkers to the effects of lorazepam.
A comparison of the electrophysiological effects of formal and repetition priming
Authors: Doyle Michael C. , Rugg Michael D. , Wells Tony 
Published: February 2007

AbstractThree experiments investigated the electrophysiological consequences of repetition (e.g., scandal‐scandal, buple‐buple) and formal (e.g., scan‐scandal, bup‐buple) priming using words and nonwords. In each experiment, repetition and formal priming resulted in positive‐going shifts in the event‐related potential (ERP) that onset at approximately 200 ms poststimulus and were initially of similar magnitude. Subsequently, the repetition effect became larger than the formal priming effect. Although the word and nonword formal priming effects and the nonword repetition effects were greatest over midline and right hemisphere sites, the word repetition effects were greatest over the midline. It is suggested that the positive‐going shift seen in the repetition and formal priming conditions was a modulation of the well‐documented N400 component of the ERP. The topographic differences between the priming effects may have reflected differences in the nature of the representations to which cognitive operations are applied rather than differences in the nature of the operations themselves.
Lateralized startle probes in the study of emotion
Authors: Bradley Margaret M. , Cuthbert Bruce N. , Lang Peter J. 
Published: February 2007

AbstractTwo experiments are reported in which affective modulation of the startle reflex elicited by monaurally presented acoustic probes was further examined. An earlier study in our laboratory obtained significant modulation by effect for probes presented to the left ear, but no significant effect for probes presented to the right ear Experiment 1 replicated the procedures used in that experiment and obtained the same pattern of effects. Experiment 2 changed the presentation of monaural probes from a blocked to a mixed presentation and again obtained a similar pattern. Modulatory differences in reflex magnitude between pleasant and unpleasant stimuli were consistently large and reliable for reflexes elicited by left ear probes but weak and unreliable for reflexes elicited by right ear probes.
Ambulatory monitoring of the impedance cardiogram
Authors: Willemsen Gonneke H. M. , DeGeus Eco J. C. , Klaver Coert H. A. M. , VanDoornen Lorenz J. P. , Carrofl Douglas 
Published: February 2007

AbstractThe wowing need for more advanced ambulatory monitoring has led lo the development of an ambulatory monitor for impedance cardiography (VU‐AMD). This paper presents two studies addressing the validity of the VU‐AMD. In the first study, the cardiovascular responses of 25 subjects during various conditions were simultaneously recorded with the VU‐AMD and a standard laboratory impedance device. Correlations between the responses of the ambulatory and laboratory devices were high, both inter and intraindividually, except lot stroke volume and cardiac output during exercise In the second study, 26 subjects underwent 24‐hr monitoring with the VU‐AMD. The values obtained with the VU‐AMD were realistic and varied in a predictable way over activity and posture. It is concluded that the VU‐AMD is a valid device for the measurement of systolic time intervals in real‐life situations but its applicability for absolute stroke volume and cardiac output determination remains lo he established.
Affective learning: Awareness and aversion
Authors: HAMM ALFONS O. , VAITL DIETER 
Published: February 2007

AbstractIn two studies, we investigated the influence of aversive and nonaversive reinforcers on startle reactivity, visceral responses, and self‐report during Pavlovian conditioning. Furthermore, we assessed how awareness of the stimulus contingencies affect conditioned discrimination in the different response systems. Conditioned potentiation of the startle response was only observed in the context of aversive learning. Moreover, blink potentiation occurred without awareness of the relationship between the conditioned and unconditioned stimulus. In contrast, skin conductance conditioning was independent of the aversiveness of the reinforcer and was only obtained for those individuals who could correctly verbalize the stimulus contingency in a postconditioning recognition test. Cardiac responses varied with the task demands of the situation and covaried with individual response stereotypes.
P300 topography and modality effects from a single‐stimulus paradigm
Authors: POLICH JOHN , HEINE MICHELE R. D. 
Published: February 2007

AbstractThe P300 event‐related brain potential (ERP) was elicited with auditory and visual stimuli in two different tasks. The oddball paradigm presented both target and standard stimuli; the single‐stimulus paradigm presented a target but no standard stimulus, with the intertarget interval the same as that for the oddball condition. Target probability was .20 for the oddball task, with target stimuli occurring at the same temporal frequency in the single‐stimulus paradigm. Scalp topography was assessed with 15 electrode locations. P300 amplitude was larger and latency was longer for the oddball than for single‐stimulus procedure. P300 from auditory stimuli was smaller and shorter in latency than that from the visual stimuli, and both modalities showed similar but not identical scalp topographies. The findings suggest that the single‐stimulus paradigm may be useful in experimental and applied contexts that require very simple ERP task conditions.
Views on how the electrical activity that the brain generates reflects the functions of different language structures
Authors: KUTAS MARTA 
Published: February 2007

AbstractHuman language is what it is because of its function and its implementation. We are far from understanding how language comprehension is carried out by the human brain. This task can be made easier by considering that evidence for the what and how of language comes from the study of linguistics, psychology, and neuroscience. The approach outlined herein describes how these different sources of evidence can be combined in studies of written and spoken sentence processing by using a measure of the brain's electrical activity. The outcome is a more temporally precise view of the analysis of language structures in our minds and brains.
Maternal exposure to influenza and cold in pregnancy and electrodermal activity in offspring: The Mauritius study
Authors: VENABLES PETER H. 
Published: February 2007

AbstractData are in conflict concerning whether a mother's exposure to influenza in pregnancy gives rise to an increased probability that her offspring will develop schizophrenia. In Northern Hemisphere studies, exposure to influenza and cold tend to be confounded. The present study, carried out in Mauritius, examines the effect of maternal exposure to the virus and separately to cold on aspects of electrodermal activity that have been shown in other studies to be related to schizophrenia. The findings are that maternal exposure to influenza in the second and third trimesters gives rise to children who at the age of 3 years show electrodermal hyperresponsivity, whereas exposure to cold in the same periods gives rise to children who tend to be hyporesponsive. In both instances, exposure tends to produce lower levels of tonic activity than in those not exposed to the virus or to cold.
Prepulse inhibition decreases as startle reactivity habituates
Authors: BLUMENTHAL TERRY D. 
Published: February 2007

AbstractIn the present study, I investigated the effect of stimulus repetition on human startle eyeblink reflex inhibition (PPI) by a prepulse. Participants were assigned to one of three groups (n= 14 each). in which they received 18 trials of (a) noise startle stimuli presented alone or preceded by 1000‐Hz tone prepulses, (b) startle stimuli presented alone, or (c) prepulses presented alone. All participants then received 18 more trials of startle stimuli presented alone or preceded by 1000‐Hz tone prepulses, followed by 6 trials of startle stimuli presented alone or preceded by 2000‐Hz tone prepulses. As trials progressed, startle eyeblink electromyogram magnitude habituated and PPI decreased. PPI was not affected by the repeated presentation of the prepulses alone but decreased with the repeated presentation of the startle stimulus alone. Changes in the frequency of the prepulse had no significant effect on PPI. These data suggest that the reduction of PPI that is seen across trials is not due to habituation of the prepulse but is related to startle reactivity in control trials, which is reduced by habituation.
The effect of emotional and attentional processes on blink startle modulation and on electrodermal responses
Authors: LIPP OTTMAR V. , SIDDLE DAVID A. T. , DALL PATRICIA J. 
Published: February 2007

AbstractEmotional accounts of startle modulation predict that startle is facilitated if elicited during aversive foreground stimuli. Attentional accounts hold that startle is enhanced if startle‐eliciting stimulus and foreground stimulus are in the same modality. Visual and acoustic foreground stimuli and acoustic startle probes were employed in aversive differential conditioning and in a stimulus discrimination task. Differential conditioning was evident in electrodermal responses and blink latency shortening in both modalities, but effects on magnitude facilitation were found only for visual stimuli. In the discrimination task, skin conductance responses, blink latency shortening, and blink magnitude facilitation were larger during to‐be‐attended stimuli regardless of stimulus modality. The present results support the notion that attention and emotion can affect blink startle modulation during foreground stimuli.
Application of drainage theory in the field
Authors: Towner G.D. , Youngs E.G. 
Published: February 2007

Abstract. The prediction of water‐table levels from groundwater theory for a drainage system in a uniform homogeneous soil was tested in an existing field system. Specially designed meters recorded water‐table heights and drain discharge with time. A comprehensive hydraulic conductivity survey was made below the water table.The results agreed with theory for water‐table heights up to about 300 mm above the mean drain level. The drainage above that level was larger than predicted, either because of an increased hydraulic conductivity (which could have been produced by subsoiling the previous year and would not have been picked up by die hydraulic conductivity measurements), or because of the presence of an older shallower lateral drainage system, broken and blocked, that was discovered during the work.Attention is drawn to the inadequacies of dip‐wells for monitoring rapid changes in water‐table levels and to the problem of sample size in hydraulic conductivity measurements, which if too small can lead to apparent variability.
Direct drilling compared with ploughing for winter wheat grown continuously and the effects of subsoiling
Authors: Hodgson D.R. , Hipps N.A. , Braim M.A. 
Published: February 2007

Abstract. Direct drilling was compared with mouldboard ploughing on a sandy clay loam using winter wheat as the test crop for a period of four years (1978/79 to 1981/82). The effect of short‐ and long‐term sequences of direct‐drilling on grain yield from 1981/85 was also investigated and in 1983/84 and 1984/85 the effect of soil loosening by a slant‐legged subsoiler, the‘Paraplow'. The range in annual mean yields was 7.19 to 9.32 t ha‐1. There were no significant differences in grain yield between direct‐drilling and ploughing except in 1979 when direct‐drilled wheat yielded 0.60 t ha‐1 more than wheat after ploughing. The number of years the land had been direct‐drilled had no effect on grain yield.Using a slant‐legged subsoiler on direct‐drilled land significantly reduced cone resistance and increased root density, but these effects were variable across the working width of the implement. Subsoiling did not increase yield in 1983/84, and in 1984/85 it reduced yield by 0.45 t ha‐1.Long‐term direct drilling of winter wheat on the Tickenham soil series is unlikely to result in a loss of yield provided straw is burnt and grass weeds are controlled.
Factors responsible for soil erosion hazard in submontane Punjab, India
Authors: Kukal S.S. , Sur H.S. , Gill S.S. 
Published: February 2007

Abstract. Various factors of soil erosion (erodibility of the soil, slope of the land and nature of the plant cover) were studied in a representative area of submontane Punjab. In the north‐eastern part of the area, slope steepness, slope length, convexo‐concave and concave slope patterns and sparse vegetation were the dominant factors governing erosion hazard. In the central and lower south‐western part of the area, high soil credibility and sparse vegetation were the most important factors.Rill erosion was positively correlated (r= 0.87) with slope steepness. The erodibility of the soil was strongly correlated (r= 0.98) with amounts of silt + very fine sand.In the area with steeper slopes, the lower segments of transects were prone to more erosion because of high credibility. Slope shapes such as convexo‐concave and concave could result in sloughing and greater erosion hazard if not properly protected. Slopes facing southwest were more prone to erosion than others because of more solar energy, greater aridity, less vegetation and concave shape.
Seasonal variation in the aggregate stability of downland soils
Authors: Blackman J. D. 
Published: February 2007

Abstract. Seasonal variation in the aggregate stability of chalk downland soils on the South Downs, East Sussex, UK, was studied using two measures of aggregate stability: water stable aggregation by wet sieving and dispersibility by a turbidimetric determination. Aggregate stability and organic carbon content were assessed on a monthly basis at 20 sites over a 19‐month period.Results indicated considerable variation in water stable aggregation over the time period studied but little variation in dispersibility. There were differences between sites mainly reflecting differences in organic carbon content. Soils with more organic carbon showed less seasonal variation in aggregate stability than soils with small amounts of organic carbon. This suggests that in less organic soils organic materials, mainly microbial in origin, play an important role in forming stable aggregates, though their effect is transient.
Errors in the estimation of soil water properties and their propagation through a hydrological model
Authors: Leenhardt D. 
Published: February 2007

Abstract. The Agricultural Catchments Research Unit model (ACRU) includes a decision support system (DSS) for estimating the water content of soil at field capacity (θfc) and wilting point (θwp) when these characteristics are not directly measurable. Three methods of estimation are proposed: (a) based on silt and clay content and bulk density, (b) based on clay content only, and (c) based on soil series. These three pedotransfer functions are compared with respect to both the estimation of θfc and θwp and the propagation of errors when the actual evapotranspiration of a wheat crop (E) is predicted over the growing season by the ACRU model.The standard error of estimation was between 0.066 and 0.082 m3/m3 for θfc, between 0.056 and 0.069 m3/m3 for θwp and between 29.9 and 34.8 mm of water for E. The method based on silt and clay contents and bulk density predicted θfc and θwp for non‐swelling soils most precisely. The method based on soil series was better than other methods for swelling soils. It also performed better for estimating available water capacity and consequently for predicting E from a conceptual soil water model. The propagated error of estimating θfc and θwp using the DSS reached 15–18% of the simulated E. The error in the prediction of E can reach 26–30% when spatial variation in soil properties is also estimated.
Spatial interpolation of soil hydraulic properties and simulated rice yield
Authors: Wopereis M.C.S. , Stein A. , Kropff M.J. , Bouma J. 
Published: February 2007

Abstract. Simulated estimates of crop yield were made for rainfed rice in a 50 ha dryland rice area. The aim was to investigate how soil units and management units of different sizes with different yields could be used to obtain values for areas of land. Two procedures were applied. First, yields were simulated at six sites, that were representative of six soil mapping units. Second, yields were simulated using soil information from 133 auger sites, and were interpolated over management units using block kriging. Differences between the two procedures for the total area and for a test set of 22 additionally sampled locations were small. A 60% increase in precision was achieved when relatively large management units were defined.A Geographical Information System was used to identify areas with greatest yield potential for rainfed dryland rice. Statistical analysis showed that the six soil units could be grouped into three yield classes. The largest yields were obtained for a sub‐area comprising 11% of the survey area which was associated with a slowly permeable Bg horizon in the soil profile.It was concluded that the best procedure for the spatial interpolation of simulated rice yield should be based on preliminary simulation of crop yields. A sensitivity analysis of the impact of weather variability and soil heterogeneity on the variation of yield was useful to detect the importance of their contributions. The procedures developed in this study are of value in obtaining a reliable estimate of average yield, and can consequently be used for associated cost‐benefit calculations.