bluuebunny/crossref_metadata_2025 huggingface dataset:
Visual Recognition of Biological Motion is Impaired in Children With Autism
Authors: Blake Randolph , Turner Lauren M. , Smoski Moria J. , Pozdol Stacie L. , Stone Wendy L.
Published: December 2004

Autistic children and typically developing control children were tested on two visual tasks, one involving grouping of small line elements into a global figure and the other involving perception of human activity portrayed in point-light animations. Performance of the two groups was equivalent on the figure task, but autistic children were significantly impaired on the biological motion task. This latter deficit may be related to the impaired social skills characteristic of autism, and we speculate that this deficit may implicate abnormalities in brain areas mediating perception of human movement.
Psychological Models of Professional Decision Making
Authors: Dhami Mandeep K.
Published: December 2004

People are often expected to make decisions based on all of the relevant information, weighted and combined appropriately. Under many conditions, however, people use heuristic strategies that depart from this ideal. I tested the ability of two models to predict bail decisions made by judges in two courts. In both courts, a simple heuristic proved to be a better predictor of judicial decisions than a more complex model that instantiated the principles of due process. Specifically, judges were “passing the buck” because they relied on decisions made by the police, prosecution, and previous bench. Problematically, these earlier decisions were not significantly related to case characteristics. These findings have implications for the types of models researchers use to capture professional decision-making policies.
Partition Priming in Judgment Under Uncertainty
Authors: Fox Craig R. , Rottenstreich Yuval
Published: December 2004

We show that likelihood judgments are biased toward an ignorance-prior probability that assigns equal credence to each mutually exclusive event considered by the judge. The value of the ignorance prior depends crucially on how the set of possibilities (i.e., the state space) is subjectively partitioned by the judge. For instance, asking “what is the probability that Sunday will be hotter than any other day next week?” facilitates a two-fold case partition, (Sunday hotter, Sunday not hotter), thus priming an ignorance prior of 1/2. In contrast, asking “what is the probability that the hottest day of the week will be Sunday?” facilitates a seven-fold class partition, (Sunday hottest, Monday hottest, etc.), priming an ignorance prior of 1/7. In four studies, we observed systematic partition dependence: Judgments made by participants presented with either case or class formulations of the same query were biased toward the corresponding ignorance prior.
Perceiving an Object and Its Context in Different Cultures
Authors: Kitayama Shinobu , Duffy Sean , Kawamura Tadashi , Larsen Jeff T.
Published: December 2004

In two studies, a newly devised test (framed-line test) was used to examine the hypothesis that individuals engaging in Asian cultures are more capable of incorporating contextual information and those engaging in North American cultures are more capable of ignoring contextual information. On each trial, participants were presented with a square frame, within which was printed a vertical line. Participants were then shown another square frame of the same or different size and asked to draw a line that was identical to the first line in either absolute length (absolute task) or proportion to the height of the surrounding frame (relative task). The results supported the hypothesis: Whereas Japanese were more accurate in the relative task, Americans were more accurate in the absolute task. Moreover, when engaging in another culture, individuals tended to show the cognitive characteristic common in the host culture.
IQ on the Rise
Authors: Daley Tamara C. , Whaley Shannon E. , Sigman Marian D. , Espinosa Michael P. , Neumann Charlotte
Published: December 2004

Multiple studies have documented significant IQ gains over time, a phenomenon labeled the Flynn effect. Data from 20 industrialized nations show massive IQ gains over time, most notably in culturally reduced tests like the Raven's Progressive Matrices. To our knowledge, however, this is the first study to document the Flynn effect in a rural area of a developing country. Data for this project were collected during two large studies in Embu, Kenya, in 1984 and 1998. Results strongly support a Flynn effect over this 14-year period, with the most significant gains found in Raven's matrices. Previously hypothesized explanations (e.g., improved nutrition; increased environmental complexity; and family, parental, school, and methodological factors) for the Flynn effect are evaluated for their relevance in this community, and other potential factors are reviewed. The hypotheses that resonate best with our findings are those related to parents' literacy, family structure, and children's nutrition and health.
Comparing the Sensitivity of Manual Pursuit and Perceptual Judgments to Pictorial Depth Effects
Authors: López-Moliner Joan , Smeets Jeroen B.J. , Brenner Eli
Published: December 2004

We examined whether a pictorial depth illusion influences the manual pursuit of a moving dot to the same extent that it influences the dot's apparent displacement. Fourteen subjects performed two tasks. In one case, they used their unseen hand to track a dot that moved on an elliptical path. In the other, they first watched the dot move on the same path, and then set an ellipse to match the shape of the dot's path. The illusion influenced the two tasks to the same extent, suggesting that the visual information processing is the same for the two tasks.
When Prejudice Does Not Pay
Authors: Richeson Jennifer A. , Shelton J. Nicole
Published: December 2004

This study examined the influence of interracial interaction on the cognitive functioning of members of a dominant racial group. White participants had a brief interaction with either a White or a Black confederate, and then completed an ostensibly unrelated Stroop color-naming test. Prior to the interaction, participants' racial attitudes regarding Whites and Blacks were measured via the Implicit Association Test. Racial attitudes were predictive of impairment on the Stroop test for individuals who participated in interracial interactions, but not for those who participated in same-race interactions. The results are consistent with recently proposed resource models of self-regulation and executive control in that interracial interaction, a particularly taxing exercise of self-regulation for highly prejudiced individuals, negatively affected performance on a subsequent, yet unrelated, test of executive function.
Learning to Recognize Objects
Authors: Smith Linda B.
Published: December 2004

A theory of object recognition requires a theory of shape. Despite considerable empirical and theoretical research, however, a definition of object shape has proved elusive. Two experiments provide new insights by showing that children's object recognition changes dramatically during the period between 17 and 25 months. During this time, children develop the ability to recognize stylized three-dimensional caricatures of known and novel objects. This ability is linked to the number of object names in children's vocabularies, suggesting that category learning may be a driving force behind the developmental changes.
The Role of Effort in Perceiving Distance
Authors: Proffitt Dennis R. , Stefanucci Jeanine , Banton Tom , Epstein William
Published: December 2004

Berkeley proposed that space is perceived in terms of effort. Consistent with his proposal, the present studies show that perceived egocentric distance increases when people are encumbered by wearing a heavy backpack or have completed a visual-motor adaptation that reduces the anticipated optic flow coinciding with walking effort. In accord with Berkeley's proposal and Gibson's theory of affordances, these studies show that the perception of spatial layout is influenced by locomotor effort.
Verifying Different-Modality Properties for Concepts Produces Switching Costs
Authors: Pecher Diane , Zeelenberg René , Barsalou Lawrence W.
Published: December 2004

According to perceptual symbol systems, sensorimotor simulations underlie the representation of concepts. It follows that sensorimotor phenomena should arise in conceptual processing. Previous studies have shown that switching from one modality to another during perceptual processing incurs a processing cost. If perceptual simulation underlies conceptual processing, then verifying the properties of concepts should exhibit a switching cost as well. For example, verifying a property in the auditory modality (e.g., BLENDER-loud) should be slower after verifying a property in a different modality (e.g., CRANBERRIES-tart) than after verifying a property in the same modality (e.g., LEAVES-rustling). Only words were presented to subjects, and there were no instructions to use imagery. Nevertheless, switching modalities incurred a cost, analogous to the cost of switching modalities in perception. A second experiment showed that this effect was not due to associative priming between properties in the same modality. These results support the hypothesis that perceptual simulation underlies conceptual processing.
Children's Reliance on Creator's Intent in Extending Names for Artifacts
Authors: Diesendruck Gil , Markson Lori , Bloom Paul
Published: December 2004

When children learn a name for a novel artifact, they tend to extend the name to other artifacts that share the same shape—a phenomenon known as the shape bias. The present studies investigated an intentional account of this bias. In Study 1, 3-year-olds were shown two objects of the same shape, and were given an explanation for why the objects were the same shape even though they were intended to be different kinds. The shape bias disappeared in children provided with this explanation. In Study 2, 3-year-olds were shown triads of objects, and were either given no information about the function of a named target object, told the function that object could fulfill, or told the functions all three objects were intended to fulfill. Only in the third condition did children overcome a shape bias in favor of a function bias when extending the name of the target object. These findings indicate that 3-year-olds' shape bias results from intuitions about what artifacts were intended to be.
Beyond social regulation? New instruments and/or a new agenda for social policy at Lisbon?
Authors: Wincott Daniel
Published: December 2004

The consistent failure to match EU market integration with social policies provoked the development of new modes of European governance for welfare provision in the early 1990s. Based on policy co‐ordination rather than integration, these new governance modes were consolidated as the ‘Open Method of Co‐ordination’ (OMC) at the Lisbon Summit in 2000. This article analyses the scope and limits of the OMC, locating it in the context of broader trends and tendencies in governance and social provision. Indeed, the perceived ‘success’ of the OMC may reflect a deeper trend in social policy across western Europe and beyond, towards ‘active’ welfare policies. In many ways the OMC is consistent with the influential ‘regulatory state’ vision of the EU. Yet by ‘activating’ welfare the OMC may challenge market liberal theories of European economic regulation. The first seeks to integrate economic and social policies while the latter is premised on their separation.
Estimation of Bivariate and Marginal Distributions with Censored Data
Authors: Akritas Michael G. , Keilegom Ingrid Van
Published: December 2004

Consider a pair of random variables, both subject to random right censoring. New estimators for the bivariate and marginal distributions of these variables are proposed. The estimators of the marginal distributions are not the marginals of the corresponding estimator of the bivariate distribution. Both estimators require estimation of the conditional distribution when the conditioning variable is subject to censoring. Such a method of estimation is proposed. The weak convergence of the estimators proposed is obtained. A small simulation study suggests that the estimators of the marginal and bivariate distributions perform well relatively to respectively the Kaplan–Meier estimator for the marginal distribution and the estimators of Pruitt and van der Laan for the bivariate distribution. The use of the estimators in practice is illustrated by the analysis of a data set.
Maximum Likelihood Estimation for the Proportional Hazards Model with Partly Interval-Censored Data
Authors: Kim Jong S.
Published: December 2004

The maximum likelihood estimator (MLE) for the proportional hazards model with partly interval-censored data is studied. Under appropriate regularity conditions, the MLEs of the regression parameter and the cumulative hazard function are shown to be consistent and asymptotically normal. Two methods to estimate the variance–covariance matrix of the MLE of the regression parameter are considered, based on a generalized missing information principle and on a generalized profile information procedure. Simulation studies show that both methods work well in terms of the bias and variance for samples of moderate size. An example illustrates the methods.
Inference for Clusters of Extreme Values
Authors: Ferro Christopher A. T. , Segers Johan
Published: December 2004

Inference for clusters of extreme values of a time series typically requires the identification of independent clusters of exceedances over a high threshold. The choice of declustering scheme often has a significant effect on estimates of cluster characteristics. We propose an automatic declustering scheme that is justified by an asymptotic result for the times between threshold exceedances. The scheme relies on the extremal index, which we show may be estimated before declustering, and supports a bootstrap procedure for assessing the variability of estimates.
Bayesian Clustering and Product Partition Models
Authors: Quintana Fernando A. , Iglesias Pilar L.
Published: December 2004

We present a decision theoretic formulation of product partition models (PPMs) that allows a formal treatment of different decision problems such as estimation or hypothesis testing and clustering methods simultaneously. A key observation in our construction is the fact that PPMs can be formulated in the context of model selection. The underlying partition structure in these models is closely related to that arising in connection with Dirichlet processes. This allows a straightforward adaptation of some computational strategies—originally devised for nonparametric Bayesian problems—to our framework. The resulting algorithms are more flexible than other competing alternatives that are used for problems involving PPMs. We propose an algorithm that yields Bayes estimates of the quantities of interest and the groups of experimental units. We explore the application of our methods to the detection of outliers in normal and Student t regression models, with clustering structure equivalent to that induced by a Dirichlet process prior. We also discuss the sensitivity of the results considering different prior distributions for the partitions.
National Borders, Trade and Migration
Authors: Helliwell John F.
Published: December 2004

The paper confirms a strikingly large effect of national borders on trade patterns. Estimates comparing trade among Canadian provinces with that between Canadian provinces and US states show interprovincial trade in 1988–90 to have been more than 20 times as dense as that between provinces and states, with some evidence of a downward trend since, owing to the post‐FTA growth in trade between Canada and the USA. Using approximate data for the volumes and distances of internal trade in OECD countries, the 1988–92 border effect for unrelated OECD countries is estimated to exceed 12. Estimates from a census‐based gravity model of interprovincial and international migration show a much higher border effect for migration than for trade, with interprovincial migration among the Anglophone provinces almost 100 times as dense as that from US states to Canadian provinces.
Gründungen an der Schnittstelle zwischen Wissenschaft und Wirtschaft – die Rolle der Hochschulen
Authors: Meyer-Krahmer Frieder , Kulicke Marianne
Published: December 2004

In national innovation systems, universities are not only essential elements of the research infrastructure, but also main players in the field of education and further education. Their specific role in the interplay between knowledge production and market implementation of knowledge via start-ups derives from this fact. This article takes as its theme the university environment which supports and stimulates the start-up processes. It also shows the progress achieved in the German university landscape in recent years on the path towards a culture of entrepreneurship in teaching and research. This is manifested, for example, in the number of start-up chairs, the development of networks to exploit the start-up potential of universities together with regional partners, and in the numbers of spinoffs established.
Arbeitsmarktpolitik in der Europäischen Währungsunion
Authors: Berthold Norbert , Fehn Rainer
Published: December 2004

While policymakers in Europe were busy implementing EMU during the past decade, persistently high unemployment, which should have been the main policy issue from a normative point of view, was essentially left untackled in most continental European countries. This poses the urgent question of which approach labor market policy should now take in fighting unemployment and which changes have come about with EMU. To deal with this question, the article proceeds in three steps. It is first shown that a web of institutions in labor, goods and capital markets, which are different from those Anglo-Saxon countries and which are interconnected by politico-economic forces, is to blame for the dismal situation on most continental European labor markets. Secondly, it is argued that EMU is not likely to boost employment growth automatically. Thirdly, it is outlined which are the key policy measures to alleviate unemployment in continental Europe and it is discussed whether EMU makes the actual implementation of these measures more likely.
Politics and the nation: nationalist mobilisation of ethnic differences
Authors: Máiz Ramón
Published: December 2004

Abstract. Based on a critique of the exogenous and expressive views of politics underlying many studies of nationalism, this article analyses the political factors that affect nation‐building processes in a direct manner. First, ethnicity should be considered not so much as an historical and objective starting point but as the outcome of nationalist intellectuals' efforts at filtering and selecting political and cultural elements. It is important to examine the structure and genealogy of nationalist ideological capital using myth/symbol analysis or frame analysis. Second, one of the key concepts in the study of nationalist movements is the Political Opportunity Structure, as it refers to the developmental context, both institutional (democratisation, decentralisation, etc.) and strategic (potential allies, electoral dealignments, etc.). In this sense, ethnic regulation policies should not be taken as mere effects or responses, but as decisive intervening causes in the very process of national identity‐building. Finally, this article argues that rational choice analysis and collective action logic can be found useful in explaining the successes or failures of nationalist movements that attempt to mobilise and organise politically as mass phenomena.
Target‐to‐target interval versus probability effects on P300 in one‐ and two‐tone tasks
Authors: Croft R. J. , Gonsalvez C. J. , Gabriel C. , Barry R. J.
Published: December 2004

The P3(00) is an electrophysiological index of neural processing that varies with such stimulus parameters as interstimulus interval (ISI) and target probability, with a common view being that it reflects an endogenous form of memory update. Building on previous research, we argue that relations between P3 amplitude and both ISI and probability may be attributable to the target‐to‐target interval (TTI). Employing between‐subject (Experiment 1; N=24) and within‐subject (Experiment 2; N=10) designs, the present paper addresses this by testing subjects on a standard two‐tone auditory oddball task as well as a one‐tone task. In both studies, P3 amplitude increased and latency decreased linearly with TTI, and these relations were relatively unaffected by ISI or probability. This suggests that ISI and probability per se do not independently affect P3 amplitude, and that TTI offers a strong explanation of the reported relations between P3 amplitude and both ISI and probability.
Electrophysiological correlates of anticipatory and poststimulus components of task switching
Authors: Karayanidis Frini , Coltheart Max , Michie Patricia T. , Murphy Karen
Published: December 2004

Task‐switching paradigms can shed light on cognitive and neural processes underlying attentional control mechanisms. An alternating runs task‐switching paradigm (R. D. Rogers & S. Monsell, 1995) is used to identify ERP components associated with anticipatory and poststimulus components of task‐switching processes. Subjects alternated between two tasks in a predictable series (AABB). Reaction time (RT) switch cost reduced with increasing response‐stimulus (R‐S) interval and a residual switch cost remained at the longest R‐S interval. A switch‐related positivity (D‐Pos) developed in the R‐S interval. D‐Pos was time‐locked to response onset, peaked around 400 ms post‐response onset, and was unaffected by task‐set interference. A switch‐related negativity (D‐Neg) emerged after stimulus onset. D‐Neg peaked earlier with increasing R‐S interval and its amplitude and latency were affected by task‐set interference. D‐Pos and D‐Neg were interpreted within current models of task‐switching.
An ERP study of change detection, change blindness, and visual awareness
Authors: Koivisto Mika , Revonsuo Antti
Published: December 2004

Electrophysiological correlates of change detection and change blindness were studied in 12 observers. The ERP difference between detected changes and undetected changes was considered an electrophysiological correlate of visual awareness. Two distinct electrophysiological responses correlated with the awareness of change. First, awareness was associated with a negative amplitude shift at posterior sites around 200 ms after the change in the stimulus. The latency of the negative shift varied as a function of the task difficulty and the speed of becoming aware of the change. Second, ERPs to detected changes became more positive as compared with undetected changes around 400 ms after the change in the stimulus, peaking at parietal sites. We suggest that the earlier negativity is associated with a change in the content of visual awareness, whereas the later positivity may reflect more global processes needed in decision making and action planning.
MMN and attention: Competition for deviance detection
Authors: Sussman Elyse , Winkler István , Wang Wenjung
Published: December 2004

We addressed the question of whether the mismatch negativity (MMN) event‐related potential reflects an attention‐independent process. Previous studies have shown that the MMN response to intensity deviation was significantly reduced or even abolished when attention was highly focused on a concurrent sound channel, whereas no conclusive evidence of attentional sensitivity has been obtained for frequency deviation. We tested a new hypothesis suggesting that competition between detection of identical deviations in attended and unattended channels and the biasing of this competition induced by the subject's task account for the observed MMN effects. In a fast‐paced dichotic paradigm, we set up competition for frequency MMN and removed it for intensity MMN. We found that frequency MMN was now abolished in the unattended channel, whereas the amplitude of the intensity MMN was unaffected. These results support the competition hypothesis and suggest that selective attention in and of itself does not affect the MMN. Top‐down processes can determine what information reaches the deviance‐detection process when changes in multiple channels vie for the same MMN resource and one of the competing changes is relevant for the subject's task.
The music of speech: Music training facilitates pitch processing in both music and language
Authors: Schön Daniele , Magne Cyrille , Besson Mireille
Published: December 2004

The main aim of the present experiment was to determine whether extensive musical training facilitates pitch contour processing not only in music but also in language. We used a parametric manipulation of final notes' or words' fundamental frequency (F0), and we recorded behavioral and electrophysiological data to examine the precise time course of pitch processing. We compared professional musicians and nonmusicians. Results revealed that within both domains, musicians detected weak F0 manipulations better than nonmusicians. Moreover, F0 manipulations within both music and language elicited similar variations in brain electrical potentials, with overall shorter onset latency for musicians than for nonmusicians. Finally, the scalp distribution of an early negativity in the linguistic task varied with musical expertise, being largest over temporal sites bilaterally for musicians and largest centrally and over left temporal sites for nonmusicians. These results are taken as evidence that extensive musical training influences the perception of pitch contour in spoken language.
Heart period variability of trained and untrained men at rest and during mental challenge
Authors: Boutcher Stephen H. , Nugent F. W. , McLaren Peter F. , Weltman Arthur L.
Published: December 2004

The effect of aerobic training on parasympathetic reactivity to mental stress is unclear. Thus, the parasympathetic response, as assessed by time series analysis of heart period variability (HPVts), of 10 trained male runners (trained group), 10 inherently low resting heart rate untrained men (low HR group), and 10 normal resting HR men (control group) at rest and to two mental stressors was examined. Participants completed a mental arithmetic and Stroop task. Resting HPVts at high and medium frequencies was significantly greater for the trained and the low HR groups than for the control group. Significantly greater decreases in HPVts at the medium frequency during arithmetic recovery were measured for the trained and low HR groups compared with the response of the control group. Significantly greater decreases in HPVts at both the the high and medium frequencies during the first two epochs of the Stroop occurred only for the trained and low HR groups. These results suggest that the greater HPVts at rest and decline in HPVts during and after mental challenge is influenced by both aerobic training and genetic inheritance.
Hemodynamics during rest and behavioral stress in normotensive men at high risk for hypertension
Authors: Lovallo William R. , Al'absi Mustafa
Published: December 2004

Persons at risk for hypertension may show elevated blood pressure (BP) at rest and during mental stress; however, the hemodynamics underlying the BP of those persons at high risk are not well characterized. We chose 21 high risk and 21 low risk men using their parental hypertension history and resting systolic blood pressures on two screenings. Then, on a day of extended rest versus a day with prolonged mental arithmetic and reaction time tasks, we examined whether high risk BP elevations reflected greater vascular resistance or cardiac output. High risk men had raised systolic/diastolic pressures (Fs = 74/15, ps < .0001/.0001) and higher vascular resistance (F= 6.6, p < .02) with minimal differences in heart rate and cardiac output. This finding implicates vascular resistance as the altered element in BP control in these high risk men tested in a familiar environment with minimal task‐related threat.
Brain ERPs of depressed patients to complex tones in an oddball task: Relation of reduced P3 asymmetry to physical anhedonia
Authors: Bruder Gerard E. , Tenke Craig E. , Towey James P. , Leite Paul , Fong Regan , Stewart Jonathan E. , McGrath Patrick J. , Quitkin Frederic M.
Published: December 2004

Event‐related potentials to binaural complex tones were recorded from 40 depressed outpatients and 22 normal control participants at 30 electrode sites. Patients did not differ from control participants in N1 or P3 amplitude but showed greater N2. N2 was greater over right than over the left hemisphere at lateral sites in patients and control participants. A P3 asymmetry was found for control participants and patients with low scores on a physical anhedonia scale, but not for patients with high anhedonia scores. Topographic (local Laplacian) maps corresponding to P3 showed greater radial current flow over right than over left central regions in control participants. Patients with high anhedonia did not show this asymmetry, whereas patients with low anhedonia showed an intermediate asymmetry. These findings support the hypothesis that anhedonic depression is associated with dysfunction of right hemisphere mechanisms mediating the processing of complex pitch information.
ECG artifacts and heart period variability: Don't miss a beat!
Authors: Berntson Gary G. , Stowell Jeffrey R.
Published: December 2004

The impact of artifacts on estimates of heart period variability were evaluated by modeling the effects of missed R‐waves and spurious R‐wave detections in actual and simulated heart period series. Results revealed that even a single artifact, occurring within a 128‐s interbeat interval series, can impart substantial spurious variance into all commonly analyzed frequency bands, including that associated with respiratory sinus arrhythmia. In fact, the spurious variance introduced by a single artifact may be greater than that associated with true basal heart period variability and can far exceed typical effect sizes in psychophysiological studies. The effects of artifacts are not related to a specific analytical method and are apparent in both frequency and time domain analyses. Results emphasize the importance of artifact detection and resolution for studies of heart period variability.
Processing of novel sounds and frequency changes in the human auditory cortex: Magnetoencephalographic recordings
Authors: Alho Kimmo , Winkler István , Escera Carles , Huotilainen Minna , Virtanen Juha , Jääskeläinen Iiro P. , Pekkonen Eero , Ilmoniemi Risto J.
Published: December 2004

Whole‐head magnetoencephalographic (MEG) responses to repeating standard tones and to infrequent slightly higher deviant tones and complex novel sounds were recorded together with event‐related brain potentials (ERPs). Deviant tones and novel sounds elicited the mismatch negativity (MMN) component of the ERP and its MEG counterpart (MMNm) both when the auditory stimuli were attended to and when they were ignored. MMNm generators were located bilateral to the superior planes of the temporal lobes where preattentive auditory discrimination appears to occur. A subsequent positive P3a component was elicited by deviant tones and with a larger amplitude by novel sounds even when the sounds were to be ignored. Source localization for the MEG counterpart of P3a (P3am) suggested that the auditory cortex in the superior temporal plane is involved in the neural network of involuntary attention switching to changes in the acoustic environment.
Extinction in fear conditioning: Effects on startle modulation and evaluative self‐reports
Authors: Vansteenwegen Debora , Crombez Geert , Baeyens Frank , Eelen Paul
Published: December 2004

A basic feature of human evaluative conditioning is that the reported acquired valence of a previously neutral conditioned stimulus (CS) that has been paired with a valenced unconditioned stimulus (US), is resistant to extinction. The present study investigated whether startle modulation, sometimes presented as an index of acquired valence, reflected this basic feature. In a differential fear conditioning paradigm (n= 38) with an electrocutaneous stimulus as the US, a strong extinction manipulation was conducted by removing the US‐electrodes and by extended extinction trials. At the end of extinction, the results corroborated previous findings of evaluative conditioning in that the reported valence for CS+ was still more negative than for CS−, despite disappearance of the differential skin conductance responses. However, startle modulation did not show resistance‐to‐extinction. Results were discussed in terms of recent conceptualizations of extinction.
Contingent negative variation and cognitive performance in hypotension
Authors: Costa Marco , Stegagno Luciano , Schandry Rainer , Bitti Pio Enrico Ricci
Published: December 2004

The difference in attention and cognitive performance between 26 hypotensive (systolic blood pressure < 100 mmHg and diastolic blood pressure < 60 mmHg) and 22 normotensive female university students was assessed. Attention was examined with contingent negative variation (CNV) recorded using light and tone as S1 and S2. Cognitive performance was assessed by free recall of a list of words and two German tests of cognitive speed performance and sustained attention: Zahlen‐Verbindungs‐Test and d2. The hypotensive participants demonstrated a lower increase in negativity on the CNV. Moreover, in the free recall test, hypotensive individuals remembered fewer words, in comparison with normotensive subjects. Scores for hypotensive individuals on the Zahlen‐Verbindungs‐Test and d2 were also lower. No difference was found in reaction times to imperative stimuli (S2).
Speeded responses to audiovisual signal changes result from bimodal integration
Authors: Schröger Erich , Widmann Andreas
Published: December 2004

Integration of auditory and visual information was studied in humans detecting targets (i.e., location changes of the auditory, the visual, or both parts of a repetitively presented audiovisual stimulus). Behavioral results suggest that the time advantage to bimodal compared with unimodal targets was due to combined rather than separate processing of the auditory and the visual target information. Event‐related brain potential results revealed strong audiovisual interactions supporting interactive and not independent coactivation models. The time course of this interaction suggests that the audiovisual integration occurred after low‐level, sensory processing but well before the execution of the motor response.
Event‐related potentials to structural familiar face incongruity processing
Authors: Jemel Boutheina , George Nathalie , Olivares Ela , Fiori Nicole , Renault Bernard
Published: December 2004

Thirty scalp sites were used to investigate the specific topography of the event‐related potentials (ERPs) related to face associative priming when masked eyes of familiar faces were completed with either the proper features or incongruent ones. The enhanced negativity of N210 and N350, due to structural incongruity of faces, have a “category specific” inferotemporal localization on the scalp. Additional analyses support the existence of multiple ERP features within the temporal interval typically associated with N400 (N350 and N380), involving occipitotemporal and centroparietal areas. Seven reliable dipole locations have been evidenced using the brain electrical source analysis algorithm. Some of these localizations (fusiform, parahippocampal) are already known to be involved in face recognition, the other ones being related to general cognitive processes related to the task's demand. Because of their specific topography, the observed effects suggest that the face structural congruency process might involve early specialized neocortical areas in parallel with cortical memory circuits in the integration of perceptual and cognitive face processing.
Effects of stimulus intensity, risetime, and duration on autonomic and behavioral responding: Implications for the differentiation of orienting, startle, and defense responses
Authors: Turpin Graham , Schaefer Florian , Boucsein Wolfram
Published: December 2004

The effects of stimulus intensity, duration, and risetime on the autonomic and behavioral components of orienting, startle, and defense responses were investigated. Six groups of 10 students were presented with 15 white noise stimuli at either 60 or 100 dB, with controlled risetimes of either 5 or 200 ms, and at stimulus durations of 1 or 5 s (1 s only in the case of the 60‐dB groups). A dishabituation stimulus consisting of a 1000 Hz tone was also presented. Measures consisted of skin conductance and heart rate, together with ratings of facial expressions and upper torso movement obtained using video recording. Increased intensity resulted in greater amplitudes and frequencies of electrodermal and behavioral responses, and a change from cardiac deceleration to acceleration. Faster risetimes elicited larger electrodermal responses, greater frequencies of eye‐blinks, head and body movements, and larger cardiac accelerations. The effects of duration for the 100‐dB stimuli were less clear‐cut. Overall, the results are discussed in relation to the differentiation of orienting, startle, and defense responses.
Emotion processing in three systems: The medium and the message
Authors: Simons Robert F. , Detenber Benjamin H. , Roedema Thomas M. , Reiss Jason E.
Published: December 2004

In the context of picture viewing, consistent and specific relationships have been found between two emotion dimensions (valence and arousal) and self‐report, physiological and overt behavioral responses. Relationships between stimulus content and the emotion‐response profile can also be modulated by the formal properties of stimulus presentation such as screen size. The present experiment explored the impact of another presentation attribute, stimulus motion, on the perceived quality of the induced emotion and on its associated physiological response pattern. Using a within‐subject design, moving and still versions of emotion‐eliciting stimuli were shown to 35 subjects while facial muscle, heart rate, skin conductance, and emotion self‐reports were monitored. The impact of motion was dramatic. Self‐report and physiological data suggested strongly that motion increased arousal, had little impact on valence, and captured and sustained the subject's attention to the image.
Schizophrenia: The broken P300 and beyond
Authors: Ford Judith M.
Published: December 2004

Many of the social, economic, and political problems facing people with schizophrenia are due to a misconception in the community that schizophrenia is not a biologically based disease but a myth. Because the diagnosis is based on self‐reported symptoms, it is difficult for many people to acknowledge that schizophrenia is real. One goal of psychophysiological research has been to anchor both diagnosis and symptoms in biological reality. Reduction of the amplitude of the P300 component of the event‐related potential (ERP) is the most replicable biological marker of the disease. Data are presented suggesting that P300 is both a state and a trait marker of the disease and may be sensitive to the progressive/degenerative course of the disease. Although the P300 tracks changes in clinical symptoms, it remains reduced even in patients in relative remission. P300 amplitude reduction is related to enduring negative symptoms, waning of attention, and gray matter volume deficits. ERP components other than P300 can also manifest the biological reality of various symptoms of the disease.
The effects of threat and nonthreat word lead stimuli on blink modification
Authors: Aitken Christopher J. , Siddle David A. T. , Lipp Ottmar V.
Published: December 2004

Two experiments examined the effects of visually presented threat and nonthreat word lead stimuli on blink modification among unselected young adults (Experiment 1, N= 35) and participants selected for low and high trait anxiety (Experiment 2, N= 60). The blink reflex was elicited by a white noise probe of 105 dB. Lead stimulus intervals of 60, 120, 240, and 2000 ms were used in both experiments. Prepulse inhibition was observed at the 240‐ms interval and prepulse facilitation was observed at the 60‐ms interval in both experiments. Also, greater facilitation was found in both experiments during threat words at the 60‐ms interval and greater inhibition during threat words at the 240‐ms interval. Experiment 2 provided some evidence that the greater facilitation during threat words than during nonthreat words at the 60‐ms probe interval may be found in high trait anxious participants, but not in low trait anxious participants. The results are discussed in relation to contemporary information processing theories of anxiety.
Semantic and affective processing in psychopaths: An event‐related potential (ERP) study
Authors: Kiehl Kent A. , Hare Robert D. , McDonald John J. , Brink Johann
Published: December 2004

We tested the hypothesis that psychopathy is associated with abnormal processing of semantic and affective verbal information. In Task 1, a lexical decision task, and in Task 2, a word identification task, participants responded faster to concrete than to abstract words. In Task 2, psychopaths made more errors identifying abstract words than concrete words. In Task 3, a word identification task, participants responded faster to positive than to negative words. In all three tasks, nonpsychopaths showed the expected event‐related potential (ERP) differentiation between word stimuli, whereas psychopaths did not. In each task, the ERPs of the psychopaths included a large centrofrontal negative‐going wave (N350); this wave was absent or very small in the nonpsychopaths. The interpretation and significance of these differences are discussed.
From print to meaning: An electrophysiological investigation of the role of phonology in accessing word meaning
Authors: Ziegler Johannes C. , Benraïss Abdelrhani , Besson Mireille
Published: December 2004

This study investigated the role and time‐course of phonology in accessing meaning during silent reading. In Experiment 1, the homophone effect was replicated in a semantic categorization task in French. When deciding whether a stimulus belonged to a semantic category (FOOD), subjects made more errors to homophones (MEET) than to orthographic controls (MELT). In Experiment 2, event‐related brain potentials (ERPs) were used to study the online development of this effect. If access to meaning was mediated by phonology, smaller N400 components should be obtained to homophones than to orthographic controls. The ERP data exhibited a full‐blown N400 component to homophones that did not differ from the N400 to controls. No differences between homophones and controls were found before the N400. After the N400, however, homophones differed from controls, with ERPs to homophones being similar to those of correct category exemplars. The results suggest that the final selection of a word's meaning does not depend on its phonological form. This result is incompatible with a strong phonological view according to which the only way to meaning is via a word's phonology.
Scaling is necessary when making comparisons between shapes of event‐related potential topographies: A reply to Haig et al.
Authors: Ruchkin Daniel S. , Johnson Ray , Friedman David
Published: December 2004

A. R. Haig, E. Gordon, and S. Hook (1997) disputed G. McCarthy and C. C. Wood's (1985) contention that scaling should be used when assessing the statistical significance of between condition (or group) differences in the shapes of event‐related potential (ERP) scalp topographies. Haig et al. based their contention upon the lack of empirical realism in McCarthy and Wood's model of within‐group ERP noise, claiming that McCarthy and Wood's results could not be generalized to realistic ERP data. We argue, on both empirical and theoretical grounds, that Haig et al. do not make a compelling case against generalization of McCarthy and Wood's results. Moreover, Haig et al.'s conclusion is based upon a misconception of how scaling should be used. We conclude that when a quantitative measure of differences between topographic shapes is needed, scaling is not an option—it is a requirement.
Affective reactions to acoustic stimuli
Authors: Bradley Margaret M. , Lang Peter J.
Published: December 2004

Emotional reactions to naturally occurring sounds (e.g., screams, erotica, bombs, etc.) were investigated in two studies. In Experiment 1, subjects rated the pleasure and arousal elicited when listening to each of 60 sounds, followed by an incidental free recall task. The shape of the two‐dimensional affective space defined by the mean ratings for each sound was similar to that previously obtained for pictures, and, like memory for pictures, free recall was highest for emotionally arousing stimuli. In Experiment 2, autonomic and facial electromyographic (EMG) activity were recorded while a new group of subjects listened to the same set of sounds; the startle reflex was measured using visual probes. Listening to unpleasant sounds resulted in larger startle reflexes, more corrugator EMG activity, and larger heart rate deceleration compared with listening to pleasant sounds. Electrodermal reactions were larger for emotionally arousing than for neutral materials. Taken together, the data suggest that acoustic cues activate the appetitive and defensive motivational circuits underlying emotional expression in ways similar to pictures.
Discrete and continuous prepulses have differential effects on startle prepulse inhibition and skin conductance orienting
Authors: Wynn Jonathan K. , Dawson Michael E. , Schell Anne M.
Published: December 2004

The effectiveness of different types of auditory prepulses in eliciting skin conductance orienting and in producing prepulse inhibition (PPI) of the acoustic startle eyeblink was studied in two experiments. A discrete white noise prepulse produced greater PPI than either a continuous white noise, a discrete tone, or a continuous tone. The discrete white noise advantage was not due to similarity in bandwidth to the startle pulse or to a refractory effect of the prepulse. Moreover, a dissociation between PPI and skin conductance orienting was seen in both experiments. PPI using auditory prepulses appears to be dependent primarily on the acoustic characteristics of the transient portion of the prepulse, whereas skin conductance orienting is more dependent on the sustained portions of the stimulus.
The relationship of respiratory sinus arrhythmia to the co‐activation of autonomic and facial responses during the Rorschach test
Authors: Kettunen Joni , Ravaja Niklas , Näätänen Petri , Keltikangas‐Järvinen Liisa
Published: December 2004

We studied the relationship of respiratory sinus arrhythmia (RSA) to the co‐activation of autonomic and facial expressive responses in 37 adult men during Rorschach testing. Interbeat interval (IBI), electrodermal activity, and facial electromyography were recorded continuously during the experiment. Prevailing mood and variability in the experience of valence and arousal were also measured. Bivariate intraindividual time series analysis was used to quantify spontaneously coupled phasic physiological responses. The results suggested that (a) spontaneous autonomic and expressive responses tend to parallel in time; (b) baseline, task‐level, and task‐induced change of RSA were positively related to coupled autonomic–expressive responses, a change in mood toward a more energetic state, and a tendency to have more variability in the emotional experience during the task; and (c) especially cardiac–expressive response coupling was related to mood change. It is concluded that the vagal system is related to the control of facial muscle activity and may mediate both tonic and phasic emotion‐related changes in IBI. The role of phasic intraindividual response patterns in emotional and social behavior is highlighted.