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Selective Attention (selective + attention)
Selected AbstractsSelective attention in anxiety: Distraction and enhancement in visual searchDEPRESSION AND ANXIETY, Issue 1 2003Mike Rinck Abstract According to cognitive models of anxiety, anxiety patients exhibit an attentional bias towards threat, manifested as greater distractibility by threat stimuli and enhanced detection of them. Both phenomena were studied in two experiments, using a modified visual search task, in which participants were asked to find single target words (GAD-related, speech-related, neutral, or positive) hidden in matrices made up of distractor words (also GAD-related, speech-related, neutral, or positive). Generalized anxiety disorder (GAD) patients, social phobia (SP) patients afraid of giving speeches, and healthy controls participated in the visual search task. GAD patients were slowed by GAD-related distractor words but did not show statistically reliable evidence of enhanced detection of GAD-related target words. SP patients showed neither distraction nor enhancement effects. These results extend previous findings of attentional biases observed with other experimental paradigms. Depression and Anxiety 18:18,28, 2003. © 2003 Wiley-Liss, Inc. [source] Attention-like processes underlying optomotor performance in a Drosophila choice mazeDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2007Bruno van Swinderen Abstract The authors present a novel paradigm for studying visual responses in Drosophila. An eight-level choice maze was found to reliably segregate fly populations according to their responses to moving stripes displayed on a computer screen. Visual responsiveness was robust in wild-type flies, and performance depended on salience effects such as stimulus color and speed. Analysis of individual fly choices in the maze revealed that stereotypy, or choice persistence, contributed significantly to a strain's performance. On the basis of these observations, the authors bred wild-type flies for divergent visual phenotypes by selecting individual flies displaying extreme stereotypy. Selected flies alternated less often in the sequential choice maze than unselected flies, showing that stereotypy could evolve across generations. The authors found that selection for increased stereotypy impaired flies' responsiveness to competing stimuli in tests for attention-like behavior in the maze. Visual selective attention was further investigated by electrophysiology, and it was found that increased stereotypy also impaired responsiveness to competing stimuli at the level of brain activity. Combined results present a comprehensive approach to studying visual responses in Drosophila, and show that behavioral performance involves attention-like processes that are variable among individuals and thus sensitive to artificial selection. © 2006 Wiley Periodicals, Inc. Develop Neurobiol 67: 129,145, 2007. [source] The dynamics of development and evolution: Insights from behavioral embryologyDEVELOPMENTAL PSYCHOBIOLOGY, Issue 8 2007Robert Lickliter Abstract The perspective that features of species-typical behavior could be traced to experience that occurred prenatally was raised by Zing-Yang Kuo [1921 Journal of Philosophy 18: 645,664] early in the last century and Gilbert Gottlieb subsequently elaborated on and provided empirical support for this idea over the course of more than four decades of innovative psychobiological research. Although we are still a long way from fully understanding the specific pathways and processes by which prenatal experience can influence postnatal development, Gottlieb's research with precocial birds provided significant insights into the conditions and experiences of prenatal development involved in the achievement of species-typical perception and behavior. In particular, his elegant series of studies on the development of species identification in ducklings documented how the features and patterns of recurring prenatal sensory experience (including self-stimulation) guide and constrain the young individual's selective attention, perception, learning, and memory during both prenatal and postnatal periods. I review how this body of research supports the view that the structure and functions of the developing organism and its developmental ecology together form a relationship of mutual influence on the emergence, maintenance, and transformation of species-typical behavior. I also explore how Gottlieb's empirical demonstrations of the prenatal roots of so-called "instinctive" behavior provided a foundation for his conceptual efforts to define the links between developmental and evolutionary change. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 749,757, 2007. [source] Effects of redundant and nonredundant bimodal sensory stimulation on heart rate in bobwhite quail embryosDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2003Greg D. Reynolds Abstract Research with both animal embryos and human infants has provided evidence that information presented redundantly and in temporal synchrony across sensory modalities (intersensory redundancy) can guide selective attention, perceptual learning, and memory during early development. How this facilitation is achieved remains relatively unexamined. This study examined the effects of redundant versus nonredundant bimodal stimulation on a measure of physiological arousal (heart rate) in bobwhite quail embryos. Results show that quail embryos exposed to concurrent but nonredundant auditory and visual stimulation during the late stages of incubation exhibit significantly elevated heart rates following stimulus exposure and during stimulus reexposure when compared to embryos exposed to redundant and synchronous audiovisual stimulation, unimodal auditory stimulation, or no supplemental prenatal sensory stimulation. These findings indicate a functional distinction between redundant and nonredundant bimodal stimulation during early development and suggest that nonredundant bimodal stimulation during the prenatal period can raise arousal levels, thereby potentially interfering with the attentional capacities and perceptual learning of bobwhite quail. In contrast, intersensory redundancy appears to foster arousal levels that facilitate selective attention and perceptual learning during prenatal development. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 43: 304,310, 2003. [source] Evidence for reduced domain-specificity in auditory processing in autismDEVELOPMENTAL SCIENCE, Issue 6 2007Anna Järvinen-Pasley Neurological and behavioral findings indicate that atypical auditory processing characterizes autism. The present study tested the hypothesis that auditory processing is less domain-specific in autism than in typical development. Participants with autism and controls completed a pitch sequence discrimination task in which same/different judgments of music and/or speech stimulus pairs were made. A signal detection analysis showed no difference in pitch sensitivity across conditions in the autism group, while controls exhibited significantly poorer performance in conditions incorporating speech. The results are largely consistent with perceptual theories of autism, which propose that a processing bias towards featural/low-level information characterizes the disorder, as well as supporting the notion that such individuals exhibit selective attention to a limited number of simultaneously presented cues. [source] Intersensory redundancy educates selective attention in bobwhite quail embryosDEVELOPMENTAL SCIENCE, Issue 6 2006Robert Lickliter We assessed whether exposure to amodal properties in bimodal stimulation (e.g. rhythm, rate, duration) could educate attention to amodal properties in subsequent unimodal stimulation during prenatal development. Bobwhite quail embryos were exposed to an individual bobwhite maternal call under several experimental and control conditions during the day prior to hatching. Experimental groups received redundant auditory and visual exposure to the temporal features of an individual maternal call followed by unimodal auditory exposure to the same call immediately or after a 2-hr or 4-hr delay. Control groups received (1) the same exposure but in the reverse sequence (unimodal , redundant bimodal), (2) asynchronous bimodal , unimodal, (3) only unimodal exposure, or (4) only bimodal exposure. All experimental groups showed a significant preference for the familiar maternal call over a novel maternal call when tested 2 days after hatching, whereas none of the control groups showed a significant preference for the familiar call. These results indicate that intersensory redundancy can direct attention to amodal properties in bimodal stimulation and educate attention to the same amodal properties in subsequent unimodal stimulation where no intersensory redundancy is available. [source] The eyes have it: visual pop-out in infants and adultsDEVELOPMENTAL SCIENCE, Issue 2 2006Scott A. Adler Visual search studies with adults have shown that stimuli that contain a unique perceptual feature pop out from dissimilar distractors and are unaffected by the number of distractors. Studies with very young infants have suggested that they too might exhibit pop-out. However, infant studies have used paradigms in which pop-out is measured in seconds or minutes, whereas in adults pop-out occurs in milliseconds. In addition, with the previous infant paradigms the effects from higher cognitive processes such as memory cannot be separated from pop-out and selective attention. Consequently, whether infants exhibit the phenomenon of pop-out and have selective attention mechanisms as found in adults is not clear. This study was an initial attempt to design a paradigm that would provide a comparable measure between infants and adults, thereby allowing a more accurate determination of the developmental course of pop-out and selective attention mechanisms. To this end, we measured 3-month-olds' and adults' saccade latencies to visual arrays that contained either a + among Ls (target-present) or all Ls (target-absent) with set sizes of 1, 3, 5 or 8 items. In Experiment 1, infants' saccade latencies remained unchanged in the target-present conditions as set size increased, whereas their saccade latencies increased linearly in the target-absent conditions as set size increased. In Experiment 2, adults' saccade latencies in the target-present and target-absent conditions showed the same pattern as the infants. The only difference between the infants and adults was that the infants' saccade latencies were slower in every condition. These results indicate that infants do exhibit pop-out on a millisecond scale, that it is unaffected by the number of distractors, and likely have similar functioning selective attention mechanisms. Moreover, the results indicate that eye movement latencies are a more comparable and accurate measure for assessing the phenomenon of pop-out and underlying attentional mechanisms in infants. [source] Visual search in typically developing toddlers and toddlers with Fragile X or Williams syndromeDEVELOPMENTAL SCIENCE, Issue 1 2004Gaia Scerif Visual selective attention is the ability to attend to relevant visual information and ignore irrelevant stimuli. Little is known about its typical and atypical development in early childhood. Experiment 1 investigates typically developing toddlers' visual search for multiple targets on a touch-screen. Time to hit a target, distance between successively touched items, accuracy and error types revealed changes in 2- and 3-year-olds' vulnerability to manipulations of the search display. Experiment 2 examined search performance by toddlers with Fragile X syndrome (FXS) or Williams syndrome (WS). Both of these groups produced equivalent mean time and distance per touch as typically developing toddlers matched by chronological or mental age; but both produced a larger number of errors. Toddlers with WS confused distractors with targets more than the other groups; while toddlers with FXS perseverated on previously found targets. These findings provide information on how visual search typically develops in toddlers, and reveal distinct search deficits for atypically developing toddlers. [source] The intersensory origins of word-comprehension: an ecological,dynamic systems viewDEVELOPMENTAL SCIENCE, Issue 1 2001Lakshmi J. Gogate How do infants begin to understand spoken words? Recent research suggests that word comprehension develops from the early detection of intersensory relations between conventionally paired auditory speech patterns (words) and visible objects or actions. More importantly, in keeping with dynamic systems principles, the findings suggest that word comprehension develops from a dynamic and complementary relationship between the organism (the infant) and the environment (language addressed to the infant). In addition, parallel findings from speech and non-speech studies of intersensory perception provide evidence for domain general processes in the development of word comprehension. These research findings contrast with the view that a lexical acquisition device with specific lexical principles and innate constraints is required for early word comprehension. Furthermore, they suggest that learning of word,object relations is not merely an associative process. The data support an alternative view of the developmental process that emphasizes the dynamic and reciprocal interactions between general intersensory perception, selective attention and learning in infants, and the specific characteristics of maternal communication. [source] Attentional load modifies early activity in human primary visual cortexHUMAN BRAIN MAPPING, Issue 5 2009Karsten S. Rauss Abstract Recent theories of selective attention assume that the more attention is required by a task, the earlier are irrelevant stimuli filtered during perceptual processing. Previous functional MRI studies have demonstrated that primary visual cortex (V1) activation by peripheral distractors is reduced by higher task difficulty at fixation, but it remains unknown whether such changes affect initial processing in V1 or subsequent feedback. Here we manipulated attentional load at fixation while recording peripheral visual responses with high-density EEG in 28 healthy volunteers, which allowed us to track the exact time course of attention-related effects on V1. Our results show a modulation of the earliest component of the visual evoked potential (C1) as a function of attentional load. Additional topographic and source localization analyses corroborated this finding, with significant load-related differences observed throughout the first 100 ms post-stimulus. However, this effect was observed only when stimuli were presented in the upper visual field (VF), but not for symmetrical positions in the lower VF. Our findings demonstrate early filtering of irrelevant information under increased attentional demands, thus supporting models that assume a flexible mechanism of attentional selection, but reveal important functional asymmetries across the VF. Hum Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source] Finding a safe place to cross the road: the effect of distractors and the role of attention in children's identification of safe and dangerous road-crossing sitesINFANT AND CHILD DEVELOPMENT, Issue 2 2007Z. Tabibi Abstract Negotiating traffic requires the ability to focus attention on the traffic environment and ignore distracting stimuli. The aims of this study were (1) to examine the effect of distractors on children's ability to identify safe and dangerous road-crossing sites and (2) to examine the relationship between identification of safe/dangerous sites and attention (selective attention, attention switching, sustained attention and divided attention). Participants were 88 children (aged between 6 and 11 years) and 29 adults. Ability to identify safe and dangerous road-crossing sites was assessed using computer presentations of sites with and without visual and auditory distractions. Measures of attention were examined using the Test of Everyday Attention (child and adult versions). The ability to identify safe and dangerous road-crossing sites and performance on the attention tests were found to improve with increasing age. Correct identification of safe/dangerous road-crossing sites was related to selective attention and divided attention for children but not for adults. Road safety training should take into account the development of these skills. Copyright © 2007 John Wiley & Sons, Ltd. [source] The effects of spatial configuration on preschoolers' attention strategies, selective attention, and incidental learningINFANT AND CHILD DEVELOPMENT, Issue 3 2005Fran C. Blumberg Abstract This study investigated the effects of spatial arrangement on preschool children's selective attention and incidental learning. Three- and four-year old children were shown a multi-coloured box designated as a ,special place' containing miniature chairs and models of animals. One category of objects were designated as relevant and one as irrelevant. Relevant items were placed in each of the apparatus' corners, in the middle of its walls, or in two corners and in the middle of two walls. Findings revealed that children shown relevant items in corners demonstrated the greatest number of correct relocations for relevant items while those shown relevant items in the middle of the walls showed the greatest number of correct relocations for irrelevant items. Findings also suggest that for both age groups, the ability to recall relevant items may have been independent of their ability to demonstrate a selective attention strategy. Copyright © 2005 John Wiley & Sons, Ltd. [source] The Use of Safety Suitability Tests for The Assessment of Immigrant and Majority Group Job ApplicantsINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 3 2004Jan Te Nijenhuis Safety jobs, meaning jobs where employees are responsible for the safety of customers, other employees and/or public in general are of special importance for our present society and deserve continued attention from I/O psychologists. The central question addressed in this study is whether the scores on safety suitability tests are comparable for immigrants and majority group members. Use was made of test data on first-generation immigrants (N=786) and majority group members (N=584) who applied for blue collar jobs at the Dutch Railways and at regional bus companies. The tests used measured selective attention, attentional speed, continuous attention, perceptual-motor ability and general mental ability. Immigrants' mean scores are systematically below the level of the mean scores of the majority group. The tests appear to have a strong dimensional comparability between the different groups. There is very little indication of test bias. The increasing number of immigrants and the increase of safety jobs pose challenges for selection psychologists. It is suggested that continued use of safety suitability tests is needed to keep the number of safety accidents at a minimum. [source] Avoidance of Alcohol-Related Stimuli in Alcohol-Dependent InpatientsALCOHOLISM, Issue 8 2007J. M. Townshend Background: Previous research has shown an attentional bias toward drug-related stimuli in heavy social drinkers. Attentional orientation to drug-related cues may lead to increased craving and preoccupation with the drug and impaired ability to focus attention on nondrug-related activities, resulting in renewed drug taking or relapse from drug abstinence. Objective: The aim of this study was to investigate whether alcohol-dependent inpatients would differ in their selective attention toward alcohol-related stimuli in comparison with a group of social drinking controls. Method: Thirty-five alcohol-dependent inpatients were compared with a group of 39 social drinking controls matched for age, sex, and verbal IQ. Attentional bias was assessed using alcohol-related pictures in a dot probe detection task. Questionnaires were used to examine outcome expectancies after alcohol consumption, anxiety, mood, and craving. Results: The alcoholic inpatients showed a bias away from the alcohol-related stimuli, scored higher on alcohol outcome expectancies, and on anxiety measures (both state and trait). They also presented with more negative mood compared with the control group. Craving was higher in the alcoholic group for the factor "loss of control over drinking." Conclusions: Alcoholic inpatients undergoing treatment based on the 12-step treatment of Alcoholics Anonymous (Minnesota model), which includes counseling, and intensive group, individual, and family psychotherapy, show an avoidance for drug-related stimuli and a perception of loss of control over drinking. We suggest that their increased perception of loss of control over drinking produces the avoidance from the drug-related stimuli. [source] Multicomponent attention deficits in attention deficit hyperactivity disorderPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 2 2007M GÜNAY KILIÇ md Abstract The aim of this study was to examine the specific aspects of attention, such as selective attention, sustained attention, and short-term memory in children with attention deficit hyperactivity disorder, combined subtype (ADHD-C). A total of 40 children with a diagnosis of ADHD from the 4th edition of the Diagnostic and Statistical Manual, aged 6,11 years old were compared with 40 controls matched for age and gender on a battery of tests. Short-term memory span and attention was measured by Visual Aural Digit Span Test,Revised. Stroop test and the Turkish version of Cancellation Test were used to assess selective and sustained attention, respectively. In order to check for factor structure in two groups on the test scores, principal component analysis was conducted for both groups separately. Relative to the comparison children, children with ADHD showed significant deficits on tests that are related to different aspects of attention. The results are consistent with the theories explaining the biological basis of ADHD by scattered attention networks in the brain, which have reciprocal dynamic interactions. Further comparative studies are needed to elucidate whether the cognitive processes that are known to be assessed by these tests are specific to ADHD. [source] Cognitive and mood changes in men undergoing intermittent combined androgen blockade for non-metastatic prostate cancerPSYCHO-ONCOLOGY, Issue 3 2009M.M. Cherrier Abstract Purpose: Men with prostate-specific antigen (PSA)-only relapse of prostate cancer after primary therapy are generally fully functional and asymptomatic with a life expectancy of up to 10 or more years. Androgen deprivation therapy (ADT) is a common treatment option. This study examined mood and cognitive changes in otherwise healthy men with prostate cancer prior to, during and after ADT. Experimental design: Twenty hormone naïve, eugonadal prostate cancer patients without evidence of metastases and with a rising PSA were treated with intermittent ADT consisting of 9 months of complete androgen blockade (CAB) achieved with combined leuprolide and flutamide followed by an ,off treatment' period. Cognitive function tests and mood measures were administered at baseline, after 3 and 9 months of ADT and after 3 months of no treatment. Twenty healthy control patients without prostate cancer range matched for age and education were tested at the same time intervals. Results: ADT patients evidenced a significant decline in spatial reasoning, spatial abilities and working memory during treatment compared with baseline. No changes were noted for measures of verbal or spatial memory, selective attention or language. Significant changes in self-rated mood such as increased depression, tension, anxiety, fatigue and irritability were evident during treatment compared with baseline for ADT patients. No significant changes in either cognitive tests or mood measures were noted for the healthy control group. Conclusions: These findings, suggest that 9 months of combined androgen blockade may result in some adverse changes in cognition and mood. However, many but not all of these changes can return to baseline after cessation of ADT. Copyright © 2008 John Wiley & Sons, Ltd. [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] Stress and selective attention: The interplay of mood, cortisol levels, and emotional information processingPSYCHOPHYSIOLOGY, Issue 6 2002Mark A. Ellenbogen The effects of a stressful challenge on the processing of emotional words were examined in college students. Stress induction was achieved using a competitive computer task, where the individual either repeatedly lost or won against a confederate. Mood, attention, and cortisol were recorded during the study. There were four findings: (1) Participants in the negative stressor condition were faster to shift attention away from negative words than positive or neutral words; (2) attentional shifts away from negative words were associated with stress-induced mood lowering; (3) participants in the negative stress condition with elevated scores on the Beck Depression Inventory were slow to disengage attention from all stimuli; and (4) elevated depression scores were associated with lower cortisol change from baseline during the experimental phase, and with higher cortisol levels during the recovery phase. These findings point to information-processing strategies as a means to regulate emotion, and to atypical features of cognitive and adrenocortical function that may serve as putative risk markers of depression. [source] Nonspatial intermodal selective attention is mediated by sensory brain areas: Evidence from event-related potentialsPSYCHOPHYSIOLOGY, Issue 5 2001Durk Talsma The present study focuses on the question of whether inter- and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while subjects were presented a random sequence of visual and auditory stimuli. They were instructed to attend to nonspatial attributes of either auditory or visual stimuli and to detect occasional target stimuli within the attended channel. An occipital selection negativity was found for intramodal attention to visual stimuli. Visual intermodal attention was also manifested in a similar negativity. A symmetrical dipole pair in the medial inferior occipital areas could account for the intramodal effects. Dipole pairs for the intermodal attention effect had a slightly more posterior location compared to the dipole pair for the intramodal effect. Auditory intermodal attention was manifested in an early enhanced negativity overlapping with the N1 and P2 components, which was localized using a symmetrical dipole pair in the lateral auditory cortex. The onset of the intramodal attention effect was somewhat later (around 200 ms), and was reflected in a frontal processing negativity. The present results indicate that intra- and intermodal forms of attention were indeed similar for visual stimuli. Auditory data suggest the involvement of multiple brain areas. [source] Reduced activation in lateral prefrontal cortex and anterior cingulate during attention and cognitive control functions in medication-naïve adolescents with depression compared to controlsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 3 2009Rozmin Halari Background:, There is increasing recognition of major depressive disorder (MDD) in adolescence. In adult MDD, abnormalities of fronto-striatal and fronto-cingulate circuitries mediating cognitive control functions have been implicated in the pathogenesis and been related to problems with controlling negative thoughts. No neuroimaging studies of cognitive control functions, however, exist in paediatric depression. This study investigated whether medication-naïve adolescents with MDD show abnormal brain activation of fronto-striatal and fronto-cingulate networks when performing tasks of attentional and cognitive control. Methods:, Event-related functional magnetic resonance imaging was used to compare brain activation between 21 medication-naïve adolescents with a first-episode of MDD aged 14,17 years and 21 healthy adolescents, matched for handedness, age, sex, demographics and IQ. Activation paradigms were tasks of selective attention (Simon task), attentional switching (Switch task), and motor response inhibition and error detection (Stop task). Results:, In all three tasks, adolescents with depression compared to healthy controls demonstrated reduced activation in task-relevant right dorsolateral (DLPFC), inferior prefrontal cortex (IFC) and anterior cingulate gyrus (ACG). Additional areas of relatively reduced activation were in the parietal lobes during the Stop and Switch tasks, putamen, insula and temporal lobes during the Switch task and precuneus during the Simon task. Conclusions:, This study shows first evidence that medication-naïve adolescents with MDD are characterised by abnormal function in ACG and right lateral prefrontal cortex during tasks of attention and performance monitoring, suggesting an early pathogenesis of these functional abnormalities attributed to MDD. [source] Contributions of spectral frequency analyses to the study of P50 ERP amplitude and suppression in bipolar disorder with or without a history of psychosisBIPOLAR DISORDERS, Issue 7 2008Christine A Carroll Objective:, The present study investigated event-related brain potential (ERP) indices of auditory processing and sensory gating in bipolar disorder and subgroups of bipolar patients with or without a history of psychosis using the P50 dual-click procedure. Auditory-evoked activity in two discrete frequency bands also was explored to distinguish between sensory registration and selective attention deficits. Methods:, Thirty-one individuals with bipolar disorder and 28 non-psychiatric controls were compared on ERP indices of auditory processing using a dual-click procedure. In addition to conventional P50 ERP peak-picking techniques, quantitative frequency analyses were applied to the ERP data to isolate stages of information processing associated with sensory registration (20,50 Hz; gamma band) and selective attention (0,20 Hz; low-frequency band). Results:, Compared to the non-psychiatric control group, patients with bipolar disorder exhibited reduced S1 response magnitudes for the conventional P50 peak-picking and low-frequency response analyses. A bipolar subgroup effect suggested that the attenuated S1 magnitudes from the P50 peak-picking and low-frequency analyses were largely attributable to patients without a history of psychosis. Conclusions:, The analysis of distinct frequency bands of the auditory-evoked response elicited during the dual-click procedure allowed further specification of the nature of auditory sensory processing and gating deficits in bipolar disorder with or without a history of psychosis. The observed S1 effects in the low-frequency band suggest selective attention deficits in bipolar patients, especially those patients without a history of psychosis, which may reflect a diminished capacity to selectively attend to salient stimuli as opposed to impairments of inhibitory sensory processes. [source] Stroop performance in bipolar disorder: further evidence for abnormalities in the ventral prefrontal cortexBIPOLAR DISORDERS, Issue 1 2006Dina M Kronhaus Objectives:, Bipolar patients are impaired in Stroop task performance, a measure of selective attention. Structural and functional abnormalities in task-associated regions, in particular the prefrontal cortex (PFC), have been reported in this population. We aimed to examine the relationship between functional abnormalities, impaired task performance and the severity of depressive symptoms in bipolar patients. Methods:, Remitted bipolar patients (n = 10; all medicated), either euthymic or with subsyndromal depression, and age-matched control subjects (n = 11) viewed 10 alternating blocks of incongruent Stroop and control stimuli, naming the colour of the ink. Neural response was measured using functional magnetic resonance imaging. We computed between-group differences in neural response and within-group correlations with mood and anxiety. Results:, There were no significant between-group differences in task performance. During the Stroop condition, controls demonstrated greater activation of visual and dorsolateral and ventrolateral prefrontal cortical areas; bipolar patients demonstrated relative deactivation within orbital and medial prefrontal cortices. Depression scores showed a trend towards a negative correlation with the magnitude of orbitofrontal cortex deactivation in bipolar patients, whereas state anxiety correlated positively with activation of dorsolateral PFC and precuneus in controls. Conclusions:, Our findings confirm previous reports of decreased ventral prefrontal activity during Stroop task performance in bipolar patients, and suggest a possible negative correlation between this and depression severity in bipolar patients. These findings further highlight the ventromedial PFC as a potential candidate for illness related dysfunction in bipolar disorder. [source] | ||||||||||||||||