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Attentional Processing (attentional + processing)
Selected AbstractsNeurocognitive variation in smoking behavior and withdrawal: genetic and affective moderatorsGENES, BRAIN AND BEHAVIOR, Issue 1 2009D. E. Evans A burgeoning literature suggests that attentional factors are associated with smoking behavior (e.g. direct nicotine effects and smoking withdrawal). This study examined differences in attentional processing between nonsmokers, satiated smokers and overnight nicotine-deprived smokers by comparing the amplitude of the P300 (P3) component of the event-related brain potential (ERP) elicited during a go,nogo task. We also examined the moderating effects of a common dopamine receptor genotype and state negative affect (SNA) on this ERP index of attention. Nonsmokers relative to smokers had greater nogo P3 amplitude. Carrying the A1 allele at the dopamine receptor D2 (DRD2) Taq1A polymorphism site moderated the effects of withdrawal on nogo P3 amplitude, suggesting the A1 allele is a vulnerability marker for withdrawal-related attentional deficits. Increased SNA also predicted attenuated P3 amplitude among deprived smokers. These findings suggest that DRD2 status and SNA moderate the effects of smoking status and withdrawal on neurocognitive variation during attentional processing. This research contributes to a better understanding of the role of individual differences and attentional processing in smoking behavior. [source] Spatiotemporal mapping of sex differences during attentional processingHUMAN BRAIN MAPPING, Issue 9 2009Andres H. Neuhaus Abstract Functional neuroimaging studies have increasingly aimed at approximating neural substrates of human cognitive sex differences elicited by visuospatial challenge. It has been suggested that females and males use different behaviorally relevant neurocognitive strategies. In females, greater right prefrontal cortex activation has been found in several studies. The spatiotemporal dynamics of neural events associated with these sex differences is still unclear. We studied 22 female and 22 male participants matched for age, education, and nicotine with 29-channel-electroencephalogram recorded under a visual selective attention paradigm, the Attention Network Test. Visual event-related potentials (ERP) were topographically analyzed and neuroelectric sources were estimated. In absence of behavioral differences, ERP analysis revealed a novel frontal-occipital second peak of visual N100 that was significantly increased in females relative to males. Further, in females exclusively, a corresponding central ERP component at around 220 ms was found; here, a strong correlation between stimulus salience and sex difference of the central ERP component amplitude was observed. Subsequent source analysis revealed increased cortical current densities in right rostral prefrontal (BA 10) and occipital cortex (BA 19) in female subjects. This is the first study to report on a tripartite association between sex differences in ERPs, visual stimulus salience, and right prefrontal cortex activation during attentional processing. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] Attentional dysfunction of chronic schizophrenia: No association with long-term institutionalizationPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2002LUIGI CREMASCO MD Abstract Attentional processes play a central role in information selection, which is impaired in schizophrenic patients. In the present study, we attempted to characterize the attentional performance of chronic schizophrenics using a computerized assessment of the multiple components of attentional function. Two comparable samples, consisting, respectively, of out-patients and in-patients, were tested in order to assess the effect of chronic institutionalization. Twenty-four subjects (half in-patients and half out-patients) fulfillling DSM-IV criteria for schizophrenia were examined with a standard computerized battery for the assessment of attention, namely Testbatterie zur Aufmerksamkeitsprufung (TAP). Both groups were impaired on all measures of attentional processing (in terms of both reaction times and number of errors). There were no significant differences in attentional performance between in- and out-patients. In conclusion, the present findings confirm the presence of pervasive attentional dysfunction in chronic schizophrenia; the lack of significant differences in performance between in- and out-patients supports the hypothesis that the cognitive deficits are inherently associated with the illness and cannot be attributed to environmental/social factors. [source] The effects of smoking on selective attention as measured by startle reflex, skin conductance, and heart rate responses to auditory startle stimuliPSYCHOPHYSIOLOGY, Issue 1 2010Justin E. Greenstein Abstract The present study examined the effects of cigarette smoking on attentional processing by measuring nondeprived smokers' (n=39), minimally deprived smokers' (n=36), and nonsmokers' (n=34) startle eyeblink reflex, heart rate, and skin conductance responses (SCR) to acoustic startle stimuli (105 dB) during directed attention tasks. Whereas smokers demonstrated smaller startle responses than nonsmokers during a directed attention visual task, no difference in startle response magnitude emerged between the two smoking groups, nor did we observe an effect of smoking on SCR or heart rate response to the startle stimuli. Our findings suggest that smokers differ from nonsmokers in their selective attention abilities and that smoking does not enhance minimally deprived smokers' selective attention. [source] Probing attentional dysfunctions in schizophrenia: Startle modification during a continuous performance testPSYCHOPHYSIOLOGY, Issue 4 2008Erin A. Hazlett Abstract Startle eyeblink modification was measured in 20 relatively asymptomatic medicated schizophrenia outpatients and 18 matched controls in order to test for deficits in early and later stages of attentional processing during a memory-load version of the Continuous Performance Test. Participants viewed a series of digits and pressed a button after the digit 7 of each 3,7 sequence. On some trials, a startling noise burst was presented either 120 or 1200 ms following cues that a response might be needed soon (the digit 3) and also following noncues. Controls showed greater startle inhibition at 120 ms following cue than noncue prepulses, whereas patients showed equal inhibition to both, suggesting a deficiency in allocation of controlled attentional resources in early stages of processing. The patients, however, did show large startle inhibition at 120 ms when a distracting stimulus accompanied the task-relevant cue, unlike the controls, who ignored the distracting stimulus. In contrast, both groups showed equal startle inhibition 1200 ms following cue and noncue prepulses, indicating that later modality-specific attention processes are not impaired in patients during this paradigm. Both groups also showed equal inhibition at 120 ms during passively attended prepulses, suggesting that automatic attentional processes were not impaired in these patients. [source] Event-related potentials associated with sound discrimination versus novelty detection in childrenPSYCHOPHYSIOLOGY, Issue 1 2004eponien Abstract In children, deviant sounds in an oddball paradigm elicit a mismatch negativity (MMN) indexing discrimination of sound change and late difference negativity (LDN) with unknown functional significance. Salient sounds elicit an ERP index if orienting, P3a, and a late negative component, Nc. We compared children's responses elicited by moderate sound changes and novel sounds to examine the relationships between MMN and LDN, and LDN and Nc. Two components of the Nc, the Nc1 and Nc2, were identified. The scalp topography of LDN differed from those of the MMN and Nc1. Children's early P3a appeared mature but late P3a lacked frontal predominance. The findings suggested that LDN is not linked with either the sensory or attentional processing. It might reflect cognitive, albeit preattentive, processing of sound change. The Nc1 appears to reflect cognitive attentive processing of salient stimuli and the Nc2 might reflect reorienting after distraction. [source] Bias in attending to emotional facial expressions: Anxiety and visual search efficiencyAPPLIED COGNITIVE PSYCHOLOGY, Issue 3 2010Eriko Matsumoto There has been much controversy around the relationship between anxiety and attentional processing of threat-related information. The purpose of this study was to examine how threatening facial expressions affect attentional processing, according to the level of trait anxiety. Through visual search tasks, two different components of attentional bias to threat were investigated: engagement and disengagement of attention from an angry face. Two main results were found. First, reaction times (RTs) were slower in detecting the absence of a discrepant face in the all angry-display conditions rather than other expression conditions; however, there was no difference between anxiety groups. Second, the difference in search efficiency for the angry versus happy target was significant within the high-anxiety group but not within the low-anxiety group. The results suggest that the detection process for angry faces is more efficient for highly anxious people. On the other hand, the time to disengage attention from angry faces was not associated with anxiety level. Copyright © 2010 John Wiley & Sons, Ltd. [source] Impairment in attentional processing in a field survival environmentAPPLIED COGNITIVE PSYCHOLOGY, Issue 5 2008John Leach The suggestion that maladaptive behaviour often observed in survival incidents may be due to a restriction in attentional processing was tested using sub-components of the Test of Everyday Attention in participants undergoing a field survival exercise. Compared to a baseline condition and control group those undergoing environmental duress showed significant impairment in selective and sustained attention which taken together suggests dysfunction in controlled attention. No impairment was found in either attentional switching or auditory-verbal working memory. It is argued that this type of cognitive impairment makes flexible interaction with the survival environment difficult and the victim's behaviour becomes dominated by environmental cues at the expense of wilful, goal-directed survival behaviour. This would begin to answer at least one anomaly that exists in survivorship: why so many people perish when there is no need. Copyright © 2007 John Wiley & Sons, Ltd. [source] | |||||||||||||