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Sample records for aberrant prefrontal salience

  1. Assessing the construct validity of aberrant salience

    Kristin Schmidt

    2009-12-01

    Full Text Available We sought to validate the psychometric properties of a recently developed paradigm that aims to measure salience attribution processes proposed to contribute to positive psychotic symptoms, the Salience Attribution Test (SAT. The “aberrant salience” measure from the SAT showed good face validity in previous results, with elevated scores both in high-schizotypy individuals, and in patients with schizophrenia suffering from delusions. Exploring the construct validity of salience attribution variables derived from the SAT is important, since other factors, including latent inhibition/learned irrelevance, attention, probabilistic reward learning, sensitivity to probability, general cognitive ability and working memory could influence these measures. Fifty healthy participants completed schizotypy scales, the SAT, a learned irrelevance task, and a number of other cognitive tasks tapping into potentially confounding processes. Behavioural measures of interest from each task were entered into a principal components analysis, which yielded a five-factor structure accounting for ~75% percent of the variance in behaviour. Implicit aberrant salience was found to load onto its own factor, which was associated with elevated “Introvertive Anhedonia” schizotypy, replicating our previous finding. Learned irrelevance loaded onto a separate factor, which also included implicit adaptive salience, but was not associated with schizotypy. Explicit adaptive and aberrant salience, along with a measure of probabilistic learning, loaded onto a further factor, though this also did not correlate with schizotypy. These results suggest that the measures of learned irrelevance and implicit adaptive salience might be based on similar underlying processes, which are dissociable both from implicit aberrant salience and explicit measures of salience.

  2. Do patients with schizophrenia exhibit aberrant salience?

    Roiser, J. P.; Stephan, K E; den Ouden, H. E. M.; Barnes, T. R. E.; Friston, K.J.; Joyce, E. M.

    2009-01-01

    BACKGROUND: It has been suggested that some psychotic symptoms reflect ‘aberrant salience’, related to dysfunctional reward learning. To test this hypothesis we investigated whether patients with schizophrenia showed impaired learning of task-relevant stimulusreinforcement associations in the presence of distracting task-irrelevant cues. METHODS: We tested 20 medicated patients with schizophrenia and 17 controls on a reaction time game, the Salience Attribution Test. In this game, ...

  3. Prefrontal /accumbal catecholamine system processes high motivational salience.

    Stefano Puglisi-Allegra

    2012-06-01

    Neural mechanisms mediating motivational salience attribution are, therefore, very important for individual and species survival and for well-being. However, these neural mechanisms could be implicated in attribution of abnormal motivational salience to different stimuli leading to maladaptive compulsive seeking or avoidance. We have offered the first evidence that prefrontal cortical norepinephrine transmission is a necessary condition for motivational salience attribution to highly salient stimuli, through modulation of dopamine in the nucleus accumbens, a brain area involved in all motivated behaviors. Moreover, we have shown that prefrontal-accumbal catecholamine system determines approach or avoidance responses to both reward- and aversion-related stimuli only when the salience of the unconditioned stimulus is high enough to induce sustained catecholamine activation, thus affirming that this system processes motivational salience attribution selectively to highly salient events.

  4. The Electrophysiological Signature of Motivational Salience in Mice and Implications for Schizophrenia

    Moessnang, Carolin; Habel, Ute; Schneider, Frank; Siegel, Steven J.

    2012-01-01

    According to the aberrant-salience hypothesis, attribution of motivational salience is severely disrupted in patients with schizophrenia. To provide a translational approach for investigating underlying mechanisms, neural correlates of salience attribution were examined in normal mice and in a MK-801 model of schizophrenia. Electrophysiological responses to standard and deviant tones were assessed in the medial prefrontal cortex (mPFC) using an auditory oddball paradigm. Motivational salience...

  5. Aberrant structural and functional connectivity in the salience network and central executive network circuit in schizophrenia.

    Chen, Quan; Chen, Xingui; He, Xiaoxuan; Wang, Lu; Wang, Kai; Qiu, Bensheng

    2016-08-01

    Consistent structural and functional abnormities have been detected in the salience network (SN) and the central-executive network (CEN) in schizophrenia. SN, known for its critical role in switching CEN and default-mode network (DMN) during cognitively demanding tasks, is proved to show aberrant regulation on the interaction between DMN and CEN in schizophrenia. However, it has not been elucidated whether there is a direct alteration of structural and functional connectivity between SN and CEN. 22 schizophrenia patients and 21 healthy controls were recruited for functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) in present study. The results show that schizophrenia patients had lower fractional anisotropy (FA) in right inferior long fasciculus (ILF), left inferior fronto-occipital fasciculus (IFOF) and callosal body than healthy controls. Significantly reduced functional connectivity was also found between right fronto-insular cortex (rFIC) and right posterior parietal cortex (rPPC). FA in right ILF was positively correlated with the functional connectivity of rFIC-rPPC. Therefore, we proposed a disruption of structural and functional connectivity and a positive anatomo-functional relationship in SN-CEN circuit, which might account for a core feature of schizophrenia. PMID:27233217

  6. Electrophysiological Correlates of Aberrant Motivated Attention and Salience Processing in Unaffected Relatives of Schizophrenia Patients.

    Andersen, Elizabeth H; Campbell, Alana M; Schipul, Sarah E; Bellion, Carolyn M; Donkers, Franc C L; Evans, Anna M; Belger, Aysenil

    2016-01-01

    Patients with schizophrenia (SCZ) exhibit debilitating deficits in attention and affective processing, which are often resistant to treatment and associated with poor functional outcomes. Impaired orientation to task-relevant target information has been indexed by diminished P3b event-related potentials in patients, as well as their unaffected first-degree relatives, suggesting that P3b may be a vulnerability marker for schizophrenia. Despite intact affective valence processing, patients are unable to employ cognitive change strategies to reduce electrophysiological responses to aversive stimuli. Less is known about the attentional processing of emotionally salient task-irrelevant information in patients and unaffected first-degree relatives. The goal of the present study was to examine the neural correlates of salience processing, as indexed by the late positive potential (LPP), during the processing of emotionally salient distractor stimuli in 31 patients with SCZ, 28 first-degree relatives, and 47 control participants using an oddball paradigm. Results indicated that despite intact novelty detection (P3a), both SCZ and first-degree relatives demonstrated deficiencies in attentional processing, reflected in attenuated target-P3b, and aberrant motivated attention, with reduced early-LPP amplitudes for aversive stimuli relative to controls. First-degree relatives revealed a unique enhancement of the late-LPP response, possibly underlying an exaggerated evaluation of salient information and a compensatory engagement of neural circuitry. Furthermore, reduced early-LPP and target-P3b amplitudes were associated with enhanced symptom severity. These findings suggest that, in addition to P3b, LPP may be useful for monitoring clinical state. Future studies will explore the value of P3 and LPP responses as vulnerability markers for early detection and prediction of psychopathology. PMID:26251457

  7. Aberrant intrinsic connectivity of hippocampus and amygdala overlap in the fronto-insular and dorsomedial-prefrontal cortex in major depressive disorder

    Masoud Tahmasian

    2013-10-01

    Full Text Available Neuroimaging studies of major depressive disorder (MDD have consistently observed functional and structural changes of the hippocampus (HP and amygdale (AY. Thus, these brain regions appear to be critical elements of the pathophysiology of MDD. The HP and AY directly interact and show broad and overlapping intrinsic functional connectivity (iFC to other brain regions. Therefore, we hypothesized the HP and AY would show a corresponding pattern of aberrant intrinsic connectivity in MDD. Resting-state functional MRI was acquired from 21 patients with MDD and 20 healthy controls. ß-maps of region-of-interest-based FC for bilateral body of the HP and basolateral AY were used as surrogates for iFC of the HP and AY. ANOVA was used to compare ß-maps between MDD and healthy control groups, and included covariates for age and gender as well as grey matter volume of the HP and AY. The HP and AY of MDD patient’s showed an overlapping pattern of reduced FC to the dorsomedial prefrontal cortex and fronto-insular operculum. Both of these regions are known to regulate the interactions among intrinsic networks (i.e. default mode, central executive, and salience networks that are disrupted in MDD. These results provide the first evidence of overlapping aberrant HP and AY intrinsic connectivity in MDD. Our findings suggest that aberrant HP and AY connectivity may interact with dysfunctional intrinsic network activity in MDD.

  8. Dopamine D4 Receptor Transmission in the Prefrontal Cortex Controls the Salience of Emotional Memory via Modulation of Calcium Calmodulin–Dependent Kinase II

    Lauzon, Nicole M; Ahmad, Tasha; Laviolette, Steven R

    2011-01-01

    Dopamine (DA) signaling in the medial prefrontal cortex (mPFC) plays a critical role in the processing of emotional information and memory encoding. Activation of DA D4 receptors within the prelimbic (PLC) division of the mPFC bidirectionally modulates emotional memory by strongly potentiating the salience of normally nonsalient emotional memories but blocking the acquisition of suprathreshold emotionally salient fear memories. Previous in vitro studies have shown that activation of cortical ...

  9. Insular dysfunction within the salience network is associated with severity of symptoms and aberrant inter-network connectivity in major depressive disorder

    Andrei Manoliu

    2014-01-01

    Full Text Available Major depressive disorder (MDD is characterized by altered intrinsic functional connectivity within (intra-iFC intrinsic connectivity networks (ICNs, such as the Default Mode- (DMN, Salience- (SN and Central Executive Network (CEN. It has been proposed that aberrant switching between DMN-mediated self-referential and CEN-mediated goal-directed cognitive processes might contribute to MDD, possibly explaining patients’ difficulties to disengage the processing of self-focused, often negatively biased thoughts. Recently, it has been shown that the right anterior insula (rAI within the SN is modulating DMN/CEN interactions. Since structural and functional alterations within the AI have been frequently reported in MDD, we hypothesized that aberrant intra-iFC in the SN´s rAI is associated with both aberrant iFC between DMN and CEN (inter-iFC and severity of symptoms in MDD. Twenty-five patients with MDD and 25 healthy controls were assessed using resting-state fMRI (rs-fMRI and psychometric examination. High-model-order independent component analysis (ICA of rs-fMRI data was performed to identify ICNs including DMN, SN, and CEN. Intra-iFC within and inter-iFC between distinct subsystems of the DMN, SN and CEN were calculated, compared between groups and correlated with the severity of symptoms. Patients with MDD showed (1 decreased intra-iFC within the SN´s rAI, (2 decreased inter-iFC between the DMN and CEN and (3 increased inter-iFC between the SN and DMN. Moreover, decreased intra-iFC in the SN´s rAI was associated with severity of symptoms and aberrant DMN/CEN interactions, with the latter losing significance after correction for multiple comparisons. Our results provide evidence for a relationship between aberrant intra-iFC in the salience network’s rAI, aberrant DMN/CEN interactions and severity of symptoms, suggesting a link between aberrant salience mapping, abnormal coordination of DMN/CEN based cognitive processes and psychopathology

  10. Prefrontal/accumbal catecholamine system determines motivational salience attribution to both reward- and aversion-related stimuli

    Ventura, Rossella; Morrone, Cristina; Puglisi-Allegra, Stefano

    2007-01-01

    Recent evidence suggests that rewarding and aversive stimuli affect the same brain areas, including medial prefrontal cortex and nucleus accumbens. Although nucleus accumbens is known to respond to salient stimuli, regardless of their hedonic valence, with selective increased dopamine release, little is known about the role of prefrontal cortex in reward- and aversion-related motivation or about the neurotransmitters involved. Here we find that selective norepinephrine depletion in medial pre...

  11. The electrophysiological signature of motivational salience in mice and implications for schizophrenia.

    Moessnang, Carolin; Habel, Ute; Schneider, Frank; Siegel, Steven J

    2012-12-01

    According to the aberrant-salience hypothesis, attribution of motivational salience is severely disrupted in patients with schizophrenia. To provide a translational approach for investigating underlying mechanisms, neural correlates of salience attribution were examined in normal mice and in a MK-801 model of schizophrenia. Electrophysiological responses to standard and deviant tones were assessed in the medial prefrontal cortex (mPFC) using an auditory oddball paradigm. Motivational salience was induced by aversive conditioning to the deviant tone. Analysis of the auditory evoked potential (AEP) showed selective modulation of the late frontal negativity (LFN) by motivational salience, which persisted throughout a 4-week delay. MK-801, an N-methyl-D-aspartic acid receptor antagonist, abolished this differential response to motivational salience in conditioned mice. In contrast, a pronounced LFN response was observed towards the deviant, ie, perceptually salient tone, in nonconditioned mice. The finding of a selective modulation of a late frontal slow wave suggests increased top-down processing and emotional evaluation of motivationally salient stimuli. In particular, the LFN is discussed as the mouse analog to the human stimulus preceding negativity, which reflects preparatory processes in anticipation of reward or punishment. MK-801 led to a disruption of the normal response in conditioned and nonconditioned mice, including an aberrantly increased LFN in nonconditioned mice. This pattern of 'false-negative' and 'false-positive' responses suggests a degradation of salience attribution, which points to mPFC responses to be relevant for translational research on cognitive alterations in schizophrenia. PMID:22910459

  12. Abnormal salience signaling in schizophrenia: the role of integrative beta oscillations

    Liddle, Elizabeth B.; Price, Darren; Palaniyappan, Lena; Brookes, Matthew J.; Robson, Siân E.; Hall, Emma L.; Morris, Peter G; Liddle, Peter F.

    2016-01-01

    Aberrant salience attribution and cerebral dysconnectivity both have strong evidential support as core dysfunctions in schizophrenia. Aberrant salience arising from an excess of dopamine activity has been implicated in delusions and hallucinations, exaggerating the significance of everyday occurrences and thus leading to perceptual distortions and delusional causal inferences. Meanwhile, abnormalities in key nodes of a salience brain network have been implicated in other characteristic sympto...

  13. Aberrant Intrinsic Connectivity of Hippocampus and Amygdala Overlap in the Fronto-Insular and Dorsomedial-Prefrontal Cortex in Major Depressive Disorder

    Tahmasian, Masoud; Knight, David C.; Manoliu, Andrei; Schwerthöffer, Dirk; Scherr, Martin; Meng, Chun; Shao, Junming; Peters, Henning; Doll, Anselm; Khazaie, Habibolah; Drzezga, Alexander; Bäuml, Josef; Zimmer, Claus; Förstl, Hans; Wohlschläger, Afra M.

    2013-01-01

    Neuroimaging studies of major depressive disorder (MDD) have consistently observed functional and structural changes of the hippocampus (HP) and amygdale (AY). Thus, these brain regions appear to be critical elements of the pathophysiology of MDD. The HP and AY directly interact and show broad and overlapping intrinsic functional connectivity (iFC) to other brain regions. Therefore, we hypothesized the HP and AY would show a corresponding pattern of aberrant intrinsic connectivity in MDD. Res...

  14. Aberrant Effective Connectivity in Schizophrenia Patients During Appetitive Conditioning

    Andreea Oliviana Diaconescu

    2011-01-01

    Full Text Available It has recently been suggested that schizophrenia involves dysfunction in brain connectivity at a neural level, and a dysfunction in reward processing at a behavioural level. The purpose of the present study was to link these two levels of analyses by examining effective connectivity patterns between brain regions mediating reward learning in patients with schizophrenia and healthy, age-matched controls. To this aim, we used functional magnetic resonance imaging (fMRI and galvanic skin recordings (GSR while patients and controls performed an appetitive conditioning experiment with visual cues as the conditioned (CS stimuli, and monetary reward as the appetitive unconditioned stimulus (US. Based on explicit stimulus contingency ratings, conditioning occurred in both groups; however, based on implicit, physiological GSR measures, patients failed to show differences between CS+ and CS- conditions. Healthy controls exhibited increased blood-oxygen-level dependent (BOLD activity across striatal, hippocampal and prefrontal regions and increased effective connectivity from the ventral striatum (VS to the orbitofrontal cortex (OFC BA 11 in the CS+ compared to the CS- condition. Compared to controls, patients showed increased BOLD activity across a similar network of brain regions, and increased effective connectivity from the striatum to hippocampus and prefrontal regions in the CS- compared to the CS+ condition. The findings of increased BOLD activity and effective connectivity in response to the CS- in patients with schizophrenia offer insight into the aberrant assignment of motivational salience to non-reinforced stimuli during conditioning that is thought to accompany schizophrenia.

  15. 精神分裂症患者脑静息态默认网络和中心执行网络及突显网络关系的初步探讨%Aberrant functional connectivity within and across the default mode, central-executive, and salience network in patients with schizophrenia: a resting-state functional magnetic resonance imaging study

    黄欢; 王惠玲; 周媛; 陈军; 邹寄林; 陈诚; 吴士豪; 李培福; 蒋田仔

    2015-01-01

    (ROI) analysis were used to investigate functional connectivity (FC) of the DMN,CEN,and SN in 74 patients with schizophrenia (SZ) and 79 ageand gender-matched normal controls (NC).Medial prefrontal cortex (MPFC) was selected as seed region for identifying the DMN and CEN while right anterior insula (rAI) for the SN.Voxel-wise functional connectivity analyses were performed between MPFC and rAI while pair-wise functional connectivity analyses were conducted across DMN,CEN,and SN.Results Concerning the MPFC,SZ showed increased functional connectivity,comparing with NC,with bilateral dorsolateral prefrontal cortex (left:-0.02 ±0.18 vs.-0.12± 0.12,t=4.25,P<0.01;right:-0.02±0.11 vs.-0.10±0.10,t=5.40,P<0.01) and bilateral putamen (left:0.14± 0.12 vs.0.04±0.10,t=5.03,P<0.01;right:0.13±0.11 vs.0.03±0.98,t=4.96,P<0.01).With regard to rAI,increased functional connectivity between rAI and left middle frontal cortex (-0.05±0.17 vs.-0.07±0.17,t=4.60,P<0.01) and between rAI and precuneus/posterior cingulate cortex (0.01±0.13 vs.-0.09±0.14,t=4.01,P<0.01) were found in SZ comparison to NC (gaussian random field thaeory-corrected;voxel level P<0.01,cluster level P<0.05).Additionally,SZ also showed enhanced interconnectivity strengths of DMN-CEN and DMN-SN (Bonferroni-corrected,P<0.05).Furthermore,partial correlation analyses showed that the increased functional connectivity between rAI and precuneus/posterior cingulate cortex was significantly correlated with PANSS-positve symptoms (r-0.232,P=0.025).Positive relationships were found between the duration of illness and functional connectivity between rAI and left middle frontal cortex (r=0.288,P=0.007) and between rAI and precuneus/posterior cingulate cortex (r=0.196,P=0.049).Conclusions This study provides evidence for resting state functional connectivity abnormalities of DMN,CEN,and SN in patients with schizophrenia.These aberrant functional connectivities between some key brain regions of three networks

  16. Elicited Salience and Salience-Based Level-k

    Wolff, Irenaeus

    2016-01-01

    A level-k model based on a specific salience-pattern is the only model in the literature that accounts for behaviour in hide-and-seek games. This paper presents nine different experiments designed to measure salience. The elicited salience patterns tend to be similar, but none of them is similar to the pattern needed to allow the level-k model explain the hide-and-seek data. When based on any of the empirical salience measures, the salience-based level-k model does not fit the data well. p...

  17. Cannabinoid modulation of functional connectivity within regions processing attentional salience.

    Bhattacharyya, Sagnik; Falkenberg, Irina; Martin-Santos, Rocio; Atakan, Zerrin; Crippa, Jose A; Giampietro, Vincent; Brammer, Mick; McGuire, Philip

    2015-05-01

    There is now considerable evidence to support the hypothesis that psychotic symptoms are the result of abnormal salience attribution, and that the attribution of salience is largely mediated through the prefrontal cortex, the striatum, and the hippocampus. Although these areas show differential activation under the influence of delta-9-tetrahydrocannabinol (delta-9-THC) and cannabidiol (CBD), the two major derivatives of cannabis sativa, little is known about the effects of these cannabinoids on the functional connectivity between these regions. We investigated this in healthy occasional cannabis users by employing event-related functional magnetic resonance imaging (fMRI) following oral administration of delta-9-THC, CBD, or a placebo capsule. Employing a seed cluster-based functional connectivity analysis that involved using the average time series from each seed cluster for a whole-brain correlational analysis, we investigated the effect of drug condition on functional connectivity between the seed clusters and the rest of the brain during an oddball salience processing task. Relative to the placebo condition, delta-9-THC and CBD had opposite effects on the functional connectivity between the dorsal striatum, the prefrontal cortex, and the hippocampus. Delta-9-THC reduced fronto-striatal connectivity, which was related to its effect on task performance, whereas this connection was enhanced by CBD. Conversely, mediotemporal-prefrontal connectivity was enhanced by delta-9-THC and reduced by CBD. Our results suggest that the functional integration of brain regions involved in salience processing is differentially modulated by single doses of delta-9-THC and CBD and that this relates to the processing of salient stimuli. PMID:25249057

  18. Salience and Asset Prices

    Bordalo, Pedro; Gennaioli, Nicola; Shleifer, Andrei

    2013-01-01

    We present a simple model of asset pricing in which payoff salience drives investors' demand for risky assets. The key implication is that extreme payoffs receive disproportionate weight in the market valuation of assets. The model accounts for several puzzles in finance in an intuitive way, including preference for assets with a chance of very high payoffs, an aggregate equity premium, and countercyclical variation in stock market returns.

  19. Saliency changes appearance.

    Dirk Kerzel

    Full Text Available Numerous studies have suggested that the deployment of attention is linked to saliency. In contrast, very little is known about how salient objects are perceived. To probe the perception of salient elements, observers compared two horizontally aligned stimuli in an array of eight elements. One of them was salient because of its orientation or direction of motion. We observed that the perceived luminance contrast or color saturation of the salient element increased: the salient stimulus looked even more salient. We explored the possibility that changes in appearance were caused by attention. We chose an event-related potential indexing attentional selection, the N2pc, to answer this question. The absence of an N2pc to the salient object provides preliminary evidence against involuntary attentional capture by the salient element. We suggest that signals from a master saliency map flow back into individual feature maps. These signals boost the perceived feature contrast of salient objects, even on perceptual dimensions different from the one that initially defined saliency.

  20. The Social Salience Hypothesis of Oxytocin.

    Shamay-Tsoory, Simone G; Abu-Akel, Ahmad

    2016-02-01

    Oxytocin is a nonapeptide that also serves as a neuromodulator in the human central nervous system. Over the last decade, a sizeable body of literature has examined its effects on social behavior in humans. These studies show that oxytocin modulates various aspects of social behaviors such as empathy, trust, in-group preference, and memory of socially relevant cues. Several theoretical formulations have attempted to explain the effects of oxytocin. The prosocial account argues that oxytocin mainly enhances affiliative prosocial behaviors; the fear/stress theory suggests that oxytocin affects social performance by attenuating stress; and the in-/out-group approach proposes that oxytocin regulates cooperation and conflict among humans in the context of intergroup relations. Nonetheless, accumulating evidence reveals that the effects of oxytocin are dependent on a variety of contextual aspects and the individual's characteristics and can induce antisocial effects including aggression and envy. In an attempt to reconcile these accounts, we suggest a theoretical framework that focuses on the overarching role of oxytocin in regulating the salience of social cues through its interaction with the dopaminergic system. Crucially, the salience effect modulates attention orienting responses to external contextual social cues (e.g., competitive vs. cooperative environment) but is dependent on baseline individual differences such as gender, personality traits, and degree of psychopathology. This view could have important implications for the therapeutic applications of oxytocin in conditions characterized with aberrant social behavior. PMID:26321019

  1. Abnormal salience signaling in schizophrenia: The role of integrative beta oscillations.

    Liddle, Elizabeth B; Price, Darren; Palaniyappan, Lena; Brookes, Matthew J; Robson, Siân E; Hall, Emma L; Morris, Peter G; Liddle, Peter F

    2016-04-01

    Aberrant salience attribution and cerebral dysconnectivity both have strong evidential support as core dysfunctions in schizophrenia. Aberrant salience arising from an excess of dopamine activity has been implicated in delusions and hallucinations, exaggerating the significance of everyday occurrences and thus leading to perceptual distortions and delusional causal inferences. Meanwhile, abnormalities in key nodes of a salience brain network have been implicated in other characteristic symptoms, including the disorganization and impoverishment of mental activity. A substantial body of literature reports disruption to brain network connectivity in schizophrenia. Electrical oscillations likely play a key role in the coordination of brain activity at spatially remote sites, and evidence implicates beta band oscillations in long-range integrative processes. We used magnetoencephalography and a task designed to disambiguate responses to relevant from irrelevant stimuli to investigate beta oscillations in nodes of a network implicated in salience detection and previously shown to be structurally and functionally abnormal in schizophrenia. Healthy participants, as expected, produced an enhanced beta synchronization to behaviorally relevant, as compared to irrelevant, stimuli, while patients with schizophrenia showed the reverse pattern: a greater beta synchronization in response to irrelevant than to relevant stimuli. These findings not only support both the aberrant salience and disconnectivity hypotheses, but indicate a common mechanism that allows us to integrate them into a single framework for understanding schizophrenia in terms of disrupted recruitment of contextually appropriate brain networks. Hum Brain Mapp 37:1361-1374, 2016. © 2016 Wiley Periodicals, Inc. PMID:26853904

  2. Chromosomal aberration

    Chromosomal aberrations are classified into two types, chromosome-type and chromatid-type. Chromosom-type aberrations include terminal deletion, dicentric, ring and interstitial deletion, and chromatid-type aberrations include achromatic lesion, chromatid deletion, isochromatid deletion and chromatid exchange. Clastogens which induce chromosomal aberration are divided into ''S-dependent'' agents and ''S-independent''. It might mean whether they can induce double strand breaks independent of the S phase or not. Double strand breaks may be the ultimate lesions to induce chromosomal aberrations. Caffeine added even in the G2 phase appeared to modify the frequency of chromatid aberrations induced by X-rays and mitomycin C. Those might suggest that the G2 phase involves in the chromatid aberration formation. The double strand breaks might be repaired by ''G2 repair system'', the error of which might yield breakage types of chromatid aberrations and the by-pass of which might yield chromatid exchanges. Chromosome-type aberrations might be formed in the G1 phase. (author)

  3. Decreased Intra- and Inter-Salience Network Functional Connectivity is Related to Trait Anxiety in Adolescents

    Geng, Haiyang; Li, Xuebing; Chen, Jie; Li, Xinying; Gu, Ruolei

    2016-01-01

    Objective: Adolescence is a critical period for the vulnerability of anxiety. Imaging studies focusing on adolescents' susceptibility to anxiety suggest that the different development trajectories between the limbic system and the executive control system may play important roles in this phenomenon. However, few studies have explored the brain basis of this susceptibility from the perspective of functional networks. The salience network (SN) consists of a series of key limbic and prefrontal r...

  4. —Competitive Brand Salience

    Ralf van der Lans; Rik Pieters; Michel Wedel

    2008-01-01

    Brand salience—the extent to which a brand visually stands out from its competitors—is vital in competing on the shelf, yet is not easy to achieve in practice. This study proposes a methodology to determine the competitive salience of brands, based on a model of visual search and eye-movement recordings collected during a brand search experiment. We estimate brand salience at the point of purchase, based on perceptual features (color, luminance, edges) and how these are influenced by consumer...

  5. Tandospirone, a 5-HT1A partial agonist, ameliorates aberrant lactate production in the prefrontal cortex of rats exposed to blockade of N-methy-D-aspartate receptors; Towards the therapeutics of cognitive impairment of schizophrenia

    Takashi eUehara

    2014-09-01

    Full Text Available Rationale Augmentation therapy with serotonin-1A (5-HT1A receptor partial agonists has been suggested to improve cognitive deficits in patients with schizophrenia. Decreased activity of prefrontal cortex may provide a basis for cognitive deficits of the disease. Lactate plays a significant role in the supply of energy to the brain, and glutamatergic neurotransmission contributes to lactate production.Objectives and methods The purposes of this study were to examine the effect of repeated administration (once a daily for 4 days of tandospirone (0.05 and 5 mg/kg on brain energy metabolism, as represented by extracellular lactate concentration (eLAC in the medial prefrontal cortex (mPFC of young adult rats..Results Four-day treatment with MK-801, an NMDA-R antagonist, prolonged eLAC elevation induced by foot shock stress (FS. Co-administration with the high-dose tandospirone suppressed prolonged FS-induced eLAC elevation in rats receiving MK-801, whereas tandospirone by itself did not affected eLAC increment.Conclusions These results suggest that stimulation of 5-HT1A receptors ameliorates abnormalities of energy metabolism in the mPFC due to blockade of NMDA receptors. These findings provide a possible mechanism based on brain energy metabolism by which 5-HT1A agonism improve cognitive impairment in schizophrenia and related disorders.

  6. Hierarchical Image Saliency Detection on Extended CSSD.

    Shi, Jianping; Yan, Qiong; Xu, Li; Jia, Jiaya

    2016-04-01

    Complex structures commonly exist in natural images. When an image contains small-scale high-contrast patterns either in the background or foreground, saliency detection could be adversely affected, resulting erroneous and non-uniform saliency assignment. The issue forms a fundamental challenge for prior methods. We tackle it from a scale point of view and propose a multi-layer approach to analyze saliency cues. Different from varying patch sizes or downsizing images, we measure region-based scales. The final saliency values are inferred optimally combining all the saliency cues in different scales using hierarchical inference. Through our inference model, single-scale information is selected to obtain a saliency map. Our method improves detection quality on many images that cannot be handled well traditionally. We also construct an extended Complex Scene Saliency Dataset (ECSSD) to include complex but general natural images. PMID:26959676

  7. Tax Complexity, Tax Salience and Tax Politics

    Mumford, Ann

    2015-01-01

    This article considers the implications of the tax salience literature for the United Kingdom. First, the different categories, and definitions, of tax salience that have developed in the literature are reviewed, and some of the prescriptive implications of these terms are introduced. Tax salience refers, essentially, to the capacity of taxpayers to understand legislation. Thus, the potential reasons behind tax complexity and the potential beneficiaries of it are addressed. The article consid...

  8. Increased stress vulnerability after a prefrontal cortex lesion in female rats

    Gerrits, M; Westenbroek, C; Fokkema, DS; Jongsma, ME; Den Boer, JA; Ter Horst, GJ

    2003-01-01

    Neuroimaging studies in patients suffering from affective disorders have shown decreased volume and reduced regional cerebral blood flow in multiple areas of the prefrontal cortex, including the medial prefrontal cortex and the orbitofrontal cortex. This aberrant brain activity is among other things

  9. Spatiochromatic Context Modeling for Color Saliency Analysis.

    Zhang, Jun; Wang, Meng; Zhang, Shengping; Li, Xuelong; Wu, Xindong

    2016-06-01

    Visual saliency is one of the most noteworthy perceptual abilities of human vision. Recent progress in cognitive psychology suggests that: 1) visual saliency analysis is mainly completed by the bottom-up mechanism consisting of feedforward low-level processing in primary visual cortex (area V1) and 2) color interacts with spatial cues and is influenced by the neighborhood context, and thus it plays an important role in a visual saliency analysis. From a computational perspective, the most existing saliency modeling approaches exploit multiple independent visual cues, irrespective of their interactions (or are not computed explicitly), and ignore contextual influences induced by neighboring colors. In addition, the use of color is often underestimated in the visual saliency analysis. In this paper, we propose a simple yet effective color saliency model that considers color as the only visual cue and mimics the color processing in V1. Our approach uses region-/boundary-defined color features with spatiochromatic filtering by considering local color-orientation interactions, therefore captures homogeneous color elements, subtle textures within the object and the overall salient object from the color image. To account for color contextual influences, we present a divisive normalization method for chromatic stimuli through the pooling of contrary/complementary color units. We further define a color perceptual metric over the entire scene to produce saliency maps for color regions and color boundaries individually. These maps are finally globally integrated into a one single saliency map. The final saliency map is produced by Gaussian blurring for robustness. We evaluate the proposed method on both synthetic stimuli and several benchmark saliency data sets from the visual saliency analysis to salient object detection. The experimental results demonstrate that the use of color as a unique visual cue achieves competitive results on par with or better than 12 state

  10. Tax Salience, Voting, and Deliberation

    Sausgruber, Rupert; Tyran, Jean-Robert

    Tax incentives can be more or less salient, i.e. noticeable or cognitively easy to process. Our hypothesis is that taxes on consumers are more salient to consumers than equivalent taxes on sellers because consumers underestimate the extent of tax shifting in the market. We show that tax salience...... biases consumers' voting on tax regimes, and that experience is an effective de-biasing mechanism in the experimental laboratory. Pre-vote deliberation makes initially held opinions more extreme rather than correct and does not eliminate the bias in the typical committee. Yet, if voters can discuss their...... experience with the tax regimes they are less likely to be biased....

  11. Stakeholder salience in humanitarian supply chain management

    Schiffling, Sarah

    2013-01-01

    Mitchell et al.(1997) developed a framework for assessing the salience of stakeholder groups based on their power, urgency and the legitimacy of their claim. This has been applied to illustrate the complexities of stakeholder interactions in humanitarian supply chains and to provide insights for their management and further research. Keywords: Supply chain management, Humanitarian logistics, Stakeholder salience

  12. Regional principal color based saliency detection.

    Lou, Jing; Ren, Mingwu; Wang, Huan

    2014-01-01

    Saliency detection is widely used in many visual applications like image segmentation, object recognition and classification. In this paper, we will introduce a new method to detect salient objects in natural images. The approach is based on a regional principal color contrast modal, which incorporates low-level and medium-level visual cues. The method allows a simple computation of color features and two categories of spatial relationships to a saliency map, achieving higher F-measure rates. At the same time, we present an interpolation approach to evaluate resulting curves, and analyze parameters selection. Our method enables the effective computation of arbitrary resolution images. Experimental results on a saliency database show that our approach produces high quality saliency maps and performs favorably against ten saliency detection algorithms. PMID:25379960

  13. Optical Aberrations and Wavefront

    Nihat Polat

    2014-08-01

    Full Text Available The deviation of light to create normal retinal image in the optical system is called aberration. Aberrations are divided two subgroup: low-order aberrations (defocus: spherical and cylindrical refractive errors and high-order aberrations (coma, spherical, trefoil, tetrafoil, quadrifoil, pentafoil, secondary astigmatism. Aberrations increase with aging. Spherical aberrations are compensated by positive corneal and negative lenticular spherical aberrations in youth. Total aberrations are elevated by positive corneal and positive lenticular spherical aberrations in elderly. In this study, we aimed to analyze the basic terms regarding optic aberrations which have gained significance recently. (Turk J Ophthalmol 2014; 44: 306-11

  14. Quantifying object salience by equating distractor effects

    Huang, L Q; Pashler, Harold

    2005-01-01

    It is commonly believed that objects viewed in certain contexts may be more or less salient. Measurements of salience have usually relied on asking observers "How much does this object stand out against the background?". In this study, we measured the salience of objects by assessing the distraction they produce for subjects searching for a different, pre-specified target. Distraction was measured through response times, but changes in response times were not assumed to be a linear measure of...

  15. Formal Modelling of Salience and Cognitive Load

    Rukšenas, R.; Curzon, P.; Back, J.; Blandford, A.

    2008-01-01

    Well-designed interfaces use procedural and sensory cues to increase the salience of appropriate actions and intentions. However, empirical studies suggest that cognitive load can influence the strength of procedural and sensory cues. We formalise the relationship between salience and cognitive load revealed by empirical data. We add these rules to our abstract cognitive architecture developed for the verification of usability properties. The interface of a fire engine dispatch task used in t...

  16. Discrimination learning with variable stimulus 'salience'

    2011-01-01

    Background In nature, sensory stimuli are organized in heterogeneous combinations. Salient items from these combinations 'stand-out' from their surroundings and determine what and how we learn. Yet, the relationship between varying stimulus salience and discrimination learning remains unclear. Presentation of the hypothesis A rigorous formulation of the problem of discrimination learning should account for varying salience effects. We hypothesize that structural variations in the environment ...

  17. MPEG-4 AVC saliency map computation

    Ammar, M.; Mitrea, M.; Hasnaoui, M.

    2014-02-01

    A saliency map provides information about the regions inside some visual content (image, video, ...) at which a human observer will spontaneously look at. For saliency maps computation, current research studies consider the uncompressed (pixel) representation of the visual content and extract various types of information (intensity, color, orientation, motion energy) which are then fusioned. This paper goes one step further and computes the saliency map directly from the MPEG-4 AVC stream syntax elements with minimal decoding operations. In this respect, an a-priori in-depth study on the MPEG-4 AVC syntax elements is first carried out so as to identify the entities appealing the visual attention. Secondly, the MPEG-4 AVC reference software is completed with software tools allowing the parsing of these elements and their subsequent usage in objective benchmarking experiments. This way, it is demonstrated that an MPEG-4 saliency map can be given by a combination of static saliency and motion maps. This saliency map is experimentally validated under a robust watermarking framework. When included in an m-QIM (multiple symbols Quantization Index Modulation) insertion method, PSNR average gains of 2.43 dB, 2.15dB, and 2.37 dB are obtained for data payload of 10, 20 and 30 watermarked blocks per I frame, i.e. about 30, 60, and 90 bits/second, respectively. These quantitative results are obtained out of processing 2 hours of heterogeneous video content.

  18. A Local Texture-Based Superpixel Feature Coding for Saliency Detection Combined with Global Saliency

    Bingfei Nan

    2015-12-01

    Full Text Available Because saliency can be used as the prior knowledge of image content, saliency detection has been an active research area in image segmentation, object detection, image semantic understanding and other relevant image-based applications. In the case of saliency detection from cluster scenes, the salient object/region detected needs to not only be distinguished clearly from the background, but, preferably, to also be informative in terms of complete contour and local texture details to facilitate the successive processing. In this paper, a Local Texture-based Region Sparse Histogram (LTRSH model is proposed for saliency detection from cluster scenes. This model uses a combination of local texture patterns and color distribution as well as contour information to encode the superpixels to characterize the local feature of image for region contrast computing. Combining the region contrast as computed with the global saliency probability, a full-resolution salient map, in which the salient object/region detected adheres more closely to its inherent feature, is obtained on the bases of the corresponding high-level saliency spatial distribution as well as on the pixel-level saliency enhancement. Quantitative comparisons with five state-of-the-art saliency detection methods on benchmark datasets are carried out, and the comparative results show that the method we propose improves the detection performance in terms of corresponding measurements.

  19. Dysfunction of the prefrontal cortex in addiction: neuroimaging findings and clinical implications

    Goldstein, Rita Z.; Volkow, Nora D

    2011-01-01

    The loss of control over drug intake that occurs in addiction was initially believed to result from disruption of subcortical reward circuits. However, imaging studies in addictive behaviours have identified a key involvement of the prefrontal cortex (PFC) both through its regulation of limbic reward regions and its involvement in higher-order executive function (for example, self-control, salience attribution and awareness). This Review focuses on functional neuroimaging studies conducted in...

  20. Aposematism: balancing salience and camouflage.

    Barnett, James B; Scott-Samuel, Nicholas E; Cuthill, Innes C

    2016-08-01

    Aposematic signals are often characterized by high conspicuousness. Larger and brighter signals reinforce avoidance learning, distinguish defended from palatable prey and are more easily memorized by predators. Conspicuous signalling, however, has costs: encounter rates with naive, specialized or nutritionally stressed predators are likely to increase. It has been suggested that intermediate levels of aposematic conspicuousness can evolve to balance deterrence and detectability, especially for moderately defended species. The effectiveness of such signals, however, has not yet been experimentally tested under field conditions. We used dough caterpillar-like baits to test whether reduced levels of aposematic conspicuousness can have survival benefits when predated by wild birds in natural conditions. Our results suggest that, when controlling for the number and intensity of internal contrast boundaries (stripes), a reduced-conspicuousness aposematic pattern can have a survival advantage over more conspicuous signals, as well as cryptic colours. Furthermore, we find a survival benefit from the addition of internal contrast for both high and low levels of conspicuousness. This adds ecological validity to evolutionary models of aposematic saliency and the evolution of honest signalling. PMID:27484645

  1. Prefrontal cortex and social cognition in mouse and man

    Lucy King Bicks

    2015-11-01

    Full Text Available Social cognition is a complex process that requires the integration of a wide variety of behaviors, including salience, reward-seeking, motivation, knowledge of self and others, and flexibly adjusting behavior in social groups. Not surprisingly, social cognition represents a sensitive domain commonly disrupted in the pathology of a variety of psychiatric disorders including Autism Spectrum Disorder (ASD and Schizophrenia (SCZ. Here, we discuss convergent research from animal models to human disease that implicates the prefrontal cortex (PFC as a key regulator in social cognition, suggesting that disruptions in prefrontal microcircuitry play an essential role in the pathophysiology of psychiatric disorders with shared social deficits. We take a translational perspective of social cognition, and review three key behaviors that are essential to normal social processing in rodents and humans, including social motivation, social recognition, and dominance hierarchy. A shared prefrontal circuitry may underlie these behaviors. Social cognition deficits in animal models of neurodevelopmental disorders like ASD and SCZ have been linked to an altered balance of excitation and inhibition (E/I ratio within the cortex generally, and PFC specifically. A clear picture of the mechanisms by which altered E/I ratio in the PFC might lead to disruptions of social cognition across a variety of behaviors is not well understood. Future studies should explore how disrupted developmental trajectory of prefrontal microcircuitry could lead to altered E/I balance and subsequent deficits in the social domain

  2. Reward salience and risk aversion underlie differential ACC activity in substance dependence

    William H. Alexander

    2015-01-01

    Full Text Available The medial prefrontal cortex, especially the dorsal anterior cingulate cortex (ACC, has long been implicated in cognitive control and error processing. Although the association between ACC and behavior has been established, it is less clear how ACC contributes to dysfunctional behavior such as substance dependence. Evidence from neuroimaging studies investigating ACC function in substance users is mixed, with some studies showing disengagement of ACC in substance dependent individuals (SDs, while others show increased ACC activity related to substance use. In this study, we investigate ACC function in SDs and healthy individuals performing a change signal task for monetary rewards. Using a priori predictions derived from a recent computational model of ACC, we find that ACC activity differs between SDs and controls in factors related to reward salience and risk aversion between SDs and healthy individuals. Quantitative fits of a computational model to fMRI data reveal significant differences in best fit parameters for reward salience and risk preferences. Specifically, the ACC in SDs shows greater risk aversion, defined as concavity in the utility function, and greater attention to rewards relative to reward omission. Furthermore, across participants risk aversion and reward salience are positively correlated. The results clarify the role that ACC plays in both the reduced sensitivity to omitted rewards and greater reward valuation in SDs. Clinical implications of applying computational modeling in psychiatry are also discussed.

  3. On an elementary definition of visual saliency

    Loog, Marco

    2008-01-01

    Various approaches to computational modelling of bottom-up visual attention have been proposed in the past two decades. As part of this trend, researchers have studied ways to characterize the saliency map underlying many of these models. In more recent years, several definitions based on...... probabilistic and information or decision theoretic considerations have been proposed. These provide experimentally successful, appealing, low-level, operational, and elementary definitions of visual saliency (see eg, Bruce, 2005 Neurocomputing 65 125 - 133). Here, I demonstrate that, in fact, all these...

  4. Saliency computation via whitened frequency band selection.

    Lv, Qi; Wang, Bin; Zhang, Liming

    2016-06-01

    Many saliency computational models have been proposed to simulate bottom-up visual attention mechanism of human visual system. However, most of them only deal with certain kinds of images or aim at specific applications. In fact, human beings have the ability to correctly select attentive focuses of objects with arbitrary sizes within any scenes. This paper proposes a new bottom-up computational model from the perspective of frequency domain based on the biological discovery of non-Classical Receptive Field (nCRF) in the retina. A saliency map can be obtained according to the idea of Extended Classical Receptive Field. The model is composed of three major steps: firstly decompose the input image into several feature maps representing different frequency bands that cover the whole frequency domain by utilizing Gabor wavelet. Secondly, whiten the feature maps to highlight the embedded saliency information. Thirdly, select some optimal maps, simulating the response of receptive field especially nCRF, to generate the saliency map. Experimental results show that the proposed algorithm is able to work with stable effect and outstanding performance in a variety of situations as human beings do and is adaptive to both psychological patterns and natural images. Beyond that, biological plausibility of nCRF and Gabor wavelet transform make this approach reliable. PMID:27275381

  5. Referent Salience Affects Second Language Article Use

    Trenkic, Danijela; Pongpairoj, Nattama

    2013-01-01

    The effect of referent salience on second language (L2) article production in real time was explored. Thai (-articles) and French (+articles) learners of English described dynamic events involving two referents, one visually cued to be more salient at the point of utterance formulation. Definiteness marking was made communicatively redundant with…

  6. Visualization of neural networks using saliency maps

    Mørch, Niels J.S.; Kjems, Ulrik; Hansen, Lars Kai;

    1995-01-01

    The saliency map is proposed as a new method for understanding and visualizing the nonlinearities embedded in feedforward neural networks, with emphasis on the ill-posed case, where the dimensionality of the input-field by far exceeds the number of examples. Several levels of approximations are...

  7. Regulating prefrontal cortex activation

    Aznar, Susana; Klein, Anders Bue

    2013-01-01

    The prefrontal cortex (PFC) is involved in mediating important higher-order cognitive processes such as decision making, prompting thereby our actions. At the same time, PFC activation is strongly influenced by emotional reactions through its functional interaction with the amygdala and the stria...

  8. Saliency detection for videos using 3D FFT local spectra

    Long, Zhiling; AlRegib, Ghassan

    2015-03-01

    Bottom-up spatio-temporal saliency detection identifies perceptually important regions of interest in video sequences. The center-surround model proves to be useful for visual saliency detection. In this work, we explore using 3D FFT local spectra as features for saliency detection within the center-surround framework. We develop a spectral location based decomposition scheme to divide a 3D FFT cube into two components, one related to temporal changes and the other related to spatial changes. Temporal saliency and spatial saliency are detected separately using features derived from each spectral component through a simple center-surround comparison method. The two detection results are then combined to yield a saliency map. We apply the same detection algorithm to different color channels (YIQ) and incorporate the results into the final saliency determination. The proposed technique is tested with the public CRCNS database. Both visual and numerical evaluations verify the promising performance of our technique.

  9. Fast full resolution saliency detection based on incoherent imaging system

    Lin, Guang; Zhao, Jufeng; Feng, Huajun; Xu, Zhihai; Li, Qi; Chen, Yueting

    2016-05-01

    Image saliency detection is widely applied in many tasks in the field of the computer vision. In this paper, we combine the saliency detection with the Fourier optics to achieve acceleration of saliency detection algorithm. An actual optical saliency detection system is constructed within the framework of incoherent imaging system. Additionally, the application of our system to implement the bottom-up rapid pre-saliency process of primate visual saliency is discussed with dual-resolution camera. A set of experiments over our system are conducted and discussed. We also demonstrate the comparisons between our method and pure computer methods. The results show our system can produce full resolution saliency maps faster and more effective.

  10. Shifted intrinsic connectivity of central executive and salience network in borderline personality disorder

    Anselm eDoll

    2013-10-01

    Full Text Available Borderline personality disorder (BPD is characterized by stable instability of emotions and behavior and their regulation. This emotional and behavioral instability corresponds with a neurocognitive triple network model of psychopathology, which suggests that aberrant emotional saliency and cognitive control is associated with aberrant interaction across three intrinsic connectivity networks (ICN (i.e. the salience, default mode, and central executive network, SN, DMN, CEN. The objective of the current study was to investigate whether and how such triple network intrinsic functional connectivity (iFC is changed in patients with BPD. We acquired resting-state functional magnetic resonance imaging (rs-fMRI data from fourteen patients with BPD and sixteen healthy controls (HC. High-model order independent component analysis (ICA was used to extract spatiotemporal patterns of ongoing, coherent blood-oxygen-level-dependent (BOLD signal fluctuations from rs-fMRI data. Main outcome measures were iFC within networks (intra-iFC and between networks (i.e. network time course correlation inter-iFC.Aberrant intra-iFC was found in patients’ DMN, SN, and CEN, consistent with previous findings. While patients’ inter-iFC of the CEN was decreased, inter-iFC of the SN was increased. In particular, a balance index reflecting the relationship of CEN-and SN-inter-iFC across networks was strongly shifted from CEN to SN connectivity in patients. Results provide first preliminary evidence for aberrant triple network intrinsic functional connectivity in BPD. Our data suggest a shift of inter-network iFC from networks involved in cognitive control to those of emotion-related activity in BPD, potentially reflecting the persistent instability of emotion regulation in patients.

  11. Fused methods for visual saliency estimation

    Danko, Amanda S.; Lyu, Siwei

    2015-02-01

    In this work, we present a new model of visual saliency by combing results from existing methods, improving upon their performance and accuracy. By fusing pre-attentive and context-aware methods, we highlight the abilities of state-of-the-art models while compensating for their deficiencies. We put this theory to the test in a series of experiments, comparatively evaluating the visual saliency maps and employing them for content-based image retrieval and thumbnail generation. We find that on average our model yields definitive improvements upon recall and f-measure metrics with comparable precisions. In addition, we find that all image searches using our fused method return more correct images and additionally rank them higher than the searches using the original methods alone.

  12. Olfaction spontaneously highlights visual saliency map

    Chen, Kepu; Zhou, Bin; Chen, Shan; He, Sheng; Zhou, Wen

    2013-01-01

    Attention is intrinsic to our perceptual representations of sensory inputs. Best characterized in the visual domain, it is typically depicted as a spotlight moving over a saliency map that topographically encodes strengths of visual features and feedback modulations over the visual scene. By introducing smells to two well-established attentional paradigms, the dot-probe and the visual-search paradigms, we find that a smell reflexively directs attention to the congruent visual image and facili...

  13. Towards three-dimensional visual saliency

    Sharma, Puneet

    2014-01-01

    A salient image region is defined as an image part that is clearly different from its surround in terms of a number of attributes. In bottom-up processing, these attributes are defined as: contrast, color difference, brightness, and orientation. By measuring these attributes, visual saliency algorithms aim to predict the regions in an image that would attract our attention under free viewing conditions, i.e., when the observer is viewing an image without a specific task such as searching for ...

  14. Adaptive Metric Learning for Saliency Detection.

    Li, Shuang; Lu, Huchuan; Lin, Zhe; Shen, Xiaohui; Price, Brian

    2015-11-01

    In this paper, we propose a novel adaptive metric learning algorithm (AML) for visual saliency detection. A key observation is that the saliency of a superpixel can be estimated by the distance from the most certain foreground and background seeds. Instead of measuring distance on the Euclidean space, we present a learning method based on two complementary Mahalanobis distance metrics: 1) generic metric learning (GML) and 2) specific metric learning (SML). GML aims at the global distribution of the whole training set, while SML considers the specific structure of a single image. Considering that multiple similarity measures from different views may enhance the relevant information and alleviate the irrelevant one, we try to fuse the GML and SML together and experimentally find the combining result does work well. Different from the most existing methods which are directly based on low-level features, we devise a superpixelwise Fisher vector coding approach to better distinguish salient objects from the background. We also propose an accurate seeds selection mechanism and exploit contextual and multiscale information when constructing the final saliency map. Experimental results on various image sets show that the proposed AML performs favorably against the state-of-the-arts. PMID:26054067

  15. DISC: Deep Image Saliency Computing via Progressive Representation Learning.

    Chen, Tianshui; Lin, Liang; Liu, Lingbo; Luo, Xiaonan; Li, Xuelong

    2016-06-01

    Salient object detection increasingly receives attention as an important component or step in several pattern recognition and image processing tasks. Although a variety of powerful saliency models have been intensively proposed, they usually involve heavy feature (or model) engineering based on priors (or assumptions) about the properties of objects and backgrounds. Inspired by the effectiveness of recently developed feature learning, we provide a novel deep image saliency computing (DISC) framework for fine-grained image saliency computing. In particular, we model the image saliency from both the coarse-and fine-level observations, and utilize the deep convolutional neural network (CNN) to learn the saliency representation in a progressive manner. In particular, our saliency model is built upon two stacked CNNs. The first CNN generates a coarse-level saliency map by taking the overall image as the input, roughly identifying saliency regions in the global context. Furthermore, we integrate superpixel-based local context information in the first CNN to refine the coarse-level saliency map. Guided by the coarse saliency map, the second CNN focuses on the local context to produce fine-grained and accurate saliency map while preserving object details. For a testing image, the two CNNs collaboratively conduct the saliency computing in one shot. Our DISC framework is capable of uniformly highlighting the objects of interest from complex background while preserving well object details. Extensive experiments on several standard benchmarks suggest that DISC outperforms other state-of-the-art methods and it also generalizes well across data sets without additional training. The executable version of DISC is available online: http://vision.sysu.edu.cn/projects/DISC. PMID:26742147

  16. Visual saliency computations: mechanisms, constraints, and the effect of feedback.

    Soltani, Alireza; Koch, Christof

    2010-09-22

    The primate visual system continuously selects spatial proscribed regions, features or objects for further processing. These selection mechanisms--collectively termed selective visual attention--are guided by intrinsic, bottom-up and by task-dependent, top-down signals. While much psychophysical research has shown that overt and covert attention is partially allocated based on saliency-driven exogenous signals, it is unclear how this is accomplished at the neuronal level. Recent electrophysiological experiments in monkeys point to the gradual emergence of saliency signals when ascending the dorsal visual stream and to the influence of top-down attention on these signals. To elucidate the neural mechanisms underlying these observations, we construct a biologically plausible network of spiking neurons to simulate the formation of saliency signals in different cortical areas. We find that saliency signals are rapidly generated through lateral excitation and inhibition in successive layers of neural populations selective to a single feature. These signals can be improved by feedback from a higher cortical area that represents a saliency map. In addition, we show how top-down attention can affect the saliency signals by disrupting this feedback through its action on the saliency map. While we find that saliency computations require dominant slow NMDA currents, the signal rapidly emerges from successive regions of the network. In conclusion, using a detailed spiking network model we find biophysical mechanisms and limitations of saliency computations which can be tested experimentally. PMID:20861387

  17. A visual saliency based method for vehicle logo detection

    Zhang, Fan; Shen, Yiping; Chang, Hongxing

    2013-07-01

    This paper presents a novel method based on visual saliency and template matching for detecting vehicle logo from images captured by cross-road cameras. To detect the logo, such method first generates a saliency map based on the modified Itti's saliency model, and then obtains regions of interest (ROI) by thresholding the saliency map, at last performs an edge-based template matching to locate the logo. Experiments on more than 2400 images validate both high accuracy and efficiency of the proposed method, and demonstrates our method suitable for real-time application.

  18. Salience Effects in the North-West of England

    Sandra Jansen

    2014-01-01

    The question of how we can define salience, what properties it includes and how we can quantify it have been discussed widely over the past thirty years but we still have more questions than answers about this phenomenon, e. g. not only how salience arises, but also how we can define it. However, despite the lack of a clear definition, salience is often taken into account as an explanatory factor in language change. The scientific discourse on salience has in most cases revolved around phonet...

  19. Aberration Corrected Emittance Exchange

    Nanni, Emilio A

    2015-01-01

    Full exploitation of emittance exchange (EEX) requires aberration-free performance of a complex imaging system including active radio-frequency (RF) elements which can add temporal distortions. We investigate the performance of an EEX line where the exchange occurs between two dimensions with normalized emittances which differ by orders of magnitude. The transverse emittance is exchanged into the longitudinal dimension using a double dog-leg emittance exchange setup with a 5 cell RF deflector cavity. Aberration correction is performed on the four most dominant aberrations. These include temporal aberrations that are corrected with higher order magnetic optical elements located where longitudinal and transverse emittance are coupled. We demonstrate aberration-free performance of emittances differing by 4 orders of magnitude, i.e. an initial transverse emittance of $\\epsilon_x=1$ pm-rad is exchanged with a longitudinal emittance of $\\epsilon_z=10$ nm-rad.

  20. Color edge saliency boosting using natural image statistics

    D. Rojas Vigo; J. van de Weijer; T. Gevers

    2010-01-01

    State of the art methods for image matching, content-based retrieval and recognition use local features. Most of these still exploit only the luminance information for detection. The color saliency boosting algorithm has provided an efficient method to exploit the saliency of color edges based on in

  1. A proto-object-based computational model for visual saliency.

    Yanulevskaya, Victoria; Uijlings, Jasper; Geusebroek, Jan-Mark; Sebe, Nicu; Smeulders, Arnold

    2013-01-01

    State-of-the-art bottom-up saliency models often assign high saliency values at or near high-contrast edges, whereas people tend to look within the regions delineated by those edges, namely the objects. To resolve this inconsistency, in this work we estimate saliency at the level of coherent image regions. According to object-based attention theory, the human brain groups similar pixels into coherent regions, which are called proto-objects. The saliency of these proto-objects is estimated and incorporated together. As usual, attention is given to the most salient image regions. In this paper we employ state-of-the-art computer vision techniques to implement a proto-object-based model for visual attention. Particularly, a hierarchical image segmentation algorithm is used to extract proto-objects. The two most powerful ways to estimate saliency, rarity-based and contrast-based saliency, are generalized to assess the saliency at the proto-object level. The rarity-based saliency assesses if the proto-object contains rare or outstanding details. The contrast-based saliency estimates how much the proto-object differs from the surroundings. However, not all image regions with high contrast to the surroundings attract human attention. We take this into account by distinguishing between external and internal contrast-based saliency. Where the external contrast-based saliency estimates the difference between the proto-object and the rest of the image, the internal contrast-based saliency estimates the complexity of the proto-object itself. We evaluate the performance of the proposed method and its components on two challenging eye-fixation datasets (Judd, Ehinger, Durand, & Torralba, 2009; Subramanian, Katti, Sebe, Kankanhalli, & Chua, 2010). The results show the importance of rarity-based and both external and internal contrast-based saliency in fixation prediction. Moreover, the comparison with state-of-the-art computational models for visual saliency demonstrates the

  2. Improving Saliency Models by Predicting Human Fixation Patches

    Dubey, Rachit

    2015-04-16

    There is growing interest in studying the Human Visual System (HVS) to supplement and improve the performance of computer vision tasks. A major challenge for current visual saliency models is predicting saliency in cluttered scenes (i.e. high false positive rate). In this paper, we propose a fixation patch detector that predicts image patches that contain human fixations with high probability. Our proposed model detects sparse fixation patches with an accuracy of 84 % and eliminates non-fixation patches with an accuracy of 84 % demonstrating that low-level image features can indeed be used to short-list and identify human fixation patches. We then show how these detected fixation patches can be used as saliency priors for popular saliency models, thus, reducing false positives while maintaining true positives. Extensive experimental results show that our proposed approach allows state-of-the-art saliency methods to achieve better prediction performance on benchmark datasets.

  3. Salience Effects in the North-West of England

    Sandra Jansen

    2014-06-01

    Full Text Available The question of how we can define salience, what properties it includes and how we can quantify it have been discussed widely over the past thirty years but we still have more questions than answers about this phenomenon, e. g. not only how salience arises, but also how we can define it. However, despite the lack of a clear definition, salience is often taken into account as an explanatory factor in language change. The scientific discourse on salience has in most cases revolved around phonetic features, while hardly any variables on other linguistic levels have been investigated in terms of their salience. Hence, one goal of this paper is to argue for an expanded view of salience in the sociolinguistic context. This article investigates the variation and change of two groups of variables in Carlisle, an urban speech community in the north west of England. I analyse the variable (th and in particular the replacement of /θ/ with [f] which is widely known as th-fronting. The use of three discourse markers is also examined. Both groups of features will then be discussed in the light of sociolinguistic salience.

  4. MRI volumetry of prefrontal cortex

    Sheline, Yvette I.; Black, Kevin J.; Lin, Daniel Y.; Pimmel, Joseph; Wang, Po; Haller, John W.; Csernansky, John G.; Gado, Mokhtar; Walkup, Ronald K.; Brunsden, Barry S.; Vannier, Michael W.

    1995-05-01

    Prefrontal cortex volumetry by brain magnetic resonance (MR) is required to estimate changes postulated to occur in certain psychiatric and neurologic disorders. A semiautomated method with quantitative characterization of its performance is sought to reliably distinguish small prefrontal cortex volume changes within individuals and between groups. Stereological methods were tested by a blinded comparison of measurements applied to 3D MR scans obtained using an MPRAGE protocol. Fixed grid stereologic methods were used to estimate prefrontal cortex volumes on a graphic workstation, after the images are scaled from 16 to 8 bits using a histogram method. In addition images were resliced into coronal sections perpendicular to the bicommissural plane. Prefrontal cortex volumes were defined as all sections of the frontal lobe anterior to the anterior commissure. Ventricular volumes were excluded. Stereological measurement yielded high repeatability and precision, and was time efficient for the raters. The coefficient of error was depression and schizophrenia can be efficiently assessed using this method.

  5. On the Salience-Based Level-k Model

    Wolff, Irenaeus

    2015-01-01

    In the current literature, there is a lively debate about whether a level-k model can be based on salience to explain behaviour in games with distinctive action labels such as hide-and-seek or discoordination games. This study presents six different experiments designed to measure salience. When based on any of these empirical salience measures, the standard level-k model does not explain hide-and-seek behaviour. Modifying the model such that players followsalience when payoffs are equal, the...

  6. Invariant Spectral Hashing of Image Saliency Graph

    Taquet, Maxime; De Vleeschouwer, Christophe; Macq, Benoit

    2010-01-01

    Image hashing is the process of associating a short vector of bits to an image. The resulting summaries are useful in many applications including image indexing, image authentication and pattern recognition. These hashes need to be invariant under transformations of the image that result in similar visual content, but should drastically differ for conceptually distinct contents. This paper proposes an image hashing method that is invariant under rotation, scaling and translation of the image. The gist of our approach relies on the geometric characterization of salient point distribution in the image. This is achieved by the definition of a "saliency graph" connecting these points jointly with an image intensity function on the graph nodes. An invariant hash is then obtained by considering the spectrum of this function in the eigenvector basis of the Laplacian graph, that is, its graph Fourier transform. Interestingly, this spectrum is invariant under any relabeling of the graph nodes. The graph reveals geomet...

  7. Simultaneous modeling of visual saliency and value computation improves predictions of economic choice

    Towal, R. Blythe; Mormann, Milica; Koch, Christof

    2013-01-01

    Many decisions we make require visually identifying and evaluating numerous alternatives quickly. These usually vary in reward, or value, and in low-level visual properties, such as saliency. Both saliency and value influence the final decision. In particular, saliency affects fixation locations and durations, which are predictive of choices. However, it is unknown how saliency propagates to the final decision. Moreover, the relative influence of saliency and value is unclear. Here we address...

  8. A ventral salience network in the macaque brain.

    Touroutoglou, Alexandra; Bliss-Moreau, Eliza; Zhang, Jiahe; Mantini, Dante; Vanduffel, Wim; Dickerson, Bradford C; Barrett, Lisa Feldman

    2016-05-15

    Successful navigation of the environment requires attending and responding efficiently to objects and conspecifics with the potential to benefit or harm (i.e., that have value). In humans, this function is subserved by a distributed large-scale neural network called the "salience network". We have recently demonstrated that there are two anatomically and functionally dissociable salience networks anchored in the dorsal and ventral portions of the human anterior insula (Touroutoglou et al., 2012). In this paper, we test the hypothesis that these two subnetworks exist in rhesus macaques (Macaca mulatta). We provide evidence that a homologous ventral salience network exists in macaques, but that the connectivity of the dorsal anterior insula in macaques is not sufficiently developed as a dorsal salience network. The evolutionary implications of these finding are considered. PMID:26899785

  9. Diversification of visual media retrieval results using saliency detection

    Muratov, Oleg; Boato, Giulia; De Natale, Franesco G. B.

    2013-03-01

    Diversification of retrieval results allows for better and faster search. Recently there has been proposed different methods for diversification of image retrieval results mainly utilizing text information and techniques imported from natural language processing domain. However, images contain visual information that is impossible to describe in text and the use of visual features is inevitable. Visual saliency is information about the main object of an image implicitly included by humans while creating visual content. For this reason it is naturally to exploit this information for the task of diversification of the content. In this work we study whether visual saliency can be used for the task of diversification and propose a method for re-ranking image retrieval results using saliency. The evaluation has shown that the use of saliency information results in higher diversity of retrieval results.

  10. Mortality salience increases personal relevance of the norm of reciprocity.

    Schindler, Simon; Reinhard, Marc-André; Stahlberg, Dagmar

    2012-10-01

    Research on terror management theory found evidence that people under mortality salience strive to live up to salient cultural norms and values, like egalitarianism, pacifism, or helpfulness. A basic, strongly internalized norm in most human societies is the norm of reciprocity: people should support those who supported them (i.e., positive reciprocity), and people should injure those who injured them (i.e., negative reciprocity), respectively. In an experiment (N = 98; 47 women, 51 men), mortality salience overall significantly increased personal relevance of the norm of reciprocity (M = 4.45, SD = 0.65) compared to a control condition (M = 4.19, SD = 0.59). Specifically, under mortality salience there was higher motivation to punish those who treated them unfavourably (negative norm of reciprocity). Unexpectedly, relevance of the norm of positive reciprocity remained unaffected by mortality salience. Implications and limitations are discussed. PMID:23234099

  11. Saliency-Based Fidelity Adaptation Preprocessing for Video Coding

    Shao-Ping Lu; Song-Hai Zhang

    2011-01-01

    In this paper, we present a video coding scheme which applies the technique of visual saliency computation to adjust image fidelity before compression. To extract visually salient features, we construct a spatio-temporal saliency map by analyzing the video using a combined bottom-up and top-down visual saliency model. We then use an extended bilateral filter, in which the local intensity and spatial scales are adjusted according to visual saliency, to adaptively alter the image fidelity. Our implementation is based on the H.264 video encoder JM12.0. Besides evaluating our scheme with the H.264 reference software, we also compare it to a more traditional foreground-background segmentation-based method and a foveation-based approach which employs Gaussian blurring. Our results show that the proposed algorithm can improve the compression ratio significantly while effectively preserving perceptual visual quality.

  12. Multi-scale saliency search in image analysis.

    Slepoy, Alexander; Campisi, Anthony; Backer, Alejandro

    2005-10-01

    Saliency detection in images is an important outstanding problem both in machine vision design and the understanding of human vision mechanisms. Recently, seminal work by Itti and Koch resulted in an effective saliency-detection algorithm. We reproduce the original algorithm in a software application Vision and explore its limitations. We propose extensions to the algorithm that promise to improve performance in the case of difficult-to-detect objects.

  13. Modelling Saliency Awareness for Objective Video Quality Assessment

    Engelke, Ulrich; Barkowsky, Marcus; Callet, Patrick Le; Zepernick, Hans-Jürgen

    2010-01-01

    Existing video quality metrics do usually not take into consideration that spatial regions in video frames are of varying saliency and thus, differently attract the viewer's attention. This paper proposes a model of saliency awareness to complement existing video quality metrics, with the aim to improve the agreement of objectively predicted quality with subjectively rated quality. For this purpose, we conducted a subjective experiment in which human observers rated the annoyance of vide...

  14. Visually guided pointing movements are driven by the salience map.

    Zehetleitner, Michael; Hegenloh, Michael; Müller, Hermann J

    2011-01-01

    Visual salience maps are assumed to mediate target selection decisions in a motor-unspecific manner; accordingly, modulations of salience influence yes/no target detection or left/right localization responses in manual key-press search tasks, as well as ocular or skeletal movements to the target. Although widely accepted, this core assumption is based on little psychophysical evidence. At least four modulations of salience are known to influence the speed of visual search for feature singletons: (i) feature contrast, (ii) cross-trial dimension sequence and (iii) semantic pre-cueing of the target dimension, and (iv) dimensional target redundancy. If salience guides also manual pointing movements, their initiation latencies (and durations) should be affected by the same four manipulations of salience. Four experiments, each examining one of these manipulations, revealed this to be the case. Thus, these effects are seen independently of the motor response required to signal the perceptual decision (e.g., directed manual pointing as well as simple yes/no detection responses). This supports the notion of a motor-unspecific salience map, which guides covert attention as well as overt eye and hand movements. PMID:21282341

  15. Spectral saliency via automatic adaptive amplitude spectrum analysis

    Wang, Xiaodong; Dai, Jialun; Zhu, Yafei; Zheng, Haiyong; Qiao, Xiaoyan

    2016-03-01

    Suppressing nonsalient patterns by smoothing the amplitude spectrum at an appropriate scale has been shown to effectively detect the visual saliency in the frequency domain. Different filter scales are required for different types of salient objects. We observe that the optimal scale for smoothing amplitude spectrum shares a specific relation with the size of the salient region. Based on this observation and the bottom-up saliency detection characterized by spectrum scale-space analysis for natural images, we propose to detect visual saliency, especially with salient objects of different sizes and locations via automatic adaptive amplitude spectrum analysis. We not only provide a new criterion for automatic optimal scale selection but also reserve the saliency maps corresponding to different salient objects with meaningful saliency information by adaptive weighted combination. The performance of quantitative and qualitative comparisons is evaluated by three different kinds of metrics on the four most widely used datasets and one up-to-date large-scale dataset. The experimental results validate that our method outperforms the existing state-of-the-art saliency models for predicting human eye fixations in terms of accuracy and robustness.

  16. Disgust sensitivity predicts defensive responding to mortality salience.

    Kelley, Nicholas J; Crowell, Adrienne L; Tang, David; Harmon-Jones, Eddie; Schmeichel, Brandon J

    2015-10-01

    Disgust protects the physical self. The present authors suggest that disgust also contributes to the protection of the psychological self by fostering stronger defensive reactions to existential concerns. To test this idea, 3 studies examined the link between disgust sensitivity and defensive responses to mortality salience or "terror management" processes (Greenberg, Solomon, & Pyszczynski, 1997). Each study included an individual difference measure of disgust sensitivity, a manipulation of mortality salience, and a dependent measure of defensive responding. In Study 1, disgust sensitivity predicted increases in worldview defense in the mortality salience condition but not in the control condition. In Study 2, disgust sensitivity predicted increases in optimistic perceptions of the future in the mortality salience condition but not in the control condition. In Study 3, disgust sensitivity predicted reductions in delay discounting for those in the mortality salience condition such that those higher in disgust sensitivity discounted the future less. This pattern did not occur in the control condition. These findings highlight disgust sensitivity as a key to understanding reactions to mortality salience, and they support the view that disgust-related responses protect against both physical (e.g., noxious substances) and psychological threats. PMID:25775230

  17. Learning a Combined Model of Visual Saliency for Fixation Prediction.

    Wang, Jingwei; Borji, Ali; Jay Kuo, C-C; Itti, Laurent

    2016-04-01

    A large number of saliency models, each based on a different hypothesis, have been proposed over the past 20 years. In practice, while subscribing to one hypothesis or computational principle makes a model that performs well on some types of images, it hinders the general performance of a model on arbitrary images and large-scale data sets. One natural approach to improve overall saliency detection accuracy would then be fusing different types of models. In this paper, inspired by the success of late-fusion strategies in semantic analysis and multi-modal biometrics, we propose to fuse the state-of-the-art saliency models at the score level in a para-boosting learning fashion. First, saliency maps generated by several models are used as confidence scores. Then, these scores are fed into our para-boosting learner (i.e., support vector machine, adaptive boosting, or probability density estimator) to generate the final saliency map. In order to explore the strength of para-boosting learners, traditional transformation-based fusion strategies, such as Sum, Min, and Max, are also explored and compared in this paper. To further reduce the computation cost of fusing too many models, only a few of them are considered in the next step. Experimental results show that score-level fusion outperforms each individual model and can further reduce the performance gap between the current models and the human inter-observer model. PMID:26829792

  18. Visual saliency in MPEG-4 AVC video stream

    Ammar, M.; Mitrea, M.; Hasnaoui, M.; Le Callet, P.

    2015-03-01

    Visual saliency maps already proved their efficiency in a large variety of image/video communication application fields, covering from selective compression and channel coding to watermarking. Such saliency maps are generally based on different visual characteristics (like color, intensity, orientation, motion,…) computed from the pixel representation of the visual content. This paper resumes and extends our previous work devoted to the definition of a saliency map solely extracted from the MPEG-4 AVC stream syntax elements. The MPEG-4 AVC saliency map thus defined is a fusion of static and dynamic map. The static saliency map is in its turn a combination of intensity, color and orientation features maps. Despite the particular way in which all these elementary maps are computed, the fusion techniques allowing their combination plays a critical role in the final result and makes the object of the proposed study. A total of 48 fusion formulas (6 for combining static features and, for each of them, 8 to combine static to dynamic features) are investigated. The performances of the obtained maps are evaluated on a public database organized at IRCCyN, by computing two objective metrics: the Kullback-Leibler divergence and the area under curve.

  19. Fast and Conspicuous? Quantifying Salience With the Theory of Visual Attention

    Krüger, Alexander; Tünnermann, Jan; Scharlau, Ingrid

    2016-01-01

    Particular differences between an object and its surrounding cause salience, guide attention, and improve performance in various tasks. While much research has been dedicated to identifying which feature dimensions contribute to salience, much less regard has been paid to the quantitative strength of the salience caused by feature differences. Only a few studies systematically related salience effects to a common salience measure, and they are partly outdated in the light of new findings on the time course of salience effects. We propose Bundesen’s Theory of Visual Attention (TVA) as a theoretical basis for measuring salience and introduce an empirical and modeling approach to link this theory to data retrieved from temporal-order judgments. With this procedure, TVA becomes applicable to a broad range of salience-related stimulus material. Three experiments with orientation pop-out displays demonstrate the feasibility of the method. A 4th experiment substantiates its applicability to the luminance dimension. PMID:27168868

  20. Attribution and expression of incentive salience are differentially signaled by ultrasonic vocalizations in rats.

    Brenes, Juan C; Schwarting, Rainer K W

    2014-01-01

    During Pavlovian incentive learning, the affective properties of rewards are thought to be transferred to their predicting cues. However, how rewards are represented emotionally in animals is widely unknown. This study sought to determine whether 50-kHz ultrasonic vocalizations (USVs) in rats may signal such a state of incentive motivation to natural, nutritional rewards. To this end, rats learned to anticipate food rewards and, across experiments, the current physiological state (deprived vs. sated), the type of learning mechanism recruited (Pavlovian vs. instrumental), the hedonic properties of UCS (low vs. high palatable food), and the availability of food reward (continued vs. discontinued) were manipulated. Overall, we found that reward-cues elicited 50-kHz calls as they were signaling a putative affective state indicative of incentive motivation in the rat. Attribution and expression of incentive salience, however, seemed not to be an unified process, and could be teased apart in two different ways: 1) under high motivational state (i.e., hunger), the attribution of incentive salience to cues occurred without being expressed at the USVs level, if reward expectations were higher than the outcome; 2) in all experiments when food rewards were devalued by satiation, reward cues were still able to elicit USVs and conditioned anticipatory activity although reward seeking and consumption were drastically weakened. Our results suggest that rats are capable of representing rewards emotionally beyond apparent, immediate physiological demands. These findings may have translational potential in uncovering mechanisms underlying aberrant and persistent motivation as observed in drug addiction, gambling, and eating disorders. PMID:25047234

  1. Attribution and expression of incentive salience are differentially signaled by ultrasonic vocalizations in rats.

    Juan C Brenes

    Full Text Available During Pavlovian incentive learning, the affective properties of rewards are thought to be transferred to their predicting cues. However, how rewards are represented emotionally in animals is widely unknown. This study sought to determine whether 50-kHz ultrasonic vocalizations (USVs in rats may signal such a state of incentive motivation to natural, nutritional rewards. To this end, rats learned to anticipate food rewards and, across experiments, the current physiological state (deprived vs. sated, the type of learning mechanism recruited (Pavlovian vs. instrumental, the hedonic properties of UCS (low vs. high palatable food, and the availability of food reward (continued vs. discontinued were manipulated. Overall, we found that reward-cues elicited 50-kHz calls as they were signaling a putative affective state indicative of incentive motivation in the rat. Attribution and expression of incentive salience, however, seemed not to be an unified process, and could be teased apart in two different ways: 1 under high motivational state (i.e., hunger, the attribution of incentive salience to cues occurred without being expressed at the USVs level, if reward expectations were higher than the outcome; 2 in all experiments when food rewards were devalued by satiation, reward cues were still able to elicit USVs and conditioned anticipatory activity although reward seeking and consumption were drastically weakened. Our results suggest that rats are capable of representing rewards emotionally beyond apparent, immediate physiological demands. These findings may have translational potential in uncovering mechanisms underlying aberrant and persistent motivation as observed in drug addiction, gambling, and eating disorders.

  2. Activation of midbrain and ventral striatal regions implicates salience processing during a modified beads task.

    Christine Esslinger

    Full Text Available INTRODUCTION: Metacognition, i.e. critically reflecting on and monitoring one's own reasoning, has been linked behaviorally to the emergence of delusions and is a focus of cognitive therapy in patients with schizophrenia. However, little is known about the neural processing underlying metacognitive function. To address this issue, we studied brain activity during a modified beads task which has been used to measure a "Jumping to Conclusions" (JTC bias in schizophrenia patients. METHODS: We used functional magnetic resonance imaging to identify neural systems active in twenty-five healthy subjects when solving a modified version of the "beads task", which requires a probabilistic decision after a variable amount of data has been requested by the participants. We assessed brain activation over the duration of a trial and at the time point of decision making. RESULTS: Analysis of activation during the whole process of probabilistic reasoning showed an extended network including the prefronto-parietal executive functioning network as well as medial parieto-occipital regions. During the decision process alone, activity in midbrain and ventral striatum was detected, as well as in thalamus, medial occipital cortex and anterior insula. CONCLUSIONS: Our data show that probabilistic reasoning shares neural substrates with executive functions. In addition, our finding that brain regions commonly associated with salience processing are active during probabilistic reasoning identifies a candidate mechanism that could underlie the behavioral link between dopamine-dependent aberrant salience and JTC in schizophrenia. Further studies with delusional schizophrenia patients will have to be performed to substantiate this link.

  3. The rostral prefrontal cortex underlies individual differences in working memory capacity: An approach from the hierarchical model of the cognitive control.

    Minamoto, Takehiro; Yaoi, Ken; Osaka, Mariko; Osaka, Naoyuki

    2015-10-01

    Neuroimaging and behavioral evidence has suggested that the lateral prefrontal cortex is involved in individual differences in working memory capacity (WMC). However, few studies have localized the neural structures that differentiate high and low WMC individuals, considering the functional architecture of the prefrontal cortex. The present study aimed to identify a frontal region that underlies individual differences from the perspective of the hierarchical architecture of the frontal cortex. By manipulating an episodic factor of cognitive control (control in selecting an appropriate task set according to a temporal context) and using a parametric modulation analysis, we found that both high- and low- WMC individuals have similar activation patterns in the premotor cortex (BA6, 8), caudal prefrontal cortex (BA44, 45), and frontopolar cortex (BA10, 11), but differed in the rostral part of the prefrontal cortex (BA46/47); high WMC individuals showed greater activation in the higher episodic control condition, whereas low WMC individuals showed reduced activation when episodic control was required. Similar patterns of activation were found in the right inferior parietal and middle/inferior temporal cortices. These results indicate that the rostral prefrontal cortex, which supports episodic cognitive control, possibly by sending a weighting signal toward the inferior parietal and middle/inferior temporal cortices that modulate saliency and sensory processing, underlies individual differences in WMC. Episodic control account, which considers the organization of the prefrontal cortex, fits well with previous findings of individual differences in WMC. PMID:26280275

  4. Moving Foreground Detection Based On Spatio-temporal Saliency

    Yang Xia

    2013-01-01

    Full Text Available Detection of moving foreground in video is very important for many applications, such as visual surveillance, object-based video coding, etc. When objects move with different speeds and under illumination changes, the robustness of moving object detection methods proposed so far is still not satisfactory. In this paper, we use the semantic information to adjust the pixel-wise learning rate adaptively for more robust detection performance, which are obtained by spatial saliency map based on Gaussian mixture model (GMM in luma space and temporal saliency map obtained by background subtraction. In addition, we design a two-pass background estimation framework, in which the initial estimation is used for temporal saliency estimation, and the other is to detect foreground and update model parameters. The experimental results show that our method can achieve better moving object extraction performance than the existing background subtraction method based on GMM.

  5. Land Cover Change Detection Using Saliency Andwavelet Transformation

    Zhang, Haopeng; Jiang, Zhiguo; Cheng, Yan

    2016-06-01

    How to obtain accurate difference map remains an open challenge in change detection. To tackle this problem, we propose a change detection method based on saliency detection and wavelet transformation. We do frequency-tuned saliency detection in initial difference image (IDI) obtained by logarithm ratio to get a salient difference image (SDI). Then, we calculate local entropy of SDI to obtain an entropic salient difference image (ESDI). The final difference image (FDI) is the wavelet fusion of IDI and ESDI, and Otsu thresholding is used to extract difference map from FDI. Experimental results validate the effectiveness and feasibility.

  6. Prefrontal Engagement by Cognitive Reappraisal of Negative Faces

    Nelson, Brady D.; Fitzgerald, Daniel A.; Klumpp, Heide; Shankman, Stewart A.; Phan, K. Luan

    2014-01-01

    Cognitive reappraisal has been associated with increased activation in prefrontal cortex (PFC) and cingulate regions implicated in cognitive control and affect regulation. To date, neuroimaging studies of reappraisal have primarily used emotionally evocative scenes, and it remains unclear whether the same cognitive strategy applied to emotional facial expressions would involve similar or different neural underpinnings. The present study used fMRI to examine brain activation during cognitive reappraisal of negatively valenced facial expressions relative to passive viewing of negative and neutral facial expressions. Twenty-two healthy adults completed a cognitive reappraisal task comprised of three different conditions (Look-Neutral, Maintain-Negative, Reappraise-Negative). Results indicated that reappraisal was associated with a decrease in negative affect and engagement of PFC brain regions implicated in cognitive control and affect regulation (DLPFC, mPFC, and VLPFC). Furthermore, individual differences in habitual reappraisal use were associated with greater DLPFC and mPFC activation, while suppression use was associated with greater amygdala activation. The present study provides preliminary evidence that facial expressions are effective alternative ‘targets’ of prefrontal engagement during cognitive reappraisal. These findings are particularly relevant for future research probing the neural bases of emotion regulation in populations for whom aversive scenes may be less appropriate (e.g., children) and illnesses in which aberrant responses to social signals of threat and negative feedback are cardinal phenotypes. PMID:25433095

  7. Aberrations in asymmetrical electron lenses

    Starting from well established knowledge in light-optics we explore the question if electron-optical aberration can be improved in asymmetrical electron lenses. We show that spherical as well as chromatic aberration coefficients are reduced in asymmetric electrostatic einzel lenses when the center electrode is moved away from the center position towards the entrance electrode. Relative improvements up to 40% for both the chromatic and the spherical aberration coefficients can be obtained. We use analytical and numerical calculations to confirm this result for exemplary cases of a lens with fixed length and working distance. The agreement of the two calculation methods is very good. We then derive an estimate for the electron-optical aberration coefficients from light-optics. The derived expressions for chromatic and spherical aberrations are somewhat simpler than the ones derived from electron-optics as they involve integrals only over the electrostatic potential, not over the electron paths. The estimated formulas still agree well with the electron optical calculations. Overall, we are tempted to suggest that the enormous knowledge base of light optics can provide considerable guidance for electron-optical applications. -- Highlights: ► Develops the analogy between light and electron optics in aberration calculations. ► Optimized spherical and chromatic aberrations for an electrostatic einzel lens. ► Comparison between analytic and numerical aberration calculations.

  8. GABA levels in the ventromedial prefrontal cortex during the viewing of appetitive and disgusting food images.

    Padulo, Caterina; Delli Pizzi, Stefano; Bonanni, Laura; Edden, Richard A E; Ferretti, Antonio; Marzoli, Daniele; Franciotti, Raffaella; Manippa, Valerio; Onofrj, Marco; Sepede, Gianna; Tartaro, Armando; Tommasi, Luca; Puglisi-Allegra, Stefano; Brancucci, Alfredo

    2016-10-01

    Characterizing how the brain appraises the psychological dimensions of reward is one of the central topics of neuroscience. It has become clear that dopamine neurons are implicated in the transmission of both rewarding information and aversive and alerting events through two different neuronal populations involved in encoding the motivational value and the motivational salience of stimuli, respectively. Nonetheless, there is less agreement on the role of the ventromedial prefrontal cortex (vmPFC) and the related neurotransmitter release during the processing of biologically relevant stimuli. To address this issue, we employed magnetic resonance spectroscopy (MRS), a non-invasive methodology that allows detection of some metabolites in the human brain in vivo, in order to assess the role of the vmPFC in encoding stimulus value rather than stimulus salience. Specifically, we measured gamma-aminobutyric acid (GABA) and, with control purposes, Glx levels in healthy subjects during the observation of appetitive and disgusting food images. We observed a decrease of GABA and no changes in Glx concentration in the vmPFC in both conditions. Furthermore, a comparatively smaller GABA reduction during the observation of appetitive food images than during the observation of disgusting food images was positively correlated with the scores obtained to the body image concerns sub-scale of Body Uneasiness Test (BUT). These results are consistent with the idea that the vmPFC plays a crucial role in processing both rewarding and aversive stimuli, possibly by encoding stimulus salience through glutamatergic and/or noradrenergic projections to deeper mesencephalic and limbic areas. PMID:27436536

  9. Bilinearity, rules, and prefrontal cortex

    Peter Dayan

    2007-11-01

    Full Text Available Humans can be instructed verbally to perform computationally complex cognitive tasks; their performance then improves relatively slowly over the course of practice. Many skills underlie these abilities; in this paper, we focus on the particular question of a uniform architecture for the instantiation of habitual performance and the storage, recall, and execution of simple rules. Our account builds on models of gated working memory, and involves a bilinear architecture for representing conditional input-output maps and for matching rules to the state of the input and working memory. We demonstrate the performance of our model on two paradigmatic tasks used to investigate prefrontal and basal ganglia function.

  10. Mapping Prefrontal Cortex Functions in Human Infancy

    Grossmann, Tobias

    2013-01-01

    It has long been thought that the prefrontal cortex, as the seat of most higher brain functions, is functionally silent during most of infancy. This review highlights recent work concerned with the precise mapping (localization) of brain activation in human infants, providing evidence that prefrontal cortex exhibits functional activation much…

  11. Of wealth and death: materialism, mortality salience, and consumption behavior.

    Kasser, T; Sheldon, K M

    2000-07-01

    Theoretical work suggests that feelings of insecurity produce materialistic behavior, but most empirical evidence is correlational in nature. We therefore experimentally activated feelings of insecurity by having some subjects write short essays about death (mortality-salience condition). In Study 1, subjects in the mortality-salience condition, compared with subjects who wrote about a neutral topic, had higher financial expectations for themselves 15 years in the future, in terms of both their overall worth and the amount they would be spending on pleasurable items such as clothing and entertainment. Study 2 extended these findings by demonstrating that subjects exposed to death became more greedy and consumed more resources in a forest-management game. Results are discussed with regard to humanistic and terror-management theories of materialism. PMID:11273398

  12. Exploiting Surroundedness for Saliency Detection: A Boolean Map Approach.

    Zhang, Jianming; Sclaroff, Stan

    2016-05-01

    We demonstrate the usefulness of surroundedness for eye fixation prediction by proposing a Boolean Map based Saliency model (BMS). In our formulation, an image is characterized by a set of binary images, which are generated by randomly thresholding the image's feature maps in a whitened feature space. Based on a Gestalt principle of figure-ground segregation, BMS computes a saliency map by discovering surrounded regions via topological analysis of Boolean maps. Furthermore, we draw a connection between BMS and the Minimum Barrier Distance to provide insight into why and how BMS can properly captures the surroundedness cue via Boolean maps. The strength of BMS is verified by its simplicity, efficiency and superior performance compared with 10 state-of-the-art methods on seven eye tracking benchmark datasets. PMID:26336114

  13. Image based Monument Recognition using Graph based Visual Saliency

    Kalliatakis, Grigorios; Triantafyllidis, Georgios

    2013-01-01

    This article presents an image-based application aiming at simple image classification of well-known monuments in the area of Heraklion, Crete, Greece. This classification takes place by utilizing Graph Based Visual Saliency (GBVS) and employing Scale Invariant Feature Transform (SIFT) or Speeded...... images have been previously processed according to the Graph Based Visual Saliency model in order to keep either SIFT or SURF features corresponding to the actual monuments while the background “noise” is minimized. The application is then able to classify these images, helping the user to better...... Up Robust Features (SURF). For this purpose, images taken at various places of interest are being compared to an existing database containing images of these places at different angles and zoom. The time required for the matching progress in such application is an important element. To this goal, the...

  14. Visual Saliency and Attention as Random Walks on Complex Networks

    Costa, L F

    2006-01-01

    The unmatched versatility of vision in mammals is totally dependent on purposive eye movements and selective attention guided by saliencies in the presented images. The current article shows how concepts and tools from the areas of random walks, Markov chains, complex networks and artificial image analysis can be naturally combined in order to provide a unified and biologically plausible model for saliency detection and visual attention, which become indistinguishable in the process. Images are converted into complex networks by considering pixels as nodes while connections are established in terms of fields of influence defined by visual features such as tangent fields induced by luminance contrasts, distance, and size. Random walks are performed on such networks in order to emulate attentional shifts and even eye movements in the case of large shapes, and the frequency of visits to each node is conveniently obtained from the eigenequation defined by the stochastic matrix associated to the respectively drive...

  15. Saliency and eye movements in the perception of natural scenes

    Foulsham, Thomas

    2008-01-01

    Humans inspect the environment around them by selecting a sequence of locations to fixate which will provide information about the scene. How are these locations chosen? The saliency map model suggests that points in the scene are represented topographically and that the likelihood of them being fixated depends on low-level feature contrast. This model makes specific predictions about the way people will move their eyes when looking at natural scenes, although there are few experimental te...

  16. Saliency of product origin information in consumer choices

    Dmitrović, Tanja; Vida, Irena

    2015-01-01

    In light of increasing market complexities resulting from globalization of consumer products/brands in both mature and transitional markets, this study examines the saliency of information related to the national origin of products in consumer choice behavior. Specifically, effects of consumer ethnocentrism and the type of product/service category on perceived importance of product origin information are investigated. Analysis of data collected on a sample of adult consumers suggests that sal...

  17. Saliency extraction with a distributed spiking neural network

    Chevallier, Sylvain; Tarroux, Philippe; Paugam-Moisy, Hélène

    2006-01-01

    We present a distributed spiking neuron network (SNN) for handling low-level visual perception in order to extract salient locations in robot camera images. We describe a new method which reduce the computional load of the whole system, stemming from our choices of architecture. We also describe a modeling of post-synaptic potential, which allows to quickly compute the contribution of a sum of incoming spikes to a neuron's membrane potential. The interests of this saliency extraction method, ...

  18. Visual Saliency Computations: Mechanisms, Constraints, and the Effect of Feedback

    Soltani, Alireza; Koch, Christof

    2010-01-01

    The primate visual system continuously selects spatial proscribed regions, features or objects for further processing. These selection mechanisms—collectively termed selective visual attention—are guided by intrinsic, bottom-up and by task-dependent, top-down signals. While much psychophysical research has shown that overt and covert attention is partially allocated based on saliency-driven exogenous signals, it is unclear how this is accomplished at the neuronal level. Recent electrophysiolo...

  19. Multiview saliency detection based on improved multimanifold ranking

    Shi, Yanjiao; Yi, Yugen; Zhang, Ke; Kong, Jun; Zhang, Ming; Wang, Jianzhong

    2014-11-01

    As an important problem in computer vision, saliency detection is essential for image segmentation, super-resolution, object recognition, and so on. We propose a saliency detection method for images. Instead of using contrast between salient regions and their surrounding areas, both cues from salient and nonsalient regions are considered in our study. Based on these cues, an improved multimanifold ranking algorithm is proposed. In our algorithm, features from multiple views are utilized and the different contributions of these multiview features are taken into account. Moreover, an iterative updating optimization scheme is explored to solve the objective function, during which the feature fusion is performed. After two-stage ranking by the improved multimanifold ranking algorithm, each image patch can be assigned a ranking score, which determines the final saliency. The proposed method is evaluated on four public datasets and is compared with the state-of-the-art methods. Experimental results indicate that the proposed method outperforms existing schemes both in qualitative and quantitative comparisons.

  20. Key Object Discovery and Tracking Based on Context-Aware Saliency

    Geng Zhang

    2013-01-01

    Full Text Available In this paper, we propose an online key object discovery and tracking system based on visual saliency. We formulate the problem as a temporally consistent binary labelling task on a conditional random field and solve it by using a particle filter. We also propose a context‐aware saliency measurement, which can be used to improve the accuracy of any static or dynamic saliency maps. Our refined saliency maps provide clearer indications as to where the key object lies. Based on good saliency cues, we can further segment the key object inside the resulting bounding box, considering the spatial and temporal context. We tested our system extensively on different video clips. The results show that our method has significantly improved the saliency maps and tracks the key object accurately.

  1. Low-Complexity Saliency Detection Algorithm for Fast Perceptual Video Coding

    Pengyu Liu

    2013-01-01

    Full Text Available A low-complexity saliency detection algorithm for perceptual video coding is proposed; low-level encoding information is adopted as the characteristics of visual perception analysis. Firstly, this algorithm employs motion vector (MV to extract temporal saliency region through fast MV noise filtering and translational MV checking procedure. Secondly, spatial saliency region is detected based on optimal prediction mode distributions in I-frame and P-frame. Then, it combines the spatiotemporal saliency detection results to define the video region of interest (VROI. The simulation results validate that the proposed algorithm can avoid a large amount of computation work in the visual perception characteristics analysis processing compared with other existing algorithms; it also has better performance in saliency detection for videos and can realize fast saliency detection. It can be used as a part of the video standard codec at medium-to-low bit-rates or combined with other algorithms in fast video coding.

  2. The Application of Visual Saliency Models in Objective Image Quality Assessment: A Statistical Evaluation.

    Zhang, Wei; Borji, Ali; Wang, Zhou; Le Callet, Patrick; Liu, Hantao

    2016-06-01

    Advances in image quality assessment have shown the potential added value of including visual attention aspects in its objective assessment. Numerous models of visual saliency are implemented and integrated in different image quality metrics (IQMs), but the gain in reliability of the resulting IQMs varies to a large extent. The causes and the trends of this variation would be highly beneficial for further improvement of IQMs, but are not fully understood. In this paper, an exhaustive statistical evaluation is conducted to justify the added value of computational saliency in objective image quality assessment, using 20 state-of-the-art saliency models and 12 best-known IQMs. Quantitative results show that the difference in predicting human fixations between saliency models is sufficient to yield a significant difference in performance gain when adding these saliency models to IQMs. However, surprisingly, the extent to which an IQM can profit from adding a saliency model does not appear to have direct relevance to how well this saliency model can predict human fixations. Our statistical analysis provides useful guidance for applying saliency models in IQMs, in terms of the effect of saliency model dependence, IQM dependence, and image distortion dependence. The testbed and software are made publicly available to the research community. PMID:26277009

  3. Aberrations in asymmetrical electron lenses.

    Fitzgerald, J P S; Word, R C; Könenkamp, R

    2012-08-01

    Starting from well established knowledge in light-optics we explore the question if electron-optical aberration can be improved in asymmetrical electron lenses. We show that spherical as well as chromatic aberration coefficients are reduced in asymmetric electrostatic einzel lenses when the center electrode is moved away from the center position towards the entrance electrode. Relative improvements up to 40% for both the chromatic and the spherical aberration coefficients can be obtained. We use analytical and numerical calculations to confirm this result for exemplary cases of a lens with fixed length and working distance. The agreement of the two calculation methods is very good. We then derive an estimate for the electron-optical aberration coefficients from light-optics. The derived expressions for chromatic and spherical aberrations are somewhat simpler than the ones derived from electron-optics as they involve integrals only over the electrostatic potential, not over the electron paths. The estimated formulas still agree well with the electron optical calculations. Overall, we are tempted to suggest that the enormous knowledge base of light optics can provide considerable guidance for electron-optical applications. PMID:22206603

  4. Aberrations of diffracted wave fields.

    Harvey, J E; Shack, R V

    1978-09-15

    This paper is an attempt to provide new insight into the behavior of near-field scalar diffraction phenomena by showing that the Rayleigh-Sommerfeld diffraction integral is equivalent to the Fourier transform integral of a generalized pupil function which includes a term that represents phase errors in the aperture. This term can be interpreted as describing a conventional wavefront aberration function. The resulting aberration coefficients are calculated and expressed in terms of the aperture diameter, observation distance, and appropriate field parameter for several different geometrical configurations of incident beam and observation space. These aberrations, which are inherently associated with the diffraction process, are precisely the effects ignored when making the usual Fresnel and Fraunhofer approximations. PMID:20203910

  5. Dorsolateral Prefrontal Contributions to Human Intelligence

    Aron K Barbey; Colom, Roberto; Grafman, Jordan

    2012-01-01

    Although cognitive neuroscience has made remarkable progress in understanding the involvement of the prefrontal cortex in executive control functions for human intelligence, the necessity of the dorsolateral prefrontal cortex (dlPFC) for key competencies of general intelligence and executive function remains to be well established. Here we studied human brain lesion patients with dlPFC lesions to investigate whether this region is computationally necessary for performance on neuropsychologica...

  6. Chromosome Aberrations by Heavy Ions

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  7. Increased prefrontal and parahippocampal activation with reduced dorsolateral prefrontal and insular cortex activation to food images in obesity: a meta-analysis of fMRI studies.

    Samantha J Brooks

    Full Text Available BACKGROUND AND OBJECTIVES: Obesity is emerging as the most significant health concern of the twenty-first century. A wealth of neuroimaging data suggest that weight gain might be related to aberrant brain function, particularly in prefrontal cortical regions modulating mesolimbic addictive responses to food. Nevertheless, food addiction is currently a model hotly debated. Here, we conduct a meta-analysis of neuroimaging data, examining the most common functional differences between normal-weight and obese participants in response to food stimuli. DATA SOURCE: We conducted a search using several journal databases and adhered to the 'Preferred Reporting Items for Systematic Reviews and Meta-analyses' (PRISMA method. To this aim, 10 studies were found with a total of 126 obese participants, 129 healthy controls, equaling 184 foci (146 increased, 38 decreased activation using the Activation Likelihood Estimation (ALE technique. Out of the 10 studies, 7 investigated neural responses to food versus non-food images. RESULTS: In response to food images, obese in comparison to healthy weight subjects had increased activation in the left dorsomedial prefrontal cortex, right parahippocampal gyrus, right precentral gyrus and right anterior cingulate cortex, and reduced activation in the left dorsolateral prefrontal cortex and left insular cortex. CONCLUSIONS: Prefrontal cortex areas linked to cognitive evaluation processes, such as evaluation of rewarding stimuli, as well as explicit memory regions, appear most consistently activated in response to images of food in those who are obese. Conversely, a reduced activation in brain regions associated with cognitive control and interoceptive awareness of sensations in the body might indicate a weakened control system, combined with hypo-sensitivity to satiety and discomfort signals after eating in those who are prone to overeat.

  8. Sex ratio influences the motivational salience of facial attractiveness

    Hahn, A. C; Fisher, C. I.; DeBruine, L. M.; Jones, B. C.

    2014-01-01

    The sex ratio of the local population influences mating-related behaviours in many species. Recent experiments show that male-biased sex ratios increase the amount of financial resources men will invest in potential mates, suggesting that sex ratios influence allocation of mating effort in humans. To investigate this issue further, we tested for effects of cues to the sex ratio of the local population on the motivational salience of attractiveness in own-sex and opposite-sex faces. We did thi...

  9. Preserving visual saliency in image to sound substitution systems

    Ancuti, Codruta O.; Ancuti, Cosmin; Bekaert, Philippe

    2009-02-01

    Color plays a significant role in the scene interpretation in terms of visual perception. Numerous visual substitution systems deal with grayscale images disregarding this information from original image. Visually percept color-based details often fade due to the grayscale conversion and that can mislead the overall comprehension of the considered scene. We present a decolorization method that considers color contrast and preserve color saliency after transformation. We exploit this model to enhance the perception of visually disable persons over the interpreted images by the substitution system. The results demonstrate that our enhance system is capable to improves the overall scene interpretation in comparison with similar substitution system.

  10. Do stakeholder management strategy and salience influence corporate social responsibility in Indian companies?

    Supriti Mishra; Damodar Suar

    2010-01-01

    Purpose – This study aims to examine whether strategy towards primary stakeholders and their salience influence corporate social responsibility towards the corresponding stakeholders. Design/methodology/approach – Data were collected through a questionnaire from 150 senior level managers including CEOs. The stakeholder management strategy, salience, and corporate social responsibility were assessed in the context of employees, customers, investors, community, natural environment, and supplier...

  11. Transformational leadership and employees career salience; an empirical study conducted on banks of Pakistan

    Tabassum Riaz; Muhammad Ramzan; Hafiz Muhammad Ishaq; Muhammad Umair Akram

    2012-01-01

    The following study examines the relationship between transformational leadership and employees’ career salience. This research is conducted to answer the question that whether employees’ career salience has association with transformational leadership. This study focuses only on banking sector. Transformational leadership is measured using its four dimensions i.e. idealized influence, intellectual stimulation, inspirational motivation and individualized considerations, relationship is determ...

  12. How Important Are Items on a Student Evaluation? A Study of Item Salience

    Hills, Stacey Barlow; Naegle, Natali; Bartkus, Kenneth R.

    2009-01-01

    Although student evaluations of teaching (SETs) have been the subject of numerous research studies, the salience of SET items to students has not been examined. In the present study, the authors surveyed 484 students from a large public university. The authors suggest that not all items are viewed equally and that measures of item salience can…

  13. "Always in My Face": An Exploration of Social Class Consciousness, Salience, and Values

    Martin, Georgianna L.

    2015-01-01

    This qualitative study explores social class consciousness, salience, and values of White, low-income, first-generation college students. Overall, participants minimized the salience of social class as an aspect of their identity with many of them expressing that they did not want their social class to define them. Although participants largely…

  14. Target detection method based on supervised saliency map and efficient subwindow search

    Liu, Songtao; Jiang, Ning; Liu, Zhenxing

    2015-10-01

    In order to realize fast target detection under complex image scene, a novel method is proposed based on supervised saliency map and efficient subwindow search. Supervised saliency map generation mainly includes: (1) the original image is segmented by different parameters to obtain multi-segmentation results; (2) regional feature is mapped for salient value by random forest regressor; (3) obtain saliency map by fusing multi-level segmentation results. Efficient subwindow search method is implemented by transforming salient target detection as maximum saliency density, and using branch and bound algorithm to localize the maximum saliency density in global optimum. The experimental results show that the new method can not only detect salient region, but also recognize this region in some extent.

  15. Auditory Connections and Functions of Prefrontal Cortex

    BethanyPlakke

    2014-07-01

    Full Text Available The functional auditory system extends from the ears to the frontal lobes with successively more complex functions occurring as one ascends the hierarchy of the nervous system. Several areas of the frontal lobe receive afferents from both early and late auditory processing regions within the temporal lobe. Afferents from the early part of the cortical auditory system, the auditory belt cortex, which are presumed to carry information regarding auditory features of sounds, project to only a few prefrontal regions and are most dense in the ventrolateral prefrontal cortex (VLPFC. In contrast, projections from the parabelt and the rostral superior temporal gyrus (STG most likely convey more complex information and target a larger, widespread region of the prefrontal cortex. Neuronal responses reflect these anatomical projections as some prefrontal neurons exhibit responses to features in acoustic stimuli, while other neurons display task-related responses. For example, recording studies in non-human primates indicate that VLPFC is responsive to complex sounds including vocalizations and that VLPFC neurons in area 12/47 respond to sounds with similar acoustic morphology. In contrast, neuronal responses during auditory working memory involve a wider region of the prefrontal cortex. In humans, the frontal lobe is involved in auditory detection, discrimination, and working memory. Past research suggests that dorsal and ventral subregions of the prefrontal cortex process different types of information with dorsal cortex processing spatial/visual information and ventral cortex processing non-spatial/auditory information. While this is apparent in the non-human primate and in some neuroimaging studies, most research in humans indicates that specific task conditions, stimuli or previous experience may bias the recruitment of specific prefrontal regions, suggesting a more flexible role for the frontal lobe during auditory cognition.

  16. Inherent Difference in Saliency for Generators with Different PM Materials

    Sandra Eriksson

    2014-01-01

    Full Text Available The inherent differences between salient and nonsalient electrical machines are evaluated for two permanent magnet generators with different configurations. The neodymium based (NdFeB permanent magnets (PMs in a generator are substituted with ferrite magnets and the characteristics of the NdFeB generator and the ferrite generator are compared through FEM simulations. The NdFeB generator is a nonsalient generator, whereas the ferrite machine is a salient-pole generator, with small saliency. The two generators have almost identical properties at rated load operation. However, at overload the behaviour differs between the two generators. The salient-pole, ferrite generator has lower maximum torque than the NdFeB generator and a larger voltage drop at high current. It is concluded that, for applications where overload capability is important, saliency must be considered and the generator design adapted according to the behaviour at overload operation. Furthermore, if the maximum torque is the design criteria, additional PM mass will be required for the salient-pole machine.

  17. Emotional salience, emotional awareness, peculiar beliefs, and magical thinking.

    Berenbaum, Howard; Boden, M Tyler; Baker, John P

    2009-04-01

    Two studies with college student participants (Ns = 271 and 185) tested whether peculiar beliefs and magical thinking were associated with (a) the emotional salience of the stimuli about which individuals may have peculiar beliefs or magical thinking, (b) attention to emotion, and (c) clarity of emotion. Study 1 examined belief that a baseball team was cursed. Study 2 measured magical thinking using a procedure developed by P. Rozin and C. Nemeroff (2002). In both studies, peculiar beliefs and magical thinking were associated with Salience x Attention x Clarity interactions. Among individuals for whom the objects of the belief-magical thinking were highly emotionally salient and who had high levels of attention to emotion, higher levels of emotional clarity were associated with increased peculiar beliefs-magical thinking. In contrast, among individuals for whom the objects of the belief-magical thinking were not emotionally salient and who had high levels of attention to emotion, higher levels of emotional clarity were associated with diminished peculiar beliefs-magical thinking. PMID:19348532

  18. Perceptual Object Extraction Based on Saliency and Clustering

    Qiaorong Zhang

    2010-08-01

    Full Text Available Object-based visual attention has received an increasing interest in recent years. Perceptual object is the basic attention unit of object-based visual attention. The definition and extraction of perceptual objects is one of the key technologies in object-based visual attention computation model. A novel perceptual object definition and extraction method is proposed in this paper. Based on Gestalt theory and visual feature integration theory, perceptual object is defined using homogeneity region, salient region and edges. An improved saliency map generating algorithm is employed first. Based on the saliency map, salient edges are extracted. Then graph-based clustering algorithm is introduced to get homogeneity regions in the image. Finally an integration strategy is adopted to combine salient edges and homogeneity regions to extract perceptual objects. The proposed perceptual object extraction method has been tested on lots of natural images. Experiment results and analysis are presented in this paper also. Experiment results show that the proposed method is reasonable and valid.

  19. Scalable mobile image retrieval by exploring contextual saliency.

    Yang, Xiyu; Qian, Xueming; Xue, Yao

    2015-06-01

    Nowadays, it is very convenient to capture photos by a smart phone. As using, the smart phone is a convenient way to share what users experienced anytime and anywhere through social networks, it is very possible that we capture multiple photos to make sure the content is well photographed. In this paper, an effective scalable mobile image retrieval approach is proposed by exploring contextual salient information for the input query image. Our goal is to explore the high-level semantic information of an image by finding the contextual saliency from multiple relevant photos rather than solely using the input image. Thus, the proposed mobile image retrieval approach first determines the relevant photos according to visual similarity, then mines salient features by exploring contextual saliency from multiple relevant images, and finally determines contributions of salient features for scalable retrieval. Compared with the existing mobile-based image retrieval approaches, our approach requires less bandwidth and has better retrieval performance. We can carry out retrieval with retrieval. Experimental results show the effectiveness of the proposed approach. PMID:25775488

  20. Distortion of ultrashort pulses caused by aberrations

    Horváth, Z. L.; Kovács, A. P.; Bor, Zs.

    The effect of the primary wave aberrations (spherical aberration, astigmatism and coma) on ultrashort pulses is studied by the Nijboer-Zernike theory. The results of the geometrical and the wave optical treatments are compared.

  1. Baseline chromosome aberrations in children

    Merlo, D.F.; Ceppi, M.; Stagi, E.; Bocchini, V.; Šrám, Radim; Rössner st., Pavel

    2007-01-01

    Roč. 172, - (2007), s. 60-67. ISSN 0378-4274 Grant ostatní: EU(EU) 2002-02198; EU(EU) 2005-016320 Institutional research plan: CEZ:AV0Z50390512 Source of funding: R - rámcový projekt EK ; R - rámcový projekt EK Keywords : chromosome aberrations * children * molecular epidemiology Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.826, year: 2007

  2. Aberrant methylation patterns in cancer

    Hudler, Petra; Videtič, Alja

    2016-01-01

    Epigenetic mechanisms, such as DNA methylation, DNA hydroxymethylation, post-translational modifications (PTMs) of histone proteins affecting nucleosome remodelling, and regulation by small and large non-coding RNAs (ncRNAs) work in concert with cis and trans acting elements to drive appropriate gene expression. Advances in detection methods and development of dedicated platforms and methylation arrays resulted in an explo - sion of information on aberrantly methylated sequences linking devia...

  3. Correspondences among pupillary dilation response, subjective salience of sounds, and loudness.

    Liao, Hsin-I; Kidani, Shunsuke; Yoneya, Makoto; Kashino, Makio; Furukawa, Shigeto

    2016-04-01

    A pupillary dilation response is known to be evoked by salient deviant or contrast auditory stimuli, but so far a direct link between it and subjective salience has been lacking. In two experiments, participants listened to various environmental sounds while their pupillary responses were recorded. In separate sessions, participants performed subjective pairwise-comparison tasks on the sounds with respect to their salience, loudness, vigorousness, preference, beauty, annoyance, and hardness. The pairwise-comparison data were converted to ratings on the Thurstone scale. The results showed a close link between subjective judgments of salience and loudness. The pupil dilated in response to the sound presentations, regardless of sound type. Most importantly, this pupillary dilation response to an auditory stimulus positively correlated with the subjective salience, as well as the loudness, of the sounds (Exp. 1). When the loudnesses of the sounds were identical, the pupil responses to each sound were similar and were not correlated with the subjective judgments of salience or loudness (Exp. 2). This finding was further confirmed by analyses based on individual stimulus pairs and participants. In Experiment 3, when salience and loudness were manipulated by systematically changing the sound pressure level and acoustic characteristics, the pupillary dilation response reflected the changes in both manipulated factors. A regression analysis showed a nearly perfect linear correlation between the pupillary dilation response and loudness. The overall results suggest that the pupillary dilation response reflects the subjective salience of sounds, which is defined, or is heavily influenced, by loudness. PMID:26163191

  4. Salience and Attention in Surprisal-Based Accounts of Language Processing

    Zarcone, Alessandra; van Schijndel, Marten; Vogels, Jorrig; Demberg, Vera

    2016-01-01

    The notion of salience has been singled out as the explanatory factor for a diverse range of linguistic phenomena. In particular, perceptual salience (e.g., visual salience of objects in the world, acoustic prominence of linguistic sounds) and semantic-pragmatic salience (e.g., prominence of recently mentioned or topical referents) have been shown to influence language comprehension and production. A different line of research has sought to account for behavioral correlates of cognitive load during comprehension as well as for certain patterns in language usage using information-theoretic notions, such as surprisal. Surprisal and salience both affect language processing at different levels, but the relationship between the two has not been adequately elucidated, and the question of whether salience can be reduced to surprisal / predictability is still open. Our review identifies two main challenges in addressing this question: terminological inconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalize upon work in visual cognition in order to orient ourselves in surveying the different facets of the notion of salience in linguistics and their relation with models of surprisal. We find that work on salience highlights aspects of linguistic communication that models of surprisal tend to overlook, namely the role of attention and relevance to current goals, and we argue that the Predictive Coding framework provides a unified view which can account for the role played by attention and predictability at different levels of processing and which can clarify the interplay between low and high levels of processes and between predictability-driven expectation and attention-driven focus. PMID:27375525

  5. Salience and attention in surprisal-based accounts of language processing

    Alessandra eZarcone

    2016-06-01

    Full Text Available The notion of salience has been singled out as the explanatory factor for a diverse range oflinguistic phenomena. In particular, perceptual salience (e.g. visual salience of objects in the world,acoustic prominence of linguistic sounds and semantic-pragmatic salience (e.g. prominence ofrecently mentioned or topical referents have been shown to influence language comprehensionand production. A different line of research has sought to account for behavioral correlates ofcognitive load during comprehension as well as for certain patterns in language usage usinginformation-theoretic notions, such as surprisal. Surprisal and salience both affect languageprocessing at different levels, but the relationship between the two has not been adequatelyelucidated, and the question of whether salience can be reduced to surprisal / predictability isstill open. Our review identifies two main challenges in addressing this question: terminologicalinconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalise upon work in visual cognition inorder to orient ourselves in surveying the different facets of the notion of salience in linguisticsand their relation with models of surprisal. We find that work on salience highlights aspects oflinguistic communication that models of surprisal tend to overlook, namely the role of attentionand relevance to current goals, and we argue that the Predictive Coding framework provides aunified view which can account for the role played by attention and predictability at different levelsof processing and which can clarify the interplay between low and high levels of processes andbetween predictability-driven expectation and attention-driven focus.

  6. Salience and Attention in Surprisal-Based Accounts of Language Processing.

    Zarcone, Alessandra; van Schijndel, Marten; Vogels, Jorrig; Demberg, Vera

    2016-01-01

    The notion of salience has been singled out as the explanatory factor for a diverse range of linguistic phenomena. In particular, perceptual salience (e.g., visual salience of objects in the world, acoustic prominence of linguistic sounds) and semantic-pragmatic salience (e.g., prominence of recently mentioned or topical referents) have been shown to influence language comprehension and production. A different line of research has sought to account for behavioral correlates of cognitive load during comprehension as well as for certain patterns in language usage using information-theoretic notions, such as surprisal. Surprisal and salience both affect language processing at different levels, but the relationship between the two has not been adequately elucidated, and the question of whether salience can be reduced to surprisal / predictability is still open. Our review identifies two main challenges in addressing this question: terminological inconsistency and lack of integration between high and low levels of representations in salience-based accounts and surprisal-based accounts. We capitalize upon work in visual cognition in order to orient ourselves in surveying the different facets of the notion of salience in linguistics and their relation with models of surprisal. We find that work on salience highlights aspects of linguistic communication that models of surprisal tend to overlook, namely the role of attention and relevance to current goals, and we argue that the Predictive Coding framework provides a unified view which can account for the role played by attention and predictability at different levels of processing and which can clarify the interplay between low and high levels of processes and between predictability-driven expectation and attention-driven focus. PMID:27375525

  7. Learning to predict where human gaze is using quaternion DCT based regional saliency detection

    Li, Ting; Xu, Yi; Zhang, Chongyang

    2014-09-01

    Many current visual attention approaches used semantic features to accurately capture human gaze. However, these approaches demand high computational cost and can hardly be applied to daily use. Recently, some quaternion-based saliency detection models, such as PQFT (phase spectrum of Quaternion Fourier Transform), QDCT (Quaternion Discrete Cosine Transform), have been proposed to meet real-time requirement of human gaze tracking tasks. However, current saliency detection methods used global PQFT and QDCT to locate jump edges of the input, which can hardly detect the object boundaries accurately. To address the problem, we improved QDCT-based saliency detection model by introducing superpixel-wised regional saliency detection mechanism. The local smoothness of saliency value distribution is emphasized to distinguish noises of background from salient regions. Our algorithm called saliency confidence can distinguish the patches belonging to the salient object and those of the background. It decides whether the image patches belong to the same region. When an image patch belongs to a region consisting of other salient patches, this patch should be salient as well. Therefore, we use saliency confidence map to get background weight and foreground weight to do the optimization on saliency map obtained by QDCT. The optimization is accomplished by least square method. The optimization approach we proposed unifies local and global saliency by combination of QDCT and measuring the similarity between each image superpixel. We evaluate our model on four commonly-used datasets (Toronto, MIT, OSIE and ASD) using standard precision-recall curves (PR curves), the mean absolute error (MAE) and area under curve (AUC) measures. In comparison with most state-of-art models, our approach can achieve higher consistency with human perception without training. It can get accurate human gaze even in cluttered background. Furthermore, it achieves better compromise between speed and accuracy.

  8. Effects of early adolescent environmental enrichment on cognitive dysfunction, prefrontal cortex development, and inflammatory cytokines after early life stress.

    do Prado, Carine H; Narahari, Tanya; Holland, Freedom H; Lee, Ha-Neul; Murthy, Shashi K; Brenhouse, Heather C

    2016-05-01

    Early postnatal stress such as maternal separation causes cognitive dysfunction later in life, including working memory deficits that are largely mediated by the prefrontal cortex. Maternal separation in male rats also yields a loss of parvalbumin-containing prefrontal cortex interneurons in adolescence, which may occur via inflammatory or oxidative stress mechanisms. Environmental enrichment can prevent several effects of maternal separation; however, effects of enrichment on prefrontal cortex development are not well understood. Here, we report that enrichment prevented cognitive dysfunction in maternally separated males and females, and prevented elevated circulating pro-inflammatory cytokines that was evident in maternally separated males, but not females. However, enrichment did not prevent parvalbumin loss or adolescent measures of oxidative stress. Significant correlations indicated that adolescents with higher oxidative damage and less prefrontal cortex parvalbumin in adolescence committed more errors on the win-shift task; therefore, maternal separation may affect cognitive dysfunction via aberrant interneuron development. © 2015 Wiley Periodicals, Inc. Dev Psychobiol 58: 482-491, 2016. PMID:26688108

  9. Clozapine Functions Through the Prefrontal Cortex Serotonin 1A Receptor to Heighten Neuronal Activity via Calmodulin Kinase II-NMDA Receptor Interactions

    Purkayastha, Sudarshana; Ford, Jason; Kanjilal, Baishali; Diallo, Souleymane; Del Rosario Inigo, Joseph; Neuwirth, Lorenz; El Idrissi, Abdelsem; Ahmed, Zaghloul; Wieraszko, Andrzej; Efrain, C.; Azmitia; Banerjee, Probal

    2011-01-01

    Aberrant dopamine release in the prefrontal cortex (PFC) is believed to underlie schizophrenia, but the mechanistic pathway through which a widely used antipsychotic, clozapine (Clz), evokes neurotransmitter-releasing electrical stimulation is unclear. We analyzed Clz-evoked regulation of neuronal activity in the PFC by stimulating axons in layers IV and V and recording the electrical effect in the postsynaptic pyramidal cells of layers II and III. We observed a Clz-evoked increase in populat...

  10. Hopelessly Mortal: The Role of Mortality Salience, Immortality and Trait Self-esteem in Personal Hope

    Wisman, Arnaud; Heflick, Nathan A

    2015-01-01

    Do people lose hope when thinking about death? Based on Terror Management Theory, we predicted that thoughts of death (i.e., mortality salience) would reduce personal hope for people low, but not high, in self-esteem, and that this reduction in hope would be ameliorated by promises of immortality. In Studies 1 and 2, mortality salience reduced personal hope for people low in self-esteem, but not for people high in self-esteem. In Study 3, mortality salience reduced hope for people low in self...

  11. Incentive salience attribution under reward uncertainty: A Pavlovian model.

    Anselme, Patrick

    2015-02-01

    There is a vast literature on the behavioural effects of partial reinforcement in Pavlovian conditioning. Compared with animals receiving continuous reinforcement, partially rewarded animals typically show (a) a slower development of the conditioned response (CR) early in training and (b) a higher asymptotic level of the CR later in training. This phenomenon is known as the partial reinforcement acquisition effect (PRAE). Learning models of Pavlovian conditioning fail to account for it. In accordance with the incentive salience hypothesis, it is here argued that incentive motivation (or 'wanting') plays a more direct role in controlling behaviour than does learning, and reward uncertainty is shown to have an excitatory effect on incentive motivation. The psychological origin of that effect is discussed and a computational model integrating this new interpretation is developed. Many features of CRs under partial reinforcement emerge from this model. PMID:25444780

  12. Mortality salience increases defensive distancing from people with terminal cancer.

    Smith, Lauren M; Kasser, Tim

    2014-01-01

    Based on principles of terror management theory, the authors hypothesized that participants would distance more from a target person with terminal cancer than from a target with arthritis, and that this effect would be stronger following mortality salience. In Study 1, adults rated how similar their personalities were to a target person; in Study 2, participants arranged two chairs in preparation for meeting the target person. Both studies found that distancing from the person with terminal cancer increased after participants wrote about their own death (vs. giving a speech). Thus, death anxiety may explain why people avoid close contact with terminally ill people; further analyses suggest that gender and self-esteem may also influence such distancing from the terminally ill. PMID:24521045

  13. Decisive Visual Saliency and Consumers' In-store Decisions

    Clement, Jesper; Aastrup, Jesper; Forsberg, Signe Charlotte

    2015-01-01

    that they are affected by the visual stimuli in the store. The objective for this paper is to investigate the visual saliency from two factors: 1) in-store signage and 2) placement of products. This is done by a triangulation method where we utilize data from an eye-track study and sales data from...... grocery stores. The first study takes place in laboratory settings with a simulated purchase situation, and the second research design builds on manipulated in-store settings and data from real purchases. We found optimal placement of two comparable goods (branded good and private label) to increase...... visual attention and sale for both goods. The use of signage increases visual attention and sale as well, yet only for the product that the label addressed, implying a cannibalization effect. The limitation of the study and implications for retail managers and for brand owners are discussed....

  14. The time course of color- and luminance-based salience effects.

    Isabel C Dombrowe

    2010-11-01

    Full Text Available Salient objects in the visual field attract our attention. Recent work in the orientation domain has shown that the effects of the relative salience of two singleton elements on covert visual attention disappear over time. The present study aims to investigate how salience derived from color and luminance differences affects covert selection. In two experiments, observers indicated the location of a probe which was presented at different stimulus-onset-asynchronies after the presentation of a singleton display containing a homogeneous array of oriented lines and two distinct color singletons (Experiment 1 or luminance singletons (Experiment 2. The results show that relative singleton salience from luminance and color differences, just as from orientation differences, affects covert visual attention in a brief time span after stimulus onset. The mere presence of an object, however, can affect covert attention for a longer time span regardless of salience.

  15. Development of salience-driven and visually-guided eye movement responses.

    Kooiker, Marlou J G; van der Steen, Johannes; Pel, Johan J M

    2016-03-01

    Development of visuospatial attention can be quantified from infancy onward using visually-guided eye movement responses. We investigated the interaction between eye movement response times and salience in target areas of visual stimuli over age in a cohort of typically developing children. A preferential looking (PL) paradigm consisting of stimuli with six different visual modalities (cartoons, contrast, form, local motion, color, global motion) was combined with the automated measurement of reflexive eye movements. Effective salience was defined as visual salience of each target area relative to its background. Three classes of PL stimuli were used: with high- (cartoon, contrast), intermediate- (local motion, form), and low-effective salience (global motion, color). Eye movement response times to the target areas of the six PL stimuli were nonverbally assessed in 220 children aged 1-12 years. The development of response times with age was influenced by effective salience: Response times to targets with high salience reached stable values earlier in development (around 4 years of age) than to targets with low salience (around 9 years of age). Intra-individual response time variability was highest for low-salient stimuli, and stabilized later (around 4 years) than for highly salient stimuli (2 years). The improvement of eye movement response times to visual modalities in PL stimuli occurred earlier in development for highly salient than for low-salient targets. The present age-dependent and salience-related results provide a quantitative and theoretical framework to assess the development of visuospatial attention, and of related visual processing capacities, in children from 1 year of age. PMID:26998802

  16. Hypergraph-based saliency map generation with potential region-of-interest approximation and validation

    Liang, Zhen; Fu, Hong; Chi, Zheru; Feng, Dagan

    2012-01-01

    A novel saliency model is proposed in this paper to automatically process images in the similar way as the human visual system which focuses on conspicuous regions that catch human beings' attention. The model combines a hypergraph representation and a partitioning process with potential region-of-interest (p-ROI) approximation and validation. Experimental results demonstrate that the proposed method shows considerable improvement in the performance of saliency map generation.

  17. Evidence Inhibition Responds Reactively to the Salience of Distracting Information during Focused Attention

    Natalie Wyatt; Liana Machado

    2013-01-01

    Along with target amplification, distractor inhibition is regarded as a major contributor to selective attention. Some theories suggest that the strength of inhibitory processing is proportional to the salience of the distractor (i.e., inhibition reacts to the distractor intensity). Other theories suggest that the strength of inhibitory processing does not depend on the salience of the distractor (i.e., inhibition does not react to the distractor intensity). The present study aimed to elucida...

  18. Fusion of multi-sensory saliency maps for automated perception and control

    Huber, David J.; Khosla, Deepak; Dow, Paul A.

    2009-05-01

    In many real-world situations and applications that involve humans or machines (e.g., situation awareness, scene understanding, driver distraction, workload reduction, assembly, robotics, etc.) multiple sensory modalities (e.g., vision, auditory, touch, etc.) are used. The incoming sensory information can overwhelm processing capabilities of both humans and machines. An approach for estimating what is most important in our sensory environment (bottom-up or goal-driven) and using that as a basis for workload reduction or taking an action could be of great benefit in applications involving humans, machines or human-machine interactions. In this paper, we describe a novel approach for determining high saliency stimuli in multi-modal sensory environments, e.g., vision, sound, touch, etc. In such environments, the high saliency stimuli could be a visual object, a sound source, a touch event, etc. The high saliency stimuli are important and should be attended to from perception, cognition or/and action perspective. The system accomplishes this by the fusion of saliency maps from multiple sensory modalities (e.g., visual and auditory) into a single, fused multimodal saliency map that is represented in a common, higher-level coordinate system. This paper describes the computational model and method for generating multi-modal or fused saliency map. The fused saliency map can be used to determine primary and secondary foci of attention as well as for active control of a hardware/device. Such a computational model of fused saliency map would be immensely useful for a machine-based or robot-based application in a multi-sensory environment. We describe the approach, system and present preliminary results on a real-robotic platform.

  19. The Time Course of Color- and Luminance-Based Salience Effects

    MiekeDonk

    2010-01-01

    Salient objects in the visual field attract our attention. Recent work in the orientation domain has shown that the effects of the relative salience of two singleton elements on covert visual attention disappear over time. The present study aims to investigate how salience derived from color and luminance differences affects covert selection. In two experiments, observers indicated the location of a probe which was presented at different stimulus-onset-asynchronies after the presentation of a...

  20. OBJECTIVE PREDICTION OF VISUAL SALIENCY MAPS IN EGOCENTRIC VIDEOS FOR CONTENT-ACTION INTERPRETATION

    Boujut, Hugo; Buso, Vincent; Benois-Pineau, Jenny

    2013-01-01

    Extraction of visual saliency from video is in the focus of in- tensive research nowadays due to the variety and importance of application areas. In this paper we study the relation be- tween subjective saliency maps, recorded on the basis of gaze- tracker data in a new upcoming video content: the egocentric video recorded with wearable cameras. On the basis of phys- iological research and comparing the subjective maps of an Actor performing activities of everyday life and a Viewer who interp...

  1. Competition of synonyms through time : Conceptual and social salience factors and their interrelations

    Soares da Silva, Augusto

    2015-01-01

    This paper highlights three theoretical and descriptive insights into synonymy and lexical variation and change: (1) the diachronic development of synonymous forms reveals essential aspects about the nature and motivations of synonymy; (2) the emergence and competition of synonymous forms can either result from conceptual salience factors or from social salience factors; (3) synonym competition sheds light upon processes of language variation and change. Focusing on the interplay between conc...

  2. DeepSaliency: Multi-Task Deep Neural Network Model for Salient Object Detection.

    Li, Xi; Zhao, Liming; Wei, Lina; Yang, Ming-Hsuan; Wu, Fei; Zhuang, Yueting; Ling, Haibin; Wang, Jingdong

    2016-08-01

    A key problem in salient object detection is how to effectively model the semantic properties of salient objects in a data-driven manner. In this paper, we propose a multi-task deep saliency model based on a fully convolutional neural network with global input (whole raw images) and global output (whole saliency maps). In principle, the proposed saliency model takes a data-driven strategy for encoding the underlying saliency prior information, and then sets up a multi-task learning scheme for exploring the intrinsic correlations between saliency detection and semantic image segmentation. Through collaborative feature learning from such two correlated tasks, the shared fully convolutional layers produce effective features for object perception. Moreover, it is capable of capturing the semantic information on salient objects across different levels using the fully convolutional layers, which investigate the feature-sharing properties of salient object detection with a great reduction of feature redundancy. Finally, we present a graph Laplacian regularized nonlinear regression model for saliency refinement. Experimental results demonstrate the effectiveness of our approach in comparison with the state-of-the-art approaches. PMID:27305676

  3. The Motivational Salience of Faces Is Related to Both Their Valence and Dominance.

    Wang, Hongyi; Hahn, Amanda C; DeBruine, Lisa M; Jones, Benedict C

    2016-01-01

    Both behavioral and neural measures of the motivational salience of faces are positively correlated with their physical attractiveness. Whether physical characteristics other than attractiveness contribute to the motivational salience of faces is not known, however. Research with male macaques recently showed that more dominant macaques' faces hold greater motivational salience. Here we investigated whether dominance also contributes to the motivational salience of faces in human participants. Principal component analysis of third-party ratings of faces for multiple traits revealed two orthogonal components. The first component ("valence") was highly correlated with rated trustworthiness and attractiveness. The second component ("dominance") was highly correlated with rated dominance and aggressiveness. Importantly, both components were positively and independently related to the motivational salience of faces, as assessed from responses on a standard key-press task. These results show that at least two dissociable components underpin the motivational salience of faces in humans and present new evidence for similarities in how humans and non-human primates respond to facial cues of dominance. PMID:27513859

  4. Chromosomal aberrations and bone marrow toxicity.

    Heddle, J A; Salamone, M F

    1981-01-01

    The importance of chromosomal aberrations as a proximate cause of bone marrow toxicity is discussed. Since chemicals that can cause nondisjunction are rare, numerical aberrations (aneuploidy, polyploidy) are not ordinarily important. Many structural aberrations, however, can lead directly to cell death and so are proximate causes of toxicity when they occur. The micronucleus test which utilizes the polychromatic erythrocyte is capable of detecting agents (clastogens) that can cause such struc...

  5. Chromosomal aberrations in ore miners of Slovakia

    A pilot study was performed in which the incidence of chromosomal aberrations in lymphocytes of miners in ore mines located in Central Slovakia was monitored and related to lifetime underground radon exposure and to lifetime smoking. The conclusions drawn from the results of the study were as follows: the counts of chromosomal aberrations in lymphocytes of miners were significantly higher than in an age matched control group of white-collar staff; the higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; a dependence of chromosomal aberration counts on the exposure to radon could not be assessed. (A.K.)

  6. Resting-State Coupling between Core Regions within the Central-Executive and Salience Networks Contributes to Working Memory Performance.

    Fang, Xiaojing; Zhang, Yuanchao; Zhou, Yuan; Cheng, Luqi; Li, Jin; Wang, Yulin; Friston, Karl J; Jiang, Tianzi

    2016-01-01

    Previous studies investigated the distinct roles played by different cognitive regions and suggested that the patterns of connectivity of these regions are associated with working memory (WM). However, the specific causal mechanism through which the neuronal circuits that involve these brain regions contribute to WM is still unclear. Here, in a large sample of healthy young adults, we first identified the core WM regions by linking WM accuracy to resting-state functional connectivity with the bilateral dorsolateral prefrontal cortex (dLPFC; a principal region in the central-executive network, CEN). Then a spectral dynamic causal modeling (spDCM) analysis was performed to quantify the effective connectivity between these regions. Finally, the effective connectivity was correlated with WM accuracy to characterize the relationship between these connections and WM performance. We found that the functional connections between the bilateral dLPFC and the dorsal anterior cingulate cortex (dACC) and between the right dLPFC and the left orbital fronto-insular cortex (FIC) were correlated with WM accuracy. Furthermore, the effective connectivity from the dACC to the bilateral dLPFC and from the right dLPFC to the left FIC could predict individual differences in WM. Because the dACC and FIC are core regions of the salience network (SN), we inferred that the inter- and causal-connectivity between core regions within the CEN and SN is functionally relevant for WM performance. In summary, the current study identified the dLPFC-related resting-state effective connectivity underlying WM and suggests that individual differences in cognitive ability could be characterized by resting-state effective connectivity. PMID:26941629

  7. Acute alcohol effects on attentional bias are mediated by subcortical areas associated with arousal and salience attribution.

    Nikolaou, Kyriaki; Field, Matt; Critchley, Hugo; Duka, Theodora

    2013-06-01

    Acute alcohol ingestion increases attentional bias to alcohol-related stimuli; however, the underlying cognitive and brain mechanisms remain unknown. We combined functional magnetic resonance imaging (fMRI) with performance of a dual task that probed attentional distraction by alcohol-related stimuli during 'conflict' processing: the Concurrent Flanker/Alcohol-Attentional bias task (CFAAT). In this task, an Eriksen Flanker task is superimposed on task-unrelated background pictures with alcohol-associated or neutral content. Participants respond to the direction of a central 'target' arrow and ignore adjacent congruent (low cognitive load) or incongruent (high cognitive load) 'flanking' arrows. Using a between-subject design, 40 healthy moderate-to-heavy social drinkers received either no alcohol (placebo), 0.4 g/kg (low dose), or 0.8 g/kg (high dose) of alcohol, and underwent fMRI while performing the CFAAT. The low alcohol dose, relative to placebo, increased response latencies on trials with alcohol-associated backgrounds and, under low cognitive load, increased the activity evoked by these pictures within a medial hypothalamic region. Under high cognitive load, the low alcohol dose, relative to placebo, elicited greater activity within a more lateral hypothalamic region, and reduced activity within frontal motor areas. The high alcohol dose, relative to placebo, did not reliably affect response latencies or neural responses to background images, but reduced overall accuracy under high cognitive load. This effect correlated with changes in reactivity within medial and dorsal prefrontal cortices. These data suggest that alcohol at a low dose primes attentional bias to alcohol-associated stimuli, an effect mediated by activation of subcortical hypothalamic areas implicated in arousal and salience attribution. PMID:23361162

  8. Specialized prefrontal “auditory fields”: organization of primate prefrontal-temporal pathways

    MariaMedalla

    2014-04-01

    Full Text Available No other modality is more frequently represented in the prefrontal cortex than the auditory, but the role of auditory information in prefrontal functions is not well understood. Pathways from auditory association cortices reach distinct sites in the lateral, orbital, and medial surfaces of the prefrontal cortex in rhesus monkeys. Among prefrontal areas, frontopolar area 10 has the densest interconnections with auditory association areas, spanning a large antero-posterior extent of the superior temporal gyrus from the temporal pole to auditory parabelt and belt regions. Moreover, auditory pathways make up the largest component of the extrinsic connections of area 10, suggesting a special relationship with the auditory modality. Here we review anatomic evidence showing that frontopolar area 10 is indeed the main frontal “auditory field” as the major recipient of auditory input in the frontal lobe and chief source of output to auditory cortices. Area 10 is thought to be the functional node for the most complex cognitive tasks of multitasking and keeping track of information for future decisions. These patterns suggest that the auditory association links of area 10 are critical for complex cognition. The first part of this review focuses on the organization of prefrontal-auditory pathways at the level of the system and the synapse, with a particular emphasis on area 10. Then we explore ideas on how the elusive role of area 10 in complex cognition may be related to the specialized relationship with auditory association cortices.

  9. Language-experience plasticity in neural representation of changes in pitch salience.

    Krishnan, Ananthanarayan; Gandour, Jackson T; Suresh, Chandan H

    2016-04-15

    Neural representation of pitch-relevant information at the brainstem and cortical levels of processing is influenced by language experience. A well-known attribute of pitch is its salience. Brainstem frequency following responses and cortical pitch specific responses, recorded concurrently, were elicited by a pitch salience continuum spanning weak to strong pitch of a dynamic, iterated rippled noise pitch contour-homolog of a Mandarin tone. Our aims were to assess how language experience (Chinese, English) affects i) enhancement of neural activity associated with pitch salience at brainstem and cortical levels, ii) the presence of asymmetry in cortical pitch representation, and iii) patterns of relative changes in magnitude along the pitch salience continuum. Peak latency (Fz: Na, Pb, and Nb) was shorter in the Chinese than the English group across the continuum. Peak-to-peak amplitude (Fz: Na-Pb, Pb-Nb) of the Chinese group grew larger with increasing pitch salience, but an experience-dependent advantage was limited to the Na-Pb component. At temporal sites (T7/T8), the larger amplitude of the Chinese group across the continuum was both limited to the Na-Pb component and the right temporal site. At the brainstem level, F0 magnitude gets larger as you increase pitch salience, and it too reveals Chinese superiority. A direct comparison of cortical and brainstem responses for the Chinese group reveals different patterns of relative changes in magnitude along the pitch salience continuum. Such differences may point to a transformation in pitch processing at the cortical level presumably mediated by local sensory and/or extrasensory influence overlaid on the brainstem output. PMID:26903418

  10. Preference for Well-Balanced Saliency in Details Cropped from Photographs

    Jonas eAbeln

    2016-01-01

    Full Text Available Photographic cropping is the act of selecting part of a photograph to enhance its aesthetic appearance or visual impact. It is common practice with both professional (expert and amateur (non-expert photographers. In a psychometric study, McManus et al. (2011b showed that participants cropped photographs confidently and reliably. Experts tended to select details from a wider range of positions than non-experts, but other croppers did not generally prefer details that were selected by experts. It remained unclear, however, on what grounds participants selected particular details from a photograph while avoiding other details. One of the factors contributing to cropping decision may be visual saliency. Indeed, various saliency-based computer algorithms are available for the automatic cropping of photographs. However, careful experimental studies on the relation between saliency and cropping are lacking to date. In the present study, we re-analyzed the data from the studies by McManus et al. (2011a,b, focusing on statistical image properties. We calculated saliency-based measures for details selected and details avoided during cropping. As expected, we found that selected details contain regions of higher saliency than avoided details on average. Moreover, the saliency center-of-mass was closer to the geometrical center in selected details than in avoided details. Results were confirmed in an eye tracking study with the same dataset of images. Interestingly, the observed regularities in cropping behavior were less pronounced for experts than for non-experts. In summary, our results suggest that, during cropping, participants tend to select salient regions and place them in an image composition that is well-balanced with respect to the distribution of saliency. Our study contributes to the knowledge of perceptual bottom-up features that are germane to aesthetic decisions in photography and their variability in non-experts and experts.

  11. A Novel GBM Saliency Detection Model Using Multi-Channel MRI.

    Subhashis Banerjee

    Full Text Available The automatic computerized detection of regions of interest (ROI is an important step in the process of medical image processing and analysis. The reasons are many, and include an increasing amount of available medical imaging data, existence of inter-observer and inter-scanner variability, and to improve the accuracy in automatic detection in order to assist doctors in diagnosing faster and on time. A novel algorithm, based on visual saliency, is developed here for the identification of tumor regions from MR images of the brain. The GBM saliency detection model is designed by taking cue from the concept of visual saliency in natural scenes. A visually salient region is typically rare in an image, and contains highly discriminating information, with attention getting immediately focused upon it. Although color is typically considered as the most important feature in a bottom-up saliency detection model, we circumvent this issue in the inherently gray scale MR framework. We develop a novel pseudo-coloring scheme, based on the three MRI sequences, viz. FLAIR, T2 and T1C (contrast enhanced with Gadolinium. A bottom-up strategy, based on a new pseudo-color distance and spatial distance between image patches, is defined for highlighting the salient regions in the image. This multi-channel representation of the image and saliency detection model help in automatically and quickly isolating the tumor region, for subsequent delineation, as is necessary in medical diagnosis. The effectiveness of the proposed model is evaluated on MRI of 80 subjects from the BRATS database in terms of the saliency map values. Using ground truth of the tumor regions for both high- and low- grade gliomas, the results are compared with four highly referred saliency detection models from literature. In all cases the AUC scores from the ROC analysis are found to be more than 0.999 ± 0.001 over different tumor grades, sizes and positions.

  12. Emergence of visual saliency from natural scenes via context-mediated probability distributions coding.

    Jinhua Xu

    Full Text Available Visual saliency is the perceptual quality that makes some items in visual scenes stand out from their immediate contexts. Visual saliency plays important roles in natural vision in that saliency can direct eye movements, deploy attention, and facilitate tasks like object detection and scene understanding. A central unsolved issue is: What features should be encoded in the early visual cortex for detecting salient features in natural scenes? To explore this important issue, we propose a hypothesis that visual saliency is based on efficient encoding of the probability distributions (PDs of visual variables in specific contexts in natural scenes, referred to as context-mediated PDs in natural scenes. In this concept, computational units in the model of the early visual system do not act as feature detectors but rather as estimators of the context-mediated PDs of a full range of visual variables in natural scenes, which directly give rise to a measure of visual saliency of any input stimulus. To test this hypothesis, we developed a model of the context-mediated PDs in natural scenes using a modified algorithm for independent component analysis (ICA and derived a measure of visual saliency based on these PDs estimated from a set of natural scenes. We demonstrated that visual saliency based on the context-mediated PDs in natural scenes effectively predicts human gaze in free-viewing of both static and dynamic natural scenes. This study suggests that the computation based on the context-mediated PDs of visual variables in natural scenes may underlie the neural mechanism in the early visual cortex for detecting salient features in natural scenes.

  13. Neural activities in V1 create the bottom-up saliency map of natural scenes.

    Chen, Cheng; Zhang, Xilin; Wang, Yizhou; Zhou, Tiangang; Fang, Fang

    2016-06-01

    A saliency map is the bottom-up contribution to the deployment of exogenous attention. It, as well as its underlying neural mechanism, is hard to identify because of the influence of top-down signals. A recent study showed that neural activities in V1 could create a bottom-up saliency map (Zhang et al. in Neuron 73(1):183-192, 2012). In this paper, we tested whether their conclusion can generalize to complex natural scenes. In order to avoid top-down influences, each image was presented with a low contrast for only 50 ms and was followed by a high contrast mask, which rendered the whole image invisible to participants (confirmed by a forced-choice test). The Posner cueing paradigm was adopted to measure the spatial cueing effect (i.e., saliency) by an orientation discrimination task. A positive cueing effect was found, and the magnitude of the cueing effect was consistent with the saliency prediction of a computational saliency model. In a following fMRI experiment, we used the same masked natural scenes as stimuli and measured BOLD signals responding to the predicted salient region (relative to the background). We found that the BOLD signal in V1, but not in other cortical areas, could well predict the cueing effect. These results suggest that the bottom-up saliency map of natural scenes could be created in V1, providing further evidence for the V1 saliency theory (Li in Trends Cogn Sci 6(1):9-16, 2002). PMID:26879771

  14. Calculation of aberration coefficients by ray tracing

    Oral, Martin; Lencová, Bohumila

    2009-01-01

    Roč. 109, č. 11 (2009), s. 1365-1373. ISSN 0304-3991 R&D Projects: GA AV ČR IAA100650805 Institutional research plan: CEZ:AV0Z20650511 Keywords : Aberrations * Aberration coefficients * Ray tracing * Regression * Fitting Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 2.067, year: 2009

  15. Nodal aberration theory applied to freeform surfaces

    Fuerschbach, Kyle; Rolland, Jannick P.; Thompson, Kevin P.

    2014-12-01

    When new three-dimensional packages are developed for imaging optical systems, the rotational symmetry of the optical system is often broken, changing its imaging behavior and making the optical performance worse. A method to restore the performance is to use freeform optical surfaces that compensate directly the aberrations introduced from tilting and decentering the optical surfaces. In order to effectively optimize the shape of a freeform surface to restore optical functionality, it is helpful to understand the aberration effect the surface may induce. Using nodal aberration theory the aberration fields induced by a freeform surface in an optical system are explored. These theoretical predications are experimentally validated with the design and implementation of an aberration generating telescope.

  16. Aberration compensation in charged particle projection lithography

    Projection systems offer the opportunity to increase the throughput for charged particle lithography, because such systems image a large area of a mask directly on to a wafer as a single shot. Shots have to be imaged over a certain range of off-axis distances at the wafer to increase the writing speed, because shot sizes are limited to about 0.25x0.25 mm2 due to aberrations. In a projection system with only lenses, however, the aberrations for off-axis shots are still very large, and some aberration compensation elements need to be introduced. In this paper, three aberration compensation elements (deflectors, stigmators and dynamic focus lenses) are first discussed, a suite of newly developed software, called PROJECTION, based on this principle and our unified aberration theory is then described, and an illustrative example computed with the software is finally given

  17. Higher-Order Aberrations in Myopic Eyes

    Farid Karimian

    2010-01-01

    Full Text Available Purpose: To evaluate the correlation between refractive error and higher-order aberrations (HOAs in patients with myopic astigmatism. Methods: HOAs were measured using the Zywave II aberrometer over a 6 mm pupil. Correlations between HOAs and myopia, astigmatism, and age were analyzed. Results: One hundred and twenty-six eyes of 63 subjects with mean age of 26.4±5.9 years were studied. Mean spherical equivalent refractive error and refractive astigmatism were -4.94±1.63 D and 0.96±1.06 D, respectively. The most common higher-order aberration was primary horizontal trefoil with mean value of 0.069±0.152 μm followed by spherical aberration (-0.064±0.130 μm and primary vertical coma (-0.038±0.148 μm. As the order of aberration increased from third to fifth, its contribution to total HOA decreased: 53.9% for third order, 31.9% for fourth order, and 14.2% for fifth order aberrations. Significant correlations were observed between spherical equivalent refractive error and primary horizontal coma (R=0.231, P=0.022, and root mean square (RMS of spherical aberration (R=0.213, P=0.031; between astigmatism and RMS of total HOA (R=0.251, P=0.032, RMS of fourth order aberration (R=0.35, P<0.001, and primary horizontal coma (R=0.314, P=0.004. Spherical aberration (R=0.214, P=0.034 and secondary vertical coma (R=0.203, P=0.031 significantly increased with age. Conclusion: Primary horizontal trefoil, spherical aberration and primary vertical coma are the predominant higher-order aberrations in eyes with myopic astigmatism.

  18. The Role of Top-Down Focused Spatial Attention in Preattentive Salience Coding and Salience-based Attentional Capture.

    Bertleff, Sabine; Fink, Gereon R; Weidner, Ralph

    2016-08-01

    Selective visual attention requires an efficient coordination between top-down and bottom-up attention control mechanisms. This study investigated the behavioral and neural effects of top-down focused spatial attention on the coding of highly salient distractors and their tendency to capture attention. Combining spatial cueing with an irrelevant distractor paradigm revealed bottom-up based attentional capture only when attention was distributed across the whole search display, including the distractor location. Top-down focusing spatial attention on the target location abolished attentional capture of a salient distractor outside the current attentional focus. Functional data indicated that the missing capture effect was not based on diminished bottom-up salience signals at unattended distractor locations. Irrespectively of whether salient distractors occurred at attended or unattended locations, their presence enhanced BOLD signals at their respective spatial representation in early visual areas as well as in inferior frontal, superior parietal, and medial parietal cortex. Importantly, activity in these regions reflected the presence of a salient distractor rather than attentional capture per se. Moreover, successfully inhibiting attentional capture of a salient distractor at an unattended location further increased neural responses in medial parietal regions known to be involved in controlling spatial attentional shifts. Consequently, data provide evidence that top-down focused spatial attention prevents automatic attentional capture by supporting attentional control processes counteracting a spatial bias toward a salient distractor. PMID:27054402

  19. Issue Salience and the Domestic Legitimacy Demands of European Integration. The Cases of Britain and Germany

    Henrike Viehrig

    2008-04-01

    Full Text Available The salience of European issues to the general public is a major determinant of the domestic legitimacy demands that governments face when they devise their European policies. The higher the salience of these issues, the more restrictive will be the legitimacy demands that governments have to meet on the domestic level. Whereas the domestic legitimacy of European policy can rest on a permissive consensus among the public in cases of low issue salience, it requires the electorate’s explicit endorsement in cases of high issue salience. Polling data from Britain and Germany show that the salience of European issues is clearly higher in Britain than in Germany. We thus conclude that British governments face tougher domestic legitimacy demands when formulating their European policies than German governments. This may contribute to accounting for both countries’ different approaches to the integration process: Germany as a role model of a pro-integrationist member state and, in contrast, Britain as the eternal 'awkward partner'.

  20. Perceptual salience affects the contents of working memory during free-recollection of objects from natural scenes.

    Pedale, Tiziana; Santangelo, Valerio

    2015-01-01

    One of the most important issues in the study of cognition is to understand which are the factors determining internal representation of the external world. Previous literature has started to highlight the impact of low-level sensory features (indexed by saliency-maps) in driving attention selection, hence increasing the probability for objects presented in complex and natural scenes to be successfully encoded into working memory (WM) and then correctly remembered. Here we asked whether the probability of retrieving high-saliency objects modulates the overall contents of WM, by decreasing the probability of retrieving other, lower-saliency objects. We presented pictures of natural scenes for 4 s. After a retention period of 8 s, we asked participants to verbally report as many objects/details as possible of the previous scenes. We then computed how many times the objects located at either the peak of maximal or minimal saliency in the scene (as indexed by a saliency-map; Itti et al., 1998) were recollected by participants. Results showed that maximal-saliency objects were recollected more often and earlier in the stream of successfully reported items than minimal-saliency objects. This indicates that bottom-up sensory salience increases the recollection probability and facilitates the access to memory representation at retrieval, respectively. Moreover, recollection of the maximal- (but not the minimal-) saliency objects predicted the overall amount of successfully recollected objects: The higher the probability of having successfully reported the most-salient object in the scene, the lower the amount of recollected objects. These findings highlight that bottom-up sensory saliency modulates the current contents of WM during recollection of objects from natural scenes, most likely by reducing available resources to encode and then retrieve other (lower saliency) objects. PMID:25741266

  1. Perceptual salience affects the contents of working memory during free-recollection of objects from natural scenes

    Tiziana Pedale

    2015-02-01

    Full Text Available One of the most important issues in the study of cognition is to understand which are the factors determining internal representation of the external world. Previous literature has started to highlight the impact of low-level sensory features (indexed by saliency-maps in driving attention selection, hence increasing the probability for objects presented in complex and natural scenes to be successfully encoded into working memory(WM and then correctly remembered. Here we asked whether the probability of retrieving high-saliency objects modulates the overall contents of WM, by decreasing the probability of retrieving other, lower-saliency objects. We presented pictures of natural scenes for 4 secs. After a retention period of 8 secs, we asked participants to verbally report as many objects/details as possible of the previous scenes. We then computed how many times the objects located at either the peak of maximal or minimal saliency in the scene (as indexed by a saliency-map; Itti et al., 1998 were recollected by participants. Results showed that maximal-saliency objects were recollected more often and earlier in the stream of successfully reported items than minimal-saliency objects. This indicates that bottom-up sensory salience increases the recollection probability and facilitates the access to memory representation at retrieval, respectively. Moreover, recollection of the maximal- (but not the minimal- saliency objects predicted the overall amount of successfully recollected objects: The higher the probability of having successfully reported the most-salient object in the scene, the lower the amount of recollected objects. These findings highlight that bottom-up sensory saliency modulates the current contents of WM during recollection of objects from natural scenes, most likely by reducing available resources to encode and then retrieve other (lower saliency objects.

  2. Chromosome aberration assays in Allium

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  3. Effect of aberrations in vortex spatial filtering

    Sharma, Manoj Kumar; Joseph, Joby; Senthilkumaran, P.

    2012-11-01

    Edge enhancement is a very important operation in image processing and a spiral phase plate can be used as a radial Hilbert mask for isotropic edge enhancement. In this paper we analyze the effect of various Seidel aberrations on the performance of radial Hilbert mask or the vortex phase mask. The aberrated vortex phase mask is implemented optically with the help of a high resolution, spatial light modulator (SLM). It has also been shown that out of various aberrations astigmatism can introduce anisotropy in the Hilbert mask which causes selective edge enhancement.

  4. Mortality salience, martyrdom, and military might: the great satan versus the axis of evil.

    Pyszczynski, Tom; Abdollahi, Abdolhossein; Solomon, Sheldon; Greenberg, Jeff; Cohen, Florette; Weise, David

    2006-04-01

    Study 1 investigated the effect of mortality salience on support for martyrdom attacks among Iranian college students. Participants were randomly assigned to answer questions about either their own death or an aversive topic unrelated to death and then evaluated materials from fellow students who either supported or opposed martyrdom attacks against the United States. Whereas control participants preferred the student who opposed martyrdom, participants reminded of death preferred the student who supported martyrdom and indicated they were more likely to consider such activities themselves. Study 2 investigated the effect of mortality salience on American college students' support for extreme military interventions by American forces that could kill thousands of civilians. Mortality salience increased support for such measures among politically conservative but not politically liberal students. The roles of existential fear, cultural worldviews, and construing one's nation as pursing a heroic battle against evil in advocacy of violence were discussed. PMID:16513804

  5. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map

    Yihua Tan

    2015-09-01

    Full Text Available This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate.

  6. Neural Dynamics of Emotional Salience Processing in Response to Voices during the Stages of Sleep

    Chen, Chenyi; Sung, Jia-Ying; Cheng, Yawei

    2016-01-01

    Sleep has been related to emotional functioning. However, the extent to which emotional salience is processed during sleep is unknown. To address this concern, we investigated night sleep in healthy adults regarding brain reactivity to the emotionally (happily, fearfully) spoken meaningless syllables dada, along with correspondingly synthesized nonvocal sounds. Electroencephalogram (EEG) signals were continuously acquired during an entire night of sleep while we applied a passive auditory oddball paradigm. During all stages of sleep, mismatch negativity (MMN) in response to emotional syllables, which is an index for emotional salience processing of voices, was detected. In contrast, MMN to acoustically matching nonvocal sounds was undetected during Sleep Stage 2 and 3 as well as rapid eye movement (REM) sleep. Post-MMN positivity (PMP) was identified with larger amplitudes during Stage 3, and at earlier latencies during REM sleep, relative to wakefulness. These findings clearly demonstrated the neural dynamics of emotional salience processing during the stages of sleep. PMID:27378870

  7. The self salience model of other-to-self effects : Integrating principles of self-enhancement, complementarity, and imitation

    Stapel, DA; Van der Zee, KI

    2006-01-01

    In a series of studies the Self Salience Model of other-to-self effects is tested. This model posits that self-construal salience is all important determinant of whether other-to-self effects follow the principles of self-enhancement, imitation, or complementarity. Participants imagined interactions

  8. Toward isolating the role of dopamine in the acquisition of incentive salience attribution.

    Chow, Jonathan J; Nickell, Justin R; Darna, Mahesh; Beckmann, Joshua S

    2016-10-01

    Stimulus-reward learning has been heavily linked to the reward-prediction error learning hypothesis and dopaminergic function. However, some evidence suggests dopaminergic function may not strictly underlie reward-prediction error learning, but may be specific to incentive salience attribution. Utilizing a Pavlovian conditioned approach procedure consisting of two stimuli that were equally reward-predictive (both undergoing reward-prediction error learning) but functionally distinct in regard to incentive salience (levers that elicited sign-tracking and tones that elicited goal-tracking), we tested the differential role of D1 and D2 dopamine receptors and nucleus accumbens dopamine in the acquisition of sign- and goal-tracking behavior and their associated conditioned reinforcing value within individuals. Overall, the results revealed that both D1 and D2 inhibition disrupted performance of sign- and goal-tracking. However, D1 inhibition specifically prevented the acquisition of sign-tracking to a lever, instead promoting goal-tracking and decreasing its conditioned reinforcing value, while neither D1 nor D2 signaling was required for goal-tracking in response to a tone. Likewise, nucleus accumbens dopaminergic lesions disrupted acquisition of sign-tracking to a lever, while leaving goal-tracking in response to a tone unaffected. Collectively, these results are the first evidence of an intraindividual dissociation of dopaminergic function in incentive salience attribution from reward-prediction error learning, indicating that incentive salience, reward-prediction error, and their associated dopaminergic signaling exist within individuals and are stimulus-specific. Thus, individual differences in incentive salience attribution may be reflective of a differential balance in dopaminergic function that may bias toward the attribution of incentive salience, relative to reward-prediction error learning only. PMID:27371135

  9. Structural integrity of the limbic-prefrontal connection: Neuropathological correlates of anxiety in Williams syndrome.

    Ng, Rowena; Brown, Timothy T; Järvinen, Anna M; Erhart, Matthew; Korenberg, Julie R; Bellugi, Ursula; Halgren, Eric

    2016-01-01

    Williams syndrome (WS) is a genetic condition characterized by a hypersocial personality and desire to form close relationships, juxtaposed with significant anxieties of nonsocial events. The neural underpinnings of anxiety in individuals with WS are currently unknown. Aberrations in the anatomical and microstructural integrity of the uncinate fasciculus (UF) have been recently implicated in social and generalized anxiety disorders. Based on these findings, we tested the hypothesis that the reported anxieties in individuals with WS share similar neuropathological correlates. Toward this end, diffusion tensor imaging (DTI) methods were employed to examine the microstructural integrity (fractional anisotropy, mean diffusivity, longitudinal diffusivity) of the UF in 18 WS and 15 typically developing adults (TD). Anxiety and sociability questionnaires were administered to determine associations with DTI indices of UF across groups. Results revealed comparable white matter integrity of the UF across groups, yet elevated subjective experience of anxiety in those with WS. Additionally, sociability and UF microstructural properties were dissociated across both groups. Whereas no relationships were found between DTI indices and anxiety in TD participants, strong negative associations were observed between these constructs in individuals with WS. Findings indicated that increased anxiety manifested by individuals with WS was associated with DTI measures of the UF and may signal structural or possibly physiological aberration involving this tract within the prefrontal-temporal network. PMID:26214361

  10. Multi-scale mesh saliency with local adaptive patches for viewpoint selection

    Nouri, Anass; Charrier, Christophe; Lézoray, Olivier

    2015-01-01

    International audience Our visual attention is attracted by specific areas into 3D objects (represented by meshes). This visual attention depends on the degree of saliency exposed by these areas. In this paper, we propose a novel multi-scale approach for detecting salient regions. To do so, we define a local surface descriptor based on patches of adaptive size and filled in with a local height field. The single-scale saliency of a vertex is defined as its degree measure in the mesh with ed...

  11. Perspectives on the Salience and Magnitude of Dam Impacts for Hydro Development Scenarios in China

    Desiree Tullos

    2010-06-01

    Survey results indicate differences in the perceived salience and magnitude of impacts across both expert groups and dam scenarios. Furthermore, surveys indicate that stakeholder perceptions changed as the information provided regarding dam impacts became more specific, suggesting that stakeholder evaluation may be influenced by quality of information. Finally, qualitative comments from the survey reflect some of the challenges of interdisciplinary dam assessment, including cross-disciplinary cooperation, data standardisation and weighting, and the distribution and potential mitigation of impacts. Given the complexity of data and perceptions around dam impacts, decision-support tools that integrate the objective magnitude and perceived salience of impacts are required urgently.

  12. An Improved Model of Producing Saliency Map for Visual Attention System

    Huang, Jingang; Kong, Bin; Cheng, Erkang; Zheng, Fei

    The iLab Neuromorphic Vision Toolkit (iINVT), steadily kept up to date by the group around Laurent Itti, is one of the currently best known attention systems. Their model of bottom up or saliency-based visual attention as well as their implementation serves as a basis for many research groups. How to combine the feature maps finally into the saliency map is a key point for this kind of visual attention system. We modified the original model of Laurent Itti to make it more corresponding with our perception.

  13. Aberration corrected Lorentz scanning transmission electron microscopy

    We present results from an aberration corrected scanning transmission electron microscope which has been customised for high resolution quantitative Lorentz microscopy with the sample located in a magnetic field free or low field environment. We discuss the innovations in microscope instrumentation and additional hardware that underpin the imaging improvements in resolution and detection with a focus on developments in differential phase contrast microscopy. Examples from materials possessing nanometre scale variations in magnetisation illustrate the potential for aberration corrected Lorentz imaging as a tool to further our understanding of magnetism on this lengthscale. - Highlights: • Demonstration of nanometre scale resolution in magnetic field free environment using aberration correction in the scanning transmission electron microscope (STEM). • Implementation of differential phase contrast mode of Lorentz microscopy in aberration corrected STEM with improved sensitivity. • Quantitative imaging of magnetic induction of nanostructures in amorphous and cross-section samples

  14. Aberration features in directional dark matter detection

    Bozorgnia, Nassim; Gondolo, Paolo

    2012-01-01

    The motion of the Earth around the Sun causes an annual change in the magnitude and direction of the arrival velocity of dark matter particles on Earth, in a way analogous to aberration of stellar light. In directional detectors, aberration of weakly interacting massive particles (WIMPs) modulates the pattern of nuclear recoil directions in a way that depends on the orbital velocity of the Earth and the local galactic distribution of WIMP velocities. Knowing the former, WIMP aberration can give information on the latter, besides being a curious way of confirming the revolution of the Earth and the extraterrestrial provenance of WIMPs. While observing the full aberration pattern requires extremely large exposures, we claim that the annual variation of the mean recoil direction or of the event counts over specific solid angles may be detectable with moderately large exposures. For example, integrated counts over galactic hemispheres separated by planes perpendicular to Earth's orbit would modulate annually, res...

  15. Catadioptric aberration correction in cathode lens microscopy

    Tromp, R.M. [IBM T.J. Watson Research Center, PO Box 218, Yorktown Heights, NY 10598 (United States); Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Niels Bohrweg 2, 2333 CA Leiden (Netherlands)

    2015-04-15

    In this paper I briefly review the use of electrostatic electron mirrors to correct the aberrations of the cathode lens objective lens in low energy electron microscope (LEEM) and photo electron emission microscope (PEEM) instruments. These catadioptric systems, combining electrostatic lens elements with a reflecting mirror, offer a compact solution, allowing simultaneous and independent correction of both spherical and chromatic aberrations. A comparison with catadioptric systems in light optics informs our understanding of the working principles behind aberration correction with electron mirrors, and may point the way to further improvements in the latter. With additional developments in detector technology, 1 nm spatial resolution in LEEM appears to be within reach. - Highlights: • The use of electron mirrors for aberration correction in LEEM/PEEM is reviewed. • A comparison is made with similar systems in light optics. • Conditions for 1 nm spatial resolution are discussed.

  16. Catadioptric aberration correction in cathode lens microscopy

    In this paper I briefly review the use of electrostatic electron mirrors to correct the aberrations of the cathode lens objective lens in low energy electron microscope (LEEM) and photo electron emission microscope (PEEM) instruments. These catadioptric systems, combining electrostatic lens elements with a reflecting mirror, offer a compact solution, allowing simultaneous and independent correction of both spherical and chromatic aberrations. A comparison with catadioptric systems in light optics informs our understanding of the working principles behind aberration correction with electron mirrors, and may point the way to further improvements in the latter. With additional developments in detector technology, 1 nm spatial resolution in LEEM appears to be within reach. - Highlights: • The use of electron mirrors for aberration correction in LEEM/PEEM is reviewed. • A comparison is made with similar systems in light optics. • Conditions for 1 nm spatial resolution are discussed

  17. Ventromedial prefrontal cortex mediates visual attention during facial emotion recognition

    Wolf, Richard C.; Philippi, Carissa L.; Motzkin, Julian C.; Baskaya, Mustafa K.; Koenigs, Michael

    2014-01-01

    The ventromedial prefrontal cortex plays a crucial role in regulating emotion and social behavior, yet the precise mechanisms underlying this function remain unclear. Using eye-tracking in patients with brain lesions, Wolf et al. show that ventromedial prefrontal cortex is critical for directing visual attention during facial emotion recognition.

  18. Sensing Phase Aberrations behind Lyot Coronagraphs

    Sivaramakrishnan, Anand; Soummer, Rémi; Pueyo, Laurent; Wallace, J. Kent; Shao, Michael

    2008-11-01

    Direct detection of young extrasolar planets orbiting nearby stars can be accomplished from the ground with extreme adaptive optics and coronagraphy in the near-infrared, as long as this combination can provide an image with a dynamic range of 107 after the data are processed. Slowly varying speckles due to residual phase aberrations that are not measured by the primary wave-front sensor are the primary obstacle to achieving such a dynamic range. In particular, non-common optical path aberrations occurring between the wave-front sensor and the coronagraphic occulting spot degrade performance the most. We analyze the passage of both low and high spatial frequency phase ripples, as well as low-order Zernike aberrations, through an apodized pupil Lyot coronagraph in order to demonstrate the way coronagraphic filtering affects various aberrations. We derive the coronagraphically induced cutoff frequency of the filtering and estimate coronagraphic contrast losses due to low-order Zernike aberrations: tilt, astigmatism, defocus, coma, and spherical aberration. Such slowly varying path errors can be measured behind a coronagraph and corrected by a slowly updated optical path delay precompensation or offset asserted on the wave front by the adaptive optics (AO) system. We suggest ways of measuring and correcting all but the lowest spatial frequency aberrations using Lyot plane wave-front data, in spite of the complex interaction between the coronagraph and those mid-spatial frequency aberrations that cause image plane speckles near the coronagraphic focal plane mask occulter's edge. This investigation provides guidance for next-generation coronagraphic instruments currently under construction.

  19. Aberrant right hepatic artery; A case report

    We present a rare case of aberrant hepatic artery in a 40-year-old male with a history of chronic cholecystitis. During laparoscopic surgery, the artery found to pass anterior to the body the gallbladder and bifurcating anterior to the gallbladder body. The surgery was un eventful. We present this anomaly of the rare condition of aberrant right hepatic artery which should be in mind during laparoscopic cholecystectomy, because inadverant injury could lead to massive bleeding and increase co morbidities. (author)

  20. Electrophysiological mapping of novel prefrontal - cerebellar pathways

    Matthew W Jones

    2009-08-01

    Full Text Available Whilst the cerebellum is predominantly considered a sensorimotor control structure, accumulating evidence suggests that it may also subserve non motor functions during cognition. However, this possibility is not universally accepted, not least because the nature and pattern of links between higher cortical structures and the cerebellum are poorly characterized. We have therefore used in vivo electrophysiological methods in anaesthetized rats to directly investigate connectivity between the medial prefrontal cortex (prelimbic subdivision, PrL and the cerebellum. Stimulation of deep layers of PrL evoked distinct field potentials in the cerebellar cortex with a mean latency to peak of approximately 35ms. These responses showed a well-defined topography, and were maximal in lobule VII of the contralateral vermis (a known oculomotor centre; they were not attenuated by local anesthesia of the overlying M2 motor cortex, though M2 stimulation did evoke field potentials in lobule VII with a shorter latency. Single-unit recordings showed that prelimbic cortical stimulation elicits complex spikes in lobule VII Purkinje cells, indicating transmission via a previously undescribed cerebro-olivocerebellar pathway. Our results therefore establish a physiological basis for communication between PrL and the cerebellum. The role(s of this pathway remain to be resolved, but presumably relate to control of eye movements and/or distributed networks associated with integrated prefrontal cortical functions.

  1. Individual Variation in the Propensity to Attribute Incentive Salience to an Appetitive Cue Predicts the Propensity to Attribute Motivational Salience to an Aversive Cue

    Morrow, Jonathan D.; Maren, Stephen; ROBINSON, TERRY E.

    2011-01-01

    It has been proposed that animals that attribute high levels of incentive salience to reward-related cues may be especially vulnerable to addiction. Individual variation has also been observed in the motivational value attributed to aversive cues, which may confer vulnerability to anxiety disorders such as post-traumatic stress disorder (PTSD). There may be a core behavioral trait that contributes to individual variation in the motivational value assigned to predictive cues regardless of emot...

  2. Lucid dreaming and ventromedial versus dorsolateral prefrontal task performance.

    Neider, Michelle; Pace-Schott, Edward F; Forselius, Erica; Pittman, Brian; Morgan, Peter T

    2011-06-01

    Activity in the prefrontal cortex may distinguish the meta-awareness experienced during lucid dreams from its absence in normal dreams. To examine a possible relationship between dream lucidity and prefrontal task performance, we carried out a prospective study in 28 high school students. Participants performed the Wisconsin Card Sort and Iowa Gambling tasks, then for 1 week kept dream journals and reported sleep quality and lucidity-related dream characteristics. Participants who exhibited a greater degree of lucidity performed significantly better on the task that engages the ventromedial prefrontal cortex (the Iowa Gambling Task), but degree of lucidity achieved did not distinguish performance on the task that engages the dorsolateral prefrontal cortex (the Wisconsin Card Sort Task), nor did it distinguish self-reported sleep quality or baseline characteristics. The association between performance on the Iowa Gambling Task and lucidity suggests a connection between lucid dreaming and ventromedial prefrontal function. PMID:20829072

  3. Basal forebrain motivational salience signal enhances cortical processing and decision speed

    Sylvina M Raver

    2015-10-01

    Full Text Available The basal forebrain (BF contains major projections to the cerebral cortex, and plays a well-documented role in arousal, attention, decision-making, and in modulating cortical activity. BF neuronal degeneration is an early event in Alzheimer’s disease and dementias, and occurs in normal cognitive aging. While the BF is best known for its population of cortically projecting cholinergic neurons, the region is anatomically and neurochemically diverse, and also contains prominent populations of non-cholinergic projection neurons. In recent years, increasing attention has been dedicated to these non-cholinergic BF neurons in order to better understand how non-cholinergic BF circuits control cortical processing and behavioral performance. In this review, we focus on a unique population of putative non-cholinergic BF neurons that encodes the motivational salience of stimuli with a robust ensemble bursting response. We review recent studies that describe the specific physiological and functional characteristics of these BF salience-encoding neurons in behaving animals. These studies support the unifying hypothesis whereby BF salience-encoding neurons act as a gain modulation mechanism of the decision-making process to enhance cortical processing of behaviorally relevant stimuli, and thereby facilitate faster and more precise behavioral responses. This function of BF salience-encoding neurons represents a critical component in determining which incoming stimuli warrant an animal’s attention, and is therefore a fundamental and early requirement of behavioral flexibility.

  4. Dual Low-Rank Pursuit: Learning Salient Features for Saliency Detection.

    Lang, Congyan; Feng, Jiashi; Feng, Songhe; Wang, Jingdong; Yan, Shuicheng

    2016-06-01

    Saliency detection is an important procedure for machines to understand visual world as humans do. In this paper, we consider a specific saliency detection problem of predicting human eye fixations when they freely view natural images, and propose a novel dual low-rank pursuit (DLRP) method. DLRP learns saliency-aware feature transformations by utilizing available supervision information and constructs discriminative bases for effectively detecting human fixation points under the popular low-rank and sparsity-pursuit framework. Benefiting from the embedded high-level information in the supervised learning process, DLRP is able to predict fixations accurately without performing the expensive object segmentation as in the previous works. Comprehensive experiments clearly show the superiority of the proposed DLRP method over the established state-of-the-art methods. We also empirically demonstrate that DLRP provides stronger generalization performance across different data sets and inherits the advantages of both the bottom-up- and top-down-based saliency detection methods. PMID:27046853

  5. Two-scale image fusion of visible and infrared images using saliency detection

    Bavirisetti, Durga Prasad; Dhuli, Ravindra

    2016-05-01

    Military, navigation and concealed weapon detection need different imaging modalities such as visible and infrared to monitor a targeted scene. These modalities provide complementary information. For better situation awareness, complementary information of these images has to be integrated into a single image. Image fusion is the process of integrating complementary source information into a composite image. In this paper, we propose a new image fusion method based on saliency detection and two-scale image decomposition. This method is beneficial because the visual saliency extraction process introduced in this paper can highlight the saliency information of source images very well. A new weight map construction process based on visual saliency is proposed. This process is able to integrate the visually significant information of source images into the fused image. In contrast to most of the multi-scale image fusion techniques, proposed technique uses only two-scale image decomposition. So it is fast and efficient. Our method is tested on several image pairs and is evaluated qualitatively by visual inspection and quantitatively using objective fusion metrics. Outcomes of the proposed method are compared with the state-of-art multi-scale fusion techniques. Results reveal that the proposed method performance is comparable or superior to the existing methods.

  6. Isolating the Incentive Salience of Reward-Associated Stimuli: Value, Choice, and Persistence

    Beckmann, Joshua S.; Chow, Jonathan J.

    2015-01-01

    Sign- and goal-tracking are differentially associated with drug abuse-related behavior. Recently, it has been hypothesized that sign- and goal-tracking behavior are mediated by different neurobehavioral valuation systems, including differential incentive salience attribution. Herein, we used different conditioned stimuli to preferentially elicit…

  7. Subjective and Objective Parameters Determining "Salience" in Long-Term Dialect Accommodation.

    Auer, Peter; Barden, Birgit; Grosskopf, Beate

    1998-01-01

    Presents results of a longitudinal study on long-term dialect accommodation in a German dialect setting. An important model of explaining which linguistic structures undergo such convergence and which do not makes use of the notion of "salience." (Author/VWL)

  8. Movement or Goal: Goal Salience and Verbal Cues Affect Preschoolers' Imitation of Action Components

    Elsner, Birgit; Pfeifer, Caroline

    2012-01-01

    The impact of goal salience and verbal cues given by the model on 3- to 5-year-olds' reproduction of action components (movement or goal) was investigated in an imitation choice task. Preschoolers watched an experimenter moving a puppet up or down a ramp, terminating at one of two target objects. The target objects were either differently colored…

  9. The Development of Visual Search in Infancy: Attention to Faces versus Salience

    Kwon, Mee-Kyoung; Setoodehnia, Mielle; Baek, Jongsoo; Luck, Steven J.; Oakes, Lisa M.

    2016-01-01

    Four experiments examined how faces compete with physically salient stimuli for the control of attention in 4-, 6-, and 8-month-old infants (N = 117 total). Three computational models were used to quantify physical salience. We presented infants with visual search arrays containing a face and familiar object(s), such as shoes and flowers. Six- and…

  10. Relative Saliency in Change Signals Affects Perceptual Comparison and Decision Processes in Change Detection

    Yang, Cheng-Ta

    2011-01-01

    Change detection requires perceptual comparison and decision processes on different features of multiattribute objects. How relative salience between two feature-changes influences the processes has not been addressed. This study used the systems factorial technology to investigate the processes when detecting changes in a Gabor patch with visual…

  11. Fusion of infrared and visible images based on saliency scale-space in frequency domain

    Chen, Yanfei; Sang, Nong; Dan, Zhiping

    2015-12-01

    A fusion algorithm of infrared and visible images based on saliency scale-space in the frequency domain was proposed. Focus of human attention is directed towards the salient targets which interpret the most important information in the image. For the given registered infrared and visible images, firstly, visual features are extracted to obtain the input hypercomplex matrix. Secondly, the Hypercomplex Fourier Transform (HFT) is used to obtain the salient regions of the infrared and visible images respectively, the convolution of the input hypercomplex matrix amplitude spectrum with a low-pass Gaussian kernel of an appropriate scale which is equivalent to an image saliency detector are done. The saliency maps are obtained by reconstructing the 2D signal using the original phase and the amplitude spectrum, filtered at a scale selected by minimizing saliency map entropy. Thirdly, the salient regions are fused with the adoptive weighting fusion rules, and the nonsalient regions are fused with the rule based on region energy (RE) and region sharpness (RS), then the fused image is obtained. Experimental results show that the presented algorithm can hold high spectrum information of the visual image, and effectively get the thermal targets information at different scales of the infrared image.

  12. Rigid Registration of Renal Perfusion Images Using a Neurobiology-Based Visual Saliency Model

    Mahapatra Dwarikanath

    2010-01-01

    Full Text Available General mutual information- (MI- based registration methods treat all voxels equally. But each voxel has a different utility depending upon the task. Because of its robustness to noise, low computation time, and agreement with human fixations, the Itti-Koch visual saliency model is used to determine voxel utility of renal perfusion data. The model is able to match identical regions in spite of intensity change due to its close adherence to the center-surround property of the visual cortex. Saliency value is used as a pixel's utility measure in an MI framework for rigid registration of renal perfusion data exhibiting rapid intensity change and noise. We simulated varying degrees of rotation and translation motion under different noise levels, and a novel optimization technique was used for fast and accurate recovery of registration parameters. We also registered real patient data having rotation and translation motion. Our results show that saliency information improves registration accuracy for perfusion images and the Itti-Koch model is a better indicator of visual saliency than scale-space maps.

  13. Advert saliency distracts children's visual attention during task-oriented internet use

    Nils eHolmberg

    2014-02-01

    Full Text Available The general research question of the present study was to assess the impact of visually salient online adverts on children's task-oriented internet use. In order to answer this question, an experimental study was constructed in which 9-year-old and 12-year-old Swedish children were asked to solve a number of tasks while interacting with a mockup website. In each trial, web adverts in several saliency conditions were presented. By both measuring children's task accuracy, as well as the visual processing involved in solving these tasks, this study allows us to infer how two types of visual saliency affect children's attentional behavior, and whether such behavioral effects also impacts their task performance. Analyses show that low-level visual features and task relevance in online adverts have different effects on performance measures and process measures respectively. Whereas task performance is stable with regard to several advert saliency conditions, a marked effect is seen on children's gaze behavior. On the other hand, task performance is shown to be more sensitive to individual differences such as age, gender and level of gaze control. The results provide evidence about cognitive and behavioral distraction effects in children's task-oriented internet use caused by visual saliency in online adverts. The experiment suggests that children to some extent are able to compensate for behavioral effects caused by distracting visual stimuli when solving prospective memory tasks. Suggestions are given for further research into the interdiciplinary area between media research and cognitive science.

  14. A Comparison between Element Salience versus Context as Item Difficulty Factors in Raven's Matrices

    Perez-Salas, Claudia P.; Streiner, David L.; Roberts, Maxwell J.

    2012-01-01

    The nature of contextual facilitation effects for items derived from Raven's Progressive Matrices was investigated in two experiments. For these, the original matrices were modified, creating either abstract versions with high element salience, or versions which comprised realistic entities set in familiar contexts. In order to replicate and…

  15. Researcher Effects on Mortality Salience Research: A Meta-Analytic Moderator Analysis

    Yen, Chih-Long; Cheng, Chung-Ping

    2013-01-01

    A recent meta-analysis of 164 terror management theory (TMT) papers indicated that mortality salience (MS) yields substantial effects (r = 0.35) on worldview and self-esteem-related dependent variables (B. L. Burke, A. Martens, & E. H. Faucher, 2010). This study reanalyzed the data to explore the researcher effects of TMT. By cluster-analyzing…

  16. Active Teaching Strategies for a Sense of Salience: End-of-Life Communication

    Kopp, Mary L.

    2013-01-01

    This study compared active teaching strategies with passive lecture by evaluating cognitive, affective, and psychomotor learning outcomes, while highlighting end-of-life communication in nursing education. The problem addressed was twofold: First, passive lecture prevents transfer to situational decision-making, or a sense of salience (Benner,…

  17. Bottom-Up Visual Saliency Estimation With Deep Autoencoder-Based Sparse Reconstruction.

    Xia, Chen; Qi, Fei; Shi, Guangming

    2016-06-01

    Research on visual perception indicates that the human visual system is sensitive to center-surround (C-S) contrast in the bottom-up saliency-driven attention process. Different from the traditional contrast computation of feature difference, models based on reconstruction have emerged to estimate saliency by starting from original images themselves instead of seeking for certain ad hoc features. However, in the existing reconstruction-based methods, the reconstruction parameters of each area are calculated independently without taking their global correlation into account. In this paper, inspired by the powerful feature learning and data reconstruction ability of deep autoencoders, we construct a deep C-S inference network and train it with the data sampled randomly from the entire image to obtain a unified reconstruction pattern for the current image. In this way, global competition in sampling and learning processes can be integrated into the nonlocal reconstruction and saliency estimation of each pixel, which can achieve better detection results than the models with separate consideration on local and global rarity. Moreover, by learning from the current scene, the proposed model can achieve the feature extraction and interaction simultaneously in an adaptive way, which can form a better generalization ability to handle more types of stimuli. Experimental results show that in accordance with different inputs, the network can learn distinct basic features for saliency modeling in its code layer. Furthermore, in a comprehensive evaluation on several benchmark data sets, the proposed method can outperform the existing state-of-the-art algorithms. PMID:26800552

  18. Advert saliency distracts children's visual attention during task-oriented internet use.

    Holmberg, Nils; Sandberg, Helena; Holmqvist, Kenneth

    2014-01-01

    The general research question of the present study was to assess the impact of visually salient online adverts on children's task-oriented internet use. In order to answer this question, an experimental study was constructed in which 9- and 12-year-old Swedish children were asked to solve a number of tasks while interacting with a mockup website. In each trial, web adverts in several saliency conditions were presented. By both measuring children's task accuracy, as well as the visual processing involved in solving these tasks, this study allows us to infer how two types of visual saliency affect children's attentional behavior, and whether such behavioral effects also impacts their task performance. Analyses show that low-level visual features and task relevance in online adverts have different effects on performance measures and process measures respectively. Whereas task performance is stable with regard to several advert saliency conditions, a marked effect is seen on children's gaze behavior. On the other hand, task performance is shown to be more sensitive to individual differences such as age, gender and level of gaze control. The results provide evidence about cognitive and behavioral distraction effects in children's task-oriented internet use caused by visual saliency in online adverts. The experiment suggests that children to some extent are able to compensate for behavioral effects caused by distracting visual stimuli when solving prospective memory tasks. Suggestions are given for further research into the interdiciplinary area between media research and cognitive science. PMID:24575057

  19. Political mobilization of Dutch Muslims : religious identity salience, goal framing and normative constraints

    Phalet, Karen; Baysu, Gülseli

    2010-01-01

    This article addresses the question of when and for what purpose Muslims will act collectively in the political arena. The impact of religious identity salience, goal framing, and normative constraints on political mobilization was examined in two Muslim communities with different group positions in

  20. Learning-Based Visual Saliency Model for Detecting Diabetic Macular Edema in Retinal Image.

    Zou, Xiaochun; Zhao, Xinbo; Yang, Yongjia; Li, Na

    2016-01-01

    This paper brings forth a learning-based visual saliency model method for detecting diagnostic diabetic macular edema (DME) regions of interest (RoIs) in retinal image. The method introduces the cognitive process of visual selection of relevant regions that arises during an ophthalmologist's image examination. To record the process, we collected eye-tracking data of 10 ophthalmologists on 100 images and used this database as training and testing examples. Based on analysis, two properties (Feature Property and Position Property) can be derived and combined by a simple intersection operation to obtain a saliency map. The Feature Property is implemented by support vector machine (SVM) technique using the diagnosis as supervisor; Position Property is implemented by statistical analysis of training samples. This technique is able to learn the preferences of ophthalmologist visual behavior while simultaneously considering feature uniqueness. The method was evaluated using three popular saliency model evaluation scores (AUC, EMD, and SS) and three quality measurements (classical sensitivity, specificity, and Youden's J statistic). The proposed method outperforms 8 state-of-the-art saliency models and 3 salient region detection approaches devised for natural images. Furthermore, our model successfully detects the DME RoIs in retinal image without sophisticated image processing such as region segmentation. PMID:26884750

  1. Learning-Based Visual Saliency Model for Detecting Diabetic Macular Edema in Retinal Image

    Xiaochun Zou

    2016-01-01

    Full Text Available This paper brings forth a learning-based visual saliency model method for detecting diagnostic diabetic macular edema (DME regions of interest (RoIs in retinal image. The method introduces the cognitive process of visual selection of relevant regions that arises during an ophthalmologist’s image examination. To record the process, we collected eye-tracking data of 10 ophthalmologists on 100 images and used this database as training and testing examples. Based on analysis, two properties (Feature Property and Position Property can be derived and combined by a simple intersection operation to obtain a saliency map. The Feature Property is implemented by support vector machine (SVM technique using the diagnosis as supervisor; Position Property is implemented by statistical analysis of training samples. This technique is able to learn the preferences of ophthalmologist visual behavior while simultaneously considering feature uniqueness. The method was evaluated using three popular saliency model evaluation scores (AUC, EMD, and SS and three quality measurements (classical sensitivity, specificity, and Youden’s J statistic. The proposed method outperforms 8 state-of-the-art saliency models and 3 salient region detection approaches devised for natural images. Furthermore, our model successfully detects the DME RoIs in retinal image without sophisticated image processing such as region segmentation.

  2. Reconciling Saliency and Object Center-Bias Hypotheses in Explaining Free-Viewing Fixations.

    Borji, Ali; Tanner, James

    2016-06-01

    Predicting where people look in natural scenes has attracted a lot of interest in computer vision and computational neuroscience over the past two decades. Two seemingly contrasting categories of cues have been proposed to influence where people look: 1) low-level image saliency and 2) high-level semantic information. Our first contribution is to take a detailed look at these cues to confirm the hypothesis proposed by Henderson and Nuthmann and Henderson that observers tend to look at the center of objects. We analyzed fixation data for scene free-viewing over 17 observers on 60 object-annotated images with various types of objects. Images contained different types of scenes, such as natural scenes, line drawings, and 3-D rendered scenes. Our second contribution is to propose a simple combined model of low-level saliency and object center bias that outperforms each individual component significantly over our data, as well as on the Object and Semantic Images and Eye-tracking data set by Xu et al. The results reconcile saliency with object center-bias hypotheses and highlight that both types of cues are important in guiding fixations. Our work opens new directions to understand strategies that humans use in observing scenes and objects, and demonstrates the construction of combined models of low-level saliency and high-level object-based information. PMID:26452292

  3. Color Entrenchment in Middle-School English Speakers: Cognitive Salience Index Applied to Color Listing

    Jodi L. Sandford

    2016-06-01

    Full Text Available This study presents results of two questionnaires posed to English speaking middle-school students to verify the level of color term entrenchment and color prototypes at the age of 12. The methods included color listing and informant introspection on a color prototype linguistic construction. Listing techniques have long been used to identify basic categories and prototypically relevant linguistic items. In this case Sutrop’s Cognitive Salience Index (2001 served to reveal the facilitation of retrieval of concepts in long-term memory thus allowing us to evince the degree of entrenchment and salience of the given color term. Participant introspection in conjunction with conceptual salience analysis (Talmy 2000, 2005 regarding prototypical items (Rosch 1975, 1978, 1983 was also employed to identify what items are actually associated prototypically with colors at this age. The results are compared to adult color listings and prototypes (for both English and Italian speakers. Divergence is significant both in regard to the Cognitive Salience Index and within group judgment of the color prototypes. Further details about the subordinate color term choices and the agreement on prototypes reveal the conventionalized linguistic color associations made by this specific group of north-west American middle-school students.

  4. Defensive or Existential Religious Orientations and Mortality Salience Hypothesis: Using Conservatism as a Dependent Measure

    Koca-Atabey, Mujde; Oner-Ozkan, Bengi

    2011-01-01

    The study examined the relationship between the defensive versus existential religious orientation and mortality salience hypothesis in a country where the predominant type of religion is Islam. It was predicted that the mortality reactions of participants would not differ in accordance with their religious orientations within a Muslim sample. The…

  5. Perceptual Salience and Reward Both Influence Feedback-Related Neural Activity Arising from Choice.

    Lou, Bin; Hsu, Wha-Yin; Sajda, Paul

    2015-09-23

    For day-to-day decisions, multiple factors influence our choice between alternatives. Two dimensions of decision making that substantially affect choice are the objective perceptual properties of the stimulus (e.g., salience) and its subjective value. Here we measure EEGs in human subjects to relate their feedback-evoked EEG responses to estimates of prediction error given a neurally derived expected value for each trial. Unlike in traditional reinforcement learning paradigms, in our experiment the reward itself is not probabilistic; rather, it is a fixed value, which, when combined with the variable stimulus salience, yields uncertainty in the choice. We find that feedback-evoked event-related potentials (ERPs), specifically those classically termed feedback-related negativity, are modulated by both the reward level and stimulus salience. Using single-trial analysis of the EEG, we show stimulus-locked EEG components reflecting perceived stimulus salience can be combined with the level of reward to create an estimate of expected reward. This expected reward is used to form a prediction error that correlates with the trial-by-trial variability of the feedback ERPs for negative, but not positive, feedback. This suggests that the valence of prediction error is more important than the valence of the actual feedback, since only positive rewards were delivered in the experiment (no penalty or loss). Finally, we show that these subjectively defined prediction errors are informative of the riskiness of the subject's choice on the subsequent trial. In summary, our work shows that neural correlates of stimulus salience interact with value information to yield neural representations of subjective expected reward. Significance statement: How we make perceptual decisions depends on sensory evidence and the value of our options. These two factors often interact to yield subjective decisions; i.e., individuals integrate sensory evidence and value to form their own estimates of

  6. Amygdala-prefrontal pathways and the dopamine system affect nociceptive responses in the prefrontal cortex

    Onozawa Kitaro; Yagasaki Yuki; Izawa Yumi; Abe Hiroyuki; Kawakami Yoriko

    2011-01-01

    Abstract Background We previously demonstrated nociceptive discharges to be evoked by mechanical noxious stimulation in the prefrontal cortex (PFC). The nociceptive responses recorded in the PFC are conceivably involved in the affective rather than the sensory-discriminative dimension of pain. The PFC receives dense projection from the limbic system. Monosynaptic projections from the basolateral nucleus of the amygdala (BLA) to the PFC are known to produce long-lasting synaptic plasticity. We...

  7. Modeling eye movements in visual agnosia with a saliency map approach: bottom-up guidance or top-down strategy?

    Foulsham, Tom; Barton, Jason J S; Kingstone, Alan; Dewhurst, Richard; Underwood, Geoffrey

    2011-08-01

    Two recent papers (Foulsham, Barton, Kingstone, Dewhurst, & Underwood, 2009; Mannan, Kennard, & Husain, 2009) report that neuropsychological patients with a profound object recognition problem (visual agnosic subjects) show differences from healthy observers in the way their eye movements are controlled when looking at images. The interpretation of these papers is that eye movements can be modeled as the selection of points on a saliency map, and that agnosic subjects show an increased reliance on visual saliency, i.e., brightness and contrast in low-level stimulus features. Here we review this approach and present new data from our own experiments with an agnosic patient that quantifies the relationship between saliency and fixation location. In addition, we consider whether the perceptual difficulties of individual patients might be modeled by selectively weighting the different features involved in a saliency map. Our data indicate that saliency is not always a good predictor of fixation in agnosia: even for our agnosic subject, as for normal observers, the saliency-fixation relationship varied as a function of the task. This means that top-down processes still have a significant effect on the earliest stages of scanning in the setting of visual agnosia, indicating severe limitations for the saliency map model. Top-down, active strategies-which are the hallmark of our human visual system-play a vital role in eye movement control, whether we know what we are looking at or not. PMID:21316191

  8. The dorsolateral prefrontal cortex, schizophrenia and PET

    Central neurophysiology can be measured with PET. These measurements are providing insights into the regional abnormalities associated with schizophrenia. Cohorts of schizophrenic subjects have been studied cross-sectionally in attempts to identify common regional deficits. More recently the advent of fast dynamic measurements of regional cerebral blood flow have allowed rapid serial measurements in the same subject in different brain states (activation studies). These complementary approaches are based upon, and are interpreted with reference to, a number of methodological considerations and underlying hypotheses. The key hypotheses underpining cross-sectional and activation studies are discussed within the framework of the lesion model and functional anatomy models of brain function. This brief review of some assumptions, ideas and methodological constraints is illustrated with empirical data implicating the dorsolateral prefrontal cortex in schizophrenic symptoms. (author)

  9. Withholding response in the face of a smile: age-related differences in prefrontal sensitivity to Nogo cues following happy and angry faces.

    Todd, Rebecca M; Lee, Wayne; Evans, Jennifer W; Lewis, Marc D; Taylor, Margot J

    2012-07-01

    The modulation of control processes by stimulus salience, as well as associated neural activation, changes over development. We investigated age-related differences in the influence of facial emotion on brain activation when an action had to be withheld, focusing on a developmental period characterized by rapid social-emotional and cognitive change. Groups of kindergarten and young school-aged children and a group of young adults performed a modified Go/Nogo task. Response cues were preceded by happy or angry faces. After controlling for task performance, left orbitofrontal regions discriminated trials with happy vs. angry faces in children but not in adults when a response was withheld, and this effect decreased parametrically with age group. Age-related changes in prefrontal responsiveness to facial expression were not observed when an action was required, nor did this region show age-related activation changes with the demand to withhold a response in general. Such results reveal age-related differences in prefrontal activation that are specific to stimulus valence and depend on the action required. PMID:22669035

  10. Deletion of glutamate delta-1 receptor in mouse leads to aberrant emotional and social behaviors.

    Roopali Yadav

    Full Text Available The delta family of ionotropic glutamate receptors consists of glutamate δ1 (GluD1 and glutamate δ2 (GluD2 receptors. While the role of GluD2 in the regulation of cerebellar physiology is well understood, the function of GluD1 in the central nervous system remains elusive. We demonstrate for the first time that deletion of GluD1 leads to abnormal emotional and social behaviors. We found that GluD1 knockout mice (GluD1 KO were hyperactive, manifested lower anxiety-like behavior, depression-like behavior in a forced swim test and robust aggression in the resident-intruder test. Chronic lithium rescued the depression-like behavior in GluD1 KO. GluD1 KO mice also manifested deficits in social interaction. In the sociability test, GluD1 KO mice spent more time interacting with an inanimate object compared to a conspecific mouse. D-Cycloserine (DCS administration was able to rescue social interaction deficits observed in GluD1 KO mice. At a molecular level synaptoneurosome preparations revealed lower GluA1 and GluA2 subunit expression in the prefrontal cortex and higher GluA1, GluK2 and PSD95 expression in the amygdala of GluD1 KO. Moreover, DCS normalized the lower GluA1 expression in prefrontal cortex of GluD1 KO. We propose that deletion of GluD1 leads to aberrant circuitry in prefrontal cortex and amygdala owing to its potential role in presynaptic differentiation and synapse formation. Furthermore, these findings are in agreement with the human genetic studies suggesting a strong association of GRID1 gene with several neuropsychiatric disorders including schizophrenia, bipolar disorder, autism spectrum disorders and major depressive disorder.

  11. Fusion of Saliency Maps for Visual Attention Selection in Dynamic Scenes

    Jiawei Xu

    2013-04-01

    Full Text Available Human vision system can optionally process the visual information and adjust the contradiction between the limited resources and the huge visual information. Building attention models similar to human visual attention system should be very beneficial to computer vision and machine intelligence; meanwhile, it has been a challenging task due to the complexity of human brain and limited understanding of the mechanisms underlying the human attention system. Previous studies emphasized on static attention, however the motion features, which are playing key roles in human attention system intuitively, have not been well integrated into the previous models. Motion features such as motion direction are assumed to be processed within the dorsal visual and the dorsal auditory pathways and there is no systematic approach to extract the motion cues well so far. In this paper, we proposed a generic Global Attention Model (GAM system based on visual attention analysis. The computational saliency map is superimposed by a set of saliency maps via different predefined approaches. We added three saliencies maps up together to reflect dominant motion features into the attention model, i.e., the fused saliency map at each frame is adjusted by the top-down, static and motion saliency maps. By doing this, the proposed attention model accommodating motion feature into the system so that it can responds to real visual events in a manner similar to the human visual attention system in a realistic circumstance. The visual challenges used in our experiments are selected from the benchmark video sequences. We tested the GAM on several dynamic scenes, such as traffic artery, parachuter landing and surfing, with high speed and cluttered background. The experiment results showed the GAM system demonstrated high robustness and real-time ability under complex dynamic scenes. Extensive evaluations based on comparisons with other approaches of the attention model results have

  12. Error awareness and salience processing in the oddball task: Shared neural mechanisms.

    Helga A Harsay

    2012-08-01

    Full Text Available A body of work suggests that there are similarities in the way we become aware of an error and process motivationally salient events. Yet, evidence for a shared neural mechanism has not been provided. A within-subject investigation of the brain regions involved in error awareness and salience processing has not been reported. While the neural response to motivationally salient events is classically studied during target detection after longer target-to-target intervals in an oddball task and engages a widespread insula-thalamo-cortical brain network, error awareness has recently been linked to, most prominently, anterior insula cortex. Here we explore whether the anterior insula activation for error awareness is related to salience processing, by testing for activation overlap in subjects undergoing two different task settings. Using a within-subjects design, we show activation overlap in six major brain areas during aware errors in an antisaccade task and during target detection (which were associated with longer target-to-target interval conditions in an oddball task: anterior insula, anterior cingulate, supplementary motor area, thalamus, brainstem and parietal lobe. Within subject analyses shows that the insula is engaged in both error awareness and the processing of salience, and that the anterior insula is more involved in both processes than the posterior insula. The results of a fine-grained spatial pattern overlap analysis between active clusters in the same subjects indicated that even if the anterior insula is activated for both error awareness and salience processing, the two types of processes might tend to activate non-identical neural ensembles on a finer-grained spatial level. Together, these outcomes suggest a similar functional phenomenon in the two different task settings. Error awareness and salience processing share a functional anatomy, with a tendency towards subregional dorsal and ventral specialization within the

  13. Modelling the formation of polycentric chromosome aberrations

    Sachs, R.K.; Tarver, J. (California Univ., Berkeley, CA (United States). Dept. of Mathematics); Yates, B.L.; Morgan, W.F. (California Univ., San Francisco, CA (United States))

    1992-10-01

    Exchange-type chromosome aberrations produced by ionizing radiation or restriction enzymes are believed to result from pairwise interaction of DNA double-strand breaks (dsb). In addition to dicentrics, such aberrations may include higher-order polycentries (tricentries, tetracentrics, etc.). The authors have developed computer programs that calculate the probability of the various polycentrics for a given average number of pairwise interactions. Two models are used. Model I incorporates kinetic competition between restitution, complete exchanges (illegitimate recombination events), and incomplete exchanges. Model II allows unrestituted breaks even if there is no recombination. The models were applied to experimental observations of aberrations produced in G[sub 1] Chinese hamster ovary cells after electroporation with the restriction enzyme PvuII, which produces blunt-end dsb. (author).

  14. Modelling the formation of polycentric chromosome aberrations

    Exchange-type chromosome aberrations produced by ionizing radiation or restriction enzymes are believed to result from pairwise interaction of DNA double-strand breaks (dsb). In addition to dicentrics, such aberrations may include higher-order polycentries (tricentries, tetracentrics, etc.). The authors have developed computer programs that calculate the probability of the various polycentrics for a given average number of pairwise interactions. Two models are used. Model I incorporates kinetic competition between restitution, complete exchanges (illegitimate recombination events), and incomplete exchanges. Model II allows unrestituted breaks even if there is no recombination. The models were applied to experimental observations of aberrations produced in G1 Chinese hamster ovary cells after electroporation with the restriction enzyme PvuII, which produces blunt-end dsb. (author)

  15. Chromosomal aberrations induced by alpha particles

    The chromosomal aberrations produced by the ionizing radiation are commonly used when it is necessary to establish the exposure dose of an individual, it is a study that is used like complement of the traditional physical systems and its application is only in cases in that there is doubt about what indicates the conventional dosimetry. The biological dosimetry is based on the frequency of aberrations in the chromosomes of the lymphocytes of the individual in study and the dose is calculated taking like reference to the dose-response curves previously generated In vitro. A case of apparent over-exposure to alpha particles to which is practiced analysis of chromosomal aberrations to settle down if in fact there was exposure and as much as possible, to determine the presumed dose is presented. (Author)

  16. Estimation of dose from chromosome aberration rate

    The methods and skills of evaluating dose from correctly scored shromsome aberration rate are presented, and supplemented with corresponding BASIC computer code. The possibility and preventive measures of excessive probability of missing score of the aberrations in some of the current routine score methods are discussed. The use of dose-effect relationship with exposure time correction factor G in evaluating doses and their confidence intervals, dose estimation in mixed n-γ exposure, and identification of high by nonuniform acute exposure to low LET radiation and its dose estimation are discussed in more detail. The difference of estimated dose due to whether the interaction between subleisoms produced by n and γ have been taken into account is examined. In fitting the standard dose-aberration rate curve, proper weighing of experiment points and comparison with commonly accepted values are emphasised, and the coefficient of variation σy√y of the aberration rate y as a function of dose and exposure time is given. In appendix I and II, the dose-aberration rate formula is derived from dual action theory, and the time variation of subleisom is illustrated and in appendix III, the estimation of dose from scores of two different types of aberrations (of other related score) is illustrated. Two computer codes are given in appendix IV, one is a simple code, the other a complete code, including the fitting of standard curve. the skills of using compressed data storage, and the production of simulated 'data ' for testing the curve fitting procedure are also given

  17. Altered functional connectivity of prefrontal cortex in chronic heroin abusers

    Yinbao Qi; Xianming Fu; Ruobing Qian; Chaoshi Niu; Xiangpin Wei

    2011-01-01

    In this study, we investigated alterations in the resting-state functional connectivity of the pre-frontal cortex in chronic heroin abusers using functional magnetic resonance imaging. We found that, compared with normal controls, in heroin abusers the left prefrontal cortex showed decreased functional connectivity with the left hippocampus, right anterior cingulate, left middle frontal gyrus, right middle frontal gyrus and right precuneus. However, the right prefrontal cortex showed decreased functional connectivity with the left orbital frontal cortex and the left middle frontal gyrus in chronic heroin abusers. These alterations of resting-state functional connectivity in the prefrontal cortices of heroin abusers suggest that their frontal executive neural network may be impaired, and that this may contribute to their continued heroin abuse and relapse after withdrawal.

  18. Coding of Vocalizations by Single Neurons in Ventrolateral Prefrontal Cortex

    Plakke, Bethany; Diltz, Mark D.; Romanski, Lizabeth M.

    2013-01-01

    Neuronal activity in single prefrontal neurons has been correlated with behavioral responses, rules, task variables and stimulus features. In the non-human primate, neurons recorded in ventrolateral prefrontal cortex (VLPFC) have been found to respond to species-specific vocalizations. Previous studies have found multisensory neurons which respond to simultaneously presented faces and vocalizations in this region. Behavioral data suggests that face and vocal information are inextricably linke...

  19. Prefrontal control of fear: more than just extinction

    Sotres-Bayon, Francisco; Quirk, Gregory J.

    2010-01-01

    While fear research has largely focused on the amygdala, recent findings highlight cortical control of the amygdala in the service of fear regulation. In rodent models, it is becoming well established that the infralimbic prefrontal cortex (IL) plays a key role in extinction learning, and recent findings are uncovering molecular mechanisms involved in extinction-related plasticity. Furthermore, mounting evidence implicates the prelimbic prefrontal cortex (PL) in the production of fear respons...

  20. The correction of electron lens aberrations

    Hawkes, P.W., E-mail: peter.hawkes@cemes.fr

    2015-09-15

    The progress of electron lens aberration correction from about 1990 onwards is chronicled. Reasonably complete lists of publications on this and related topics are appended. A present for Max Haider and Ondrej Krivanek in the year of their 65th birthdays. By a happy coincidence, this review was completed in the year that both Max Haider and Ondrej Krivanek reached the age of 65. It is a pleasure to dedicate it to the two leading actors in the saga of aberration corrector design and construction. They would both wish to associate their colleagues with such a tribute but it is the names of Haider and Krivanek (not forgetting Joachim Zach) that will remain in the annals of electron optics, next to that of Harald Rose. I am proud to know that both regard me as a friend as well as a colleague. - Highlights: • Geometrical aberration correction. • Chromatic aberration correction. • 50 pm resolution. • High-resolution electron energy-loss spectroscopy. • Extensive bibliographies.

  1. Aberration features in directional dark matter detection

    The motion of the Earth around the Sun causes an annual change in the magnitude and direction of the arrival velocity of dark matter particles on Earth, in a way analogous to aberration of stellar light. In directional detectors, aberration of weakly interacting massive particles (WIMPs) modulates the pattern of nuclear recoil directions in a way that depends on the orbital velocity of the Earth and the local galactic distribution of WIMP velocities. Knowing the former, WIMP aberration can give information on the latter, besides being a curious way of confirming the revolution of the Earth and the extraterrestrial provenance of WIMPs. While observing the full aberration pattern requires extremely large exposures, we claim that the annual variation of the mean recoil direction or of the event counts over specific solid angles may be detectable with moderately large exposures. For example, integrated counts over Galactic hemispheres separated by planes perpendicular to Earth's orbit would modulate annually, resulting in Galactic Hemisphere Annual Modulations (GHAM) with amplitudes larger than the usual non-directional annual modulation

  2. Prenatal hydronephrosis caused by aberrant renal vessels

    Lenz, K; Thorup, Jørgen Mogens; Rabol, A;

    1996-01-01

    With routine use of obstetric ultrasonography, fetal low-grade hydronephrosis is commonly detected, but may resolve spontaneously after birth. Two cases are presented to illustrate that in some cases such findings can express intermittent hydronephrosis caused by aberrant renal vessels. Renal det...

  3. The correction of electron lens aberrations

    The progress of electron lens aberration correction from about 1990 onwards is chronicled. Reasonably complete lists of publications on this and related topics are appended. A present for Max Haider and Ondrej Krivanek in the year of their 65th birthdays. By a happy coincidence, this review was completed in the year that both Max Haider and Ondrej Krivanek reached the age of 65. It is a pleasure to dedicate it to the two leading actors in the saga of aberration corrector design and construction. They would both wish to associate their colleagues with such a tribute but it is the names of Haider and Krivanek (not forgetting Joachim Zach) that will remain in the annals of electron optics, next to that of Harald Rose. I am proud to know that both regard me as a friend as well as a colleague. - Highlights: • Geometrical aberration correction. • Chromatic aberration correction. • 50 pm resolution. • High-resolution electron energy-loss spectroscopy. • Extensive bibliographies

  4. Optical advantages of astigmatic aberration corrected heliostats

    van Rooyen, De Wet; Schöttl, Peter; Bern, Gregor; Heimsath, Anna; Nitz, Peter

    2016-05-01

    Astigmatic aberration corrected heliostats adapt their shape in dependence of the incidence angle of the sun on the heliostat. Simulations show that this optical correction leads to a higher concentration ratio at the target and thus in a decrease in required receiver aperture in particular for smaller heliostat fields.

  5. Anti-forensics of chromatic aberration

    Mayer, Owen; Stamm, Matthew C.

    2015-03-01

    Over the past decade, a number of information forensic techniques have been developed to identify digital image manipulation and falsification. Recent research has shown, however, that an intelligent forger can use anti-forensic countermeasures to disguise their forgeries. In this paper, an anti-forensic technique is proposed to falsify the lateral chromatic aberration present in a digital image. Lateral chromatic aberration corresponds to the relative contraction or expansion between an image's color channels that occurs due to a lens's inability to focus all wavelengths of light on the same point. Previous work has used localized inconsistencies in an image's chromatic aberration to expose cut-and-paste image forgeries. The anti-forensic technique presented in this paper operates by estimating the expected lateral chromatic aberration at an image location, then removing deviations from this estimate caused by tampering or falsification. Experimental results are presented that demonstrate that our anti-forensic technique can be used to effectively disguise evidence of an image forgery.

  6. Cosmological parameter estimation: impact of CMB aberration

    The peculiar motion of an observer with respect to the CMB rest frame induces an apparent deflection of the observed CMB photons, i.e. aberration, and a shift in their frequency, i.e. Doppler effect. Both effects distort the temperature multipoles alm's via a mixing matrix at any l. The common lore when performing a CMB based cosmological parameter estimation is to consider that Doppler affects only the l = 1 multipole, and neglect any other corrections. In this paper we reconsider the validity of this assumption, showing that it is actually not robust when sky cuts are included to model CMB foreground contaminations. Assuming a simple fiducial cosmological model with five parameters, we simulated CMB temperature maps of the sky in a WMAP-like and in a Planck-like experiment and added aberration and Doppler effects to the maps. We then analyzed with a MCMC in a Bayesian framework the maps with and without aberration and Doppler effects in order to assess the ability of reconstructing the parameters of the fiducial model. We find that, depending on the specific realization of the simulated data, the parameters can be biased up to one standard deviation for WMAP and almost two standard deviations for Planck. Therefore we conclude that in general it is not a solid assumption to neglect aberration in a CMB based cosmological parameter estimation

  7. Visual saliency maps for studies of behavior of patients with neurodegenerative diseases: Observer's versus Actor's points of view

    Boujut, Hugo; Buso, Vincent; Benois-Pineau, Jenny; Gaëstel, Yann; Dartigues, Jean-François

    2013-01-01

    We are interested in finding the relation between the visual saliency maps of the viewer of visual content and the actors (person executing the actions) in the context of studies of neurodegenerative diseases such as Alzheimer's disease. From results of eye-trackers worn by the actors and used when recording observers, and on the basis of hand-eye interactions from motor control studies we established a time shift between actor's and viewer's saliency maps. This time shift corresponds to the ...

  8. Prefrontal dopamine in associative learning and memory.

    Puig, M V; Antzoulatos, E G; Miller, E K

    2014-12-12

    Learning to associate specific objects or actions with rewards and remembering the associations are everyday tasks crucial for our flexible adaptation to the environment. These higher-order cognitive processes depend on the prefrontal cortex (PFC) and frontostriatal circuits that connect areas in the frontal lobe with the striatum in the basal ganglia. Both structures are densely innervated by dopamine (DA) afferents that originate in the midbrain. Although the activity of DA neurons is thought to be important for learning, the exact role of DA transmission in frontostriatal circuits during learning-related tasks is still unresolved. Moreover, the neural substrates of this modulation are poorly understood. Here, we review our recent work in monkeys utilizing local pharmacology of DA agents in the PFC to investigate the cellular mechanisms of DA modulation of associative learning and memory. We show that blocking both D1 and D2 receptors in the lateral PFC impairs learning of new stimulus-response associations and cognitive flexibility, but not the memory of highly familiar associations. In addition, D2 receptors may also contribute to motivation. The learning deficits correlated with reductions of neural information about the associations in PFC neurons, alterations in global excitability and spike synchronization, and exaggerated alpha and beta neural oscillations. Our findings provide new insights into how DA transmission modulates associative learning and memory processes in frontostriatal systems. PMID:25241063

  9. Prefrontal control of attention to threat.

    Peers, Polly V; Simons, Jon S; Lawrence, Andrew D

    2013-01-01

    Attentional control refers to the regulatory processes that ensure that our actions are in accordance with our goals. Dual-system accounts view temperament as consisting of both individual variation in emotionality (e.g., trait anxiety) and variation in regulatory attentional mechanisms that act to modulate emotionality. Increasing evidence links trait variation in attentional control to clinical mood and anxiety disorder symptoms, independent of trait emotionality. Attentional biases to threat have been robustly linked to mood and anxiety disorders. However, the role of variation in attentional control in influencing such biases, and the neural underpinnings of trait variation in attentional control, are unknown. Here, we show that individual differences in trait attentional control, even when accounting for trait and state anxiety, are related to the magnitude of an attentional blink (AB) following threat-related targets. Moreover, we demonstrate that activity in dorso-lateral prefrontal cortex (DLPFC), is observed specifically in relation to control of attention over threatening stimuli, in line with neural theories of attentional control, such as guided activation theory. These results have key implications for neurocognitive theories of attentional bias and emotional resilience. PMID:23386824

  10. Prefrontal control of attention to threat

    Polly V Peers

    2013-02-01

    Full Text Available Attentional control refers to the regulatory processes that ensure that our actions are in accordance with our goals. Dual-system accounts view temperament as consisting of both individual variation in emotionality (e.g. trait anxiety and variation in regulatory attentional mechanisms that act to modulate emotionality. Increasing evidence links trait variation in attentional control to clinical mood and anxiety disorder symptoms, independent of trait emotionality. Attentional biases to threat have been robustly linked to mood and anxiety disorders. However, the role of variation in attentional control in influencing such biases, and the neural underpinnings of trait variation in attentional control, are unknown. Here, we show, that individual differences in trait attentional control, even when accounting for trait and state anxiety, are related to the magnitude of an attentional blink following threat-related targets. Moreover, we demonstrate that activity in dorsolateral prefrontal cortex, is observed specifically in relation to control of attention over threatening stimuli, in line with neural theories of attentional control, such as guided activation theory. These results have key implications for neurocognitive theories of attentional bias and emotional resilience.

  11. Multi-window visual saliency extraction for fusion of visible and infrared images

    Zhao, Jufeng; Gao, Xiumin; Chen, Yueting; Feng, Huajun; Wang, Daodang

    2016-05-01

    Fusion for visible and infrared images aims to combine the source images of the same scene into a single image with more feature information and better visual performance. In this paper, the authors propose a fusion method based on multi-window visual saliency extraction for visible and infrared images. To extract feature information from infrared and visible images, we design local-window-based frequency-tuned method. With this idea, visual saliency maps are calculated for variable feature information under different local window. These maps show the weights of people's attention upon images for each pixel and region. Enhanced fusion is done using simple weight combination way. Compared with the classical and state-of-the-art approaches, the experimental results demonstrate the proposed approach runs efficiently and performs better than other methods, especially in visual performance and details enhancement.

  12. Predicting Subjective Affective Salience from Cortical Responses to Invisible Object Stimuli.

    Schmack, Katharina; Burk, Julia; Haynes, John-Dylan; Sterzer, Philipp

    2016-08-01

    The affective value of a stimulus substantially influences its potency to gain access to awareness. Here, we sought to elucidate the neural mechanisms underlying such affective salience in a combined behavioral and fMRI experiment. Healthy individuals with varying degrees of spider phobia were presented with pictures of spiders and flowers suppressed from view by continuous flash suppression. Applying multivoxel pattern analysis, we found that the average time that spider stimuli took relative to flowers to gain access to awareness in each participant could be decoded from fMRI signals evoked by suppressed spider versus flower stimuli in occipitotemporal and orbitofrontal cortex. Our results indicate neural signals during unconscious processing of complex visual information in orbitofrontal and ventral visual areas predict access to awareness of this information, suggesting a crucial role for these higher-level cortical regions in mediating affective salience. PMID:26232987

  13. The interactive effects of mortality salience and political orientation on moral judgments.

    Bassett, Jonathan F; Van Tongeren, Daryl R; Green, Jeffrey D; Sonntag, Michael E; Kilpatrick, Harrison

    2015-06-01

    In two studies, the authors examined how threat induced by reminders of mortality would moderate the effect of political orientation on moral judgments. In Study 1, university students (n = 113) categorized their political orientation, were randomly assigned to complete a fear of death or public speaking scale, and then completed a moral foundations questionnaire. In Study 2, university students (n = 123) rated their political orientations, were randomly assigned to write about their own death or dental pain, and then completed a moral foundations questionnaire. In both studies, mortality salience intensified the moral differences between liberals and conservatives. These findings were primarily the result of the reactions of liberals, who responded to mortality salience with increased ratings of the fairness/cheating virtue in Study 1 and the care/harm virtue in Study 2. PMID:25302551

  14. Autonomy, Affiliation, and Ability: Relative Salience of Factors that Influence Online Learner Motivation and Learning Outcomes

    Kuan-Chung Chen

    2010-03-01

    Full Text Available Autonomy, affiliation, and ability appear as main factors that influence online learners‟ motivation and learning outcomes, however, the relative salience of these three factors remains unclear in the online learning literature. Drawing on Deci and Ryan‟s self-determination theory, this study sought to bridge this gap by investigating the relative salience of perceived autonomy, affiliation, and ability on learner motivation and learning outcomes in two special education online programs (N = 262. This study found that the most salient predictor varied from categories of motivation and learning outcomes, and the number of significant predictors increased by participants‟ level of motivation/self-determination. Results of this study provide implications for online learner support.

  15. Distinct Global Brain Dynamics and Spatiotemporal Organization of the Salience Network.

    Tianwen Chen; Weidong Cai; Srikanth Ryali; Kaustubh Supekar; Vinod Menon

    2016-01-01

    One of the most fundamental features of the human brain is its ability to detect and attend to salient goal-relevant events in a flexible manner. The salience network (SN), anchored in the anterior insula and the dorsal anterior cingulate cortex, plays a crucial role in this process through rapid detection of goal-relevant events and facilitation of access to appropriate cognitive resources. Here, we leverage the subsecond resolution of large multisession fMRI datasets from the Human Connecto...

  16. The undermining effect revisited: The salience of everyday verbal rewards and self-determined motivation

    Hewett, Rebecca; Conway, Neil

    2015-01-01

    Self-determination theory suggests that some rewards can undermine autonomous motivation and related positive outcomes. Key to this undermining is the extent to which rewards are perceived as salient in a given situation; when this is the case individuals tend to attribute their behavior to the incentive and the intrinsic value of the task is undermined. The role of salience has yet to be explicitly tested with respect to work motivation; we know little about whether undermining occurs in rel...

  17. Saliency Map for Visual Attention Region Prediction Based on Fuzzy Neural Network

    Wang, Mao; MAEDA, Yoichiro; Takahashi, Yasutake

    2014-01-01

    Visual attention region prediction has been paid much attention by researchers in intelligent systems recent years because it can make the interaction between human and intelligent agents to be more convenient. In this paper, the prediction method of the visual attention region inferred by using fuzzy neural network (FNN) after extracting and computing of images feature maps and saliency maps was proposed. A method for training FNN is also proposed. A user experiment was conducted to evaluate...

  18. Estimating the Relative Sociolinguistic Salience of Segmental Variables in a Dialect Boundary Zone

    Llamas, Carmen; Watt, Dominic; MacFarlane, Andrew E.

    2016-01-01

    One way of evaluating the salience of a linguistic feature is by assessing the extent to which listeners associate the feature with a social category such as a particular socioeconomic class, gender, or nationality. Such ‘top–down’ associations will inevitably differ somewhat from listener to listener, as a linguistic feature – the pronunciation of a vowel or consonant, for instance – can evoke multiple social category associations, depending upon the dialect in which the feature is embedded and the context in which it is heard. In a given speech community it is reasonable to expect, as a consequence of the salience of the linguistic form in question, a certain level of intersubjective agreement on social category associations. Two metrics we can use to quantify the salience of a linguistic feature are (a) the speed with which the association is made, and (b) the degree to which members of a speech community appear to share the association. Through the use of a new technique, designed as an adaptation of the Implicit Association Test, this paper examines levels of agreement among 40 informants from the Scottish/English border region with respect to the associations they make between four key phonetic variables and the social categories of ‘Scotland’ and ‘England.’ Our findings reveal that the participants exhibit differential agreement patterns across the set of phonetic variables, and that listeners’ responses vary in line with whether participants are members of the Scottish or the English listener groups. These results demonstrate the importance of community-level agreement with respect to the associations that listeners make between social categories and linguistic forms, and as a means of ranking the forms’ relative salience. PMID:27574511

  19. Distinct Global Brain Dynamics and Spatiotemporal Organization of the Salience Network

    Tianwen Chen; Weidong Cai; Srikanth Ryali; Kaustubh Supekar; Vinod Menon

    2016-01-01

    One of the most fundamental features of the human brain is its ability to detect and attend to salient goal-relevant events in a flexible manner. The salience network (SN), anchored in the anterior insula and the dorsal anterior cingulate cortex, plays a crucial role in this process through rapid detection of goal-relevant events and facilitation of access to appropriate cognitive resources. Here, we leverage the subsecond resolution of large multisession fMRI datasets from the Human Connecto...

  20. Perceptual salience of language-specific acoustic differences in autonomous fillers across eight languages

    Vasilescu, Ioana; Candea, Maria; Adda-Decker, Martine

    2005-01-01

    Are acoustic differences in autonomous fillers salient for the human perception ? Acoustic measurements have been carried out on autonomous fillers from eight languages (Arabic, Mandarin Chinese, French, German, Italian, European Portuguese, American English and Latin American Spanish). They exhibit timbre differences of the support vowel of autonomous fillers across languages. In order to evaluate their salience for human perception, two discrimination experiments have been conducted, French...

  1. Low-complexity motion-based saliency map estimation for perceptual video coding

    Mejía-Ocaña, Ana Belén; Frutos-López, Manuel de; Sanz-Rodríguez, Sergio; del-Ama-Esteban, Óscar; Peláez-Moreno, Carmen; Díaz-De-María, Fernando

    2011-01-01

    In this paper, a low-complexity motion-based saliency map estimation method for perceptual video coding is proposed. The method employs a camera motion compensated vector map computed by means of a hierarchical motion estimation (HME) procedure and a Restricted Affine Transformation (RAT)-based modeling of the camera motion. To allow for a computationally efficient solution, the number of layers of the HME has been restricted and the potential unreliable motion vectors due to homogeneous regi...

  2. Weighted-MSE based on Saliency map for assessing video quality of H.264 video streams

    Boujut, Hugo; Benois-Pineau, Jenny; Hadar, Ofer; Ahmed, Toufik; Bonnet, Patrick

    2011-01-01

    Human vision system is very complex and has been studied for many years specifically for purposes of efficient encoding of visual, e.g. video content from digital TV. There have been physiological and psychological evidences which indicate that viewers do not pay equal attention to all exposed visual information, but only focus on certain areas known as focus of attention (FOA) or saliency regions. In this work, we propose a novel based objective quality assessment metric, for assessing the p...

  3. Saliency map based attention control for the RoboCup SPL

    García Sierra, Juan Felipe; Rodríguez Lera, Francisco Javier; Fernández Llamas, Camino; Matellán Olivera, Vicente

    2010-01-01

    Attention mechanism can be used both for reducing the amount of perceptual information to be processed and for restricting all available actions to only those useful for a given scenario. Information reduction improves performance and action restriction allows for a more precise interaction with our environment. In this paper we present the design of an attention control mechanism based on a saliency map and its implementation in the SPL's Nao robot. The results obtained are analysed and fut...

  4. Salience network-midbrain dysconnectivity and blunted reward signals in schizophrenia

    Gradin, Victoria; Waiter, Gordon; O'Connor, Akira Robert; Romaniuk, Liana; Stickle, Catriona; Matthews, Keith; Hall, Jeremy; Steele, Douglas

    2012-01-01

    Theories of schizophrenia propose that abnormal functioning of the neural reward system is linked to negative and psychotic symptoms, by disruption of reward processing and promotion of context-independent false associations. Recently it has been argued that an insula-anterior cingulate cortex (ACC) salience network system enables switching of brain states from the default mode to a task-related activity mode. Abnormal interaction between the insula-ACC system and reward processing regions ma...

  5. Estimating the Relative Sociolinguistic Salience of Segmental Variables in a Dialect Boundary Zone.

    Llamas, Carmen; Watt, Dominic; MacFarlane, Andrew E

    2016-01-01

    One way of evaluating the salience of a linguistic feature is by assessing the extent to which listeners associate the feature with a social category such as a particular socioeconomic class, gender, or nationality. Such 'top-down' associations will inevitably differ somewhat from listener to listener, as a linguistic feature - the pronunciation of a vowel or consonant, for instance - can evoke multiple social category associations, depending upon the dialect in which the feature is embedded and the context in which it is heard. In a given speech community it is reasonable to expect, as a consequence of the salience of the linguistic form in question, a certain level of intersubjective agreement on social category associations. Two metrics we can use to quantify the salience of a linguistic feature are (a) the speed with which the association is made, and (b) the degree to which members of a speech community appear to share the association. Through the use of a new technique, designed as an adaptation of the Implicit Association Test, this paper examines levels of agreement among 40 informants from the Scottish/English border region with respect to the associations they make between four key phonetic variables and the social categories of 'Scotland' and 'England.' Our findings reveal that the participants exhibit differential agreement patterns across the set of phonetic variables, and that listeners' responses vary in line with whether participants are members of the Scottish or the English listener groups. These results demonstrate the importance of community-level agreement with respect to the associations that listeners make between social categories and linguistic forms, and as a means of ranking the forms' relative salience. PMID:27574511

  6. The relative salience of facial features when differentiating faces based on an interference paradigm

    Ruiz-Soler, Marcos; Salvador Beltrán, Francesc

    2012-01-01

    Research on face recognition and social judgment usually addresses the manipulation of facial features (eyes, nose, mouth, etc.). Using a procedure based on a Stroop-like task, Montepare and Opeyo (J Nonverbal Behav 26(1):43-59, 2002) established a hierarchy of the relative salience of cues based on facial attributes when differentiating faces. Using the same perceptual interference task, we established a hierarchy of facial features. Twenty-three participants (13 men and 10 women) volunteere...

  7. How saliency, faces, and sound influence gaze in dynamic social scenes.

    Coutrot, Antoine; Guyader, Nathalie

    2014-01-01

    Conversation scenes are a typical example in which classical models of visual attention dramatically fail to predict eye positions. Indeed, these models rarely consider faces as particular gaze attractors and never take into account the important auditory information that always accompanies dynamic social scenes. We recorded the eye movements of participants viewing dynamic conversations taking place in various contexts. Conversations were seen either with their original soundtracks or with unrelated soundtracks (unrelated speech and abrupt or continuous natural sounds). First, we analyze how auditory conditions influence the eye movement parameters of participants. Then, we model the probability distribution of eye positions across each video frame with a statistical method (Expectation-Maximization), allowing the relative contribution of different visual features such as static low-level visual saliency (based on luminance contrast), dynamic low level visual saliency (based on motion amplitude), faces, and center bias to be quantified. Through experimental and modeling results, we show that regardless of the auditory condition, participants look more at faces, and especially at talking faces. Hearing the original soundtrack makes participants follow the speech turn-taking more closely. However, we do not find any difference between the different types of unrelated soundtracks. These eyetracking results are confirmed by our model that shows that faces, and particularly talking faces, are the features that best explain the gazes recorded, especially in the original soundtrack condition. Low-level saliency is not a relevant feature to explain eye positions made on social scenes, even dynamic ones. Finally, we propose groundwork for an audiovisual saliency model. PMID:24993019

  8. The role of the collicular pathway in the salience-based progression of visual attention.

    Mizzi, Raphaël; Michael, George A

    2014-08-15

    Visual attention has been shown to progress from the most to the least salient item in a given scene. Cognitive and physiological models assume that this orienting of covert attention relies on the collicular pathway, involving the superior colliculus and the pulvinar. Recent studies questioned this statement as they described attentional capture by visual items invisible to the superior colliculus. Electrophysiological studies shown that there is no direct projections from short-wave receptors to the superior colliculus. S-cone stimuli can thus be employed to assess visual processing without the involvement of the collicular pathway. We have attempted to investigate whether this pathway is involved in the salience-based orientation of attention by presenting S-cone stimuli. Volunteers were asked to make a judgment regarding a target among two distractors (all items of unequal sizes). Items' location and size varied randomly, as well as color, randomly black or calibrated for each subject to activate exclusively S-cones. The hierarchical pattern testifying of the salience-based orientation of attention was only found with black stimuli, arguing in favor of an implication of the collicular pathway in salience. In a second experiment, one item was presented at a time in order to test the item-multiplicity effect by comparing experiments. Performance was the most penalized when presenting multiple stimuli in the black condition. Results were interpreted in terms of distinct modes of processing by the collicular and geniculate pathways. The establishment of salience that determines attentional progression appeared to be only possible when the collicular pathway was solicited. PMID:24880095

  9. Procedural justice and status : Status salience as antecedent of the fair process effect

    Prooijen, J.-W. van; Bos, K. van den; Wilke, H.A.M.

    2002-01-01

    The current article explores status as an antecedent of procedural fairness effects (the findings that perceived procedural fairness affects people’s reactions, e.g., their relational judgments). On the basis of the literature, the authors proposed that salience of the general concept of status leads people to be more attentive to procedural fairness information and that, as a consequence, stronger procedural fairness effects should be found. In correspondence with this hypothesis, Experiment...

  10. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience

    Diankun Gong; Hui He; Weiyi Ma; Dongbo Liu; Mengting Huang; Li Dong; Jinnan Gong; Jianfu Li; Cheng Luo; Dezhong Yao

    2016-01-01

    Action video games (AVGs) have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN) and Central Executive Network (CEN), which are responsible for attention and working memory, respectiv...

  11. Robust Single Trial Identification of Conscious Percepts Triggered by Sensory Events of Variable Saliency

    Marta Teixeira; Gabriel Pires; Miguel Raimundo; Sérgio Nascimento; Vasco Almeida; Miguel Castelo-Branco

    2014-01-01

    The neural correlates of visual awareness are elusive because of its fleeting nature. Here we have addressed this issue by using single trial statistical ‘‘brain reading’’ of neurophysiological event related (ERP) signatures of conscious perception of visual attributes with different levels of saliency. Behavioral reports were taken at every trial in 4 experiments addressing conscious access to color, luminance, and local phase offset cues. We found that single trial neurophysiologic...

  12. Salience Network and Olanzapine in Schizophrenia: Implications for Treatment in Anorexia Nervosa

    Stip, Emmanuel; Lungu, Ovidiu V

    2015-01-01

    The salience network (SN), a set of brain regions composed of the anterior fronto-insular cortex (aFI) and the anterior cingulate cortex (ACC), is usually involved in interoception, self-regulating, and action selection. Accumulating evidence indicates that dysfunctions in this network are associated with various pathophysiological deficits in both schizophrenia and eating disorders, stemming mainly from dysfunctional information processing of internal or external stimuli. In addition, the me...

  13. Learning-Based Visual Saliency Model for Detecting Diabetic Macular Edema in Retinal Image

    Xiaochun Zou; Xinbo Zhao; Yongjia Yang; Na Li

    2016-01-01

    This paper brings forth a learning-based visual saliency model method for detecting diagnostic diabetic macular edema (DME) regions of interest (RoIs) in retinal image. The method introduces the cognitive process of visual selection of relevant regions that arises during an ophthalmologist’s image examination. To record the process, we collected eye-tracking data of 10 ophthalmologists on 100 images and used this database as training and testing examples. Based on analysis, two properties (Fe...

  14. Change blindness in pigeons (Columba livia): the effects of change salience and timing

    Herbranson, Walter T

    2015-01-01

    Change blindness is a well-established phenomenon in humans, in which plainly visible changes in the environment go unnoticed. Recently a parallel change blindness phenomenon has been demonstrated in pigeons. The reported experiment follows up on this finding by investigating whether change salience affects change blindness in pigeons the same way it affects change blindness in humans. Birds viewed alternating displays of randomly generated lines back-projected onto three response keys, with ...

  15. Change Blindness in Pigeons (Columba livia): the Effects of Change Salience and Timing

    Walter Troy Herbranson

    2015-01-01

    Change blindness is a well-established phenomenon in humans, in which plainly visible changes in the environment go unnoticed. Recently a parallel change blindness phenomenon has been demonstrated in pigeons. The reported experiment follows up on this finding by investigating whether change salience affects change blindness in pigeons the same way it affects change blindness in humans. Birds viewed alternating displays of randomly generated lines back-projected onto three response keys, wi...

  16. Adaptive and aberrant reward prediction signals in the human brain.

    Roiser, J.P.; Stephan, K.E.; Ouden, H.E.M. den; Friston, K.J.; Joyce, E.M.

    2010-01-01

    Theories of the positive symptoms of schizophrenia hypothesize a role for aberrant reinforcement signaling driven by dysregulated dopamine transmission. Recently, we provided evidence of aberrant reward learning in symptomatic, but not asymptomatic patients with schizophrenia, using a novel paradigm

  17. Using Saliency-Weighted Disparity Statistics for Objective Visual Comfort Assessment of Stereoscopic Images

    Zhang, Wenlan; Luo, Ting; Jiang, Gangyi; Jiang, Qiuping; Ying, Hongwei; Lu, Jing

    2016-06-01

    Visual comfort assessment (VCA) for stereoscopic images is a particularly significant yet challenging task in 3D quality of experience research field. Although the subjective assessment given by human observers is known as the most reliable way to evaluate the experienced visual discomfort, it is time-consuming and non-systematic. Therefore, it is of great importance to develop objective VCA approaches that can faithfully predict the degree of visual discomfort as human beings do. In this paper, a novel two-stage objective VCA framework is proposed. The main contribution of this study is that the important visual attention mechanism of human visual system is incorporated for visual comfort-aware feature extraction. Specifically, in the first stage, we first construct an adaptive 3D visual saliency detection model to derive saliency map of a stereoscopic image, and then a set of saliency-weighted disparity statistics are computed and combined to form a single feature vector to represent a stereoscopic image in terms of visual comfort. In the second stage, a high dimensional feature vector is fused into a single visual comfort score by performing random forest algorithm. Experimental results on two benchmark databases confirm the superior performance of the proposed approach.

  18. Hopelessly mortal: The role of mortality salience, immortality and trait self-esteem in personal hope.

    Wisman, Arnaud; Heflick, Nathan A

    2016-08-01

    Do people lose hope when thinking about death? Based on Terror Management Theory, we predicted that thoughts of death (i.e., mortality salience) would reduce personal hope for people low, but not high, in self-esteem, and that this reduction in hope would be ameliorated by promises of immortality. In Studies 1 and 2, mortality salience reduced personal hope for people low in self-esteem, but not for people high in self-esteem. In Study 3, mortality salience reduced hope for people low in self-esteem when they read an argument that there is no afterlife, but not when they read "evidence" supporting life after death. In Study 4, this effect was replicated with an essay affirming scientific medical advances that promise immortality. Together, these findings uniquely demonstrate that thoughts of mortality interact with trait self-esteem to cause changes in personal hope, and that literal immortality beliefs can aid psychological adjustment when thinking about death. Implications for understanding personal hope, trait self-esteem, afterlife beliefs and terror management are discussed. PMID:25920481

  19. The dimensional salience solution to the expectancy-value muddle: an extension.

    Newton, Joshua D; Newton, Fiona J; Ewing, Michael T

    2014-01-01

    The theory of reasoned action (TRA) specifies a set of expectancy-value, belief-based frameworks that underpin attitude (behavioural beliefs × outcome evaluations) and subjective norm (normative beliefs × motivation to comply). Unfortunately, the most common method for analysing these frameworks generates statistically uninterpretable findings, resulting in what has been termed the 'expectancy-value muddle'. Recently, however, a dimensional salience approach was found to resolve this muddle for the belief-based framework underpinning attitude. An online survey of 262 participants was therefore conducted to determine whether the dimensional salience approach could also be applied to the belief-based framework underpinning subjective norm. Results revealed that motivations to comply were greater for salient, as opposed to non-salient, social referents. The belief-based framework underpinning subjective norm was therefore represented by evaluating normative belief ratings for salient social referents. This modified framework was found to predict subjective norm, although predictions were greater when participants were forced to select five salient social referents rather than being free to select any number of social referents. These findings validate the use of the dimensional salience approach for examining the belief-based frameworks underpinning subjective norm. As such, this approach provides a complete solution to addressing the expectancy-value muddle in the TRA. PMID:25088611

  20. Mortality Salience, System Justification, and Candidate Evaluations in the 2012 U.S. Presidential Election

    Sterling, Joanna; Jost, John T.; Shrout, Patrick E.

    2016-01-01

    Experiments conducted during the 2004 and 2008 U.S. presidential elections suggested that mortality salience primes increased support for President George W. Bush and Senator John McCain, respectively. Some interpreted these results as reflecting “conservative shift” following exposure to threat, whereas others emphasized preferences for “charismatic” leadership following exposure to death primes. To assess both hypotheses in the context of a new election cycle featuring a liberal incumbent who was considered to be charismatic, we conducted four experiments shortly before the 2012 election involving President Barack Obama and Governor Mitt Romney. Contrary to earlier studies, there was little evidence that mortality salience, either by itself or in interaction with political orientation, affected overall candidate ratings or voting intentions. However, a significant interaction between mortality salience and system justification in some studies indicated a more circumscribed effect. The failure to “replicate” previous results in the context of this election may be attributable to disagreement among participants as to which of the candidates better represented the societal status quo. PMID:26982197

  1. Top-Down Visual Saliency Detection in Optical Satellite Images Based on Local Adaptive Regression Kernel

    Xiaoguang Cui

    2014-01-01

    Full Text Available This paper proposes a novel top-down visual saliency detection method for optical satellite images using local adaptive regression kernels. This method provides a saliency map by measuring the likeness of image patches to a given single template image. The local adaptive regression kernel (LARK is used as a descriptor to extract feature and compare against analogous feature from the target image. A multi-scale pyramid of the target image is constructed to cope with large-scale variations. In addition, accounting for rotation variations, the histogram of kernel orientation is employed to estimate the rotation angle of image patch, and then comparison is performed after rotating the patch by the estimated angle. Moreover, we use the bounded partial correlation (BPC to compare features between image patches and the template so as to rapidly generate the saliency map. Experiments were performed in optical satellite images to find airplanes, and experimental results demonstrate that the proposed method is effective and robust in complex scenes.

  2. Mortality Salience, System Justification, and Candidate Evaluations in the 2012 U.S. Presidential Election.

    Sterling, Joanna; Jost, John T; Shrout, Patrick E

    2016-01-01

    Experiments conducted during the 2004 and 2008 U.S. presidential elections suggested that mortality salience primes increased support for President George W. Bush and Senator John McCain, respectively. Some interpreted these results as reflecting "conservative shift" following exposure to threat, whereas others emphasized preferences for "charismatic" leadership following exposure to death primes. To assess both hypotheses in the context of a new election cycle featuring a liberal incumbent who was considered to be charismatic, we conducted four experiments shortly before the 2012 election involving President Barack Obama and Governor Mitt Romney. Contrary to earlier studies, there was little evidence that mortality salience, either by itself or in interaction with political orientation, affected overall candidate ratings or voting intentions. However, a significant interaction between mortality salience and system justification in some studies indicated a more circumscribed effect. The failure to "replicate" previous results in the context of this election may be attributable to disagreement among participants as to which of the candidates better represented the societal status quo. PMID:26982197

  3. Mortality Salience, System Justification, and Candidate Evaluations in the 2012 U.S. Presidential Election.

    Joanna Sterling

    Full Text Available Experiments conducted during the 2004 and 2008 U.S. presidential elections suggested that mortality salience primes increased support for President George W. Bush and Senator John McCain, respectively. Some interpreted these results as reflecting "conservative shift" following exposure to threat, whereas others emphasized preferences for "charismatic" leadership following exposure to death primes. To assess both hypotheses in the context of a new election cycle featuring a liberal incumbent who was considered to be charismatic, we conducted four experiments shortly before the 2012 election involving President Barack Obama and Governor Mitt Romney. Contrary to earlier studies, there was little evidence that mortality salience, either by itself or in interaction with political orientation, affected overall candidate ratings or voting intentions. However, a significant interaction between mortality salience and system justification in some studies indicated a more circumscribed effect. The failure to "replicate" previous results in the context of this election may be attributable to disagreement among participants as to which of the candidates better represented the societal status quo.

  4. Individual variation in the propensity to attribute incentive salience to a food cue: influence of sex

    Pitchers, Kyle K.; Flagel, Shelly B.; O’Donnell, Elizabeth G.; Solberg Woods, Leah C.; Sarter, M.; Robinson, Terry E.

    2014-01-01

    There is considerable individual variation in the propensity of animals to attribute incentive salience to discrete reward cues, but to date most of this research has been conducted in male rats. The purpose of this study was to determine whether sex influences the propensity to attribute incentive salience to a food cue, using rats from two different outbred strains (Sprague-Dawley [SD] and Heterogeneous Stock [HS]). The motivational value of a food cue was assessed in two ways: (i) by the ability of the cue to elicit approach towards it and (ii) by its ability to act as a conditioned reinforcer. We found that female SD rats acquired Pavlovian conditioned approach behavior slightly faster than males, but no sex difference was detected in HS rats, and neither strain showed a sex difference in asymptotic performance of approach behavior. Moreover, female approach behavior did not differ across estrous cycle. Compared to males, females made more active responses during the test for conditioned reinforcement, although they made more inactive responses as well. We conclude that although there are small sex differences in performance on these tasks, these are probably not due to a notable sex difference in the propensity to attribute incentive salience to a food cue. PMID:25446811

  5. Multi-trait mimicry and the relative salience of individual traits.

    Kazemi, Baharan; Gamberale-Stille, Gabriella; Leimar, Olof

    2015-11-01

    Mimicry occurs when one species gains protection from predators by resembling an unprofitable model species. The degree of mimic-model similarity is variable in nature and is closely related to the number of traits that the mimic shares with its model. Here, we experimentally test the hypothesis that the relative salience of traits, as perceived by a predator, is an important determinant of the degree of mimic-model similarity required for successful mimicry. We manipulated the relative salience of the traits of a two-trait artificial model prey, and subsequently tested the survival of mimics of the different traits. The unrewarded model prey had two colour traits, black and blue, and the rewarded prey had two combinations of green, brown and grey shades. Blue tits were used as predators. We found that the birds perceived the black and blue traits to be similarly salient in one treatment, and mimic-model similarity in both traits was then required for high mimic success. In a second treatment, the blue trait was the most salient trait, and mimic-model similarity in this trait alone achieved high success. Our results thus support the idea that similar salience of model traits can explain the occurrence of multi-trait mimicry. PMID:26511051

  6. Prefrontal cortex and social cognition in mouse and man

    Lucy King Bicks; Hiroyuki eKoike; Schahram eAkbarian; Hirofumi eMorishita

    2015-01-01

    Social cognition is a complex process that requires the integration of a wide variety of behaviors, including salience, reward-seeking, motivation, knowledge of self and others, and flexibly adjusting behavior in social groups. Not surprisingly, social cognition represents a sensitive domain commonly disrupted in the pathology of a variety of psychiatric disorders including Autism Spectrum Disorder (ASD) and Schizophrenia (SCZ). Here, we discuss convergent research from animal models to human...

  7. Prefrontal Cortex and Social Cognition in Mouse and Man

    Bicks, Lucy K.; Koike, Hiroyuki; Akbarian, Schahram; Morishita, Hirofumi

    2015-01-01

    Social cognition is a complex process that requires the integration of a wide variety of behaviors, including salience, reward-seeking, motivation, knowledge of self and others, and flexibly adjusting behavior in social groups. Not surprisingly, social cognition represents a sensitive domain commonly disrupted in the pathology of a variety of psychiatric disorders including Autism Spectrum Disorder (ASD) and Schizophrenia (SCZ). Here, we discuss convergent research from animal models to human...

  8. Primary aberrations in focused radially polarized vortex beams

    Biss, David P.; Brown, T. G.

    2004-02-01

    We study the effect of primary aberrations on the 3-D polarization of the electric field in a focused lowest order radially polarized beam. A full vector diffraction treatment of the focused beams is used. Attention is given to the effects of primary spherical, astigmatic, and comatic aberrations on the local polarization, Strehl ratio, and aberration induced degradation of the longitudinal field at focus

  9. Prefrontal neuronal assemblies temporally control fear behaviour.

    Dejean, Cyril; Courtin, Julien; Karalis, Nikolaos; Chaudun, Fabrice; Wurtz, Hélène; Bienvenu, Thomas C M; Herry, Cyril

    2016-07-21

    Precise spike timing through the coordination and synchronization of neuronal assemblies is an efficient and flexible coding mechanism for sensory and cognitive processing. In cortical and subcortical areas, the formation of cell assemblies critically depends on neuronal oscillations, which can precisely control the timing of spiking activity. Whereas this form of coding has been described for sensory processing and spatial learning, its role in encoding emotional behaviour remains unknown. Fear behaviour relies on the activation of distributed structures, among which the dorsal medial prefrontal cortex (dmPFC) is known to be critical for fear memory expression. In the dmPFC, the phasic activation of neurons to threat-predicting cues, a spike-rate coding mechanism, correlates with conditioned fear responses and supports the discrimination between aversive and neutral stimuli. However, this mechanism does not account for freezing observed outside stimuli presentations, and the contribution of a general spike-time coding mechanism for freezing in the dmPFC remains to be established. Here we use a combination of single-unit and local field potential recordings along with optogenetic manipulations to show that, in the dmPFC, expression of conditioned fear is causally related to the organization of neurons into functional assemblies. During fear behaviour, the development of 4 Hz oscillations coincides with the activation of assemblies nested in the ascending phase of the oscillation. The selective optogenetic inhibition of dmPFC neurons during the ascending or descending phases of this oscillation blocks and promotes conditioned fear responses, respectively. These results identify a novel phase-specific coding mechanism, which dynamically regulates the development of dmPFC assemblies to control the precise timing of fear responses. PMID:27409809

  10. Salience in Second Language Acquisition: Physical Form, Learner Attention, and Instructional Focus

    Cintrón-Valentín, Myrna C.; Ellis, Nick C.

    2016-01-01

    We consider the role of physical form, prior experience, and form focused instruction (FFI) in adult language learning. (1) When presented with competing cues to interpretation, learners are more likely to attend to physically more salient cues in the input. (2) Learned attention is an associative learning phenomenon where prior-learned cues block those that are experienced later. (3) The low salience of morphosyntactic cues can be overcome by FFI, which leads learners to attend cues which might otherwise be ignored. Experiment 1 used eye-tracking to investigate how language background influences learners’ attention to morphological cues, as well as the attentional processes whereby different types of FFI overcome low cue salience, learned attention and blocking. Chinese native speakers (no L1 verb-tense morphology) viewed Latin utterances combining lexical and morphological cues to temporality under control conditions (CCs) and three types of explicit FFI: verb grammar instruction (VG), verb salience with textual enhancement (VS), and verb pretraining (VP), and their use of these cues was assessed in a subsequent comprehension test. CC participants were significantly more sensitive to the adverbs than verb morphology. Instructed participants showed greater sensitivity to the verbs. These results reveal attentional processes whereby learners’ prior linguistic experience can shape their attention toward cues in the input, and whereby FFI helps learners overcome the long-term blocking of verb-tense morphology. Experiment 2 examined the role of modality of input presentation – aural or visual – in L1 English learners’ attentional focus on morphological cues and the effectiveness of different FFI manipulations. CC participants showed greater sensitivity toward the adverb cue. FFI was effective in increasing attention to verb-tense morphology, however, the processing of morphological cues was considerably more difficult under aural presentation. From visual

  11. Salience in Second Language Acquisition: Physical Form, Learner Attention, and Instructional Focus.

    Cintrón-Valentín, Myrna C; Ellis, Nick C

    2016-01-01

    We consider the role of physical form, prior experience, and form focused instruction (FFI) in adult language learning. (1) When presented with competing cues to interpretation, learners are more likely to attend to physically more salient cues in the input. (2) Learned attention is an associative learning phenomenon where prior-learned cues block those that are experienced later. (3) The low salience of morphosyntactic cues can be overcome by FFI, which leads learners to attend cues which might otherwise be ignored. Experiment 1 used eye-tracking to investigate how language background influences learners' attention to morphological cues, as well as the attentional processes whereby different types of FFI overcome low cue salience, learned attention and blocking. Chinese native speakers (no L1 verb-tense morphology) viewed Latin utterances combining lexical and morphological cues to temporality under control conditions (CCs) and three types of explicit FFI: verb grammar instruction (VG), verb salience with textual enhancement (VS), and verb pretraining (VP), and their use of these cues was assessed in a subsequent comprehension test. CC participants were significantly more sensitive to the adverbs than verb morphology. Instructed participants showed greater sensitivity to the verbs. These results reveal attentional processes whereby learners' prior linguistic experience can shape their attention toward cues in the input, and whereby FFI helps learners overcome the long-term blocking of verb-tense morphology. Experiment 2 examined the role of modality of input presentation - aural or visual - in L1 English learners' attentional focus on morphological cues and the effectiveness of different FFI manipulations. CC participants showed greater sensitivity toward the adverb cue. FFI was effective in increasing attention to verb-tense morphology, however, the processing of morphological cues was considerably more difficult under aural presentation. From visual exposure

  12. 4-Hz oscillations synchronize prefrontal-amygdala circuits during fear behavior.

    Karalis, Nikolaos; Dejean, Cyril; Chaudun, Fabrice; Khoder, Suzana; Rozeske, Robert R; Wurtz, Hélène; Bagur, Sophie; Benchenane, Karim; Sirota, Anton; Courtin, Julien; Herry, Cyril

    2016-04-01

    Fear expression relies on the coordinated activity of prefrontal and amygdala circuits, yet the mechanisms allowing long-range network synchronization during fear remain unknown. Using a combination of extracellular recordings, pharmacological and optogenetic manipulations, we found that freezing, a behavioral expression of fear, temporally coincided with the development of sustained, internally generated 4-Hz oscillations in prefrontal-amygdala circuits. 4-Hz oscillations predict freezing onset and offset and synchronize prefrontal-amygdala circuits. Optogenetic induction of prefrontal 4-Hz oscillations coordinates prefrontal-amygdala activity and elicits fear behavior. These results unravel a sustained oscillatory mechanism mediating prefrontal-amygdala coupling during fear behavior. PMID:26878674

  13. The correction of electron lens aberrations.

    Hawkes, P W

    2015-09-01

    The progress of electron lens aberration correction from about 1990 onwards is chronicled. Reasonably complete lists of publications on this and related topics are appended. A present for Max Haider and Ondrej Krivanek in the year of their 65th birthdays. By a happy coincidence, this review was completed in the year that both Max Haider and Ondrej Krivanek reached the age of 65. It is a pleasure to dedicate it to the two leading actors in the saga of aberration corrector design and construction. They would both wish to associate their colleagues with such a tribute but it is the names of Haider and Krivanek (not forgetting Joachim Zach) that will remain in the annals of electron optics, next to that of Harald Rose. I am proud to know that both regard me as a friend as well as a colleague. PMID:26025209

  14. Tailored displays to compensate for visual aberrations

    Pamplona, Vitor F.; Oliveira, Manuel M.; Aliaga, Daniel G.; Raskar, Ramesh

    2012-01-01

    We introduce tailored displays that enhance visual acuity by decomposing virtual objects and placing the resulting anisotropic pieces into the subject's focal range. The goal is to free the viewer from needing wearable optical corrections when looking at displays. Our tailoring process uses aberration and scattering maps to account for refractive errors and cataracts. It splits an object's light field into multiple instances that are each in-focus for a given eye sub-aperture. Their integrati...

  15. Prefrontal cortical microcircuits bind perception to executive control

    Opris, Ioan; Santos, Lucas; Gerhardt, Greg A.; Song, Dong; Berger, Theodore W.; Hampson, Robert E.; Deadwyler, Sam A.

    2013-07-01

    During the perception-to-action cycle, our cerebral cortex mediates the interactions between the environment and the perceptual-executive systems of the brain. At the top of the executive hierarchy, prefrontal cortical microcircuits are assumed to bind perceptual and executive control information to guide goal-driven behavior. Here, we tested this hypothesis by comparing simultaneously recorded neuron firing in prefrontal cortical layers and the caudate-putamen of rhesus monkeys, trained in a spatial-versus-object, rule-based match-to-sample task. We found that during the perception and executive selection phases, cell firing in the localized prefrontal layers and caudate-putamen region exhibited similar location preferences on spatial-trials, but less on object- trials. Then, we facilitated the perceptual-executive circuit by stimulating the prefrontal infra-granular-layers with patterns previously derived from supra-granular-layers, and produced stimulation-induced spatial preference in percent correct performance on spatial trials, similar to neural tuning. These results show that inter-laminar prefrontal microcircuits play causal roles to the perception-to-action cycle.

  16. DISC1 Ser704Cys impacts thalamic-prefrontal connectivity.

    Liu, Bing; Fan, Lingzhong; Cui, Yue; Zhang, Xiaolong; Hou, Bing; Li, Yonghui; Qin, Wen; Wang, Dawei; Yu, Chunshui; Jiang, Tianzi

    2015-01-01

    The Disrupted-in-Schizophrenia 1 (DISC1) gene has been thought as a putative susceptibility gene for various psychiatric disorders, and DISC1 Ser704Cys is associated with variations of brain morphology and function. Moreover, our recent diffusion magnetic resonance imaging (dMRI) study reported that DISC1 Ser704Cys was associated with information transfer efficiency in the brain anatomical network. However, the effects of the DISC1 gene on functional brain connectivity and networks, especially for thalamic-prefrontal circuit, which are disrupted in various psychiatric disorders, are largely unknown. Using a functional connectivity density (FCD) mapping method based on functional magnetic resonance imaging data in a large sample of healthy Han Chinese subjects, we first investigated the association between DISC1 Ser704Cys and short- and long-range FCD hubs. Compared with Ser homozygotes, Cys-allele individuals had increased long-range FCD hubs in the bilateral thalami. The functional and anatomical connectivity of the thalamus to the prefrontal cortex was further analyzed. Significantly increased thalamic-prefrontal functional connectivity and decreased thalamic-prefrontal anatomical connectivity were found in DISC1 Cys-allele carriers. Our findings provide consistent evidence that the DISC1 Ser704Cys polymorphism influences the thalamic-prefrontal circuits in humans and may provide new insights into the neural mechanisms that link DISC1 and the risk for psychiatric disorders. PMID:24146131

  17. DNA Repair Defects and Chromosomal Aberrations

    Hada, Megumi; George, K. A.; Huff, J. L.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

  18. Radiotherapeutical chromosomal aberrations in laryngeal cancer patients

    Stošić-Divjak Svetlana L.

    2009-01-01

    Full Text Available Introduction. The authors present the results of cytogenetic analysis of 21 patients with laryngeal carcinomas diagnosed and treated in the period 1995-2000 at the Institute of Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia and Clinical Center of Novi Sad. Material and methods. The patients were specially monitored and the material was analyzed at the Institute of Human Genetics of the School of Medicine in Belgrade as well as in the Laboratory for Radiological Protection of the Institute of Occupational and Radiological Health 'Dr Dragomir Karajovic' in Belgrade. Results. The incidence of chromosomal aberrations and incidence of exchange of material between sister chromatids were observed in the preparation of the metaphasic lymphocyte chromosomes of the peripheral blood obtained in the culture. Structural aberrations were found on the chromosomes in the form of breakups, rings, translocations and dicentrics as early as after a single exposure of patients to tumor radiation dose of 2 Gy in the field sized 5x7. Out of the total number of 35 cultivated blood samples obtained from 13 patients, 21 were successfully cultivated and they were proved to contain chromosomal aberrations. Some of the peripheral blood samples failed to show cell growth in vitro due to the lethal cell damages in vivo. Discussion.. We have consluded that the number of structural aberrations cannot be used as a biological measure of the absorbed ionizing radiation dose. The presence of aberrations per se is indicative of the mutagenic effect of the ionizing radiation, which was also confirmed in our series on the original model by cultivation of the peripheral blood lymphocytes in the culture of the cells of the volunteer donors upon in vitro radiation. Using the method of bromdeoxyuridylreductase, the increased incidence of SCE as a mutagenic effect was registered. Conclusion. It has been concluded that the increase of absorbed radiation dose in

  19. Chromatic variation of aberration: the role of induced aberrations and raytrace direction

    Berner, A.; Nobis, T.; Shafer, D.; Gross, H.

    2015-09-01

    The design and optimization process of an optical system contains several first order steps. The definition of the appropriate lens type and the fixation of the raytrace direction are some of them. The latter can be understood as a hidden assumption rather than an aware design step. This is usually followed by the determination of the paraxial lens layout calculated for the primary wavelength. It is obvious, that for this primary wavelength the paraxial calculations are independent of raytrace direction. Today, most of the lens designs are specified not to work only for one wavelength, but in a certain wavelength range. Considering such rays of other wavelengths, one can observe that depending on the direction there will already occur differences in the first order chromatic aberrations and additionally in the chromatic variation of the third-order aberrations. The reason for this effect are induced aberrations emerging from one surface to the following surfaces by perturbed ray heights and ray angles. It can be shown, that the total amount of surface-resolved first order chromatic aberrations and the chromatic variation of the five primary aberrations can be split into an intrinsic part and an induced part. The intrinsic part is independent of the raytrace direction whereas the induced part is not.

  20. Speed-accuracy strategy regulations in prefrontal tumor patients.

    Campanella, Fabio; Skrap, Miran; Vallesi, Antonino

    2016-02-01

    The ability to flexibly switch between fast and accurate decisions is crucial in everyday life. Recent neuroimaging evidence suggested that left lateral prefrontal cortex plays a role in switching from a quick response strategy to an accurate one. However, the causal role of the left prefrontal cortex in this particular, non-verbal, strategy switch has never been demonstrated. To fill this gap, we administered a perceptual decision-making task to neuro-oncological prefrontal patients, in which the requirement to be quick or accurate changed randomly on a trial-by-trial basis. To directly assess hemispheric asymmetries in speed-accuracy regulation, patients were tested a few days before and a few days after surgical excision of a brain tumor involving either the left (N=13) or the right (N=12) lateral frontal brain region. A group of age- and education-matched healthy controls was also recruited. To gain more insight on the component processes implied in the task, performance data (accuracy and speed) were not only analyzed separately but also submitted to a diffusion model analysis. The main findings indicated that the left prefrontal patients were impaired in appropriately adopting stricter response criteria in speed-to-accuracy switching trials with respect to healthy controls and right prefrontal patients, who were not impaired in this condition. This study demonstrates that the prefrontal cortex in the left hemisphere is necessary for flexible behavioral regulations, in particular when setting stricter response criteria is required in order to successfully switch from a speedy strategy to an accurate one. PMID:26772144

  1. Benchmark three-dimensional eye-tracking dataset for visual saliency prediction on stereoscopic three-dimensional video

    Banitalebi-Dehkordi, Amin; Nasiopoulos, Eleni; Pourazad, Mahsa T.; Nasiopoulos, Panos

    2016-01-01

    Visual attention models (VAMs) predict the location of image or video regions that are most likely to attract human attention. Although saliency detection is well explored for two-dimensional (2-D) image and video content, there have been only a few attempts made to design three-dimensional (3-D) saliency prediction models. Newly proposed 3-D VAMs have to be validated over large-scale video saliency prediction datasets, which also contain results of eye-tracking information. There are several publicly available eye-tracking datasets for 2-D image and video content. In the case of 3-D, however, there is still a need for large-scale video saliency datasets for the research community for validating different 3-D VAMs. We introduce a large-scale dataset containing eye-tracking data collected from 61 stereoscopic 3-D videos (and also 2-D versions of those), and 24 subjects participated in a free-viewing test. We evaluate the performance of the existing saliency detection methods over the proposed dataset. In addition, we created an online benchmark for validating the performance of the existing 2-D and 3-D VAMs and facilitating the addition of new VAMs to the benchmark. Our benchmark currently contains 50 different VAMs.

  2. Individual variation in the propensity to attribute incentive salience to an appetitive cue predicts the propensity to attribute motivational salience to an aversive cue.

    Morrow, Jonathan D; Maren, Stephen; Robinson, Terry E

    2011-06-20

    It has been proposed that animals that attribute high levels of incentive salience to reward-related cues may be especially vulnerable to addiction. Individual variation has also been observed in the motivational value attributed to aversive cues, which may confer vulnerability to anxiety disorders such as post-traumatic stress disorder (PTSD). There may be a core behavioral trait that contributes to individual variation in the motivational value assigned to predictive cues regardless of emotional valence. To test this hypothesis, we used a Pavlovian conditioned approach procedure to classify rats based on whether they learned to approach and interact with a cue predicting food reward (sign-trackers) or learned upon cue presentation to go to the location of impending food delivery (goal-trackers), and then examined Pavlovian fear conditioning in the same animals. It has recently been proposed that sign-trackers are more vulnerable to substance abuse because they attribute greater incentive motivational value to drug cues. Here we show that sign-trackers also have a tendency to be more fearful of discrete cues that predict footshock. In addition, we found that goal-trackers exhibited greater contextual fear when placed back into the original fear-conditioning context in the absence of temporally discrete cues. These results suggest that there may be a subset of individuals who tend to attribute high levels of motivational salience to predictive cues regardless of emotional valence, which may predispose them to a number of psychiatric comorbidities including PTSD and substance abuse. Other individuals use contexts to appropriately modify their reactions to such salient stimuli. PMID:21316397

  3. Chromosomal aberrations in ISS crew members

    Johannes, Christian; Goedecke, Wolfgang; Antonopoulos, Alexandra

    2012-07-01

    High energy radiation is a major risk factor in manned space missions. Astronauts and cosmonauts are exposed to ionising radiations of cosmic and solar origin, while on the Earth's surface people are well protected by the atmosphere and a deflecting magnetic field. There are now data available describing the dose and the quality of ionising radiation on-board of the International Space Station (ISS). Nonetheless, the effect of increased radiation dose on mutation rates of ISS crew members are hard to predict. Therefore, direct measurements of mutation rates are required in order to better estimate the radiation risk for longer duration missions. The analysis of chromosomal aberrations in peripheral blood lymphocytes is a well established method to measure radiation-induced mutations. We present data of chromosome aberration analyses from lymphocyte metaphase spreads of ISS crew members participating in short term (10-14 days) or long term (around 6 months) missions. From each subject we received two blood samples. The first sample was drawn about 10 days before launch and a second one within 3 days after return from flight. From lymphocyte cultures metaphase plates were prepared on glass slides. Giemsa stained and in situ hybridised metaphases were scored for chromosome changes in pre-flight and post-flight blood samples and the mutation rates were compared. Results obtained in chromosomal studies on long-term flight crew members showed pronounced inter-individual differences in the response to elevated radiation levels. Overall slight but significant elevations of typical radiation induced aberrations, i.e., dicentric chromosomes and reciprocal translocations have been observed. Our data indicate no elevation of mutation rates due to short term stays on-board the ISS.

  4. What is the role of dopamine in reward: hedonic impact, reward learning, or incentive salience?

    Berridge, K C; Robinson, T E

    1998-12-01

    What roles do mesolimbic and neostriatal dopamine systems play in reward? Do they mediate the hedonic impact of rewarding stimuli? Do they mediate hedonic reward learning and associative prediction? Our review of the literature, together with results of a new study of residual reward capacity after dopamine depletion, indicates the answer to both questions is 'no'. Rather, dopamine systems may mediate the incentive salience of rewards, modulating their motivational value in a manner separable from hedonia and reward learning. In a study of the consequences of dopamine loss, rats were depleted of dopamine in the nucleus accumbens and neostriatum by up to 99% using 6-hydroxydopamine. In a series of experiments, we applied the 'taste reactivity' measure of affective reactions (gapes, etc.) to assess the capacity of dopamine-depleted rats for: 1) normal affect (hedonic and aversive reactions), 2) modulation of hedonic affect by associative learning (taste aversion conditioning), and 3) hedonic enhancement of affect by non-dopaminergic pharmacological manipulation of palatability (benzodiazepine administration). We found normal hedonic reaction patterns to sucrose vs. quinine, normal learning of new hedonic stimulus values (a change in palatability based on predictive relations), and normal pharmacological hedonic enhancement of palatability. We discuss these results in the context of hypotheses and data concerning the role of dopamine in reward. We review neurochemical, electrophysiological, and other behavioral evidence. We conclude that dopamine systems are not needed either to mediate the hedonic pleasure of reinforcers or to mediate predictive associations involved in hedonic reward learning. We conclude instead that dopamine may be more important to incentive salience attributions to the neural representations of reward-related stimuli. Incentive salience, we suggest, is a distinct component of motivation and reward. In other words, dopamine systems are necessary

  5. Aberrant splicing and drug resistance in AML.

    de Necochea-Campion, Rosalia; Shouse, Geoffrey P; Zhou, Qi; Mirshahidi, Saied; Chen, Chien-Shing

    2016-01-01

    The advent of next-generation sequencing technologies has unveiled a new window into the heterogeneity of acute myeloid leukemia (AML). In particular, recurrent mutations in spliceosome machinery and genome-wide aberrant splicing events have been recognized as a prominent component of this disease. This review will focus on how these factors influence drug resistance through altered splicing of tumor suppressor and oncogenes and dysregulation of the apoptotic signaling network. A better understanding of these factors in disease progression is necessary to design appropriate therapeutic strategies recognizing specific alternatively spliced or mutated oncogenic targets. PMID:27613060

  6. Aberrations in Fresnel Lenses and Mirrors

    Gregory, Don

    1999-01-01

    The NASA/MSFC Shooting Star program revealed a number of technical problems that must be solved before solar thermal propulsion can become a reality. The fundamental problem of interest here is the collection of solar energy. This is the first step in the propulsion process and indeed the most important. Everything else depends on the efficiency and focusing ability of the collection lens or mirror. An initial model of Fresnel lens behavior using a wave optics approach has been completed and the results were encouraging enough to warrant an experimental investigation. This experimental investigation confirmed some of the effects predicted and produced invaluable photographic evidence of coherence based diffraction and aberration.

  7. The Birth of Words: Ten-Month-Olds Learn Words Through Perceptual Salience

    Pruden, Shannon M.; Hirsh-Pasek, Kathy; Golinkoff, Roberta Michnick; Hennon, Elizabeth A.

    2006-01-01

    A core task in language acquisition is mapping words onto objects, actions, and events. Two studies investigated how children learn to map novel labels onto novel objects. Study 1 investigated whether 10-month-olds use both perceptual and social cues to learn a word. Study 2, a control study, tested whether infants paired the label with a particular spatial location rather than to an object. Results show that 10-month-olds can learn new labels and do so by relying on the perceptual salience o...

  8. Advert saliency distracts children's visual attention during task-oriented internet use

    NilsHolmberg

    2014-01-01

    The general research question of the present study was to assess the impact of visually salient online adverts on children's task-oriented internet use. In order to answer this question, an experimental study was constructed in which 9-year-old and 12-year-old Swedish children were asked to solve a number of tasks while interacting with a mockup website. In each trial, web adverts in several saliency conditions were presented. By both measuring children's task accuracy, as well as the visual ...

  9. Thinking about Race: The Salience of Racial Identity at Two-and Four-Year Colleges and the Climate for Diversity

    Hurtado, Sylvia; Alvarado, Adriana Ruiz; Guillermo-Wann, Chelsea

    2015-01-01

    Racial identity salience is an important component of identity development that is associated with a number of educational outcomes. Using the Diverse Learning Environments Survey, this study identifies precollege and college experiences that contribute to a heightened salience of racial identity, and its relationship to perceptions of campus…

  10. Development of Rostral Prefrontal Cortex and Cognitive and Behavioural Disorders

    Dumontheil, Iroise; Burgess, Paul W.; Blakemore, Sarah-Jayne

    2008-01-01

    Information on the development and functions of rostral prefrontal cortex (PFC), or Brodmann area 10, has been gathered from different fields, from anatomical development to functional neuroimaging in adults, and put forward in relation to three particular cognitive and behavioural disorders. Rostral PFC is larger and has a lower cell density in…

  11. The impact of social disparity on prefrontal function in childhood.

    Margaret A Sheridan

    Full Text Available The prefrontal cortex (PFC develops from birth through late adolescence. This extended developmental trajectory provides many opportunities for experience to shape the structure and function of the PFC. To date, a few studies have reported links between parental socioeconomic status (SES and prefrontal function in childhood, raising the possibility that aspects of environment associated with SES impact prefrontal function. Considering that behavioral measures of prefrontal function are associated with learning across multiple domains, this is an important area of investigation. In this study, we used fMRI to replicate previous findings, demonstrating an association between parental SES and PFC function during childhood. In addition, we present two hypothetical mechanisms by which SES could come to affect PFC function of this association: language environment and stress reactivity. We measured language use in the home environment and change in salivary cortisol before and after fMRI scanning. Complexity of family language, but not the child's own language use, was associated with both parental SES and PFC activation. Change in salivary cortisol was also associated with both SES and PFC activation. These observed associations emphasize the importance of both enrichment and adversity-reduction interventions in creating good developmental environments for all children.

  12. Unconscious errors enhance prefrontal-occipital oscillatory synchrony

    M.X. Cohen; S. van Gaal; K.R. Ridderinkhof; V.A.F. Lamme

    2009-01-01

    The medial prefrontal cortex (MFC) is critical for our ability to learn from previous mistakes. Here we provide evidence that neurophysiological oscillatory long-range synchrony is a mechanism of post-error adaptation that occurs even without conscious awareness of the error. During a visually signa

  13. Prefrontal cortical minicolumn: from executive control to disrupted cognitive processing.

    Opris, Ioan; Casanova, Manuel F

    2014-07-01

    The prefrontal cortex of the primate brain has a modular architecture based on the aggregation of neurons in minicolumnar arrangements having afferent and efferent connections distributed across many brain regions to represent, select and/or maintain behavioural goals and executive commands. Prefrontal cortical microcircuits are assumed to play a key role in the perception to action cycle that integrates relevant information about environment, and then selects and enacts behavioural responses. Thus, neurons within the interlaminar microcircuits participate in various functional states requiring the integration of signals across cortical layers and the selection of executive variables. Recent research suggests that executive abilities emerge from cortico-cortical interactions between interlaminar prefrontal cortical microcircuits, whereas their disruption is involved in a broad spectrum of neurologic and psychiatric disorders such as autism, schizophrenia, Alzheimer's and drug addiction. The focus of this review is on the structural, functional and pathological approaches involving cortical minicolumns. Based on recent technological progress it has been demonstrated that microstimulation of infragranular cortical layers with patterns of microcurrents derived from supragranular layers led to an increase in cognitive performance. This suggests that interlaminar prefrontal cortical microcircuits are playing a causal role in improving cognitive performance. An important reason for the new interest in cortical modularity comes from both the impressive progress in understanding anatomical, physiological and pathological facets of cortical microcircuits and the promise of neural prosthetics for patients with neurological and psychiatric disorders. PMID:24531625

  14. Extinction Circuits for Fear and Addiction Overlap in Prefrontal Cortex

    Peters, Jamie; Kalivas, Peter W.; Quirk, Gregory J.

    2009-01-01

    Extinction is a form of inhibitory learning that suppresses a previously conditioned response. Both fear and drug seeking are conditioned responses that can lead to maladaptive behavior when expressed inappropriately, manifesting as anxiety disorders and addiction, respectively. Recent evidence indicates that the medial prefrontal cortex (mPFC) is…

  15. Dissociable prefrontal brain systems for attention and emotion

    Yamasaki, Hiroshi; Labar, Kevin S.; McCarthy, Gregory

    2002-08-01

    The prefrontal cortex has been implicated in a variety of attentional, executive, and mnemonic mental operations, yet its functional organization is still highly debated. The present study used functional MRI to determine whether attentional and emotional functions are segregated into dissociable prefrontal networks in the human brain. Subjects discriminated infrequent and irregularly presented attentional targets (circles) from frequent standards (squares) while novel distracting scenes, parametrically varied for emotional arousal, were intermittently presented. Targets differentially activated middle frontal gyrus, posterior parietal cortex, and posterior cingulate gyrus. Novel distracters activated inferior frontal gyrus, amygdala, and fusiform gyrus, with significantly stronger activation evoked by the emotional scenes. The anterior cingulate gyrus was the only brain region with equivalent responses to attentional and emotional stimuli. These results show that attentional and emotional functions are segregated into parallel dorsal and ventral streams that extend into prefrontal cortex and are integrated in the anterior cingulate. These findings may have implications for understanding the neural dynamics underlying emotional distractibility on attentional tasks in affective disorders. novelty | prefrontal cortex | amygdala | cingulate gyrus

  16. Sensitivity of singular beams in the presence of Zernike aberrations

    Dixit, Awakash; Mishra, Sanjay Kumar; Gupta, Arun Kumar

    2015-08-01

    Singular beams in the presence of Zernike aberrations create an opportunity for various applications such as trapping and manipulation of micro-particles, atomic optics and atmospheric optics. In the milieu of importance of the role of aberrations, sensitivity of singular beams with Zernike aberrations is studied. In this paper, the effect of various Zernike aberrations on a singular beam is reported in terms of its Point Spread Function (PSF) deformations. The intensity distributions around the focal plane, i.e. PSF, of the singular beam of various topological charges and in the presence of different strengths of Zernike aberrations are theoretically estimated by the Huygens-Fresnel diffraction integral. Experimentally, the singular beams have been generated and known strengths of Zernike aberration introduced in the beam by a phase-only Spatial Light Modulator. Metric Ensquared Energy is used to analyze the PSF of the corresponding intensity distributions of the singular beams. The experimental results have been validated with numerical simulation.

  17. Calculation of aberration of electron gun in color picture tubes

    In a color picture tube, aberration is an important factor influencing the electron beam spot on the screen. This paper discusses a new method which is used to calculate the aberration of an electron gun in a CPT. In this method, electron trajectories are simulated directly in the cathode and the pre-focus lens. In the main lens, the asymptotic aberration is calculated to decide the size of the image. Some results of the calculation are shown in this paper. (orig.)

  18. Monitoring of chromosomal aberrations in natural populations of Pinus pallasiana

    V. P. Koba

    2012-01-01

    This paper presents the results of monitoring research of the chromosome aberrations at the stage of anaphase-telophase. The statistical characteristics of dynamics of chromosomal aberrations in populations of Pinus pallasiana D. Don across the high-altitude zones of the Mountain Crimea is given. It is established that on the southern macroslope of the Crimean Main Ridge the frequency of chromosomal aberrations in the P. pallasiana stands is higher in the lower zone in comparison with the mid...

  19. Aberrations caused by mechanical misalignments in electrostatic quadrupole lens systems

    Baranova, L. A.; Read, F. H.

    Image aberrations resulting from small misalignments in quadrupole lenses multiplets have been analysed. Analytical formulas for the coefficients of the beam displacement, astigmatism and coma associated with misalignments in a general quadrupole lens system have been derived. Numerical computations of systems of three and four quadrupole lenses have also been carried out. The aberration figures obtained for systems with and without a mechanical defect are compared. The aberration coefficients that have been obtained can be used for estimating tolerance limits for lens misalignments.

  20. Chromosomal aberrations in children exposed to diagnostic x-rays

    Among children who have received high x-ray doses congenital dislocation of the hip joint is the predominating diagnosis. In a series of 9 children who had received high x-ray doses (8 with luxation of the hip joint and one with achondroplasia) a significant increase of chromosomal aberrations was found. The increase concerned mainly chromosome type aberrations. The shorter the time since the last x-ray investigation the higher was the frequency of chromosome type aberrations. (author)

  1. Hydronephrosis by an Aberrant Renal Artery: A Case Report

    Park, Byoung Seok; Jeong, Taek Kyun; Ma, Seong Kwon; Kim, Soo Wan; Kim, Nam Ho; Choi, Ki Chul; Jeong, Yong Yeon

    2003-01-01

    Ureteropelvic junction obstruction is usually intrinsic and is most common in children. Aberrant renal arteries are present in about 30% of individuals. Aberrant renal arteries to the inferior pole cross anteriorly to the ureter and may cause hydronephrosis. To the best of our knowledge, although there are some papers about aberrant renal arteries producing ureteropelvic junction obstruction, there is no report of a case which is diagnosed by the new modalities, such as computed tomography an...

  2. Pattern of Chromosomal Aberrations in Patients from North East Iran

    Saeedeh Ghazaey; Farzaneh Mirzaei; Mitra Ahadian; Fatemeh Keifi; Semiramis Tootian; Mohammad Reza Abbaszadegan

    2013-01-01

    Objective: Chromosomal aberrations are common causes of multiple anomaly syndromes. Recurrent chromosomal aberrations have been identified by conventional cytogenetic methods used widely as one of the most important clinical diagnostic techniques. Materials and Methods: In this retrospective study, the incidences of chromosomal aberrations were evaluated in a six year period from 2005 to 2011 in Pardis Clinical and Genetics Laboratory on patients referred to from Mashhad and other cities in K...

  3. Protein Kinase C Overactivity Impairs Prefrontal Cortical Regulation of Working Memory

    Birnbaum, S. G.; Yuan, P. X.; Wang, M.; Vijayraghavan, S.; Bloom, A. K.; Davis, D. J.; Gobeske, K. T.; Sweatt, J. D.; Manji, H. K.; Arnsten, A. F. T.

    2004-10-01

    The prefrontal cortex is a higher brain region that regulates thought, behavior, and emotion using representational knowledge, operations often referred to as working memory. We tested the influence of protein kinase C (PKC) intracellular signaling on prefrontal cortical cognitive function and showed that high levels of PKC activity in prefrontal cortex, as seen for example during stress exposure, markedly impair behavioral and electrophysiological measures of working memory. These data suggest that excessive PKC activation can disrupt prefrontal cortical regulation of behavior and thought, possibly contributing to signs of prefrontal cortical dysfunction such as distractibility, impaired judgment, impulsivity, and thought disorder.

  4. Chromosome aberration analysis for biological dosimetry: a review

    Among various biological dosimetry techniques, dicentric chromosome aberration method appears to be the method of choice in analysing accidental radiation exposure in most of the laboratories. The major advantage of this method is its sensitivity as the number of dicentric chromosomes present in control population is too small and more importantly radiation induces mainly dicentric chromosome aberration among unstable aberration. This report brings out the historical development of various cytogenetic methods, the basic structure of DNA, chromosomes and different forms of chromosome aberrations. It also highlights the construction of dose-response curve for dicentric chromosome and its use in the estimation of radiation dose. (author)

  5. Cellular origin of prognostic chromosomal aberrations in AML patients

    Mora-Jensen, H.; Jendholm, J.; Rapin, N.;

    2015-01-01

    these aberrations occur in normal hematopoietic stem and progenitor cells (HSCs/HPCs) before definitive leukemic transformation through additional acquisition of a few (that is, mostly 1 or 2) leukemia-promoting driver aberrations. NGS studies on sorted bone marrow (BM) populations of AML patients with...... molecular aberrations that were present in the fully transformed committed HPCs together with the prognostic driver aberration. Adding to this vast heterogeneity and complexity of AML genomes and their clonal evolution, a recent study of a murine AML model demonstrated that t(9;11) AML originating from HSCs...

  6. Evidence inhibition responds reactively to the salience of distracting information during focused attention.

    Natalie Wyatt

    Full Text Available Along with target amplification, distractor inhibition is regarded as a major contributor to selective attention. Some theories suggest that the strength of inhibitory processing is proportional to the salience of the distractor (i.e., inhibition reacts to the distractor intensity. Other theories suggest that the strength of inhibitory processing does not depend on the salience of the distractor (i.e., inhibition does not react to the distractor intensity. The present study aimed to elucidate the relationship between the intensity of a distractor and its subsequent inhibition during focused attention. A flanker task with a variable distractor-target stimulus-onset asynchrony (SOA was used to measure both distractor interference and distractor inhibition. We manipulated the intensity of the distractor in two separate ways, by varying its distance from the target (Experiment 1 and by varying its brightness (Experiment 2. The results indicate that more intense distractors were associated with both increased interference and stronger distractor inhibition. The latter outcome provides novel support for the reactive inhibition hypothesis, which posits that inhibition reacts to the strength of distractor input, such that more salient distractors elicit stronger inhibition.

  7. A Sea-Sky Line Detection Method for Unmanned Surface Vehicles Based on Gradient Saliency

    Bo Wang

    2016-04-01

    Full Text Available Special features in real marine environments such as cloud clutter, sea glint and weather conditions always result in various kinds of interference in optical images, which make it very difficult for unmanned surface vehicles (USVs to detect the sea-sky line (SSL accurately. To solve this problem a saliency-based SSL detection method is proposed. Through the computation of gradient saliency the line features of SSL are enhanced effectively, while other interference factors are relatively suppressed, and line support regions are obtained by a region growing method on gradient orientation. The SSL identification is achieved according to region contrast, line segment length and orientation features, and optimal state estimation of SSL detection is implemented by introducing a cubature Kalman filter (CKF. In the end, the proposed method is tested on a benchmark dataset from the “XL” USV in a real marine environment, and the experimental results demonstrate that the proposed method is significantly superior to other state-of-the-art methods in terms of accuracy rate and real-time performance, and its accuracy and stability are effectively improved by the CKF.

  8. A Sea-Sky Line Detection Method for Unmanned Surface Vehicles Based on Gradient Saliency.

    Wang, Bo; Su, Yumin; Wan, Lei

    2016-01-01

    Special features in real marine environments such as cloud clutter, sea glint and weather conditions always result in various kinds of interference in optical images, which make it very difficult for unmanned surface vehicles (USVs) to detect the sea-sky line (SSL) accurately. To solve this problem a saliency-based SSL detection method is proposed. Through the computation of gradient saliency the line features of SSL are enhanced effectively, while other interference factors are relatively suppressed, and line support regions are obtained by a region growing method on gradient orientation. The SSL identification is achieved according to region contrast, line segment length and orientation features, and optimal state estimation of SSL detection is implemented by introducing a cubature Kalman filter (CKF). In the end, the proposed method is tested on a benchmark dataset from the "XL" USV in a real marine environment, and the experimental results demonstrate that the proposed method is significantly superior to other state-of-the-art methods in terms of accuracy rate and real-time performance, and its accuracy and stability are effectively improved by the CKF. PMID:27092503

  9. LexRank: Graph-based Lexical Centrality as Salience in Text Summarization

    Erkan, G; 10.1613/jair.1523

    2011-01-01

    We introduce a stochastic graph-based method for computing relative importance of textual units for Natural Language Processing. We test the technique on the problem of Text Summarization (TS). Extractive TS relies on the concept of sentence salience to identify the most important sentences in a document or set of documents. Salience is typically defined in terms of the presence of particular important words or in terms of similarity to a centroid pseudo-sentence. We consider a new approach, LexRank, for computing sentence importance based on the concept of eigenvector centrality in a graph representation of sentences. In this model, a connectivity matrix based on intra-sentence cosine similarity is used as the adjacency matrix of the graph representation of sentences. Our system, based on LexRank ranked in first place in more than one task in the recent DUC 2004 evaluation. In this paper we present a detailed analysis of our approach and apply it to a larger data set including data from earlier DUC evaluatio...

  10. VSI: a visual saliency-induced index for perceptual image quality assessment.

    Zhang, Lin; Shen, Ying; Li, Hongyu

    2014-10-01

    Perceptual image quality assessment (IQA) aims to use computational models to measure the image quality in consistent with subjective evaluations. Visual saliency (VS) has been widely studied by psychologists, neurobiologists, and computer scientists during the last decade to investigate, which areas of an image will attract the most attention of the human visual system. Intuitively, VS is closely related to IQA in that suprathreshold distortions can largely affect VS maps of images. With this consideration, we propose a simple but very effective full reference IQA method using VS. In our proposed IQA model, the role of VS is twofold. First, VS is used as a feature when computing the local quality map of the distorted image. Second, when pooling the quality score, VS is employed as a weighting function to reflect the importance of a local region. The proposed IQA index is called visual saliency-based index (VSI). Several prominent computational VS models have been investigated in the context of IQA and the best one is chosen for VSI. Extensive experiments performed on four large-scale benchmark databases demonstrate that the proposed IQA index VSI works better in terms of the prediction accuracy than all state-of-the-art IQA indices we can find while maintaining a moderate computational complexity. The MATLAB source code of VSI and the evaluation results are publicly available online at http://sse.tongji.edu.cn/linzhang/IQA/VSI/VSI.htm. PMID:25122572

  11. Localization and Classification of Paddy Field Pests using a Saliency Map and Deep Convolutional Neural Network.

    Liu, Ziyi; Gao, Junfeng; Yang, Guoguo; Zhang, Huan; He, Yong

    2016-01-01

    We present a pipeline for the visual localization and classification of agricultural pest insects by computing a saliency map and applying deep convolutional neural network (DCNN) learning. First, we used a global contrast region-based approach to compute a saliency map for localizing pest insect objects. Bounding squares containing targets were then extracted, resized to a fixed size, and used to construct a large standard database called Pest ID. This database was then utilized for self-learning of local image features which were, in turn, used for classification by DCNN. DCNN learning optimized the critical parameters, including size, number and convolutional stride of local receptive fields, dropout ratio and the final loss function. To demonstrate the practical utility of using DCNN, we explored different architectures by shrinking depth and width, and found effective sizes that can act as alternatives for practical applications. On the test set of paddy field images, our architectures achieved a mean Accuracy Precision (mAP) of 0.951, a significant improvement over previous methods. PMID:26864172

  12. From intrusive thoughts to obsessions: The role of perceptions of responsibility, salience, and thought suppression.

    Fritzler, Bryan; Hecker, Jeffrey E; Fawzy, Tamer I

    2008-12-01

    Salkovskis [1985. Obsessional-compulsive problems: A cognitive-behavioural analysis. Behaviour Research and Therapy, 23, 571-583.] hypothesized that intrusive thoughts are more likely to occur if the thought is salient for the individual, triggers feelings of responsibility and if the individual attempts to suppress the thought. The relationship between these three factors (responsibility, salience, thought suppression) and frequency of intrusive thoughts as well as anxiety were examined in the present study. One hundred female college students were led to believe that a snake had escaped from the cage in which it was housed. Half of the participants were led to believe that they were responsible for the snake's escape and half were not (Responsibility/No Responsibility). Half of the participants in each Responsibility condition were instructed to suppress thoughts of snakes during a stream of consciousness exercise and half were not (Thought Suppression vs. No Thought Suppression). All participants then completed a second stream of consciousness without suppression instructions. Salience groups were determined by a median split on a measure of snake fearfulness. Participants for whom the snake was a salient stimulus and who believed that they were responsible for the snake's escape had the highest frequency of snake thoughts during the second stream of consciousness task and also experienced the highest levels of state anxiety. Findings are discussed with respect to Salkovskis' model. PMID:18423568

  13. A robust infrared dim target detection method based on template filtering and saliency extraction

    Wang, Wenguang; Li, Chenming; Shi, Jianing

    2015-11-01

    Dim target detection in infrared image with complex background and low signal-clutter ratio (SCR) is a significant and difficult task in the infrared target tracking system. A robust infrared dim target detection method based on template filtering and saliency extraction is proposed in this paper. The weighted gray map is obtained from the infrared image to highlight the target which is brighter than its neighbors and has weak correlation with its background. The target saliency map is then calculated by phase spectrum of Fourier Transform, so that the dim target detection could be converted to salient region extraction. The potential targets are finally extracted by combining the two maps. Moreover, position discrimination between targets in the two maps is used to exclude the false alarms and extract the targets. Experimental results on measured images indicate that our method is feasible, adaptable and robust in different backgrounds. The ROC (Receiver Operating Characteristic) curves obtained from the simulated images demonstrate the proposed method outperforms some existing typical methods in both detection rate and false alarm rate, for target detection with low SCR.

  14. Power and death: Mortality salience increases power seeking while feeling powerful reduces death anxiety.

    Belmi, Peter; Pfeffer, Jeffrey

    2016-05-01

    According to Terror Management Theory, people respond to reminders of mortality by seeking psychological security and bolstering their self-esteem. Because previous research suggests that having power can provide individuals a sense of security and self-worth, we hypothesize that mortality salience leads to an increased motivation to acquire power, especially among men. Study 1 found that men (but not women) who wrote about their death reported more interest in acquiring power. Study 2A and Study 2B demonstrated that when primed with reminders of death, men (but not women) reported behaving more dominantly during the subsequent week, while both men and women reported behaving more prosocially during that week. Thus, mortality salience prompts people to respond in ways that help them manage their death anxiety but in ways consistent with normative gender expectations. Furthermore, Studies 3-5 showed that feeling powerful reduces anxiety when mortality is salient. Specifically, we found that when primed to feel more powerful, both men and women experienced less mortality anxiety. (PsycINFO Database Record PMID:26867106

  15. Saliency-aware food image segmentation for personal dietary assessment using a wearable computer

    Image-based dietary assessment has recently received much attention in the community of obesity research. In this assessment, foods in digital pictures are specified, and their portion sizes (volumes) are estimated. Although manual processing is currently the most utilized method, image processing holds much promise since it may eventually lead to automatic dietary assessment. In this paper we study the problem of segmenting food objects from images. This segmentation is difficult because of various food types, shapes and colors, different decorating patterns on food containers, and occlusions of food and non-food objects. We propose a novel method based on a saliency-aware active contour model (ACM) for automatic food segmentation from images acquired by a wearable camera. An integrated saliency estimation approach based on food location priors and visual attention features is designed to produce a salient map of possible food regions in the input image. Next, a geometric contour primitive is generated and fitted to the salient map by means of multi-resolution optimization with respect to a set of affine and elastic transformation parameters. The food regions are then extracted after contour fitting. Our experiments using 60 food images showed that the proposed method achieved significantly higher accuracy in food segmentation when compared to conventional segmentation methods. (paper)

  16. Transmitting the sum of all fears: Iranian nuclear threat salience among offspring of Holocaust survivors.

    Shrira, Amit

    2015-07-01

    Many Israelis are preoccupied with the prospect of a nuclear-armed Iran, frequently associating it with the danger of annihilation that existed during the Holocaust. The current article examined whether offspring of Holocaust survivors (OHS) are especially preoccupied and sensitive to the Iranian threat, and whether this susceptibility is a part of their increased general image of actual and potential threats, defined as the hostile world scenario (HWS). Study 1 (N = 106) showed that relative to comparisons, OHS reported more preoccupation with the Iranian nuclear threat. Moreover, the positive relationship between the salience of the Iranian threat and symptoms of anxiety was stronger among OHS. Study 2 (N = 450) replicated these findings, while focusing on the Iranian nuclear threat salience and symptoms of psychological distress. It further showed that OHS reported more negative engagement with the HWS (i.e., feeling that surrounding threats decrease one's sense of competence), which in turn mediated their increased preoccupation with the Iranian threat. The results suggest that intergenerational transmission of the Holocaust trauma includes heightened preoccupation with and sensitivity to potential threats of annihilation, and that the specific preoccupation with threats of annihilation reflects a part of a more general preoccupation with surrounding threats. PMID:25793401

  17. Saliency-aware food image segmentation for personal dietary assessment using a wearable computer

    Chen, Hsin-Chen; Jia, Wenyan; Sun, Xin; Li, Zhaoxin; Li, Yuecheng; Fernstrom, John D.; Burke, Lora E.; Baranowski, Thomas; Sun, Mingui

    2015-02-01

    Image-based dietary assessment has recently received much attention in the community of obesity research. In this assessment, foods in digital pictures are specified, and their portion sizes (volumes) are estimated. Although manual processing is currently the most utilized method, image processing holds much promise since it may eventually lead to automatic dietary assessment. In this paper we study the problem of segmenting food objects from images. This segmentation is difficult because of various food types, shapes and colors, different decorating patterns on food containers, and occlusions of food and non-food objects. We propose a novel method based on a saliency-aware active contour model (ACM) for automatic food segmentation from images acquired by a wearable camera. An integrated saliency estimation approach based on food location priors and visual attention features is designed to produce a salient map of possible food regions in the input image. Next, a geometric contour primitive is generated and fitted to the salient map by means of multi-resolution optimization with respect to a set of affine and elastic transformation parameters. The food regions are then extracted after contour fitting. Our experiments using 60 food images showed that the proposed method achieved significantly higher accuracy in food segmentation when compared to conventional segmentation methods.

  18. Salience Effects: L2 Sentence Production as a Window on L1 Speech Planning.

    Antón-Méndez, Inés; Gerfen, Chip; Ramos, Miguel

    2016-06-01

    Salience influences grammatical structure during production in a language-dependent manner because different languages afford different options to satisfy preferences. During production, speakers may always try to satisfy all syntactic encoding preferences (e.g., salient entities to be mentioned early, themes to be assigned the syntactic function of object) and adjust when this is not possible (e.g., a salient theme in English) or, alternatively, they may learn early on to associate particular conceptual configurations with particular syntactic frames (e.g., salient themes with passives). To see which of these alternatives is responsible for the production of passives when dealing with a salient theme, we looked at the second language effects of salience for English-speaking learners of Spanish, where the two preferences can be satisfied simultaneously by fronting the object (Prat-Sala and Branigan in J Mem Lang 42:168-182, 2000). In accordance with highly incremental models of language production, English speakers appear to quickly make use of the alternatives in the second language that allow observance of more processing preferences. PMID:25822758

  19. Change blindness in pigeons (Columba livia): the effects of change salience and timing.

    Herbranson, Walter T

    2015-01-01

    Change blindness is a well-established phenomenon in humans, in which plainly visible changes in the environment go unnoticed. Recently a parallel change blindness phenomenon has been demonstrated in pigeons. The reported experiment follows up on this finding by investigating whether change salience affects change blindness in pigeons the same way it affects change blindness in humans. Birds viewed alternating displays of randomly generated lines back-projected onto three response keys, with one or more line features on a single key differing between consecutive displays. Change salience was manipulated by varying the number of line features that changed on the critical response key. Results indicated that change blindness is reduced if a change is made more salient, and this matches previous human results. Furthermore, accuracy patterns indicate that pigeons' effective search area expanded over the course of a trial to encompass a larger portion of the stimulus environment. Thus, the data indicate two important aspects of temporal cognition. First, the timing of a change has a profound influence on whether or not that change will be perceived. Second, pigeons appear to engage in a serial search for changes, in which additional time is required to search additional locations. PMID:26284021

  20. Change Blindness in Pigeons (Columba livia: the Effects of Change Salience and Timing

    Walter Troy Herbranson

    2015-08-01

    Full Text Available Change blindness is a well-established phenomenon in humans, in which plainly visible changes in the environment go unnoticed. Recently a parallel change blindness phenomenon has been demonstrated in pigeons. The reported experiment follows up on this finding by investigating whether change salience affects change blindness in pigeons the same way it affects change blindness in humans. Birds viewed alternating displays of randomly generated lines back-projected onto three response keys, with one or more line features on a single key differing between consecutive displays. Change salience was manipulated by varying the number of line features that changed on the critical response key. Results indicated that change blindness is reduced if a change is made more salient, and this matches previous human results. Furthermore, accuracy patterns indicate that pigeons’ effective search area expanded over the course of a trial to encompass a larger portion of the stimulus environment. Thus, the data indicate two important aspects of temporal cognition. First, the timing of a change has a profound influence on whether or not that change will be perceived. Second, pigeons appear to engage in a serial search for changes, in which additional time is required to search additional locations.

  1. Aberrant angiogenesis: The gateway to diabetic complications

    Sunil K Kota

    2012-01-01

    Full Text Available Diabetes Mellitus is a metabolic cum vascular syndrome with resultant abnormalities in both micro- and macrovasculature. The adverse long-term effects of diabetes mellitus have been described to involve many organ systems. Apart from hyperglycemia, abnormalities of angiogenesis may cause or contribute toward many of the clinical manifestations of diabetes. These are implicated in the pathogenesis of vascular abnormalities of the retina, kidneys, and fetus, impaired wound healing, increased risk of rejection of transplanted organs, and impaired formation of coronary collaterals. A perplexing feature of the aberrant angiogenesis is that excessive and insufficient angiogenesis can occur in different organs in the same individual. The current article hereby reviews the molecular mechanisms including abnormalities in growth factors, cytokines, and metabolic derangements, clinical implications, and therapeutic options of dealing with abnormal angiogenesis in diabetes.

  2. Aberrant neurocognitive processing of fear in young girls with Turner syndrome

    Bray, Signe; Haas, Brian W.; Hoeft, Fumiko; Reiss, Allan L.

    2014-01-01

    Appraisal of fearful stimuli is an integral aspect of social cognition. Neural circuitry underlying this phenomenon has been well-described and encompasses a distributed network of affective and cognitive nodes. Interestingly, this ability to process fearful faces is impaired in Turner syndrome (TS), a genetic disorder of females in which all or part of an X chromosome is missing. However, neurofunctional correlates for this impairment have not been well-studied, particularly in young girls. Given that the core features of TS include X chromosome gene haploinsufficiency and secondary sex hormone deficiencies, investigation of fearful face processing may provide insights into the influence of X chromosome gene expression on this network. Therefore, we examined behavioral and neural responses during an explicit emotional face labeling task in 14 prepubertal girls with TS and 16 typically developing age-matched controls (6–13 years). We demonstrate that girls with TS have a specific impairment in the identification of fearful faces and show decreased activation in several cognitive control regions, including the anterior dorsal anterior cingulate cortex, dorsolateral prefrontal cortex and posterior cingulate gyrus. Our results indicate that aberrant functional activation in dorsal cognitive regions plays an integral role in appraisal of, and regulation of response to fear in TS. PMID:23171616

  3. Response variability of frontal eye field neurons modulates with sensory input and saccade preparation but not visual search salience.

    Purcell, Braden A; Heitz, Richard P; Cohen, Jeremiah Y; Schall, Jeffrey D

    2012-11-01

    Discharge rate modulation of frontal eye field (FEF) neurons has been identified with a representation of visual search salience (physical conspicuity and behavioral relevance) and saccade preparation. We tested whether salience or saccade preparation are evident in the trial-to-trial variability of discharge rate. We quantified response variability via the Fano factor in FEF neurons recorded in monkeys performing efficient and inefficient visual search tasks. Response variability declined following stimulus presentation in most neurons, but despite clear discharge rate modulation, variability did not change with target salience. Instead, we found that response variability was modulated by stimulus luminance and the number of items in the visual field independently of attentional demands. Response variability declined to a minimum before saccade initiation, and presaccadic response variability was directionally tuned. In addition, response variability was correlated with the response time of memory-guided saccades. These results indicate that the trial-by-trial response variability of FEF neurons reflects saccade preparation and the strength of sensory input, but not visual search salience or attentional allocation. PMID:22956785

  4. Role Salience, Social Support, and Work-Family Conflict among Jewish and Arab Female Teachers in Israel

    Cinamon, Rachel Gali

    2009-01-01

    Conceptualizing career development in a cultural and contextual framework, this study examined within-gender differences in role salience and work-family conflict (WFC) among 101 Jewish and 99 Arab female teachers (aged 23-64 years) from central Israel. The contribution of social support to women's conflict was also examined. Results highlighted…

  5. Mortality Salience and Positive Affect Influence Adolescents' Attitudes toward Peers with Physical Disabilities: Terror Management and Broaden and Build Theories

    Taubman-Ben-Ari, Orit; Eherenfreund-Hager, Ahinoam; Findler, Liora

    2011-01-01

    Attitudes toward teenagers with and without physical disabilities, and their social acceptance, were examined from the perspective of terror management theory and the broaden and build theory. Participants (n = 390, aged 13-17) were divided into 3 experimental conditions: positive emotions, mortality salience, and control. Then, they were shown…

  6. When are stockpiled products consumed faster? A convenience-salience framework of postpurchase consumption incidence and quantity

    Chandon, P.; Wansink, B.

    2002-01-01

    When people stockpile products, how do they decide when and how much they will consume? To answer this question, the authors develop a framework that shows how the salience and convenience of products influence postpurchase consumption incidence and quantity. Multiple research methods¿including scan

  7. Affecting Girls' Activity and Job Interests through Play: The Moderating Roles of Personal Gender Salience and Game Characteristics

    Coyle, Emily F.; Liben, Lynn S.

    2016-01-01

    Gender schema theory (GST) posits that children approach opportunities perceived as gender appropriate, avoiding those deemed gender inappropriate, in turn affecting gender-differentiated career trajectories. To test the hypothesis that children's gender salience filters (GSF--tendency to attend to gender) moderate these processes, 62 preschool…

  8. The Roles of Feature-Specific Task Set and Bottom-Up Salience in Attentional Capture: An ERP Study

    Eimer, Martin; Kiss, Monika; Press, Clare; Sauter, Disa

    2009-01-01

    We investigated the roles of top-down task set and bottom-up stimulus salience for feature-specific attentional capture. Spatially nonpredictive cues preceded search arrays that included a color-defined target. For target-color singleton cues, behavioral spatial cueing effects were accompanied by cue-induced N2pc components, indicative of…

  9. Resting-state functional connectivity abnormalities in limbic and salience networks in social anxiety disorder without comorbidity

    Pannekoek, J. Nienke; Veer, Ilya M.; van Tol, Marie-Jose; van der Werff, Steven J. A.; Demenescu, Liliana R.; Aleman, Andre; Veltman, Dick J.; Zitman, Frans G.; Rombouts, Serge A. R. B.; van der Wee, Nic J. A.

    2013-01-01

    The neurobiology of social anxiety disorder (SAD) is not yet fully understood. Structural and functional neuroimaging studies in SAD have identified abnormalities in various brain areas, particularly the amygdala and elements of the salience network. This study is the first to examine resting-state

  10. Using nodal aberration theory to understand the aberrations of multiple unobscured three mirror anastigmatic (TMA) telescopes

    Thompson, Kevin P.; Fuerschbach, Kyle; Schmid, Tobias; Rolland, Jannick P.

    2009-08-01

    The alignment of three mirror anastigmatic (TMA) telescopes has been studied since their invention in the 60s. Recently, Thompson et al.1 reported that other than the conventional uniform coma over the field caused by misalignment, TMA telescopes display only one other misalignment induced aberration, field-asymmetric, field-linear astigmatism. Currently, an instrument with three TMAs is under development as the primary spectrometer on the James Webb Space Telescope. This paper will report on the application of Nodal Aberration Theory (NAT) to understanding the optical design of an optical system with multiple TMAs as a first step towards investigating and potentially independently analyzing the sensitivities to alignment of this key instrument.

  11. Amygdala-prefrontal pathways and the dopamine system affect nociceptive responses in the prefrontal cortex

    Onozawa Kitaro

    2011-11-01

    Full Text Available Abstract Background We previously demonstrated nociceptive discharges to be evoked by mechanical noxious stimulation in the prefrontal cortex (PFC. The nociceptive responses recorded in the PFC are conceivably involved in the affective rather than the sensory-discriminative dimension of pain. The PFC receives dense projection from the limbic system. Monosynaptic projections from the basolateral nucleus of the amygdala (BLA to the PFC are known to produce long-lasting synaptic plasticity. We examined effects of high frequency stimulation (HFS delivered to the BLA on nociceptive responses in the rat PFC. Results HFS induced long lasting suppression (LLS of the specific high threshold responses of nociceptive neurons in the PFC. Microinjection of N-methyl-D-aspartic acid (NMDA receptor antagonists (2-amino-5-phosphonovaleric acid (APV, dizocilpine (MK-801 and also metabotropic glutamate receptor (mGluR group antagonists (α-methyl-4-carboxyphenylglycine (MCPG, and 2-[(1S,2S-2-carboxycyclopropyl]-3-(9H-xanthen-9-yl-D-alanine (LY341495, prevented the induction of LLS of nociceptive responses. We also examined modulatory effects of dopamine (DA on the LLS of nociceptive responses. With depletion of DA in response to 6-hydroxydopamine (6-OHDA injection into the ipsilateral forebrain bundle, LLS of nociceptive responses was decreased, while nociceptive responses were normally evoked. Antagonists of DA receptor subtypes D2 (sulpiride and D4 (3-{[4-(4-chlorophenyl piperazin-1-yl] methyl}-1H-pyrrolo [2, 3-b] pyridine (L-745,870, microinjected into the PFC, inhibited LLS of nociceptive responses. Conclusions Our results indicate that BLA-PFC pathways inhibited PFC nociceptive cell activities and that the DA system modifies the BLA-PFC regulatory function.

  12. Expressions for third-order aberration theory for holographic images

    S K Tripathy; S Ananda Rao

    2003-01-01

    Expressions for third-order aberration in the reconstructed wave front of point objects are established by Meier. But Smith, Neil Mohon, Sweatt independently reported that their results differ from that of Meier. We found that coefficients for spherical aberration, astigmatism, tally with Meier’s while coefficients for distortion and coma differ.

  13. Fifth-order aberrations in magnetic quadrupole-octupole systems

    Explicit integral expressions are given for the fifth-order geometrical aberration coefficients in rectilinear magnetic quadrupole-octupole systems used for the transport of nonrelativistic charged particle beams. The numerical values of the fifth-order geometrical aberration coefficients for a rare earth cobalt (REC) quadrupole doublet are given as an example. 26 refs., 5 figs., 4 tabs

  14. Aberration analysis calculations for synchrotron radiation beamline design

    The application of ray deviation calculations based on aberration coefficients for a single optical surface for the design of beamline optical systems is reviewed. A systematic development is presented which allows insight into which aberration may be causing the rays to deviate from perfect focus. A new development allowing analytical calculation of line shape is presented

  15. Statistical virtual eye model based on wavefront aberration

    Wang, Jie-Mei; Liu, Chun-Ling; Luo, Yi-Ning; Liu, Yi-Guang; Hu, Bing-Jie

    2012-01-01

    Wavefront aberration affects the quality of retinal image directly. This paper reviews the representation and reconstruction of wavefront aberration, as well as the construction of virtual eye model based on Zernike polynomial coefficients. In addition, the promising prospect of virtual eye model is emphasized.

  16. Exact solutions in the scalar diffraction theory of aberrations.

    Budgor, A B

    1980-05-15

    A simple exact method is presented for evaluating the circularly symmetric Fresnel-Kirchhoff diffraction integral in the presence of Seidel aberrations, all orders of spherical aberration, and all orders of linear coma. The resultant formulas involve a simple quadrature over a single special function of mathematics. PMID:20221084

  17. Exact solutions in the scalar diffraction theory of aberrations

    A simple exact method is presented for evaluating the circularly symmetric Fresnel-Kirchhoff diffraction integral in the presence of Seidel aberrations, all orders of spherical aberration, and all orders of linear coma. The resultant formulas involve a simple quadrature over a single special function of mathematics

  18. Brown's transport up to third order aberration by artificial intelligence

    Brown's TRANSPORT is a first and second order matrix multiplication computer program intended for the design of accelerator beam transport systems, neglecting the third order aberration. Recently a new method was developed to derive analytically any order aberration coefficients of general charged particle optic system, applicable to any practical systems, such as accelerators, electron microscopes, lithographs, including those unknown systems yet to be invented. An artificial intelligence program in Turbo Prolog was implemented on IBM-PC 286 or 386 machine to generate automatically the analytical expression of any order aberration coefficients of general charged particle optic system. Based on this new method and technique, Brown's TRANSPORT is extended beyond the second order aberration effect by artificial intelligence, outputting automatically all the analytical expressions up to the third order aberration coefficients

  19. Chromosome aberration analysis based on a beta-binomial distribution

    Analyses carried out here generalized on earlier studies of chromosomal aberrations in the populations of Hiroshima and Nagasaki, by allowing extra-binomial variation in aberrant cell counts corresponding to within-subject correlations in cell aberrations. Strong within-subject correlations were detected with corresponding standard errors for the average number of aberrant cells that were often substantially larger than was previously assumed. The extra-binomial variation is accomodated in the analysis in the present report, as described in the section on dose-response models, by using a beta-binomial (B-B) variance structure. It is emphasized that we have generally satisfactory agreement between the observed and the B-B fitted frequencies by city-dose category. The chromosomal aberration data considered here are not extensive enough to allow a precise discrimination between competing dose-response models. A quadratic gamma ray and linear neutron model, however, most closely fits the chromosome data. (author)

  20. Brown's TRANSPORT up to third order aberration by artificial intelligence

    Brown's TRANSPORT is a first and second order matrix multiplication computer program intended for the design of accelerator beam transport systems, neglecting the third order aberration. Recently a new method was developed to derive analytically any order aberration coefficients of general charged particle optic system, applicable to any practical systems, such as accelerators, electron microscopes, lithographs, etc., including those unknown systems yet to be invented. An artificial intelligence program in Turbo Prolog was implemented on IBM-PC 286 or 386 machine to generate automatically the analytical expression of any order aberration coefficients of general charged particle optic system. Based on this new method and technique, Brown's TRANSPORT is extended beyond the second order aberration effects by artificial intelligence, outputing automatically all the analytical expressions up to the third order aberration coefficients

  1. Aberrations of the cathode objective lens up to fifth order.

    Tromp, R M; Wan, W; Schramm, S M

    2012-08-01

    In this paper we discuss a topic that was close to Prof. Gertrude Rempfer s interests for many years. On this occasion of her 100th birthday, we remember and honor Gertrude for her many outstanding contributions, and for the inspiring example that she set. We derive theoretical expressions for the aberration coefficients of the uniform electrostatic field up to 5th order and compare these with raytracing calculations for the cathode lens used in Low Energy Electron Microscopy and Photo Electron Emission Microscopy experiments. These higher order aberration coefficients are of interest for aberration corrected experiments in which chromatic (C(c)) and spherical (C₃) aberrations of the microscope are set to zero. The theoretical predictions are in good agreement with the results of raytracing. Calculations of image resolution using the Contrast Transfer Function method show that sub-nanometer resolution is achievable in an aberration corrected LEEM system. PMID:22188906

  2. Prefrontal korteks asimetrisinin kantitatif EEG ile Değerlendirilmesi

    ÇİÇEK, Metehan

    1998-01-01

      İman bilişiminde önemli role sahip olan prefrontal korteksin işlevleri henüz tam olarak aydınktılamamıştır. Posterior kortikal alanların asimetrik aktivasyonu hakkında daha çok bilgimiz olmasına rağmen anterior kortikal alanların asimetrik işlevleri araştırmaya açıktır. Özellikle prefrontal korteksin işleyen bellek işlevi sırasındaki asimetrik aktivasyonuna el tercihi ve cinsiyetin etkisi açıklık kazanmamıştır. Araştırmada EEG alfa asimetrisi kullanılarak, pref...

  3. Higher Order Spike Synchrony in Prefrontal Cortex during visual memory

    Gordon ePipa

    2011-06-01

    Full Text Available Precise temporal synchrony of spike firing has been postulated as an important neuronal mechanism for signal integration and the induction of plasticity in neocortex. As prefrontal cortex plays an important role in organizing memory and executive functions, the convergence of multiple visual pathways onto PFC predicts that neurons should preferentially synchronize their spiking when stimulus information is processed. Furthermore, synchronous spike firing should intensify if memory processes require the induction of neuronal plasticity, even if this is only for short-term. Here we show with multiple simultaneously recorded units in ventral prefrontal cortex that neurons participate in 3 ms precise synchronous discharges distributed across multiple sites separated by at least 500 µm. The frequency of synchronous firing is modulated by behavioral performance and is specific for the memorized visual stimuli. In particular, during the memory period in which activity is not stimulus driven, larger groups of up to 7 sites exhibit performance dependent modulation of their spike synchronization.

  4. Prefrontal activity predicts monkeys' decisions during an auditory category task

    Jung Hoon Lee

    2009-06-01

    Full Text Available The neural correlates that relate auditory categorization to aspects of goal-directed behavior, such as decision-making, are not well understood. Since the prefrontal cortex plays an important role in executive function and the categorization of auditory objects, we hypothesized that neural activity in the prefrontal cortex (PFC should predict an animal's behavioral reports (decisions during a category task. To test this hypothesis, we tested PFC activity that was recorded while monkeys categorized human spoken words (Russ et al., 2008b. We found that activity in the ventrolateral PFC, on average, correlated best with the monkeys' choices than with the auditory stimuli. This finding demonstrates a direct link between PFC activity and behavioral choices during a non-spatial auditory task.

  5. Social interaction with a cagemate in pain facilitates subsequent spinal nociception via activation of the medial prefrontal cortex in rats.

    Li, Zhen; Lu, Yun-Fei; Li, Chun-Li; Wang, Yan; Sun, Wei; He, Ting; Chen, Xue-Feng; Wang, Xiao-Liang; Chen, Jun

    2014-07-01

    Empathy for the pain experience of others can lead to the activation of pain-related brain areas and can even induce aberrant responses to pain in human observers. Recent evidence shows this high-level emotional and cognitive process also exists in lower animals; however, the mechanisms underlying this phenomenon remain unknown. In the present study we found that, after social interaction with a rat that had received subcutaneous injection of bee venom (BV), only the cagemate observer (CO) but not the noncagemate observer (NCO) showed bilateral mechanical hypersensitivity and an enhanced paw flinch reflex following BV injection. Moreover, neuronal activities labeled by c-Fos immunoreactivity in the spinal dorsal horn of CO rats were also significantly increased relative to the control 1 hour after BV injection. A stress-related response can be excluded because serum corticosterone concentration following social interaction with demonstrator rats in pain was not changed in CO rats relative to NCO and isolated control rats. Anxiety can also be excluded because anxiety-like behaviors could be seen in both the CO and NCO rats tested in the open-field test. Finally, bilateral lesions of the medial prefrontal cortex eliminated the enhancement of the BV-induced paw flinch reflex in CO rats, but bilateral lesions of either the amygdala or the entorhinal cortex failed. Together, we have provided another line of evidence for the existence of familiarity-dependent empathy for pain in rats and have demonstrated that the medial prefrontal cortex plays a critical role in processing the empathy-related enhancement of spinal nociception. PMID:24699208

  6. Shaping Memory Accuracy by Left Prefrontal Transcranial Direct Current Stimulation

    Zwissler, Bastian; Sperber, Christoph; Aigeldinger, Sina; Schindler, Sebastian; Kißler, Johanna; Plewnia, Christian

    2014-01-01

    Human memory is dynamic and flexible but is also susceptible to distortions arising from adaptive as well as pathological processes. Both accurate and false memory formation require executive control that is critically mediated by the left prefrontal cortex (PFC). Transcranial direct current stimulation (tDCS) enables noninvasive modulation of cortical activity and associated behavior. The present study reports that tDCS applied to the left dorsolateral PFC (dlPFC) shaped accuracy of episodic...

  7. Theta synchronizes the activity of medial prefrontal neurons during learning

    Paz, Rony; Bauer, Elizabeth P.; Paré, Denis

    2008-01-01

    Memory consolidation is thought to involve the gradual transfer of transient hippocampal-dependent traces to distributed neocortical sites via the rhinal cortices. Recently, medial prefrontal (mPFC) neurons were shown to facilitate this process when their activity becomes synchronized. However, the mechanisms underlying this enhanced synchrony remain unclear. Because the hippocampus projects to the mPFC, we tested whether theta oscillations contribute to synchronize mPFC neurons during learni...

  8. Cognitive Control, Goal Maintenance, and Prefrontal Function in Healthy Aging

    Paxton, Jessica L.; Barch, Deanna M; Racine, Caroline A; Braver, Todd S.

    2007-01-01

    Cognitive control impairments in healthy older adults may partly reflect disturbances in the ability to actively maintain goal-relevant information, a function that depends on the engagement of lateral prefrontal cortex (PFC). In 2 functional magnetic resonance imaging studies, healthy young and older adults performed versions of a task in which contextual cues provide goal-relevant information used to bias processing of subsequent ambiguous probes. In Study 1, a blocked design and manipulati...

  9. Flexible neural mechanisms of cognitive control within human prefrontal cortex

    Braver, Todd S.; Paxton, Jessica L.; Locke, Hannah S.; Barch, Deanna M

    2009-01-01

    A major challenge in research on executive control is to reveal its functional decomposition into underlying neural mechanisms. A typical assumption is that this decomposition occurs solely through anatomically based dissociations. Here we tested an alternative hypothesis that different cognitive control processes may be implemented within the same brain regions, with fractionation and dissociation occurring on the basis of temporal dynamics. Regions within lateral prefrontal cortex (PFC) wer...

  10. Changes in prefrontal axons may disrupt the network in autism

    Zikopoulos, Basilis; Barbas, Helen

    2010-01-01

    Neural communication is disrupted in autism by unknown mechanisms. Here we examined whether in autism there are changes in axons, which are the conduit for neural communication. We investigated single axons and their ultrastructure in the white matter of post-mortem human brain tissue below the anterior cingulate cortex (ACC), orbitofrontal (OFC), and lateral (LPFC) prefrontal cortices, which are associated with attention, social interactions, and emotions and have been consistently implicate...

  11. Optogenetic stimulation of prefrontal glutamatergic neurons enhances recognition memory

    Benn, Abi; Barker, Gareth R. I.; Stuart, Sarah A; Roloff, Eva v. L.; Teschemacher, Anja G; Warburton, Clea; Robinson, Emma S. J.

    2016-01-01

    Finding effective cognitive enhancers is a major health challenge; however, modulating glutamatergic neurotransmission has the potential to enhance performance in recognition memory tasks. Previous studies using glutamate receptor antagonists have revealed that the medial prefrontal cortex (mPFC) plays a central role in associative recognition memory. The present study investigates short-term recognition memory using optogenetics to target glutamatergic neurons within the rodent mPFC specific...

  12. Influence of restoration adjustments on prefrontal blood flow

    Sasaguri, Kenichi; Otsuka, Takero; Tsunashima, Hiroyuki; Shimazaki, Tateshi; Kubo, Kin-Ya; Onozuka, Minoru

    2015-01-01

    Objective The aim of this study was to examine, after setting several restorations, the influence of adjusted occlusal interference during gum chewing on blood flow in the prefrontal area as determined using near-infrared spectroscopy. Material and methods The physiological rate was assessed using a visual analog scale (VAS) questionnaire. We selected 16 patients who desired prosthetic restorative treatment on the lateral dentition, and eight healthy volunteers. Subjects were divided into thr...

  13. Prefrontal Cortex, Emotion, and Approach/Withdrawal Motivation

    Spielberg, Jeffrey M; Stewart, Jennifer L.; Levin, Rebecca L.; Miller, Gregory A.; Heller, Wendy

    2008-01-01

    This article provides a selective review of the literature and current theories regarding the role of prefrontal cortex, along with some other critical brain regions, in emotion and motivation. Seemingly contradictory findings have often appeared in this literature. Research attempting to resolve these contradictions has been the basis of new areas of growth and has led to more sophisticated understandings of emotional and motivational processes as well as neural networks associated with thes...

  14. Prefrontal inputs to the amygdala instruct fear extinction memory formation

    Bukalo, Olena; Pinard, Courtney R.; Silverstein, Shana; Brehm, Christina; Hartley, Nolan D.; Whittle, Nigel; Colacicco, Giovanni; Busch, Erica; Patel, Sachin; Singewald, Nicolas; Holmes, Andrew

    2015-01-01

    Persistent anxiety after a psychological trauma is a hallmark of many anxiety disorders. However, the neural circuits mediating the extinction of traumatic fear memories remain incompletely understood. We show that selective, in vivo stimulation of the ventromedial prefrontal cortex (vmPFC)–amygdala pathway facilitated extinction memory formation, but not retrieval. Conversely, silencing the vmPFC-amygdala pathway impaired extinction formation and reduced extinction-induced amygdala activity....

  15. Is the Medial Prefrontal Cortex Necessary for Theory of Mind?

    Otti, Alexander; Wohlschläger, Afra; Noll-Hussong, Michael

    2015-01-01

    Background: Successful social interaction relies on the ability to attribute mental states to other people. Previous functional neuroimaging studies have shown that this process, described as Theory of Mind (ToM) or mentalization, is reliably associated with activation of the medial prefrontal cortex (mPFC). However, this study presents a novel and surprising finding that provides new insight into the role of the mPFC in mentalization tasks. Methodology/Principal Findings: Twenty ...

  16. Prefrontal Cortex in Learning to Overcome Generalized Fear

    Edward Korzus

    2015-01-01

    SUMMARY Normal brain functioning relies critically on the ability to control appropriate behavioral responses to fearful stimuli. Overgeneralized fear is the major symptom of anxiety disorders including posttraumatic stress disorder. This review describes recent data demonstrating that the medial prefrontal cortex (mPFC) plays a critical role in the refining of cues that drive the acquisition of fear response. Recent studies on molecular mechanisms that underlie the role of mPFC in fear discr...

  17. Behavioral Effects of Congenital Ventromedial Prefrontal Cortex Malformation

    Boes Aaron D; Grafft Amanda; Joshi Charuta; Chuang Nathaniel A; Nopoulos Peg; Anderson Steven W

    2011-01-01

    Abstract Background A detailed behavioral profile associated with focal congenital malformation of the ventromedial prefrontal cortex (vmPFC) has not been reported previously. Here we describe a 14 year-old boy, B.W., with neurological and psychiatric sequelae stemming from focal cortical malformation of the left vmPFC. Case Presentation B.W.'s behavior has been characterized through extensive review Patience of clinical and personal records along with behavioral and neuropsychological testin...

  18. Stress-induced prefrontal reorganization and executive dysfunction in rodents

    Holmes, Andrew; Wellman, Cara L.

    2008-01-01

    The prefrontal cortex (PFC) mediates a range of higher order ‘executive functions’ that subserve the selection and processing of information in such a way that behavior can be planned, controlled and directed according to shifting environmental demands. Impairment of executive functions typifies many forms of psychopathology, including schizophrenia, mood and anxiety disorders and addiction, that are often associated with a history of trauma and stress. Recent research in animal models demons...

  19. Brain injury impairs working memory and prefrontal circuit function

    Colin James Smith

    2015-11-01

    Full Text Available More than 2.5 million Americans suffer a traumatic brain injury (TBI each year. Even mild to moderate traumatic brain injury causes long-lasting neurological effects. Despite its prevalence, no therapy currently exists to treat the underlying cause of cognitive impairment suffered by TBI patients. Following lateral fluid percussion injury (LFPI, the most widely used experimental model of TBI, we investigated alterations in working memory and excitatory/inhibitory synaptic balance in the prefrontal cortex. LFPI impaired working memory as assessed with a T-maze behavioral task. Field excitatory postsynaptic potentials recorded in the prefrontal cortex were reduced in slices derived from brain-injured mice. Spontaneous and miniature excitatory postsynaptic currents onto layer 2/3 neurons were more frequent in slices derived from LFPI mice while inhibitory currents onto layer 2/3 neurons were smaller after LFPI. Additionally, an increase in action potential threshold and concomitant decrease in firing rate was observed in layer 2/3 neurons in slices from injured animals. Conversely, no differences in excitatory or inhibitory synaptic transmission onto layer 5 neurons were observed; however, layer 5 neurons demonstrated a decrease in input resistance and action potential duration after LFPI. These results demonstrate synaptic and intrinsic alterations in prefrontal circuitry that may underlie working memory impairment caused by TBI.

  20. Probing prefrontal function in schizophrenia with neuropsychological paradigms.

    Goldberg, T E; Weinberger, D R

    1988-01-01

    In a recent series of studies we have attempted to clarify the nature of intellectual impairment in schizophrenia, and in particular, how patterns of dysfunction implicate specific neural systems. First, we found that acute psychotic adolescent patients displayed the same pattern of IQ scores (Performance less than Verbal) as adult chronic schizophrenic patients. We explored this deficit in problem solving by studying the performance of schizophrenic patients after receiving concrete and explicit instructions on how to do the Wisconsin Card Sorting Test, a task thought to be mediated by prefrontal cortex. We then studied the differential impact such a deficit in problem-solving strategies might have on a task thought to elicit both cognitive (prefrontal) and procedural or motor-skill (basal ganglia) processing. Procedural components appeared to be relatively more intact. We also addressed schizophrenic patients' ability to learn in other (extrafrontal) cognitive domains through verbal memory tasks and block design puzzles. Learning occurred under both conditions. We believe the overall pattern of deficit implicates primarily prefrontal neural systems, though a number of other neuropsychological functions are yet to be surveyed. PMID:3059467

  1. Networks of power in digital copyright law and policy political salience, expertise and the legislative process

    Farrand, Benjamin

    2014-01-01

    In this book, Benjamin Farrand employs an interdisciplinary approach that combines legal analysis with political theory to explore the development of copyright law in the EU. Farrand utilises Foucault's concept of Networks of Power and Culpepper's Quiet Politics to assess the adoption and enforcement of copyright law in the EU, including the role of industry representative, cross-border licensing, and judicial approaches to territorial restrictions. Focusing in particular on legislative initiatives concerning copyright, digital music and the internet, Networks of Power in Digital Copyright Law and Policy: Political Salience, Expertise and the Legislative Process demonstrates the connection between copyright law and complex network relationships. This book presents an original socio-political theoretical framework for assessing developments in copyright law that will interest researchers and post-graduate students of law and politics, as well as those more particularly concerned with political theory, EU and c...

  2. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience

    Diankun Gong

    2016-01-01

    Full Text Available Action video games (AVGs have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN and Central Executive Network (CEN, which are responsible for attention and working memory, respectively, two cognitive functions essential for AVG playing. This study initiated a systematic investigation of this proposition by analyzing AVG experts’ and amateurs’ resting-state brain functions through graph theoretical analyses and functional connectivity. Results reveal enhanced intra- and internetwork functional integrations in AVG experts compared to amateurs. The findings support the possible relation between AVG experience and the neural network plasticity.

  3. ERP correlates of involuntary attention capture by prosodic salience in speech.

    Wang, Jingtian; Friedman, David; Ritter, Walter; Bersick, Michael

    2005-01-01

    This study addressed whether temporally salient (e.g., word onset) or prosodically salient (e.g., stressed syllables) information serves as a cue to capture attention in speech sound analysis. In an auditory oddball paradigm, 16 native English speakers were asked to ignore binaurally presented disyllabic speech sounds and watch a silent movie while ERPs were recorded. Four types of phonetic deviants were employed: a deviant syllable that was either stressed or unstressed and that occurred in either the first or second temporal position. The nature of the phonetic change (a change from a voiced consonant to its corresponding unvoiced consonant) was kept constant. MMNs were observed for all deviants. In contrast, the P3a was only seen when the deviance occurred on stressed syllables. The sensitivity of the P3a to the stress manipulation suggests that prosodic rather than temporal salience captures attention in unattended speech sounds. PMID:15720580

  4. Altruism During Ebola: Risk Perception, Issue Salience, Cultural Cognition, and Information Processing.

    Yang, Z Janet

    2016-06-01

    A nationally representative sample of 1,046 U.S. adults was randomly assigned to two experimental conditions that triggered different degrees of risk perception related to the Ebola outbreak. In the high-risk condition, issue salience and deliberate processing increased individuals' altruistic behavioral intention. In contrast, cultural cognition worldview and negative emotions such as sadness and anger were significantly related to altruistic behavioral intention regardless of the experimental conditions. These findings suggest that affective responses diverge from cognitive processes in influencing risk-related decisions. Practically, as the United States continues to send experts to the affected countries in West Africa, results from this study suggest meaningful pathways to improve risk communication intended to encourage more altruistic and pro-social behaviors. PMID:26660724

  5. A No-Reference Texture Regularity Metric Based on Visual Saliency.

    Varadarajan, Srenivas; Karam, Lina J

    2015-09-01

    This paper presents a no-reference perceptual metric that quantifies the degree of perceived regularity in textures. The metric is based on the similarity of visual attention (VA) of the textural primitives and the periodic spatial distribution of foveated fixation regions throughout the image. A ground-truth eye-tracking database for textures is also generated as part of this paper and is used to evaluate the performance of the most popular VA models. Using the saliency map generated by the best VA model, the proposed texture regularity metric is computed. It is shown through subjective testing that the proposed metric has a strong correlation with the mean opinion score for the perceived regularity of textures. The proposed texture regularity metric can be used to improve the quality and performance of many image processing applications like texture synthesis, texture compression, and content-based image retrieval. PMID:25826803

  6. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience.

    Gong, Diankun; He, Hui; Ma, Weiyi; Liu, Dongbo; Huang, Mengting; Dong, Li; Gong, Jinnan; Li, Jianfu; Luo, Cheng; Yao, Dezhong

    2016-01-01

    Action video games (AVGs) have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN) and Central Executive Network (CEN), which are responsible for attention and working memory, respectively, two cognitive functions essential for AVG playing. This study initiated a systematic investigation of this proposition by analyzing AVG experts' and amateurs' resting-state brain functions through graph theoretical analyses and functional connectivity. Results reveal enhanced intra- and internetwork functional integrations in AVG experts compared to amateurs. The findings support the possible relation between AVG experience and the neural network plasticity. PMID:26885408

  7. Disentangling the influence of salience and familiarity on infant word learning: methodological advances.

    Bortfeld, Heather; Shaw, Katie; Depowski, Nicole

    2013-01-01

    The initial stages of language learning involve a critical interaction between infants' environmental experience and their developing brains. The past several decades of research have produced important behavioral evidence of the many factors influencing this process, both on the part of the child and on the part of the environment that the child is in. The application of neurophysiological techniques to the study of early development has been augmenting these findings at a rapid pace. While the result is an accrual of data bridging the gap between brain and behavior, much work remains to make the link between behavioral evidence of infants' emerging sensitivities and neurophysiological evidence of changes in how their brains process information. Here we review the background behavioral data on how salience and familiarity in the auditory signal shape initial language learning. We follow this with a summary of more recent evidence of changes in infants' brain activity in response to specific aspects of speech. Our goal is to examine language learning through the lens of brain/environment interactions, ultimately focusing on changes in cortical processing of speech across the first year of life. We will ground our examination of recent brain data in the two auditory features initially outlined: salience and familiarity. Our own and others' findings on the influence of these two features reveal that they are key parameters in infants' emerging recognition of structure in the speech signal. Importantly, the evidence we review makes the critical link between behavioral and brain data. We discuss the importance of future work that makes this bridge as a means of moving the study of language development solidly into the domain of brain science. PMID:23616775

  8. Disentangling the Influence of Salience and Familiarity on Infant Word Learning: Methodological Advances

    Heather Bortfeld

    2013-04-01

    Full Text Available The initial stages of language learning involve a critical interaction between infants’ environmental experience and their developing brains. The past several decades of research have produced important behavioral evidence of the many factors influencing this process, both on the part of the child and on the part of the environment that the child is in. The application of neurophysiological techniques to the study of early development has been augmenting these findings at a rapid pace. While the result is an accrual of data bridging the gap between brain and behavior, much work remains to make the link between behavioral evidence of infants' emerging sensitivities and neurophysiological evidence of changes in how their brains process information. Here we review the background behavioral data on how salience and familiarity in the auditory signal shape initial language learning. We follow this with a summary of more recent evidence of changes in infants’ brain activity in response to specific aspects of speech. Our goal is to examine language learning through the lens of brain/environment interactions, ultimately focusing on changes in cortical processing of speech across the first year of life. We will ground our examination of recent brain data in the two auditory features initially outlined: salience and familiarity. Our own and others' findings on the influence of these two features reveal that they are key parameters in infants’ emerging recognition of structure in the speech signal. Importantly, the evidence we review makes the critical link between behavioral and brain data. We discuss the importance of future work that makes this bridge as a means of moving the study of language development solidly into the domain of brain science.

  9. Aberrations of the cathode objective lens up to fifth order

    Tromp, R.M., E-mail: rtromp@us.ibm.com [Thomas J. Watson Research Center, IBM Research Division, 1101 Kitchawan Road, P.O. Box 218, Yorktown Heights, NY 10598 (United States); Leiden University, Kamerlingh Onnes Laboratorium, P.O. Box 9504, NL-2300 RA Leiden (Netherlands); Wan, W. [Ernest Orlando Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 80R0114, Berkeley, CA 94720 (United States); Schramm, S.M. [Leiden University, Kamerlingh Onnes Laboratorium, P.O. Box 9504, NL-2300 RA Leiden (Netherlands)

    2012-08-15

    In this paper we discuss a topic that was close to Prof. Gertrude Rempfer s interests for many years. On this occasion of her 100th birthday, we remember and honor Gertrude for her many outstanding contributions, and for the inspiring example that she set. We derive theoretical expressions for the aberration coefficients of the uniform electrostatic field up to 5th order and compare these with raytracing calculations for the cathode lens used in Low Energy Electron Microscopy and Photo Electron Emission Microscopy experiments. These higher order aberration coefficients are of interest for aberration corrected experiments in which chromatic (C{sub c}) and spherical (C{sub 3}) aberrations of the microscope are set to zero. The theoretical predictions are in good agreement with the results of raytracing. Calculations of image resolution using the Contrast Transfer Function method show that sub-nanometer resolution is achievable in an aberration corrected LEEM system. -- Highlights: Black-Right-Pointing-Pointer A theory is presented for the aberrations of the uniform electrostatic field up to fifth order. Black-Right-Pointing-Pointer Such aberrations are important for advanced LEEM and PEEM instruments. Black-Right-Pointing-Pointer Good agreement between theory and raytracing results for a full cathode objective lens. Black-Right-Pointing-Pointer Contrast Transfer Function calculations predict that spatial resolution below 1 nm is achievable.

  10. Chromosome aberrations in solid tumors have a stochastic nature

    Castro, Mauro A.A. [Departamento de Bioquimica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-anexo, Porto Alegre 90035-003 (Brazil) and Departamento de Medicina Interna, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2350, Porto Alegre 90035-903 (Brazil) and Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Porto Alegre 91501-970 (Brazil) and Universidade Luterana do Brasil, Rua Miguel Tostes 101, Canoas 92420-280 (Brazil)]. E-mail: mauro@ufrgs.br; Onsten, Tor G.H. [Departamento de Medicina Interna, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2350, Porto Alegre 90035-903 (Brazil); Universidade Luterana do Brasil, Rua Miguel Tostes 101, Canoas 92420-280 (Brazil); Moreira, Jose C.F. [Departamento de Bioquimica, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos 2600-anexo, Porto Alegre 90035-003 (Brazil); Almeida, Rita M.C. de [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Av. Bento Goncalves 9500, Porto Alegre 91501-970 (Brazil)

    2006-08-30

    An important question nowadays is whether chromosome aberrations are random events or arise from an internal deterministic mechanism, which leads to the delicate task of quantifying the degree of randomness. For this purpose, we have defined several Shannon information functions to evaluate disorder inside a tumor and between tumors of the same kind. We have considered 79 different kinds of solid tumors with 30 or more karyotypes retrieved from the Mitelman Database of Chromosome Aberrations in Cancer. The Kaplan-Meier cumulative survival was also obtained for each solid tumor type in order to correlate data with tumor malignance. The results here show that aberration spread is specific for each tumor type, with high degree of diversity for those tumor types with worst survival indices. Those tumor types with preferential variants (e.g. high proportion of a given karyotype) have shown better survival statistics, indicating that aberration recurrence is a good prognosis. Indeed, global spread of both numerical and structural abnormalities demonstrates the stochastic nature of chromosome aberrations by setting a signature of randomness associated to the production of disorder. These results also indicate that tumor malignancy correlates not only with karyotypic diversity taken from different tumor types but also taken from single tumors. Therefore, by quantifying aberration spread, we could confront diverse models and verify which of them points to the most likely outcome. Our results suggest that the generating process of chromosome aberrations is neither deterministic nor totally random, but produces variations that are distributed between these two boundaries.

  11. Aberrant DNA methylation in cloned ovine embryos

    LIU Lei; HOU Jian; LEI TingHua; BAI JiaHua; GUAN Hong; AN XiaoRong

    2008-01-01

    By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine (5MeC), the present study detected the DNA methylation patterns of cloned ovine embryos. The em-bryos derived from in vitro fertilization were also examined for reference purpose. The results showed that: (1) during the pre-implantation development, cloned embryos displayed a similar demethylation profile to the fertilized embryos; that is, the methylation level decreased to the lowest at 8-cell stage, and then increased again at morulae stage. However, methylation level was obviously higher in cloned embryos than in stage-matched fertilized embryos, especially at 8-cell stage and afterwards; (2) at blastocyst stage, the methylation pattern in cloned embryos was different from that in fertilized em-bryos. In cloned blastocyst, inner cell mass (ICM) exhibited a comparable level to trophectoderm cells (TE), while in in-vitro fertilized blastocyst the methylation level of ICM was lower than that of TE, which is not consistent with that reported by other authors. These results indicate that DNA methylation is abnormally reprogrammed in cloned embryos, implying that aberrant DNA methylation reprogramming may be one of the factors causing cloned embryos developmental failure.

  12. Aberrant glycosylation associated with enzymes as cancer biomarkers

    Meany Danni L

    2011-06-01

    Full Text Available Abstract Background One of the new roles for enzymes in personalized medicine builds on a rational approach to cancer biomarker discovery using enzyme-associated aberrant glycosylation. A hallmark of cancer, aberrant glycosylation is associated with differential expressions of enzymes such as glycosyltransferase and glycosidases. The aberrant expressions of the enzymes in turn cause cancer cells to produce glycoproteins with specific cancer-associated aberrations in glycan structures. Content In this review we provide examples of cancer biomarker discovery using aberrant glycosylation in three areas. First, changes in glycosylation machinery such as glycosyltransferases/glycosidases could be used as cancer biomarkers. Second, most of the clinically useful cancer biomarkers are glycoproteins. Discovery of specific cancer-associated aberrations in glycan structures of these existing biomarkers could improve their cancer specificity, such as the discovery of AFP-L3, fucosylated glycoforms of AFP. Third, cancer-associated aberrations in glycan structures provide a compelling rationale for discovering new biomarkers using glycomic and glycoproteomic technologies. Summary As a hallmark of cancer, aberrant glycosylation allows for the rational design of biomarker discovery efforts. But more important, we need to translate these biomarkers from discovery to clinical diagnostics using good strategies, such as the lessons learned from translating the biomarkers discovered using proteomic technologies to OVA 1, the first FDA-cleared In Vitro Diagnostic Multivariate Index Assay (IVDMIA. These lessons, providing important guidance in current efforts in biomarker discovery and translation, are applicable to the discovery of aberrant glycosylation associated with enzymes as cancer biomarkers as well.

  13. Protein kinase C activity is associated with prefrontal cortical decline in aging

    Brennan, Avis R.; Yuan, Peixiong; Dickstein, Dara L; Rocher, Anne B.; Hof, Patrick R.; Manji, Husseini; Arnsten, Amy F.T.

    2007-01-01

    Aging is associated with deficiencies in the prefrontal cortex, including working memory impairment, and compromised integrity of neuronal dendrites. Although protein kinase C (PKC) is implicated in structural plasticity, and overactivation of PKC results in working memory impairments in young animals, the role of PKC in prefrontal cortical impairments in the aged has not been examined. This study provides the first evidence that PKC activity is associated with prefrontal cortical dysfunction...

  14. Guanfacine Modulates the Emotional Biasing of Amygdala-Prefrontal Connectivity for Cognitive Control

    Schulz, Kurt P.; Clerkin, Suzanne M.; Newcorn, Jeffrey H; Jeffrey M. Halperin; Fan, Jin

    2014-01-01

    Functional interactions between amygdala and prefrontal cortex provide a cortical entry point for emotional cues to bias cognitive control. Stimulation of α2 adrenoceptors enhances the prefrontal control functions and blocks the amygdala-dependent encoding of emotional cues. However, the impact of this stimulation on amygdala-prefrontal interactions and the emotional biasing of cognitive control have not been established. We tested the effect of the α2 adrenoceptor agonist guanfacine on psych...

  15. Cell-type Specific Development of NMDA Receptors in the Interneurons of Rat Prefrontal Cortex

    Wang, Huai-Xing; Gao, Wen-Jun

    2009-01-01

    In the prefrontal cortex, N-methyl-D-aspartic acid (NMDA) receptors are critical not only for normal prefrontal functions but also for the pathological processes of schizophrenia. Little is known, however, about the developmental properties of NMDA receptors in the functionally diverse subpopulations of interneurons. We investigated the developmental changes of NMDA receptors in rat prefrontal interneurons using patch clamp recording in cortical slices. We found that fast-spiking (FS) interne...

  16. Sex Differences in COMT Polymorphism Effects on Prefrontal Inhibitory Control in Adolescence

    BOKDE, ARUN

    2014-01-01

    Catecholamine-0-methyl-transferase (COMT) gene variation effects on prefrontal blood oxygenation-level-dependent (BOLD) activation are robust; however, despite observations that COMT is estrogenically catabolized, sex differences in its prefrontal repercussions remain unclear. Here, in a large sample of healthy adolescents stratified by sex and Val(158)Met genotype (n=1133), we examine BOLD responses during performance of the stop-signal task in right-hemispheric prefrontal regions fundamenta...

  17. Differential algebraic method for aberration analysis of typical electrostatic lenses

    In this paper up to fifth-order geometric and third-order chromatic aberration coefficients of typical electrostatic lenses are calculated by means of the charged particle optics code, COSY INFINITY, based on the differential algebraic (DA) method. A two-tube immersion lens and a symmetric einzel lens have been chosen as two examples, whose axial potential distributions are numerically calculated by a FORTRAN program using the finite difference method. The DA results are in good agreement with those evaluated by the aberration integrals in electron optics. The DA method presented here can easily be extended to aberration analysis of other numerically computed electron lenses, including magnetic lenses

  18. Aberrations of Genetic Material as Biomarkers of Ionizing Radiation Effects

    Milacic, S.

    2004-07-01

    Ionizing radiation is the most powerful mutagen in environmental and working conditions. The result of genotoxic effect of radiation is the development of chromosome aberrations. The structural chromosome aberrations in peripheral blood lymphocytes are dicentric, ring, acentric fragment. The observation of chromosome aberration frequency in lymphocyte karyotype is the conclusive method to assess the absorbed dose of ionizing radiation. Our study compared the incidence of chromosome aberrations in occupationally exposed healthy medical workers and in non-exposed healthy population. We analyzed the effect of working place, dose by thermo luminescence personal dosimeter (TLD), duration of occupational exposure (DOE) and age to the sum of aberrant cells and aberrations. four-year study included 462 subjects, mean-aged 42.3 years, who were occupational exposed to ionizing radiation and 95 subjects, mean-aged 35,2 years, who were not exposed to ionizing radiation, during the same time period and from the same territory. All of them possess thermo luminescence personal dosimeter (TLD) which is read by scanner for thermo luminescence dosimeters. Modified Moorheard's micro method for peripheral blood lymphocytes and conventional cytogenetic technique of chromosome aberration analysis were used for analysis of chromosome aberrations. Stained preparations (Giemsa) are observed in immersion by light microscope. The karyotype of 200 lymphocytes in metaphase is analyzed the most characteristic aberration: dicentric, then the ring and acentric fragments. The increased incidence of chromosome aberrations was found to tbe 21.6% in the exposed group and 2.1% in the controls, while the findings within the limits (non-specific chromosome lesions-gaps breaks, elongations, and exchanges) were equal in both groups (22%). Among occupationally exposed medical workers, the highest incidence was found in nuclear medicine workers (42.6%), then in orthopedists (27.08%). There is highly

  19. High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric,aberration correcting monofocal intraocular lens

    Florian; T; A; Kretz; Tamer; Tandogan; Ramin; Khoramnia; Gerd; U; Auffarth

    2015-01-01

    ·AIM: To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting,monofocal intraocular lens(IOL).·METHODS: Twenty-one patients(34 eyes) aged 50 to83 y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL(Tecnis ZCB00,Abbott Medical Optics). Three months after surgery they were examined for uncorrected(UDVA) and corrected distance visual acuity(CDVA), contrast sensitivity(CS)under photopic and mesopic conditions with and without glare source, ocular high order aberrations(HOA, Zywave II) and retinal straylight(C-Quant).· RESULTS: Postoperatively, patients achieved a postoperative CDVA of 0.0 log MAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27(primary coma components) and-0.04 ±0.16(spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed(P ≥0.28).· CONCLUSION: The implantation of an aspherical aberration correcting monofocal IOL after cataractsurgery resulted in very low residual higher order aberration(HOA) and normal straylight.

  20. Chromosome aberrations in pesticide-exposed greenhouse workers

    Lander, B F; Knudsen, Lisbeth E.; Gamborg, M O;

    2000-01-01

    OBJECTIVES: The aim of this study was to investigate the possibility of subtoxic exposure to pesticides causing chromosome aberrations in greenhouse workers. METHODS: In a cross-sectional and prospective study design chromosome aberration frequencies in cultured lymphocytes were examined for 116...... greenhouse workers exposed to a complex mixture of almost 50 insecticides, fungicides, and growth regulators and also for 29 nonsmoking, nonpesticide-exposed referents. RESULTS: The preseason frequencies of chromosome aberrations were slightly but not statistically significantly elevated for the greenhouse...... workers when they were compared with the referents. After a summer season of pesticide spraying in the greenhouses, the total frequencies of cells with chromosome aberrations were significantly higher than in the preseason samples (P=0.02) and also higher than for the referents (P=0.05). This finding was...

  1. Electron Optics for Biologists: Physical Origins of Spherical Aberrations

    Geissler, Peter; Zadunaisky, Jose

    1974-01-01

    Reports on the physical origins of spherical aberrations in axially symmetric electrostatic lenses to convey the essentials of electon optics to those who must think critically about the resolution of the electron microscope. (GS)

  2. CT of ruptured aneurysm of aberrant right subclavian artery.

    Vega, A; Ortíz, A; Longo, J M; Pagola, M A

    1987-01-01

    This paper presents the first description of a ruptured aneurysm of an aberrant right subclavian artery. CT clearly demonstrated the vascular malformation as well as the existence of a bilateral hemothorax. PMID:3102065

  3. Lymphocyte chromosome aberrations in partial-body fractionated radiation therapy

    a relationship between lymphocyte chromosome aberration yields which occur in partial-body fractionated radiation therapy and those yields measured in vitro is derived. These calculations are applied to the case of patients undergoing radiation therapy for mammary carcinoma. (author)

  4. Lymphocyte chromosome aberrations in partial-body fractionated radiation therapy

    Ekstrand, K.E.; Dixon, R.L. (Wake Forest Univ., Winston-Salem, NC (USA))

    1982-03-01

    a relationship between lymphocyte chromosome aberration yields which occur in partial-body fractionated radiation therapy and those yields measured in vitro is derived. These calculations are applied to the case of patients undergoing radiation therapy for mammary carcinoma.

  5. Lens aberration measurement and analysis using a novel pattern

    Nam, Byung-Ho; Cho, Byeong-Ho; Park, Jong O.; Kim, Dong-Seok; Baek, SungJin; Jeong, JongHo; Nam, ByungSub; Hwang, Young J.; Song, Young Jin

    2001-09-01

    Lens aberration of the exposure tool causes pattern deformation and position shift. As design rule shrinks, the ratio of printed feature size to applied wavelength for optical lithography is driven inexorably toward resolution limit. In this study, we devised an efficient method to evaluate lens aberration using multi-ring pattern on an attenuated phase-shift mask. Adoption of multi-ring pattern can cut down measurement time and improve measurement repeatability. These patterns are uniformly distributed through entire field in 7 by 7 manner. Lens aberration was evaluated by multi-ring pattern array under conventional or off-axis illumination with KrF stepper of NA 0.65. Multi-ring critical dimension (CD) data was discussed together with the issue of lens aberration such as coma, astigmatism, field curvature, etc. We can apply this new measurement technique to select better lens system efficiently. multi-ring, field size, pattern deformation

  6. Optimizing chromatic aberration calibration using a novel genetic algorithm

    Fang, Yi-Chin; Liu, Tung-Kuan; MacDonald, John; Chou, Jyh-Horng; Wu, Bo-Wen; Tsai, Hsien-Lin; Chang, En-Hao

    2006-10-01

    Advances in digitalized image optics has increased the importance of chromatic aberration. The axial and lateral chromatic aberrations of an optical lens depends on the choice of optical glass. Based on statistics from glass companies worldwide, more than 300 optical glasses have been developed for commercial purposes. However, the complexity of optical systems makes it extremely difficult to obtain the right solution to eliminate small chromatic aberration. Even the damped least-squares technique, which is a ray-tracing-based method, is limited owing to its inability to identify an enhanced optical system configuration. Alternatively, this study instead attempts to eliminate even negligible axial and lateral colour aberration by using algorithms involving the theories of geometric optics in triplet lens, binary and real encoding, multiple dynamic crossover and random gene mutation techniques.

  7. Aberrant internal carotid artery in the middle ear

    The knowledge about the aberrant internal carotid artery (ICA) in the middle ear is essential for clinicians, because a misdiagnosis of the aberrant ICA could have serious consequences such as excessive aural bleeding during a middle ear surgery. A 38-year-old woman presented with tinnitus and hearing difficulties of the left ear that had started 5 years ago. During otoscopy, an anteroinferior bluish mass was seen in the tympanic space. Computed tomography and magnetic resonance imaging demonstrated a left-side aberrant ICA with bony dehiscence of the carotid canal in the middle ear and a reduced diameter of the tympanic ICA. Herein we report a case of an aberrant ICA in the middle ear. We also review the literature regarding this important vascular anomaly of the temporal bone which may lead to disastrous surgical complications.

  8. Aberrant internal carotid artery in the middle ear

    Roh, Keun Tak; Kang, Hyun Koo [Dept. of Radiology, Seoul Veterans Hospital, Seoul (Korea, Republic of)

    2014-10-15

    The knowledge about the aberrant internal carotid artery (ICA) in the middle ear is essential for clinicians, because a misdiagnosis of the aberrant ICA could have serious consequences such as excessive aural bleeding during a middle ear surgery. A 38-year-old woman presented with tinnitus and hearing difficulties of the left ear that had started 5 years ago. During otoscopy, an anteroinferior bluish mass was seen in the tympanic space. Computed tomography and magnetic resonance imaging demonstrated a left-side aberrant ICA with bony dehiscence of the carotid canal in the middle ear and a reduced diameter of the tympanic ICA. Herein we report a case of an aberrant ICA in the middle ear. We also review the literature regarding this important vascular anomaly of the temporal bone which may lead to disastrous surgical complications.

  9. Isoplanatic patch size for aberration correction in ultrasonic imaging

    Pilkington, Wayne C.

    Methods and experimental results are described for determination of the region size in an aberrating medium over which a single set of aberration estimates can achieve satisfactory b-scan resolution ( i.e., the isoplanatic patch) using time-shift compensation for aberration correction of ultrasonic transmit and receive beams. Based on twenty percent allowable increases in the -12 dB width of the receive or transmit beam focus using cross-correction compared to self-correction, the isoplanatic patch sizes were found to between 3 and 5 millimeters laterally for a linearly-scanned transducer, and at least 12 millimeters axially for a target distance of 55 millimeters and aberration comparable to human abdominal wall. These sizes depend on the aberration severity, reference site axial position, and allowable resolution degradation with cross-correction. The lateral isoplanatic patch size of a linearly scanned image can be more than doubled to match that of a beam-steered acquisition using aberration estimate position matching relative to the tissue surface. Further expansion of the lateral isoplanatic patch size by an additional 50 to 100 percent for both scanning methods is also shown through propagation path matched cross-correction mapping of aberration estimates. The specific mapping required to achieve the best propagation path match depends on the axial distribution of the aberrating structures, the focal depth being imaged, and the cross-correction distance. The effectiveness of alternate methods to derive propagation path matching maps with and without a priori knowledge of aberrator spatial distribution are contrasted; and a means to dynamically adjust correction maps to maximize isoplanatic patch sizes is proposed and verified. Lateral cross-correction mapping and the map changes required for each cross-correction distance can all be implemented with simple shifting of aberration estimates within the transducer aperture. Therefore, use of optimally mapped

  10. Cocaine mummies and the pre-frontal reality

    Full text: The scientific community frames its world with facts - facts which have been subjected to tests and apparently proven themselves and are therefore proffered by scientists to mankind as things upon which it can rely to steer it safely through life. However, facts are a moveable feast. Time and fresh minds often prove scientific 'facts' wrong. The cocaine mummies seem to indicate that 2000 years ago the Ancient Egyptians had access to both tobacco and cocaine - something previously believed impossible. One part of the German and British scientific community has proven in laboratory tests that the mummies are telling the truth. The rest of the scientific community disputes that truth'. But if the laboratory tests are right, then humanity has to rewrite its entire history. Nuclear communicators have very little credibility with the general public because they represent scientists, who not only are often proven wrong by time but also cannot agree on the truth. At the same time, there are fundamental facts about the human condition that nuclear communicators ignore - to the detriment of their message. Fact: thinking is a learned skill, not an instinct. Fact: language is a learned skill, not an instinct. For humans to follow the positive nuclear argument they must both think and also understand language. But thinking is not the brain's first choice of operation. Fact: the pre-frontal lobe of the brain is the seat of mankind's primitive emotions, including the instinct of fear and the instinct for life. The pre-frontal lobe dominates the way man thinks and speaks. Therefore, nuclear communicators have to learn the skill of mapping their messages to the pre-frontal human reality. This presentation provides practical points for that learning and message mapping exercise. (author)

  11. Moment aberrations in magneto-electrostatic plasma lenses (computer simulation)

    Butenko, V I

    2001-01-01

    In this work moment aberrations in the plasma magneto-electrostatic lenses are considered in more detail with the use of the computer modeling. For solution of the problem we have developed a special computer code - the model of plasma optical focusing device, allowing to display the main parameters and operations of experimental sample of a lens, to simulate the moment and geometrical aberrations and give recommendations on their elimination.

  12. Study of the wavefront aberrations in children with amblyopia

    ZHAO Peng-fei; ZHOU Yue-hua; WANG Ning-li; ZHANG Jing

    2010-01-01

    Background Amblyopia is a common ophthalmological condition and the wavefront aberrometer is a relatively new diagnostic tool used globally to measure optical characteristics of human eyes as well as to study refractive errors in amblyopic eyes. We studied the wavefront aberration of the amblyopic children's eyes and analyzed the mechanism of the wavefront aberration in the formation of the amblyopia, try to investigate the new evidence of the treatment of the amblyopia, especially in the refractory amblyopia.Methods The WaveScan Wavefront System (VISX, USA) aberrometer was used to investigate four groups of children under dark accommodation and cilliary muscle paralysis. There were 45 cases in the metropic group, 87 in the amblyopic group, 92 in the corrected-amblyopic group and 38 in the refractory amblyopic group. One-way analysis of variance (ANOVA), t-test and multivariate linear regression were used to analyze all the data.Results Third order to 6th order aberrations showed a decreasing trend whereas in the higher order aberrations the main ones were 3rd order coma (Z3-1-Z31), trefoil (Z3-3-Z33) and 4th order aberration (Z40); and 3rd order coma represented the highest percentage of all three main aberrations. Within 3rd order coma, vertical coma (Z3-1) accounted for a greater percentage than horizontal coma (Z31). Significant differences of vertical coma were found among all clinical groups of children: vertical coma in the amblyopic group (0.17±0.15) was significantly higher than in the metropic group (0.11±0.13, P0.05).Conclusions Although lower order aberrations such as defocus (myopia and hyperopia) and astigmatism are major factors determining the quality of the retinal image, higher order aberrations also need to be considered in amblyopic eyes as their effects are significant.

  13. Minimum $G_2$-aberration for nonregular fractional factorial designs

    Tang, Boxin; Deng, Lih-Yuan

    1999-01-01

    Deng and Tang proposed generalized resolution and minimum aberration criteria for comparing and assessing nonregular fractional factorials, of which Plackett–Burman designs are special cases.A relaxed variant of generalized aberration is proposed and studied in this paper.We show that a best design according to this criterion minimizes the contamination of nonnegligible interactions on the estimation of main effects in the order of importance given by the hierarchical assump...

  14. Photothermal Lens Aberration Effects in Two Laser Thermal Lens Spectrometry

    Bialkowski, Stephen E.

    1985-01-01

    A comparison of theories describing two laser photothermal lens signals is given. The aberrant nature of this lens is accounted for in a theory which treats the propagation of a monitor laser in terms of a phase shift in this laser beam wave front. The difference between theories are discussed in terms of the predicted signal strengths and temporal behavior. The aberrant theory results in smaller theoretical signal strengths and different functional relationships between signal and analyte le...

  15. Sharpness changes of gaussian beams induced by spherically aberrated lenses

    Piquero, G.; Mejías, P. M.; Martínez-Herrero, R.

    1994-04-01

    Sharpness changes of the spatial profile of a gaussian beam induced by spherically aberrated lenses are investigated in terms of the so-called kurtosis parameter. It is shown both theoretically and experimentally that, after a single aberrated lens, it is possible to get flatter and sharper beam intensity distributions than the input gaussian beam depending on the plane where the field is observed. Agreement between analytical and experimental results is discussed.

  16. Pattern of Chromosomal Aberrations in Patients from North East Iran

    Saeedeh Ghazaey

    2013-01-01

    Full Text Available Objective: Chromosomal aberrations are common causes of multiple anomaly syndromes. Recurrent chromosomal aberrations have been identified by conventional cytogenetic methods used widely as one of the most important clinical diagnostic techniques.Materials and Methods: In this retrospective study, the incidences of chromosomal aberrations were evaluated in a six year period from 2005 to 2011 in Pardis Clinical and Genetics Laboratory on patients referred to from Mashhad and other cities in Khorasan province. Karyotyping was performed on 3728 patients suspected of having chromosomal abnormalities.Results: The frequencies of the different types of chromosomal abnormalities were determined, and the relative frequencies were calculated in each group. Among these patients, 83.3% had normal karyotypes with no aberrations. The overall incidences of chromosomal abnormalities were 16.7% including sex and autosomal chromosomal anomalies. Of those, 75.1 % showed autosomal chromosomal aberrations. Down syndrome (DS was the most prevalent autosomal aberration in the patients (77.1%. Pericentric inversion of chromosome 9 was seen in 5% of patients. This inversion was prevalent in patients with recurrent spontaneous abortion (RSA. Sex chromosomal aberrations were observed in 24.9% of abnormal patients of which 61% had Turner’s syndrome and 33.5% had Klinefelter’s syndrome.Conclusion: According to the current study, the pattern of chromosomal aberrations in North East of Iran demonstrates the importance of cytogenetic evaluation in patients who show clinical abnormalities. These findings provide a reason for preparing a local cytogenetic data bank to enhance genetic counseling of families who require this service.

  17. Neuroanatomical substrates of executive functions: Beyond prefrontal structures.

    Bettcher, Brianne M; Mungas, Dan; Patel, Nihar; Elofson, Jonathan; Dutt, Shubir; Wynn, Matthew; Watson, Christa L; Stephens, Melanie; Walsh, Christine M; Kramer, Joel H

    2016-05-01

    Executive functions are often considered lynchpin "frontal lobe tasks", despite accumulating evidence that a broad network of anterior and posterior brain structures supports them. Using a latent variable modelling approach, we assessed whether prefrontal grey matter volumes independently predict executive function performance when statistically differentiated from global atrophy and individual non-frontal lobar volume contributions. We further examined whether fronto-parietal white matter microstructure underlies and independently contributes to executive functions. We developed a latent variable model to decompose lobar grey matter volumes into a global grey matter factor and specific lobar volumes (i.e. prefrontal, parietal, temporal, occipital) that were independent of global grey matter. We then added mean fractional anisotropy (FA) for the superior longitudinal fasciculus (dorsal portion), corpus callosum, and cingulum bundle (dorsal portion) to models that included grey matter volumes related to cognitive variables in previous analyses. Results suggested that the 2-factor model (shifting/inhibition, updating/working memory) plus an information processing speed factor best explained our executive function data in a sample of 202 community dwelling older adults, and was selected as the base measurement model for further analyses. Global grey matter was related to the executive function and speed variables in all four lobar models, but independent contributions of the frontal lobes were not significant. In contrast, when assessing the effect of white matter microstructure, cingulum FA made significant independent contributions to all three executive function and speed variables and corpus callosum FA was independently related to shifting/inhibition and speed. Findings from the current study indicate that while prefrontal grey matter volumes are significantly associated with cognitive neuroscience measures of shifting/inhibition and working memory in healthy

  18. Precuneus-prefrontal activity during awareness of visual verbal stimuli

    Kjaer, T W; Nowak, M; Kjær, Klaus Wilbrandt;

    2001-01-01

    Awareness is a personal experience, which is only accessible to the rest of world through interpretation. We set out to identify a neural correlate of visual awareness, using brief subliminal and supraliminal verbal stimuli while measuring cerebral blood flow distribution with H(2)(15)O PET....... Awareness of visual verbal stimuli differentially activated medial parietal association cortex (precuneus), which is a polymodal sensory cortex, and dorsolateral prefrontal cortex, which is thought to be primarily executive. Our results suggest participation of these higher order perceptual and executive...... cortical structures in visual verbal awareness....

  19. Lens customization method to minimize aberration in integral imaging

    Miranda, Matheus; Kim, Jonghyun; Hong, Keehoon; Lee, Byoungho

    2015-10-01

    Conventionally the elemental lenses of the lens-array used in integral imaging have spherical surface profiles, thus they suffer from intrinsic lens aberrations such as spherical aberration and astigmatism. Aberrations affect the ability of the lens to focus light in a single point, or to collimate light from a point source. In integral imaging, this results in a loss of image quality of the reconstructed image due to distortions. The viewing characteristics of the integral imaging system, such as viewing angle and image resolution, are also affected by aberrations. We propose the use of a custom made aspherical lens-array which was specifically designed to minimize distortions due to aberrations and hence improve the reconstructed image quality. Ray optics calculations are used in order to analyze the aberrations and find the initial lens surface profile. Lens optimization is performed with the aid of numerical simulation software. The designed lens-array is compared to a conventional spherical lens-array of same properties. The design, optimization, and fabrication processes are described and the experiments are presented and compared with the computer simulations.

  20. Ocular aberrations after wavefront optimized LASIK for myopia

    Padmanabhan Prema

    2010-01-01

    Full Text Available Purpose: To study the change in ocular aberrations after wavefront optimized (WFO laser in situ keratomileusis ( Lasik for correction of myopia and to analyze causative factors that may influence them. Materials and Methods: This was a prospective case series. WFO Lasik was performed for the correction of myopia, using the hansatome (Bausch and Lomb microkeratome to create the flap and the Allegretto laser (Wavelight Technologie to perform the ablation. The Allegretto wave analyser (Tscherning-type measured the ocular aberrations prior to Lasik , one month and six months postoperatively. Results: The mean age of the 59 patients included in the study was 25±5.64 years and the mean spherical equivalent of the 117 eyes that underwent Lasik0 was -5.33±1.22 preoperatively and -0.21±0.38 postoperatively. Hundred and two eyes of 117 (87% achieved uncorrected visual acuity (UCVA of 20/20 or better after WFO Lasik and 104 of 117 eyes (89% were within ±0.5D of the attempted refractive correction. There was a 1.96-fold increase in total root-mean-square of higher order aberrations. Induced changes in seven of the 22 higher order Zernike terms showed a significant linear correlation with the refractive correction attempted. Larger ablation zones induced less spherical aberration. Conclusion: In spite of an excellent visual outcome, WFO Lasik induces significant higher order aberrations. Large ablation zones reduce the induction of spherical aberration.

  1. Are you looking at me? The influence of facial orientation and cultural focus salience on the perception of emotion expressions

    Konstantinos Kafetsios; Ursula Hess

    2015-01-01

    We examined the influence of cultural orientation salience on the emotion perception process in a contextualized emotion recognition task. We primed individual and collective focus in participants who later rated the emotion expressions of a central character (target) showing a happy, sad, angry, or neutral facial expression in a group setting. Facial orientation of a group of four other persons towards the target person was manipulated so that they faced either “inwards,” towards the central...

  2. Terror management theory and the impact of individual and collective mortality salience on symbolic and literal immortality beliefs

    Conrad, Brent

    2009-01-01

    According to Terror Management Theory (TMT), many human behaviors, attitudes, and thoughts are the result of an attempt to reduce the uncomfortable feelings associated with the knowledge that human life is finite. Although many of TMT’s postulates have been supported by research, the assumption that an underlying desire for literal or symbolic immortality is partly responsible for mortality salience responses has received less research attention. Additionally, there has been little research i...

  3. The salience and complexity of building, regulating, and governing the smart grid: Lessons from a statewide public–private partnership

    Smart grid deployment unfolds within a diverse array of multi-institutional arrangements that may be too fragmented and decentralized to allow for the kind of large-scale and coordinated investments needed to properly deploy the smart grid. This case study provides an account of how one state arranged for and eventually deployed smart grid technology to over 85 percent of its resident. The study asks: does the deployment of the smart grid introduce new socio-political variables into the electricity distribution industry? To make sense of the socio-political variables shaping the industry and regulators, the Salience–Complexity Model is used to assess whether the smart grid raises or lowers the level of public scrutiny caste upon the industry (issue salience) and the level of technical capacity needed to execute and utilize the smart grid (technical complexity). The conclusions to be drawn from this study include: smart grid technology heightens the issue salience and the technical complexity of electricity distribution, but that the smart grid will likely not have a significant impact on the restructuring of electricity regulation. - Highlights: • Smart grid introduces new socio-political variables into the electricity distribution industry. • Smart grid technology engenders high degrees of issue salience and technical complexity. • Smart grid deployment requires extensive industry-regulator collaboration. • Smart grid will likely not have a significant impact on the restructuring of electricity regulation

  4. Transcranial phase aberration correction using beam simulations and MR-ARFI

    Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focused ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus

  5. Transcranial phase aberration correction using beam simulations and MR-ARFI

    Vyas, Urvi, E-mail: urvi.vyas@gmail.com; Kaye, Elena; Pauly, Kim Butts [Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2014-03-15

    Purpose: Transcranial magnetic resonance-guided focused ultrasound surgery is a noninvasive technique for causing selective tissue necrosis. Variations in density, thickness, and shape of the skull cause aberrations in the location and shape of the focal zone. In this paper, the authors propose a hybrid simulation-MR-ARFI technique to achieve aberration correction for transcranial MR-guided focused ultrasound surgery. The technique uses ultrasound beam propagation simulations with MR Acoustic Radiation Force Imaging (MR-ARFI) to correct skull-caused phase aberrations. Methods: Skull-based numerical aberrations were obtained from a MR-guided focused ultrasound patient treatment and were added to all elements of the InSightec conformal bone focused ultrasound surgery transducer during transmission. In the first experiment, the 1024 aberrations derived from a human skull were condensed into 16 aberrations by averaging over the transducer area of 64 elements. In the second experiment, all 1024 aberrations were applied to the transducer. The aberrated MR-ARFI images were used in the hybrid simulation-MR-ARFI technique to find 16 estimated aberrations. These estimated aberrations were subtracted from the original aberrations to result in the corrected images. Each aberration experiment (16-aberration and 1024-aberration) was repeated three times. Results: The corrected MR-ARFI image was compared to the aberrated image and the ideal image (image with zero aberrations) for each experiment. The hybrid simulation-MR-ARFI technique resulted in an average increase in focal MR-ARFI phase of 44% for the 16-aberration case and 52% for the 1024-aberration case, and recovered 83% and 39% of the ideal MR-ARFI phase for the 16-aberrations and 1024-aberration case, respectively. Conclusions: Using one MR-ARFI image and noa priori information about the applied phase aberrations, the hybrid simulation-MR-ARFI technique improved the maximum MR-ARFI phase of the beam's focus.

  6. Williams Syndrome Hypersociability: A Neuropsychological Study of the Amygdala and Prefrontal Cortex Hypotheses

    Capitao, Liliana; Sampaio, Adriana; Fernandez, Montse; Sousa, Nuno; Pinheiro, Ana; Goncalves, Oscar F.

    2011-01-01

    Individuals with Williams syndrome display indiscriminate approach towards strangers. Neuroimaging studies conducted so far have linked this social profile to structural and/or functional abnormalities in WS amygdala and prefrontal cortex. In this study, the neuropsychological hypotheses of amygdala and prefrontal cortex involvement in WS…

  7. Revisiting the Role of the Prefrontal Cortex in the Pathophysiology of Attention-Deficit/Hyperactivity Disorder

    Halperin, Jeffrey M.; Schulz, Kurt P.

    2006-01-01

    Most neural models for the pathophysiology of attention-deficit/hyperactivity disorder (ADHD) have centered on the prefrontal cortex and its interconnections with the striatum and other subcortical structures. However, research only partially supports these models, and they do not correspond with the development of the prefrontal cortex and its…

  8. Prefrontal Cortex Cognitive Deficits in Children Treated Early and Continuously for PKU.

    Diamond, Adele; Prevor, Meredith B.; Druin, Donald P.; Callender, Glenda

    1997-01-01

    Hypothesized that elevated ratio of phenylalanine to tyrosine in blood of children with phenylketonuria uniquely affects cognitive functions dependent on prefrontal cortex because of the special sensitivity of prefrontally projecting dopamine neurons to small decreases in tyrosine. Found that children whose phenylalanine levels were three to five…

  9. Dopaminergic Modulation of Medial Prefrontal Cortex Deactivation in Parkinson Depression

    Anders H. Andersen

    2015-01-01

    Full Text Available Parkinson’s disease (PD is associated with emotional abnormalities. Dopaminergic medications ameliorate Parkinsonian motor symptoms, but less is known regarding the impact of dopaminergic agents on affective processing, particularly in depressed PD (dPD patients. The aim of this study was to examine the effects of dopaminergic pharmacotherapy on brain activation to emotional stimuli in depressed versus nondepressed Parkinson disease (ndPD patients. Participants included 18 ndPD patients (11 men, 7 women and 10 dPD patients (7 men, 3 women. Patients viewed photographs of emotional faces during functional MRI. Scans were performed while the patient was taking anti-Parkinson medication and the day after medication had been temporarily discontinued. Results indicate that dopaminergic medications have opposite effects in the prefrontal cortex depending upon depression status. DPD patients show greater deactivation in the ventromedial prefrontal cortex (VMPFC on dopaminergic medications than off, while ndPD patients show greater deactivation in this region off drugs. The VMPFC is in the default-mode network (DMN. DMN activity is negatively correlated with activity in brain systems used for external visual attention. Thus dopaminergic medications may promote increased attention to external visual stimuli among dPD patients but impede normal suppression of DMN activity during external stimulation among ndPD patients.

  10. Dopaminergic Modulation of Medial Prefrontal Cortex Deactivation in Parkinson Depression.

    Andersen, Anders H; Smith, Charles D; Slevin, John T; Kryscio, Richard J; Martin, Catherine A; Schmitt, Frederick A; Blonder, Lee X

    2015-01-01

    Parkinson's disease (PD) is associated with emotional abnormalities. Dopaminergic medications ameliorate Parkinsonian motor symptoms, but less is known regarding the impact of dopaminergic agents on affective processing, particularly in depressed PD (dPD) patients. The aim of this study was to examine the effects of dopaminergic pharmacotherapy on brain activation to emotional stimuli in depressed versus nondepressed Parkinson disease (ndPD) patients. Participants included 18 ndPD patients (11 men, 7 women) and 10 dPD patients (7 men, 3 women). Patients viewed photographs of emotional faces during functional MRI. Scans were performed while the patient was taking anti-Parkinson medication and the day after medication had been temporarily discontinued. Results indicate that dopaminergic medications have opposite effects in the prefrontal cortex depending upon depression status. DPD patients show greater deactivation in the ventromedial prefrontal cortex (VMPFC) on dopaminergic medications than off, while ndPD patients show greater deactivation in this region off drugs. The VMPFC is in the default-mode network (DMN). DMN activity is negatively correlated with activity in brain systems used for external visual attention. Thus dopaminergic medications may promote increased attention to external visual stimuli among dPD patients but impede normal suppression of DMN activity during external stimulation among ndPD patients. PMID:26793404

  11. Ventromedial prefrontal cortex, adding value to autobiographical memories.

    Lin, Wen-Jing; Horner, Aidan J; Burgess, Neil

    2016-01-01

    The medial prefrontal cortex (mPFC) has been consistently implicated in autobiographical memory recall and decision making. Its function in decision making tasks is believed to relate to value representation, but its function in autobiographical memory recall is not yet clear. We hypothesised that the mPFC represents the subjective value of elements during autobiographical memory retrieval. Using functional magnetic resonance imaging during an autobiographical memory recall task, we found that the blood oxygen level dependent (BOLD) signal in ventromedial prefrontal cortex (vmPFC) was parametrically modulated by the affective values of items in participants' memories when they were recalling and evaluating these items. An unrelated modulation by the participant's familiarity with the items was also observed. During retrieval of the event, the BOLD signal in the same region was modulated by the personal significance and emotional intensity of the memory, which was correlated with the values of the items within them. These results support the idea that vmPFC processes self-relevant information, and suggest that it is involved in representing the personal emotional values of the elements comprising autobiographical memories. PMID:27338616

  12. Higher Order Spike Synchrony in Prefrontal Cortex during Visual Memory.

    Pipa, Gordon; Munk, Matthias H J

    2011-01-01

    Precise temporal synchrony of spike firing has been postulated as an important neuronal mechanism for signal integration and the induction of plasticity in neocortex. As prefrontal cortex plays an important role in organizing memory and executive functions, the convergence of multiple visual pathways onto PFC predicts that neurons should preferentially synchronize their spiking when stimulus information is processed. Furthermore, synchronous spike firing should intensify if memory processes require the induction of neuronal plasticity, even if this is only for short-term. Here we show with multiple simultaneously recorded units in ventral prefrontal cortex that neurons participate in 3 ms precise synchronous discharges distributed across multiple sites separated by at least 500 μm. The frequency of synchronous firing is modulated by behavioral performance and is specific for the memorized visual stimuli. In particular, during the memory period in which activity is not stimulus driven, larger groups of up to seven sites exhibit performance dependent modulation of their spike synchronization. PMID:21713065

  13. Medial prefrontal cortex role in recognition memory in rodents.

    Morici, Juan Facundo; Bekinschtein, Pedro; Weisstaub, Noelia V

    2015-10-01

    The study of the neurobiology of recognition memory, defined by the integration of the different components of experiences that support recollection of past experiences have been a challenge for memory researches for many years. In the last twenty years, with the development of the spontaneous novel object recognition task and all its variants this has started to change. The features of recognition memory include a particular object or person ("what"), the context in which the experience took place, which can be the arena itself or the location within a particular arena ("where") and the particular time at which the event occurred ("when"). This definition instead of the historical anthropocentric one allows the study of this type of episodic memory in animal models. Some forms of recognition memory that require integration of different features recruit the medial prefrontal cortex. Focusing on findings from spontaneous recognition memory tasks performed by rodents, this review concentrates on the description of previous works that have examined the role that the medial prefrontal cortex has on the different steps of recognition memory. We conclude that this structure, independently of the task used, is required at different memory stages when the task cannot be solved by a single item strategy. PMID:26115848

  14. Modelling of multi-conjugate adaptive optics for spatially variant aberrations in microscopy

    Adaptive optics has been implemented in a range of high-resolution microscopes in order to overcome the problems of specimen-induced aberrations. Most implementations have used a single aberration correction across the imaged field. It is known, however, that aberrations often vary across the field of view, so a single correction setting cannot compensate all aberrations. Multi-conjugate adaptive optics (MCAO) has been suggested as a possible method for correction of these spatially variant aberrations. MCAO is modelled to simulate the correction of aberrations, both for simple model specimens and using real aberration data from a biological specimen. (special issue article)

  15. Functional organization and visual representations in human ventral lateral prefrontal cortex

    Annie Wai Yiu Chan

    2013-07-01

    Full Text Available Recent neuroimaging studies in both human and non-human primates have identified face selective activation in the ventral lateral prefrontal cortex even in the absence of working memory demands. Further, research has suggested that this face-selective response is largely driven by the presence of the eyes. However, the nature and origin of visual category responses in the ventral lateral prefrontal cortex remain unclear. Further, in a broader sense, how do these findings relate to our current understandings of lateral prefrontal cortex? What do these findings tell us about the underlying function and organization principles of the ventral lateral prefrontal cortex? What is the future direction for investigating visual representations in this cortex? This review focuses on the function, topography, and circuitry of the ventral lateral prefrontal cortex to enhance our understanding of the evolution and development of this cortex.

  16. Neurochemical metabolites in the medial prefrontal cortex in bipolar disorder A proton magnetic resonance spectroscopy study

    Osman (O)zdel; Demet Kalayci; Gülfizar S(o)zeri-Varma; Yilmaz Kiro(g)lu; Selim Tümkaya; Tu(g)(c)e Toker-U(g)urlu

    2012-01-01

    The aim of this study was to investigate proton magnetic resonance spectroscopy metabolite values in the medial prefrontal cortex of individuals with euthymic bipolar disorder. The subjects consisted of 15 patients with euthymic bipolar disorder type I and 15 healthy controls. We performed proton magnetic resonance spectroscopy of the bilateral medial prefrontal cortex and measured levels of N-acetyl aspartate, choline and creatine. Levels of these three metabolites in the medial prefrontal cortex were found to be lower in patients with bipolar disorder compared with healthy controls. A positive correlation was found between illness duration and choline levels in the right medial prefrontal cortex. Our study suggests that during the euthymic period, there are abnormalities in cellular energy and membrane phospholipid metabolism in the medial prefrontal cortex, and that this may impair neuronal activity and integrity.

  17. Distinct Roles of the Prefrontal and Posterior Parietal Cortices in Response Inhibition

    Xin Zhou

    2016-03-01

    Full Text Available The dorsolateral prefrontal cortex and posterior parietal cortex have been implicated in the planning of movements and inhibition of inappropriate responses, though their precise roles in these functions are not known. To address this question, we trained monkeys to perform memory-guided saccade and anti-saccade tasks and compared neural responses in the same animals. A population of neurons with no motor responses was also activated by a stimulus appearing out of the receptive field and could therefore mediate vector inversion. These neurons were found almost exclusively in the prefrontal cortex. Prefrontal cortical activity better predicted the level of performance in the task. Representation of the saccade goal also peaked in the prefrontal cortex at a time that was predictive of reaction time. These results suggest that the prefrontal cortex is the primary site of vector inversion in the cerebral cortex and explain the importance of this area in response inhibition.

  18. Induction of chromosomal aberrations in human lymphocytes by fission neutrons

    Chromosome aberrations induced by sparsely ionizing radiation (low-LET) are well known and cytogenetic analyses of irradiated human lymphocytes have been widely applied to biological dosimetry. However, much less is known about chromosome aberrations induced by densely ionizing radiation (high LET), such as that of alpha particles or neutrons. Such particles induce DNA strand breaks, as well as chromosome breakage and rearrangements of high complexity. This damage is more localized and less efficiently repaired than after X- or γ-ray irradiation. This preferential production of complex aberrations by densely ionizing radiation is related to the unique energy deposition patterns, which produces highly localized multiple DNA damage at the chromosomal level. A better knowledge of the interactions between different types of radiation and cellular DNA is of importance, not only from the radiobiological viewpoint but also for dosimetric and therapeutic purposes. The objective of the present study was to analyse the cytogenetic effects of fission neutrons on peripheral blood lymphocytes in order to evaluate structural and numerical aberrations and number of cells in the different mitotic cycles. So, blood samples from five healthy donors, 22-25 years old, of both sexes, were irradiated in the Research Reactor IEA-R1 of our Institute (IPEN/CNEN-SP) with thermal and fast neutrons at doses of 0.2; 0.3; 0.5 and 1.0 Gy. The γ contribution to the total absorbed dose was about 30%. These doses were monitored by thermoluminescent dosemeters: LiF-600 (for neutrons) and LiF-700 (for γ-rays). The data concerning structural aberrations were evaluated with regard to three parameters: percentage of cells with aberrations, number of aberrations/cell and number of dicentric/cell. The cytogenetic results showed an increase in the three parameters after irradiation with neutrons, as a function of radiation dose. Apparently, there was no influence of neutrons on the kinetics of cellular

  19. Cue salience influences the use of height cues in reorientation in pigeons (Columba livia).

    Du, Yu; Mahdi, Nuha; Paul, Breanne; Spetch, Marcia L

    2016-07-01

    Although orienting ability has been examined with numerous types of cues, most research has focused only on cues from the horizontal plane. The current study investigated pigeons' use of wall height, a vertical cue, in an open-field task and compared it with their use of horizontal cues. Pigeons were trained to locate food in 2 diagonal corners of a rectangular enclosure with 2 opposite high walls as height cues. Before each trial, pigeons were rotated to disorient them. In training, pigeons could use either the horizontal cues from the rectangular enclosure or the height information from the walls to locate the food. In testing, the apparatus was modified to provide (a) horizontal cues only, (b) height cues only, and (c) both height and horizontal cues in conflict. In Experiment 1 the lower and high walls, respectively, were 40 and 80 cm, whereas in Experiment 2 they were made more perceptually salient by shortening them to 20 and 40 cm. Pigeons accurately located the goal corners with horizontal cues alone in both experiments, but they searched accurately with height cues alone only in Experiment 2. When the height cues conflicted with horizontal cues, pigeons preferred the horizontal cues over the height cues in Experiment 1 but not in Experiment 2, suggesting that perceptual salience influences the relative weighting of cues. (PsycINFO Database Record PMID:27379717

  20. Effects of salience-network-node neurofeedback training on affective biases in major depressive disorder.

    Hamilton, J Paul; Glover, Gary H; Bagarinao, Epifanio; Chang, Catie; Mackey, Sean; Sacchet, Matthew D; Gotlib, Ian H

    2016-03-30

    Neural models of major depressive disorder (MDD) posit that over-response of components of the brain's salience network (SN) to negative stimuli plays a crucial role in the pathophysiology of MDD. In the present proof-of-concept study, we tested this formulation directly by examining the affective consequences of training depressed persons to down-regulate response of SN nodes to negative material. Ten participants in the real neurofeedback group saw, and attempted to learn to down-regulate, activity from an empirically identified node of the SN. Ten other participants engaged in an equivalent procedure with the exception that they saw SN-node neurofeedback indices from participants in the real neurofeedback group. Before and after scanning, all participants completed tasks assessing emotional responses to negative scenes and to negative and positive self-descriptive adjectives. Compared to participants in the sham-neurofeedback group, from pre- to post-training, participants in the real-neurofeedback group showed a greater decrease in SN-node response to negative stimuli, a greater decrease in self-reported emotional response to negative scenes, and a greater decrease in self-reported emotional response to negative self-descriptive adjectives. Our findings provide support for a neural formulation in which the SN plays a primary role in contributing to negative cognitive biases in MDD. PMID:26862057

  1. Brain responses to emotional salience and reward in alcohol use disorder.

    Alba-Ferrara, L; Müller-Oehring, E M; Sullivan, E V; Pfefferbaum, A; Schulte, T

    2016-03-01

    Heightened neural responsiveness of alcoholics to alcohol cues and social emotion may impede sobriety. To test mesocorticolimbic network responsivity, 10 (8 men) alcohol use disorder (AUD) patients sober for 3 weeks to 10 months and 11 (8 men) controls underwent fMRI whilst viewing pictures of alcohol and non-alcohol beverages and of emotional faces (happy, sad, angry). AUD and controls showed similarities in mesocorticolimbic activity: both groups activated fusiform for emotional faces and hippocampal and pallidum regions during alcohol picture processing. In AUD, less fusiform activity to emotional faces and more pallidum activity to alcohol pictures were associated with longer sobriety. Using graph theory-based network efficiency measures to specify the role of the mesocorticolimbic network nodes for emotion and reward in sober AUD revealed that the left hippocampus was less efficiently connected with the other task-activated network regions in AUD than controls when viewing emotional faces, while the pallidum was more efficiently connected when viewing alcohol beverages. Together our findings identified lower occipito-temporal sensitivity to emotional faces and enhanced striatal sensitivity to alcohol stimuli in AUD than controls. Considering the role of the striatum in encoding reward, its activation enhancement with longer sobriety may reflect adaptive neural changes in the first year of drinking cessation and mesocorticolimbic system vulnerability for encoding emotional salience and reward potentially affecting executive control ability and relapse propensity during abstinence. PMID:25875013

  2. The salience and severity of relationship problems among low-income couples.

    Jackson, Grace L; Trail, Thomas E; Kennedy, David P; Williamson, Hannah C; Bradbury, Thomas N; Karney, Benjamin R

    2016-02-01

    Developing programs to support low-income married couples requires an accurate understanding of the challenges they face. To address this question, we assessed the salience and severity of relationship problems by asking 862 Black, White, and Latino newlywed spouses (N = 431 couples) living in low-income neighborhoods to (a) free list their 3 biggest sources of disagreement in the marriage, and (b) rate the severity of the problems appearing on a standard relationship problem inventory. Comparing the 2 sources of information revealed that, although relational problems (e.g., communication and moods) were rated as severe on the inventory, challenges external to the relationship (e.g., children) were more salient in the free listing task. The pattern of results is robust across couples of varying race/ethnicity, parental status, and income levels. We conclude that efforts to strengthen marriages among low-income couples may be more effective if they address not only relational problems, but also couples' external stresses by providing assistance with child care, finances, or job training. PMID:26571196

  3. Interactions between the salience and default-mode networks are disrupted in cocaine addiction.

    Liang, Xia; He, Yong; Salmeron, Betty Jo; Gu, Hong; Stein, Elliot A; Yang, Yihong

    2015-05-27

    Cocaine dependence is a complex neuropsychiatric disorder manifested as dysregulation of multiple behavioral, emotional, and cognitive constructs. Neuroimaging studies have begun to identify specific neurobiological circuit impairments in cocaine-dependent (CD) individuals that may underlie these symptoms. However, whether, where, and how the interactions within and between these circuits are disrupted remain largely unknown. We used resting-state fMRI and modularity network analysis to identify brain modules of a priori interest (default-mode network [DMN], salience network [SN], executive control network [ECN], medial temporal lobe [MTL], and striatum) in 47 CD and 47 matched healthy control (HC) participants and explored alterations within and between these brain modules as a function of addiction. At the module level, intermodule connectivity decreased between DMN and SN in CD. At the nodal level, several regions showed decreased connections with multiple modules in CD: the rostral anterior cingulate connection strength was reduced with SN and MTL; the posterior cingulate had reduced connections with ECN; and the bilateral insula demonstrated decreased connections with DMN. Furthermore, alexithymia, a personality trait previously associated with addiction, correlated negatively with intramodule connectivity within SN only in cocaine users. Our results indicate that cocaine addiction is associated with disrupted interactions among DMN, MTL, and SN, which have been implicated, respectively, in self-referential functions, emotion and memory, and coordinating between internal and external stimuli, providing novel and important insights into the neurobiological mechanisms of cocaine addiction. PMID:26019326

  4. Visual assessment of BIPV retrofit design proposals for selected historical buildings using the saliency map method

    Ran Xu

    2015-06-01

    Full Text Available With the increasing awareness of energy efficiency, many old buildings have to undergo a massive facade energy retrofit. How to predict the visual impact which solar installations on the aesthetic cultural value of these buildings has been a heated debate in Switzerland (and throughout the world. The usual evaluation method to describe the visual impact of BIPV is based on semantic and qualitative descriptors, and strongly dependent on personal preferences. The evaluation scale is therefore relative, flexible and imprecise. This paper proposes a new method to accurately measure the visual impact which BIPV installations have on a historical building by using the saliency map method. By imitating working principles of the human eye, it is measured how much the BIPV design proposals differ from the original building facade in the aspect of attracting human visual attention. The result is directly presented in a quantitative manner, and can be used to compare the fitness of different BIPV design proposals. The measuring process is numeric, objective and more precise.  

  5. Metabolic mapping reveals sex-dependent involvement of default mode and salience network in alexithymia.

    Colic, L; Demenescu, L R; Li, M; Kaufmann, J; Krause, A L; Metzger, C; Walter, M

    2016-02-01

    Alexithymia, a personality construct marked by difficulties in processing one's emotions, has been linked to the altered activity in the anterior cingulate cortex (ACC). Although longitudinal studies reported sex differences in alexithymia, what mediates them is not known. To investigate sex-specific associations of alexithymia and neuronal markers, we mapped metabolites in four brain regions involved differentially in emotion processing using a point-resolved spectroscopy MRS sequence in 3 Tesla. Both sexes showed negative correlations between alexithymia and N-acetylaspartate (NAA) in pregenual ACC (pgACC). Women showed a robust negative correlation of the joint measure of glutamate and glutamine (Glx) to NAA in posterior cingulate cortex (PCC), whereas men showed a weak positive association of Glx to NAA in dorsal ACC (dACC). Our results suggest that lowered neuronal integrity in pgACC, a region of the default mode network (DMN), might primarily account for the general difficulties in emotional processing in alexithymia. Association of alexithymia in women extends to another region in the DMN-PCC, while in men a region in the salience network (SN) was involved. These observations could be representative of sex specific regulation strategies that include diminished internal evaluation of feelings in women and cognitive emotion suppression in men. PMID:26341904

  6. Mortality salience enhances racial in-group bias in empathic neural responses to others' suffering.

    Li, Xiaoyang; Liu, Yi; Luo, Siyang; Wu, Bing; Wu, Xinhuai; Han, Shihui

    2015-09-01

    Behavioral research suggests that mortality salience (MS) leads to increased in-group identification and in-group favoritism in prosocial behavior. What remains unknown is whether and how MS influences brain activity that mediates emotional resonance with in-group and out-group members and is associated with in-group favoritism in helping behavior. The current work investigated MS effects on empathic neural responses to racial in-group and out-group members' suffering. Experiments 1 and 2 respectively recorded event related potentials (ERPs) and blood oxygen level dependent signals to pain/neutral expressions of Asian and Caucasian faces from Chinese adults who had been primed with MS or negative affect (NA). Experiment 1 found that an early frontal/central activity (P2) was more strongly modulated by pain vs. neutral expressions of Asian than Caucasian faces, but this effect was not affected by MS vs. NA priming. However, MS relative to NA priming enhanced racial in-group bias in long-latency neural response to pain expressions over the central/parietal regions (P3). Experiment 2 found that MS vs. NA priming increased racial in-group bias in empathic neural responses to pain expression in the anterior and mid-cingulate cortex. Our findings indicate that reminding mortality enhances brain activity that differentiates between racial in-group and out-group members' emotional states and suggest a neural basis of in-group favoritism under mortality threat. PMID:26074201

  7. Detection of Harbours from High Resolution Remote Sensing Imagery via Saliency Analysis and Feature Learning

    Wang, Yetianjian; Pan, Li; Wang, Dagang; Kang, Yifei

    2016-06-01

    Harbours are very important objects in civil and military fields. To detect them from high resolution remote sensing imagery is important in various fields and also a challenging task. Traditional methods of detecting harbours mainly focus on the segmentation of water and land and the manual selection of knowledge. They do not make enough use of other features of remote sensing imagery and often fail to describe the harbours completely. In order to improve the detection, a new method is proposed. First, the image is transformed to Hue, Saturation, Value (HSV) colour space and saliency analysis is processed via the generation and enhancement of the co-occurrence histogram to help detect and locate the regions of interest (ROIs) that is salient and may be parts of the harbour. Next, SIFT features are extracted and feature learning is processed to help represent the ROIs. Then, by using classified feature of the harbour, a classifier is trained and used to check the ROIs to find whether they belong to the harbour. Finally, if the ROIs belong to the harbour, a minimum bounding rectangle is formed to include all the harbour ROIs and detect and locate the harbour. The experiment on high resolution remote sensing imagery shows that the proposed method performs better than other methods in precision of classifying ROIs and accuracy of completely detecting and locating harbours.

  8. Modeling Visual Exploration in Rhesus Macaques with Bottom-Up Salience and Oculomotor Statistics

    König, Seth D.; Buffalo, Elizabeth A.

    2016-01-01

    There is a growing interest in studying biological systems in natural settings, in which experimental stimuli are less artificial and behavior is less controlled. In primate vision research, free viewing of complex images has elucidated novel neural responses, and free viewing in humans has helped discover attentional and behavioral impairments in patients with neurological disorders. In order to fully interpret data collected from free viewing of complex scenes, it is critical to better understand what aspects of the stimuli guide viewing behavior. To this end, we have developed a novel viewing behavior model called a Biased Correlated Random Walk (BCRW) to describe free viewing behavior during the exploration of complex scenes in monkeys. The BCRW can predict fixation locations better than bottom-up salience. Additionally, we show that the BCRW can be used to test hypotheses regarding specific attentional mechanisms. For example, we used the BCRW to examine the source of the central bias in fixation locations. Our analyses suggest that the central bias may be caused by a natural tendency to reorient the eyes toward the center of the stimulus, rather than a photographer's bias to center salient items in a scene. Taken together these data suggest that the BCRW can be used to further our understanding of viewing behavior and attention, and could be useful in optimizing stimulus and task design.

  9. The concept of salience network dysfunction in schizophrenia: from neuroimaging observations to therapeutic opportunities.

    Palaniyappan, L; White, T P; Liddle, P F

    2012-01-01

    A large body of neuroimaging literature suggests that distributed regions in the brain form coordinated largescale networks that show reliable patterns of connectivity when observed using either functional or structural magnetic resonance imaging (MRI) methods. Functional activation within these networks provides a robust and reliable representation of dynamic brain states observed during information processing. One such network comprised of anterior frontoinsular cortex (aFI) and anterior cingulate cortex (ACC) is called the Salience Network (SN). SN has been identified as a system that enables the switch between various dynamic brain states. SN dysfunction has been proposed as a mechanistic model for several core symptoms of schizophrenia. In this review, we explore how various risk factors of schizophrenia could operate through the dysfunctional SN to generate symptoms of psychosis. We also consider the putative neurochemical basis for the SN dysfunction in schizophrenia, and suggest that the SN dysfunction is a viable therapeutic target for a combined pharmacological and cognitive training treatment approach. This combination approach, termed as Brain Network Modulation, could exploit neuronal plasticity to reverse a key pathophysiological deficit in schizophrenia. PMID:23279173

  10. The impact of napping on memory for future-relevant stimuli: Prioritization among multiple salience cues.

    Bennion, Kelly A; Payne, Jessica D; Kensinger, Elizabeth A

    2016-06-01

    Prior research has demonstrated that sleep enhances memory for future-relevant information, including memory for information that is salient due to emotion, reward, or knowledge of a later memory test. Although sleep has been shown to prioritize information with any of these characteristics, the present study investigates the novel question of how sleep prioritizes information when multiple salience cues exist. Participants encoded scenes that were future-relevant based on emotion (emotional vs. neutral), reward (rewarded vs. unrewarded), and instructed learning (intentionally vs. incidentally encoded), preceding a delay consisting of a nap, an equivalent time period spent awake, or a nap followed by wakefulness (to control for effects of interference). Recognition testing revealed that when multiple dimensions of future relevance co-occur, sleep prioritizes top-down, goal-directed cues (instructed learning, and to a lesser degree, reward) over bottom-up, stimulus-driven characteristics (emotion). Further, results showed that these factors interact; the effect of a nap on intentionally encoded information was especially strong for neutral (relative to emotional) information, suggesting that once one cue for future relevance is present, there are diminishing returns with additional cues. Sleep may binarize information based on whether it is future-relevant or not, preferentially consolidating memory for the former category. Potential neural mechanisms underlying these selective effects and the implications of this research for educational and vocational domains are discussed. (PsycINFO Database Record PMID:27214500

  11. Immersive audiomotor game play enhances neural and perceptual salience of weak signals in noise.

    Whitton, Jonathon P; Hancock, Kenneth E; Polley, Daniel B

    2014-06-24

    All sensory systems face the fundamental challenge of encoding weak signals in noisy backgrounds. Although discrimination abilities can improve with practice, these benefits rarely generalize to untrained stimulus dimensions. Inspired by recent findings that action video game training can impart a broader spectrum of benefits than traditional perceptual learning paradigms, we trained adult humans and mice in an immersive audio game that challenged them to forage for hidden auditory targets in a 2D soundscape. Both species learned to modulate their angular search vectors and target approach velocities based on real-time changes in the level of a weak tone embedded in broadband noise. In humans, mastery of this tone in noise task generalized to an improved ability to comprehend spoken sentences in speech babble noise. Neural plasticity in the auditory cortex of trained mice supported improved decoding of low-intensity sounds at the training frequency and an enhanced resistance to interference from background masking noise. These findings highlight the potential to improve the neural and perceptual salience of degraded sensory stimuli through immersive computerized games. PMID:24927596

  12. Antimutagenic potential of curcumin on chromosomal aberrations in Allium cepa

    RAGUNATHAN Irulappan; PANNEERSELVAM Natarajan

    2007-01-01

    Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 μg/ml for 3 h and curcumin was given at 5, 10 and 20 μg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 μg/ml in Allium cepa root meristem cells.

  13. Metaphase chromosome aberrations as markers of radiation exposure and dose

    Chromosome aberration frequency provides the most reliable biological marker of dose for detecting acute accidental radiation exposure. Significant radiation-induced changes in the frequency of chromosome aberrations can be detected at very low doses. Our paper provides information on using molecular chromosome probes ''paints'' to score chromosome damage and illustrates how technical advances make it possible to understand mechanisms involved during formation of chromosome aberrations. In animal studies chromosome aberrations provide a method to relate cellular damage to cellular dose. Using an In vivo/In vitro approach aberrations provided a biological marker of dose from radon progeny exposure which was used to convert WLM to dose in rat tracheal epithelial cells. Injection of Chinese hamsters with 144Ce which produced a low dose rate exposure of bone marrow to either low-LET radiation increased the sensitivity of the cells to subsequent external exposure to 60Co. These studies demonstrated the usefulness of chromosome damage as a biological marker of dose and cellular responsiveness

  14. Split-plot fractional designs: Is minimum aberration enough?

    Kulahci, Murat; Ramirez, Jose; Tobias, Randy

    2006-01-01

    Split-plot experiments are commonly used in industry for product and process improvement. Recent articles on designing split-plot experiments concentrate on minimum aberration as the design criterion. Minimum aberration has been criticized as a design criterion for completely randomized fractional...... factorial design and alternative criteria, such as the maximum number of clear two-factor interactions, are suggested (Wu and Hamada (2000)). The need for alternatives to minimum aberration is even more acute for split-plot designs. In a standard split-plot design, there are several types of two...... completely randomized designs. Consequently, we provide a modified version of the maximum number of clear two-factor interactions design criterion to be used for split-plot designs....

  15. Biological dosimetry: chromosomal aberration analysis for dose assessment

    In view of the growing importance of chromosomal aberration analysis as a biological dosimeter, the present report provides a concise summary of the scientific background of the subject and a comprehensive source of information at the technical level. After a review of the basic principles of radiation dosimetry and radiation biology basic information on the biology of lymphocytes, the structure of chromosomes and the classification of chromosomal aberrations are presented. This is followed by a presentation of techniques for collecting blood, storing, transporting, culturing, making chromosomal preparations and scaring of aberrations. The physical and statistical parameters involved in dose assessment are discussed and examples of actual dose assessments taken from the scientific literature are given

  16. Measurement of the atmospheric primary aberrations by 4-aperture DIMM

    Shomali, Ramin; Darudi, Ahmad

    2011-01-01

    The present paper investigates and discusses the ability of the Hartmann test with 4-aperture DIMM to measure the atmospheric primary aberrations which, in turn, can be used for calculation of the atmospheric coherence time. Through performing numerical simulations, we show that the 4-aperture DIMM is able to measure the defocus and astigmatism terms correctly while its results are not reliable for the coma. The most important limitation in the measurement of the primary aberrations by 4-aperture DIMM is the centroid displacements of the spots which are caused by the higher order aberrations. This effect is negligible in calculating of the defocus and astigmatisms, while, it cannot be ignored in the calculation of the coma.

  17. Correcting the Chromatic Aberration in Barrel Distortion of Endoscopic Images

    Y. M. Harry Ng

    2003-04-01

    Full Text Available Modern endoscopes offer physicians a wide-angle field of view (FOV for minimally invasive therapies. However, the high level of barrel distortion may prevent accurate perception of image. Fortunately, this kind of distortion may be corrected by digital image processing. In this paper we investigate the chromatic aberrations in the barrel distortion of endoscopic images. In the past, chromatic aberration in endoscopes is corrected by achromatic lenses or active lens control. In contrast, we take a computational approach by modifying the concept of image warping and the existing barrel distortion correction algorithm to tackle the chromatic aberration problem. In addition, an error function for the determination of the level of centroid coincidence is proposed. Simulation and experimental results confirm the effectiveness of our method.

  18. Screening for aberrant behavior in the nuclear industry

    This paper attempts to promote a fuller understanding of how psychological assessment procedures can be used to reduce the threat from aberrant behavior in the nuclear industry. It begins with a discussion of the scientifically based methods that are used by psychologists in constructing, scoring, and interpreting these procedures. This discussion includes an emphasis on the concepts of validity and reliability and their central importance when one is choosing specific psychological screening tools. Criteria for selecting and using psychological assessment procedures when screening for aberrant behavior are also provided. Some commonly used assessment procedures that satisfy these criteria are discussed. A number a psychological assessment procedures specifically recommended for use in screening for aberrant behavior in the nuclear industry are described

  19. On-line correction of aberrations in particle spectrographs

    A new method is presented that allows the reconstruction of trajectories and the on-line correction of residual aberrations that limit the resolution of particle spectrographs. Using a computed or fitted high order transfer map that describes the uncorrected aberrations of the spectrograph under consideration, it is possible to determine a pseudo transfer map that allows the computation of the corrected data of interest as well as the reconstructed trajectories in terms of position measurements in two planes near the focal plane. The technique is only limited by the accuracy of the position measurements and the accuracy of the transfer map. In practice the method can be expressed as an inversion of a pseudo transfer map and implemented in the differential algebraic framework. The method will be used to correct residual high aberrations in the S800 spectrograph which is under construction at the National Superconducting Cyclotron Laboratory at Michigan State University

  20. Subwavelength-grating-induced wavefront aberrations: a case study

    Crabtree, Karlton; Chipman, Russell A.

    2007-07-01

    The on-axis wavefront aberrations of a one-dimensional subwavelength-grating antireflection coating on an f/1.7 lens surface are shown to be small with noticeable contributions of defocus, astigmatism, and piston. The astigmatism is 0.02 wave, and the magnitude of the piston approaches one wave peak-to-valley. The difference in aberrations between orthogonally polarized wavefronts, or the retardance aberration, shows 0.01 wave of astigmatismlike variation and more than 0.01 wave of retardance-induced defocuslike variation. A small coupling between polarization states occurs in the form of the familiar Maltese cross, yielding a maximum of 3% coupling in the four diagonal edges of the pupil.

  1. Non-Gaussianity and CMB aberration and Doppler

    Catena, Riccardo; Notari, Alessio; Renzi, Alessandro

    2013-01-01

    The peculiar motion of an observer with respect to the CMB rest frame induces a deflection in the arrival direction of the observed photons (also known as CMB aberration) and a Doppler shift in the measured photon frequencies. As a consequence, aberration and Doppler effects induce non trivial correlations between the harmonic coefficients of the observed CMB temperature maps. In this paper we investigate whether these correlations generate a bias on Non-Gaussianity estimators $f_{NL}$. We perform this analysis simulating a large number of temperature maps with Planck-like resolution (lmax $= 2000$) as different realizations of the same cosmological fiducial model (WMAP7yr). We then add to these maps aberration and Doppler effects employing a modified version of the HEALPix code. We finally evaluate a generalization of the Komatsu, Spergel and Wandelt Non-Gaussianity estimator for all the simulated maps, both when peculiar velocity effects have been considered and when these phenomena have been neglected. Usi...

  2. Radiation-induced chromosome aberrations in human lymphocytes

    Dose-response relationships for unstable chromosome exchange aberrations were obtained after irradiation with 200 kV X-rays and 60Co gamma rays, the doses ranging within 0.05-3.0 Gy. The data points were fitted to the linear quadratic model Y = C + αD + βD2, and after the chromosome hits leading to two-break unstable aberrations were estimated, to the model average x = C +kD. The results fitted the latter model particularly well, the index of determination being 0.988 for gamma rays and 0.997 for X-rays. The RBE of 200 kV X-rays as compared with 60Co gamma radiation was 1.6, when primary chromosome breaks leading to dicentric and centric ring aberrations were used as the biological endpoint. (author)

  3. Split-plot fractional designs: Is minimum aberration enough?

    Kulahci, Murat; Ramirez, Jose; Tobias, Randy

    2006-01-01

    Split-plot experiments are commonly used in industry for product and process improvement. Recent articles on designing split-plot experiments concentrate on minimum aberration as the design criterion. Minimum aberration has been criticized as a design criterion for completely randomized fractional...... factorial design and alternative criteria, such as the maximum number of clear two-factor interactions, are suggested (Wu and Hamada (2000)). The need for alternatives to minimum aberration is even more acute for split-plot designs. In a standard split-plot design, there are several types of two...... for completely randomized designs. Consequently, we provide a modified version of the maximum number of clear two-factor interactions design criterion to be used for split-plot designs....

  4. Stability of chromosome aberrations with post-irradiation time. Implications in retrospective biodosimetry. Chromosome aberration analysis in retrospective biodosimetry

    The aim of the present study was to evaluate the persistence chromosome aberrations induced by three doses of X-rays. For this purpose fluorescence in situ hybridisation (FISH) painting and multiplex FISH (mFISH) techniques have been applied to a long-term culture of irradiated cells. By painting, at 2 Gy the frequency of apparently simple translocations remained almost invariable during all the culture, whereas at 4 Gy a rapid decline was observed between the first and the second sample, followed by a slight decrease until the end of the culture. Apparently simple dicentrics and complex aberrations disappeared after the first sample at 2 and 4 Gy. When simple aberrations analysed by mFISH are considered, at 2 Gy the frequency of complete plus one-way translocations remained invariable between the first and last sample, but at 4 Gy a 60% decline was observed. True incomplete simple translocations disappeared at 2 and 4 Gy. The analysis by mFISH showed that the frequency of complex aberrations and their complexity increased with dose and tends to disappear in the last sample. Our results indicate that the dose influence on the decrease of the frequency of simple translocations with post-irradiation time cannot be fully explained by the disappearance of true incomplete translocations and complex aberrations. (author)

  5. Watching cartoons activates the medial prefrontal cortex in children

    2007-01-01

    The medial prefrontal cortex (MPFC) of human adults is involved in attributing mental states to real human agents but not to virtual artificial characters. This study examined whether such differential MPFC activity can be observed in children who are more fascinated by cartoons than adults. We measured brain activity using functional magnetic resonance imaging (fMRI) while 10-year-old children watched movie and cartoon clips, simulating real and virtual visual worlds, respectively. We showed neuroimaging evidence that, in contrast to adults, the MPFC of children was activated when perceiving both human agents and artificial characters in coherent visual events. Our findings suggest that, around the age of 10 years, the MPFC activity in children is different from that in adults in that it can be spontaneously activated by non-human agents in a virtual visual world.

  6. MDMA (ecstasy) modulates locomotor and prefrontal cortex sensory evoked activity.

    Atkins, Kristal; Burks, Tilithia; Swann, Alan C; Dafny, Nachum

    2009-12-11

    Ingestion of 3, 4-methylenedioxymethamphetamine (MDMA) leads to heightened response to sensory stimulation; thus, MDMA is referred to as "ecstasy" because it produces pleasurable enhancement of such sensation. There have been no electrophysiological studies that report the consequences of MDMA on sensory input. The present study was initiated to study the effects of acute and chronic MDMA on locomotor activity and sensory evoked field potential from freely behaving rats previously implanted with permanent electrodes in the prefrontal cortex (PFC). The main findings of this study are that: (1) acute MDMA augments locomotor behavior and attenuates the incoming sensory input, (2) chronic treatment of MDMA elicits behavioral sensitization, (3) chronic administration of MDMA results in attenuation of the baseline activity of the sensory evoked field potential, and (4) administration of rechallenge MDMA result in enhancement of the PFC sensory evoked field potential. PMID:19769950

  7. Anterior prefrontal involvement in implicit contextual change detection

    Stefan Pollmann

    2009-10-01

    Full Text Available Anterior prefrontal cortex is usually associated with high level executive functions. Here, we show that the frontal pole, specifically left lateral frontopolar cortex, is involved in signaling change in implicitly learned spatial contexts, in the absence of conscious change detection. In a variant of the contextual cueing paradigm, participants first learned implicitly contingencies between distractor contexts and target locations. After learning, repeated distractor contexts were paired with new target locations. Left lateral frontopolar (BA10 and superior frontal (BA9 cortices showed selective signal increase for this target location change in repeated displays in an event-related fMRI experiment, which was most pronounced in participants with high contextual facilitation before the change. The data support the view that left lateral frontopolar cortex is involved in signaling contextual change to posterior brain areas as a precondition for adaptive changes of attentional resource allocation. This signaling occurs in the absence of awareness of learned contingencies or contextual change.

  8. Behavioral effects of congenital ventromedial prefrontal cortex malformation

    Boes Aaron D

    2011-12-01

    Full Text Available Abstract Background A detailed behavioral profile associated with focal congenital malformation of the ventromedial prefrontal cortex (vmPFC has not been reported previously. Here we describe a 14 year-old boy, B.W., with neurological and psychiatric sequelae stemming from focal cortical malformation of the left vmPFC. Case Presentation B.W.'s behavior has been characterized through extensive review Patience of clinical and personal records along with behavioral and neuropsychological testing. A central feature of the behavioral profile is severe antisocial behavior. He is aggressive, manipulative, and callous; features consistent with psychopathy. Other problems include: egocentricity, impulsivity, hyperactivity, lack of empathy, lack of respect for authority, impaired moral judgment, an inability to plan ahead, and poor frustration tolerance. Conclusions The vmPFC has a profound contribution to the development of human prosocial behavior. B.W. demonstrates how a congenital lesion to this cortical region severely disrupts this process.

  9. Not so "silent":The human prefrontal cortex

    Prakash Narain Tandon

    2013-01-01

    Full Text Available Little was known about the human prefrontal cortex till recently. It was thus labeled as the "silent area," "uncommitted cortex." It not only constitutes the largest component of the human brain but is the latest evolutionary addition to the mammalian brain. It endows the human beings with qualities that differentiate humans from all other animals. During the last couple of decades the advent of modern electrophysiological and imaging (functional magnetic resonance imaging, proton emission tomography, SPECT techniques have provided a wealth of insight into its role in memory, thought, emotions, moral judgment, social behavior, evaluating rewards, and assessing its fairness or otherwise and above all self-awareness. This brief review summarize the recent significant observations on its functions and connectivity which would interest the cognitive scientists and clinicians alike.

  10. Prefrontal Cortical Opioids and Dysregulated Motivation: A Network Hypothesis.

    Baldo, Brian A

    2016-06-01

    Loss of inhibitory control over appetitively motivated behavior occurs in multiple psychiatric disorders, including drug abuse, behavioral addictions, and eating disorders with binge features. In this opinion article, novel actions of μ-opioid peptides in the prefrontal cortex (PFC) that could contribute to inhibitory control deficits will be discussed. Evidence has accrued to suggest that excessive intra-PFC μ-opioid receptor (μ-OR) signaling alters the PFC response to excitatory drive, resulting in supernormal and incoherent recruitment of multiple PFC output pathways. Affected pathways include functionally opposed PFC→hypothalamus 'appetitive driver' and PFC→striatum 'appetitive limiter' projections. This network perturbation engenders disorganized, impulsive appetitive responses. Evidence supporting this hypothesis from human imaging and animal studies will be discussed, and combinatorial drug treatments targeting μ-ORs and specific PFC subcortical targets will be explored. PMID:27233653

  11. The role of prefrontal catecholamines in attention and working memory

    Behrad eNoudoost

    2014-04-01

    Full Text Available While much progress has been made in identifying the brain regions and neurochemical systems involved in the cognitive processes disrupted in mental illnesses, To date, the level of detail at which neurobiologists can describe the chain of events giving rise to cognitive functions is very rudimentary. Much of the intense interest in understanding cognitive functions is motivated by the hope that it might be possible to understand these complex functions at the level of neurons and neural circuits. Here, we review the current state of the literature regarding how modulations in catecholamine levels within the prefrontal cortex alter the neuronal and behavioral correlates of cognitive functions, particularly attention and working memory.

  12. Unilateral Ibotenic Acid Lesions of the Prefrontal Cortex Reduce

    Kuriyama,Shigeki

    2006-12-01

    Full Text Available Rats with 6-hydroxydopamine (6-OHDA-induced lesions of the substantia nigra are used as a model of Parkinson’s disease (PD, and these “lesioned” rats exhibit a rotational behavior when further injected with apomorphine (APO. We examined whether lesions in the prefrontal cortex (PFC could modify the rotational behavior in PD model rats. Rats initially received unilateral lesions of the substantia nigra by 6-OHDA injection, and then their rotational behavior was measured. Two PFC lesions were achieved by intracerebral infusions of ibotenic acid, followed by measurement of APOinduced rotation. Rotation was reduced by approximately 30オ after PFC injury. The PFC may have functional infl uences on the basal ganglia and may be involved in the pathophysiology of the rotational behavior of PD model rats.

  13. Cognitive findings after transient global amnesia: role of prefrontal cortex.

    Le Pira, Francesco; Giuffrida, Salvatore; Maci, Tiziana; Reggio, Ester; Zappalà, Giuseppe; Perciavalle, Vincenzo

    2005-01-01

    The aim of this study is to verify, after recovery, the presence of specific patterns of cognitive dysfunctions in Transient Global Amnesia (TGA). Fourteen patients with the diagnosis of TGA were submitted to a battery of neuropsychological tests and compared to a matched control group. We found significant qualitative and quantitative differences between TGA patients and controls in the California Verbal Learning Test (CLVT) and Rey-Osterrieth Complex Figure Test. Our data support the presence of selective cognitive dysfunctions after the clinical recovery. Moreover, for Verbal Fluency, Digit Span Backward, and Number of Clusters in the CVLT short-term memory test, the relation resulted as positively related with the temporal interval from the TGA episode. Reduction of categorical learning, attention, and qualitative alterations of spatial strategy seem to postulate a planning defect due to a prefrontal impairment. PMID:16422663

  14. The Behavioral Relevance of Task Information in Human Prefrontal Cortex.

    Cole, Michael W; Ito, Takuya; Braver, Todd S

    2016-06-01

    Human lateral prefrontal cortex (LPFC) is thought to play a critical role in enabling cognitive flexibility, particularly when performing novel tasks. However, it remains to be established whether LPFC representation of task-relevant information in such situations actually contributes to successful performance. We utilized pattern classification analyses of functional MRI activity to identify novelty-sensitive brain regions as participants rapidly switched between performance of 64 complex tasks, 60 of which were novel. In three of these novelty-sensitive regions-located within distinct areas of left anterior LPFC-trial-evoked activity patterns discriminated correct from error trials. Further, these regions also contained information regarding the task-relevant decision rule, but only for successfully performed trials. This suggests that left anterior LPFC may be particularly important for representing task information that contributes to the cognitive flexibility needed to perform successfully in novel task situations. PMID:25870233

  15. Reduced Glutamatergic Currents and Dendritic Branching of Layer 5 Pyramidal Cells Contribute to Medial Prefrontal Cortex Deactivation in a Rat Model of Neuropathic Pain

    Kelly, Crystle J.; Huang, Mei; Meltzer, Herbert; Martina, Marco

    2016-01-01

    Multiple studies have demonstrated that neuropathic pain is associated with major reorganization in multiple brain areas. In line with the strong emotional salience of chronic pain, involvement of the limbic system appears particularly important. Within the past few years, it has become clear that the functional deactivation of the prefrontal cortex (PFC) is critical for both the cognitive/emotional and the sensory components of pain. However, at the cellular level, details of this deactivation remain in large part unclear. Here we show that 1 week after a peripheral neuropathic injury (Spared Nerve Injury model) pyramidal cells in layer 5 (L5) of the rat medial PFC show responses to excitatory glutamatergic inputs that are reduced by about 50%, as well as reduced frequency of spontaneous excitatory synaptic currents. Additionally, these cells have reduced membrane capacitance and increased input resistance. All these findings are consistent with decreased dendritic length, thus we performed a detailed morphological analysis on a subset of the recorded neurons. We found that the apical dendrites proximal to the soma (excluding the tuft) are shorter and less complex in SNI animals, in agreement with the reduced capacitance and glutamatergic input. Finally, we used in vivo microdialysis to compare the basal concentrations of glutamate and GABA in the PFC of sham and SNI rats and found that ambient glutamate is decreased in SNI rats. Taken together, these data show that impaired glutamatergic transmission contributes to the functional deactivation of the mPFC in neuropathic pain. Additionally, the reduced branching of apical dendrites of L5 pyramidal neurons may underlay the gray matter reduction in chronic pain.

  16. Use of Chromosome Aberration Frequencies for Biological Dosimetry in Man

    The vast amount of work on chromosome aberrations induced by radiation exposure under defined biological and physical conditions, has shown that there exist strict relationships between aberration frequencies, radiation quality and absorbed dose in a variety of cell systems. These relationships are such that in many irradiated plant and animal systems the frequency of induced chromosome aberrations has been used to give reliable estimates of the radiation dose to which the system was exposed. A similar extrapolation from induced aberration frequency to absorbed dose can be made with human peripheral blood lymphocytes, if such cells are exposed and cultured in vitro under well defined conditions. Moreover, since aberrations induced in lymphocytes following an in vivo exposure can be detected in the cells when subsequently cultured in vitro, the peripheral blood leucocyte system has been utilized for biological dosimetry in cases where individuals have been accidentally exposed to radiations. In the case of uniform whole-body exposure of an individual, and under defined conditions of in vitro culture, the system may be expected to fulfil most of the requirements for a sensitive and accurate biological measure of absorbed dose. In this context biological variations between individuals may be of importance and the influence of such factors as age and genotype on the radiation response are considered. In cases of partial body exposure, there are a variety of biological factors that may have a considerable influence on the yields of aberrations measured in cells removed from the body shortly after exposure. Factors that are important include: the proportions of lymphocytes located in or passing through the radiation field at the time of exposure; the distribution and mobility of lymphocytes between peripheral blood and the lymphoid systems; differences in the radiation response of lymphocytes of differing types, and differences in the capacities of irradiated and non

  17. Altered functional connectivity of the insular cortex across prefrontal networks in cocaine addiction.

    Cisler, Josh M; Elton, Amanda; Kennedy, Ashley P; Young, Jonathan; Smitherman, Sonet; Andrew James, George; Kilts, Clinton D

    2013-07-30

    Interoception is theorized to be an important process mediating substance use disorders, and the insular cortex is recognized as a core neural region supporting interoception. The purpose of this study was to compare the integration of the insular cortex into prefrontal-related resting-state networks between individuals with cocaine dependence and healthy controls. Participants comprised 41 patients with cocaine dependence and 19 controls who underwent a resting-state 3-T functional magnetic resonance imaging scan. Individuals with cocaine dependence demonstrated altered functional connectivity of the insular cortex, predominantly the right insular cortex, with all eight prefrontal-related resting-state networks identified through Independent Component Analysis (ICA). A conjunction analysis demonstrated that the right insular cortex was the neural region with the highest number of common group differences across the networks. There was no evidence that insular cortex connectivity commonly differed between groups for non-prefrontal-related networks. Further, seed-based functional connectivity analyses extended the network analyses and indicated that cocaine dependence was associated with greater connectivity of the right insula with the dorsomedial prefrontal cortex, inferior frontal gyrus, and bilateral dorsolateral prefrontal cortex. These data support the hypothesis that cocaine dependence is related to altered functional interactions of the insular cortex with prefrontal networks. The results suggest possible neural mechanisms by which the insular cortex and interoceptive information influence cognitive control and decision-making processes presumably mediated by prefrontal networks in the cocaine dependence process. PMID:23684980

  18. Faces in the face of death: effects of exposure to life-threatening events and mortality salience on facial expression recognition in combat and noncombat military veterans.

    Anaki, David; Brezniak, Tamar; Shalom, Liron

    2012-08-01

    Soldiers in war zones often experience life-threatening events that put their lives at stake. The present study examined how these exposures shape soldiers' social behavior, manifested by recognition of facial expressions. In addition, we investigated how explicit awareness of one's eventual death affects sensitivity to facial expressions. Veterans of elite military combat units were exposed to conditions of mortality or pain salience and later requested to label the emotions depicted in threatening and nonthreatening faces. Combat veterans were more accurate than noncombat veterans in identifying threatening expressions, both in mortality or pain salience induction (experiment 1) or under no induction at all (experiment 2). In addition, noncombat veterans primed with mortality salience identified fear expressions more accurately than those primed with pain salience. Finally, mortality salience improved accuracy for nonthreatening expressions for all veterans. The present results demonstrate that fear of death, resulting from exposure to concrete life-endangering perils or from thoughts on human's inevitable death, influences perception of facial expressions, which is critical for successful interpersonal communication. PMID:22866887

  19. A study on optical aberrations in parabolic neutron guides

    Wang, Yu; Wang, Hongli; Liu, Yuntao [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China); Zu, Yong [China International Engineering Consulting Corporation, Beijing 100048 (China); He, Linfeng; Wei, Guohai; Sun, Kai [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China); Han, Songbai, E-mail: hansb@ciae.ac.cn [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China); Chen, Dongfeng, E-mail: dongfeng@ciae.ac.cn [Neutron Scattering Laboratory, China Institute of Atomic Energy, Beijing 102413 (China)

    2015-06-21

    It is widely believed that a neutron beam can be focused to a small spot using a parabolic guide, which will significantly improve the flux. However, researchers have also noted challenges for the neutron inhomogeneous phase space distribution in parabolic focusing guide systems. In this paper, the sources of most prominent optical aberrations, such as an inhomogeneous phase space distribution and irregular divergence distribution, are discussed, and an optimization solution is also proposed. We indicate that optimizing the parabolic guide geometrical configuration removes almost all of the aberrations and yields a considerable intensity gain factor.

  20. Aberrations of the point spread function of a multimode fiber

    Descloux, Adrien; Pinkse, Pepijn W H

    2016-01-01

    We investigate the point spread function of a multimode fiber. The distortion of the focal spot created on the fiber output facet is studied for a variety of the parameters. We develop a theoretical model of wavefront shaping through a multimode fiber and use it to confirm our experimental results and analyze the nature of the focal distortions. We show that aberration-free imaging with a large field of view can be achieved by using an appropriate number of segments on the spatial light modulator during the wavefront-shaping procedure. The results describe aberration limits for imaging with multimode fibers as in, e.g., microendoscopy.

  1. Investigation of spherical aberration effects on coherent lidar performance

    Hu, Qi; Rodrigo, Peter John; Iversen, Theis Faber Quist;

    2013-01-01

    different telescope configurations using a hard target. It is experimentally and numerically proven that the SA has a significant impact on lidar antenna efficiency and optimal beam truncation ratio. Furthermore, we demonstrate that both effective probing range and spatial resolution of the system are......In this paper we demonstrate experimentally the performance of a monostatic coherent lidar system under the influence of phase aberrations, especially the typically predominant spherical aberration (SA). The performance is evaluated by probing the spatial weighting function of the lidar system with...

  2. Optical imaging and aberrations, p.2 wave diffraction optics

    Mahajan, Virendra N

    2011-01-01

    Ten years have passed since the publication of the first edition of this classic text in April 2001. Considerable new material amounting to 100 pages has been added in this second edition. Each chapter now contains a Summary section at the end. The new material in Chapter 4 consists of a detailed comparison of Gaussian apodization with a corresponding beam, determination of the optimum value of the Gaussian radius relative to that of the pupil to yield maximum focal-point irradiance, detailed discussion of standard deviation, aberration balancing, and Strehl ratio for primary aberrations, deri

  3. The social modulation of pain: Others as predictive signals of salience – A systematic review

    Charlotte eKrahé

    2013-07-01

    Full Text Available Several studies in cognitive neuroscience have investigated the cognitive and affective modulation of pain. By contrast, fewer studies have focused on the social modulation of pain, despite a plethora of relevant clinical findings. Here we present the first review of experimental studies addressing how interpersonal factors, such as the presence, behaviour and spatial proximity of an observer, modulate pain. Based on a systematic literature search we identified twenty-six studies on experimentally-induced pain that manipulated different interpersonal variables and measured behavioural, physiological and neural pain-related responses. We observed that the modulation of pain by interpersonal factors depended on (1 the degree to which the social partners were active or were perceived by the participants to possess possibility for action; (2 the degree to which participants could perceive the specific intentions of the social partners; (3 the type of pre-existing relationship between the social partner and the person in pain, and lastly, (4 individual differences in relating to others and coping styles. Based on these findings, we propose that the modulation of pain by social factors can be fruitfully understood in relation to a recent predictive coding model, the free energy framework, particularly as applied to interoception and social cognition. Specifically, we argue that interpersonal interactions during pain may function as social, predictive signals of contextual threat or safety and as such influence the salience of noxious stimuli. The perception of such interpersonal interactions may in turn depend on (a prior beliefs about interpersonal relating and (b the certainty or precision by which an interpersonal interaction may predict environmental threat or safety.

  4. The social modulation of pain: others as predictive signals of salience - a systematic review.

    Krahé, Charlotte; Springer, Anne; Weinman, John A; Fotopoulou, Aikaterini

    2013-01-01

    Several studies in cognitive neuroscience have investigated the cognitive and affective modulation of pain. By contrast, fewer studies have focused on the social modulation of pain, despite a plethora of relevant clinical findings. Here we present the first review of experimental studies addressing how interpersonal factors, such as the presence, behavior, and spatial proximity of an observer, modulate pain. Based on a systematic literature search, we identified 26 studies on experimentally induced pain that manipulated different interpersonal variables and measured behavioral, physiological, and neural pain-related responses. We observed that the modulation of pain by interpersonal factors depended on (1) the degree to which the social partners were active or were perceived by the participants to possess possibility for action; (2) the degree to which participants could perceive the specific intentions of the social partners; (3) the type of pre-existing relationship between the social partner and the person in pain, and lastly, (4) individual differences in relating to others and coping styles. Based on these findings, we propose that the modulation of pain by social factors can be fruitfully understood in relation to a recent predictive coding model, the free energy framework, particularly as applied to interoception and social cognition. Specifically, we argue that interpersonal interactions during pain may function as social, predictive signals of contextual threat or safety and as such influence the salience of noxious stimuli. The perception of such interpersonal interactions may in turn depend on (a) prior beliefs about interpersonal relating and (b) the certainty or precision by which an interpersonal interaction may predict environmental threat or safety. PMID:23888136

  5. Aberration of a negative ion beam caused by space charge effect

    Aberrations are inevitable when the charged particle beams are extracted, accelerated, transmitted, and focused with electrostatic and magnetic fields. In this study, we investigate the aberration of a negative ion accelerator for a neutral beam injector theoretically, especially the spherical aberration caused by the negative ion beam expansion due to the space charge effect. The negative ion current density profiles with the spherical aberration are compared with those without the spherical aberration. It is found that the negative ion current density profiles in a log scale are tailed due to the spherical aberration.

  6. Effect of Coma Aberration on Orbital Angular Momentum Spectrum of Vortex Beams

    CHEN Zi-Yang; PU Ji-Xiong

    2009-01-01

    Spiral spectra of vortex beams with coma aberration are studied.It is shown that the orbital angular momentum (OAM) states of vortex beams with coma aberration are different from those aberration-free vortex beams.Spiral spectra of beams with coma aberration are spreading.It is found that in the presence of coma aberration,the vortex beams contain not only the original OAM component but also other components.A larger coma aberration coefficient and/or a larger beam waist will lead to a wider spreading of the spiral spectrum. The results may have potential applications in information encoding and transmittance.

  7. Relationship between wave aberrations and histological features in ex vivo porcine crystalline lenses

    Acosta, Eva; Bueno, Juan M.; Schwarz, Christina; Artal, Pablo

    2010-09-01

    Wave aberrations of isolated ex vivo porcine crystalline lenses were measured by using a point-diffraction interferometer. This method allowed us to gain greater insight into the detailed aberration structure of eye lenses showing systematic presence of some dominant aberrations. In order of significance, astigmatism together with spherical aberration, coma, and trefoil are the main aberrations present in all lenses. We found a high correlation between the axis of both astigmatism and trefoil with the Y-shaped suture planes of the lens, revealing a subtle relationship between the induced aberrations and the histological features.

  8. Sources of Stakeholder Salience in the Responsible Investment Movement: Why Do Investors Sign the Principles for Responsible Investment?

    Majoch, Arleta A. A.; Hoepner, Andreas G. F.; Hebb, Tessa

    2014-01-01

    Since its inception in 2006, the United Nations-backed Principles for Responsible Investment (PRI) have grown to over 1300 signatories representing over $45 trillion. This growth is not slowing down. In this paper, we argue that there is a set of attributes which make the PRI salient as a stakeholder and its claim to sign the six PRI important to institutional investors. We use Mitchell et al.’s (Acad Manag Rev 22:853–886, 1997) theoretical framework of stakeholder salience, as extended by Gi...

  9. Asymmetric Circuit Models and Parameter Measurement for PermanentMagnet Linear Synchronous Motor Considering Inductance Harmonics and Saliency

    Yamamoto, Shu; Yamaguchi, Tomonobu; Hirahara, Hideaki; Ara, Takahiro

    This paper presents asymmetric circuit models and an inductance parameter measurement method for Permanent Magnet Linear Synchronous Motors (PMLSMs). The reason why the tested PMLSM with surface permanent magnet structure exhibits both asymmetry and salient pole natures is investigated. Asymmetric circuit models considering the saliency and inductance harmonic effects are discussed for PMLSM fed by three-phase three-wire power source systems. All fundamental and harmonic inductance parameters are easily determined by a standstill test using a single-phase commercial source. Experimental and simulation results on a single-sided PMLSM with a 3-phase, 4-pole and 14-slot mover demonstrate the validity of the proposed method.

  10. Aberration Corrected Photoemission Electron Microscopy with Photonics Applications

    Fitzgerald, Joseph P. S.

    Photoemission electron microscopy (PEEM) uses photoelectrons excited from material surfaces by incident photons to probe the interaction of light with surfaces with nanometer-scale resolution. The point resolution of PEEM images is strongly limited by spherical and chromatic aberration. Image aberrations primarily originate from the acceleration of photoelectrons and imaging with the objective lens and vary strongly in magnitude with specimen emission characteristics. Spherical and chromatic aberration can be corrected with an electrostatic mirror, and here I develop a triode mirror with hyperbolic geometry that has two adjacent, field-adjustable regions. I present analytic and numerical models of the mirror and show that the optical properties agree to within a few percent. When this mirror is coupled with an electron lens, it can provide a large dynamic range of correction and the coefficients of spherical and chromatic aberration can be varied independently. I report on efforts to realize a triode mirror corrector, including design, characterization, and alignment in our microscope at Portland State University (PSU). PEEM may be used to investigate optically active nanostructures, and we show that photoelectron emission yields can be identified with diffraction, surface plasmons, and dielectric waveguiding. Furthermore, we find that photoelectron micrographs of nanostructured metal and dielectric structures correlate with electromagnetic field calculations. We conclude that photoemission is highly spatially sensitive to the electromagnetic field intensity, allowing the direct visualization of the interaction of light with material surfaces at nanometer scales and over a wide range of incident light frequencies.

  11. Chromosomal aberrations and SCEs as biomarkers of cancer risk

    Norppa, H.; Bonassi, S.; Hansteen, I. L.; Hagmar, L.; Strömberg, U.; Rössner st., Pavel; Boffetta, P.; Lindholm, C.; Gundy, S.; Lazutka, J.; Cebulska-Wasilewska, A.; Fabiánová, E.; Šrám, Radim; Knudsen, L. E.; Barale, R.; Fucic, A.

    2006-01-01

    Roč. 600, - (2006), s. 37-45. ISSN 0027-5107 Institutional research plan: CEZ:AV0Z50390512 Keywords : biomarkers * chromosomal aberration * sister chromatid exchange Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 4.111, year: 2006

  12. Consequences of Aberrant Hedgehog Signaling During Zebrafish Development

    Koudijs, M.J.

    2007-01-01

    The Hedgehog signaling pathway is controlling proliferation, patterning and differentiation during development of vertebrates and invertebrates. Aberrant Hedgehog activity has been shown to be one of the underlying causes of a number of congenital disorders and multiple types of cancer. We investiga

  13. Geometric aberrations in final focussing for heavy ion fusion

    A general formulation is developed to estimate third-order distortions of ion beams without detailed calculations. Several candidate heavy ion fusion (HIF) beams are discussed in detail as examples. Some general ideas on constraints which third-order aberrations place on HIF parameters are developed

  14. Impact of primary aberrations on coherent lidar performance

    Hu, Qi; Rodrigo, Peter John; Iversen, Theis Faber Quist;

    2014-01-01

    demonstration of these tendencies. Furthermore, our numerical and experimental results show good agreement. We also demonstrate how the truncation of the transmit beam affects the system performance. It is both experimentally and numerically proven that aberration effects have profound impact on the antenna...

  15. Chromosomal aberration frequency in lymphocytes predicts the risk of cancer

    Bonassi, Stefano; Norppa, Hannu; Ceppi, Marcello;

    2008-01-01

    Mechanistic evidence linking chromosomal aberration (CA) to early stages of cancer has been recently supported by the results of epidemiological studies that associated CA frequency in peripheral lymphocytes of healthy individuals to future cancer incidence. To overcome the limitations of single...

  16. Frequency and distribution studies of asymmetrical versus symmetrical chromosome aberrations

    Two aspects of the relationship between Asymmetrical (A) and Symmetrical (S) radiation-induced chromosomal aberrations are considered in this paper. (1) Are A and S truly alternative modes of lesion interaction. Relative frequencies for chromatid-type and chromosome-type are examined, and new lymphocyte data using banding is used to look at this, and also for parallelism in chromosome participation of the two forms for various aberration categories. All the tests applied suggest that A and S are alternative interaction modes. (2) The long-term survival characteristics of A and S are discussed, and the differences in expected frequencies of derived S per surviving cell from chromosome-type and chromatid-types are stressed. Since many in vivo tissues have varying mixtures of potential chromatid and chromosome aberration-bearing target cells, ultimate cell survival and derived S frequencies may differ between tissues for the same absorbed dose. An Appendix gives Relative Corrected Lengths (RCL) for chromosomes of the human karyotype which should be used when testing the various exchange aberration categories for random chromosome participation. (orig.)

  17. Telomere Length in Circulating Lymphocytes: Association with Chromosomal Aberrations

    Hemminki, K.; Rachakonda, S.; Musak, L.; Vymetálková, Veronika; Halasová, E.; Forsti,, A.; Vodičková, Ludmila; Buchancová, J.; Vodička, Pavel; Kumar, R.

    2015-01-01

    Roč. 54, č. 3 (2015), s. 194-196. ISSN 1045-2257 Institutional support: RVO:68378041 Keywords : structural chromosome aberrations * healthy subjects * relative telomere length * genotoxicity * telomere biology Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.041, year: 2014

  18. Chromosomal aberrations in tire plant workers and interaction with

    Musak, L.; Souček, P.; Vodičková, Ludmila; Naccarati, Alessio; Halasová, E.; Poláková, Veronika; Slyšková, Jana; Susová, S.; Buchancová, J.; Šmerhovský, Z.; Sediková, J.; Klimentová, G.; Osina, O.; Hemminki, K.; Vodička, Pavel

    2008-01-01

    Roč. 641, 1-2 (2008), s. 36-42. ISSN 0027-5107 R&D Projects: GA MZd NR8563 Institutional research plan: CEZ:AV0Z50390512 Keywords : Chromosomal aberrations * Genetic polymorphisms * DNA repair genes Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.198, year: 2008

  19. Chromosome aberrations induced in human lymphocytes by neutron irradiation

    In vitro dose-response curves of unstable chromosome aberrations in human lymphocytes have been obtained for neutron spectra of mean energies 0.7, 0.9, 7.6 and 14.7 MeV. The aberration yields have been fitted to the quadratic function Y = αD + βD2, which is consistent with the single-track and two-track model of aberration formation. However with high-LET radiation, the linear component of yield, corresponding to damage caused by single tracks, predominates, and this term becomes more dominant with increasing LET, so that for fission spectrum neutrons the relationship is linear, Y = αD. At low doses, such as those received by radiation workers, limiting r.b.e. values between 13 and 47 were obtained relative to 60Co γ-radiation. At higher doses, as used in radiotherapy, the values were much lower; ranging from 2.7 to 8 at 200 rad of equivalent γ-radiation. Both sets of r.b.e. values correlated well with track-averaged LET but not with dose-averaged LET. When the numbers of cells without aberrations were plotted against radiation dose, curves were obtained which are similar in shape to those for conventional cell-survival experiments with comparable neutron spectra. The D0 values obtained in the present study are close to those from other cell systems. (author)

  20. Frequency of primary amenorrhea due to chromosomal aberration

    Objective: To find out the frequency of primary amenorrhea due to chromosomal aberration and the different options available for management. Subjects and Methods: All patients with primary amenorrhea due to chromosomal aberrations were included in study. Patient's detailed history, general physical examination, presence or absence of secondary sexual characteristics, abdominal and pelvic examination finding were noted. Targeted investigations, including ultrasound, hormonal assay, buccal smear and karyotyping results were recorded. The management options were individually tailored with focus n psychological management. Results: Eighteen patients out of 30,000 patients were diagnosed as having primary amenorrhea. Six had primary amenorrhea due to chromosomal aberrations with the frequency of 0.02%. The age at presentation was 20 years and above in 50%. The most common cause was Turner's syndrome seen in 4 out of 6. The presenting symptoms were delay in onset of menstruation in 05 patients and primary infertility in 01 patient. Conclusion: Primary amenorrhea due to chromosomal aberration is an uncommon condition requiring an early and accurate diagnosis. Turner's syndrome is a relatively common cause of this condition. Management should be multi-disciplinary and individualized according to the patient's age and symptom at presentation. Psychological management is very important and counselling throughout treatment is recommended. (author)

  1. Oxidative stress and chromosomal aberrations in an environmentally exposed population

    Rössner ml., Pavel; Rössnerová, Andrea; Šrám, Radim

    2011-01-01

    Roč. 707, 1-2 (2011), s. 34-41. ISSN 0027-5107 R&D Projects: GA MŽP(CZ) SP/1B3/8/08 Institutional research plan: CEZ:AV0Z50390512 Keywords : air pollution * oxidative stress * chromosomal aberrations Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.850, year: 2011

  2. Radiation induced chromosomal aberrations after cardiac catheterization and angiocardiography

    The relationship between the radiation doses and the chromosomal aberrations of peripheral lymphocytes was studied in patients under-going catheterization with or without angiocardiography. The radiation doses were estimated and chromosomal aberration analyses were carried out in 17 cases. They consisted of 10 males and 7 females at the age of 4 to 26 years with an average of 14 years. Doses in the chest and gonadal regions were measured with calibrated thermoluminescent dosimeters. Peripheral blood samples were taken immediately before and after the diagnostic procedure for chromosome analyses. Results showed that the average doses in the gonad region during cardiac catheterization with and without angiocardiography were 2.4 and 0.83 kC/kg respectively, while those in the chest region were as high as 0.93 and 0.54 kC/kg respectively. The chromosome aberration rate in both groups were significantly higher (2.75-3.33%) than the control value (0.22-0.75%) which was determined before X ray examination. No statistically significant difference of chromosome aberration yield was found between the two groups with and without angiocardiography

  3. Active Optical Control of Quasi-Static Aberrations for ATST

    Johnson, L. C.; Upton, R.; Rimmele, T. R.; Hubbard, R.; Barden, S. C.

    2012-12-01

    The Advanced Technology Solar Telescope (ATST) requires active control of quasi-static telescope aberrations in order to achieve the image quality set by its science requirements. Four active mirrors will be used to compensate for optical misalignments induced by changing gravitational forces and thermal gradients. These misalignments manifest themselves primarily as low-order wavefront aberrations that will be measured by a Shack-Hartmann wavefront sensor. When operating in closed-loop with the wavefront sensor, the active optics control algorithm uses a linear least-squares reconstructor incorporating force constraints to limit force applied to the primary mirror while also incorporating a neutral-point constraint on the secondary mirror to limit pointing errors. The resulting system compensates for astigmatism and defocus with rigid-body motion of the secondary mirror and higher-order aberrations with primary mirror bending modes. We demonstrate this reconstruction method and present simulation results that apply the active optics correction to aberrations generated by finite-element modeling of thermal and gravitational effects over a typical day of ATST operation. Quasi-static wavefront errors are corrected to within limits set by wavefront sensor noise in all cases with very little force applied to the primary mirror surface and minimal pointing correction needed.

  4. Frequency of chromosomal aberrations in Prague mothers and their newborns.

    Rössnerová, Andrea; Balascak, I.; Rössner ml., Pavel; Šrám, Radim

    2010-01-01

    Roč. 699, 1-2 (2010), s. 29-34. ISSN 1383-5718 R&D Projects: GA MŠk 2B06088 Institutional research plan: CEZ:AV0Z50390512 Keywords : Carcinogenic polycyclic aromatic hydrocarbons * Chromosomal aberrations * Fluorescence in situ hybridization Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.938, year: 2010

  5. Long-term persistence of chromosome aberrations in uranium miners.

    Mészáros, Gabriella; Bognár, Gabriella; Köteles, G J

    2004-07-01

    Chromosome aberration analyses were performed on blood samples from 165 active underground uranium miners between 1981 and 1985. After decommissioning the mine in 1997 chromosome aberration analyses were also included in the medical laboratory investigations of health conditions of 141 subjects between 1998 and 2002 within the framework of a follow-up-study. The numerical data are presented as functions of the exposure categories expressed in working level month up to 600. In the active groups the dicentric level was 7 to 12 times higher than in the unexposed population, the acentrics also higher with more than an order of magnitude, the frequency of total aberrations--including dicentrics, acentrics, rings, deletions, minits and numerical aberrations, i.e. both chromatid and chromosome type of aberrations were also well above the control level. In the group of former uranium miners although there were slight decreases in the dicentrics after 8 to 25 yr, the values were not significantly different from the values of active miners. The frequency of deletions was also maintained in the post-mining period. The frequency of acentrics, however, decreased significantly, but even the lowest values remained 2-3 times higher than the values in the unexposed population.The possibility is suggested that for the long-term persistence of cytogenetic alterations the permanent production and presence of clastogenic factors might be responsible. The comparison of the two datasets suggest a long-term persistence of cytogenetic alterations above the population average values in a large fraction of persons investigated. PMID:15308832

  6. Chromatin structure and ionizing-radiation-induced chromosome aberrations

    The possible influence of chromatic structure or activity on chromosomal radiosensitivity was studied. A cell line was isolated which contained some 105 copies of an amplified plasmid in a single large mosquito artificial chromosome (MAC). This chromosome was hypersensitive to DNase I. Its radiosensitivity was some three fold greater than normal mosquito chromosomes in the same cell. In cultured human cells irradiated during G0, the initial breakage frequency in chromosome 4, 19 and the euchromatic and heterochromatic portions of the Y chromosome were measured over a wide range of doses by inducing Premature Chromosome Condensation (PCC) immediately after irradiation with Cs-137 gamma rays. No evidence was seen that Y heterochromatin or large fragments of it remained unbroken. The only significant deviation from the expected initial breakage frequency per Gy per unit length of chromosome was that observed for the euchromatic portion of the Y chromosome, with breakage nearly twice that expected. The development of aberrations involving X and Y chromosomes at the first mitosis after irradation was also studied. Normal female cells sustained about twice the frequency of aberrations involving X chromosomes for a dose of 7.3 Gy than the corresponding male cells. Fibroblasts from individuals with supernumerary X chromosomes did not show any further increase in X aberrations for this dos. The frequency of aberrations involving the heterochromatic portion of the long arm of the Y chromosome was about what would be expected for a similar length of autosome, but the euchromatic portion of the Y was about 3 times more radiosensitive per unit length. 5-Azacytidine treatment of cultured human female fibroblasts or fibroblasts from a 49,XXXXY individual, reduced the methylation of cytosine residues in DNA, and resulted in an increased chromosomal radiosensitivity in general, but it did not increase the frequency of aberrations involving the X chromosomes

  7. Non-Gaussianity and CMB aberration and Doppler

    The peculiar motion of an observer with respect to the CMB rest frame induces a deflection in the arrival direction of the observed photons (also known as CMB aberration) and a Doppler shift in the measured photon frequencies. As a consequence, aberration and Doppler effects induce non trivial correlations between the harmonic coefficients of the observed CMB temperature maps. In this paper we investigate whether these correlations generate a bias on non-Gaussianity estimators fNL. We perform this analysis simulating a large number of temperature maps with Planck-like resolution (lmax = 2000) as different realizations of the same cosmological fiducial model (WMAP7yr). We then add to these maps aberration and Doppler effects employing a modified version of the HEALPix code. We finally evaluate a generalization of the Komatsu, Spergel and Wandelt non-Gaussianity estimator for all the simulated maps, both when peculiar velocity effects have been considered and when these phenomena have been neglected. Using the value v/c = 1.23 × 10−3 for our peculiar velocity, we found that the aberration/Doppler induced non-Gaussian signal is at most of about half of the cosmic variance σ for fNL both in a full-sky and in a cut-sky experimental configuration, for local, equilateral and orthogonal estimators. We conclude therefore that when estimating fNL it is safe to ignore aberration and Doppler effects if the primordial map is already Gaussian. More work is necessary however to assess whether a map which contains non-Gaussianity can be significantly distorted by a peculiar velocity

  8. Antipsychotic medication and prefrontal cortex activation : A review of neuroimaging findings

    Liemburg, Edith J.; Knegtering, Henderikus; Klein, Hans C.; Kortekaas, Rudie; Aleman, Andre

    2012-01-01

    Decreased prefrontal activation (hypofrontality) in schizophrenia is thought to underlie negative symptoms and cognitive impairments, and may contribute to poor social outcome. Hypofrontality does not always improve during treatment with antipsychotics. We hypothesized that antipsychotics, which sha

  9. Familial Vulnerability to ADHD Affects Activity in the Cerebellum in Addition to the Prefrontal Systems

    Mulder, Martijn J.; Baeyens, Dieter; Davidson, Matthew C.; Casey, B. J.; Van Den Ban, Els; Van Engeland, Herman; Durston, Sarah

    2008-01-01

    The study examines whether cerebellar systems are sensitive to familial risk for ADHD in addition to frontostriatal circuitry. The results conclude that familial vulnerability to ADHD affects activity in both the prefrontal cortex and cerebellum.

  10. Reducing the Harm of Stress: Medications to Rescue the Prefrontal Cortex and Overcome Bad Habits

    Jin, Lu E.

    2011-01-01

    Our brain is sensitive to stress. Both acute and chronic stress cause cognitive deficits and induce chronic disorders such as drug addiction. In a June 2011 conference at Yale entitled “The Science of Stress: Focus on the Brain, Breaking Bad Habits, and Chronic Disease,” Drs. Amy Arnsten and Sherry Mckee discussed the roles of prefrontal cortex in the treatment of stress impairments and addiction. Medications to strengthen the prefrontal function, such as prazosin and guanfacine, may reduce t...

  11. Evidence for reduced experience-dependent dendritic spine plasticity in the aging prefrontal cortex

    Bloss, Erik B.; Janssen, William G.; Ohm, Daniel T.; Yuk, Frank J; Wadsworth, Shannon; Saardi, Karl M.; Bruce S McEwen; Morrison, John H.

    2011-01-01

    Cognitive functions that require the prefrontal cortex are highly sensitive to aging in humans, non-human primates, and rodents, although the neurobiological correlates of this vulnerability remain largely unknown. It has been proposed that dendritic spines represent the primary site of structural plasticity in the adult brain, and recent data have supported the hypothesis that aging is associated with alterations of dendritic spine morphology and plasticity in prefrontal cortex. However, no ...

  12. Interactive effects of stress and aging on structural plasticity in the prefrontal cortex

    Bloss, Erik B.; Janssen, William G.; Bruce S McEwen; Morrison, John H.

    2010-01-01

    Neuronal networks in the prefrontal cortex mediate the highest levels of cognitive processing and decision making, and the capacity to perform these functions is among the cognitive features most vulnerable to aging. Despite much research, the neurobiological basis of age-related compromised prefrontal function remains elusive. Many investigators have hypothesized that exposure to stress may accelerate cognitive aging, though few studies have directly tested this hypothesis and even fewer hav...

  13. High familial risk for mood disorder is associated with low dorsolateral prefrontal cortex serotonin transporter binding

    Frokjaer, Vibe G; Vinberg, Maj; Erritzoe, David;

    2009-01-01

    Mood disorders are elicited through a combination of genetic and environmental stress factors, and treatment with selective serotonin reuptake inhibitors ameliorates depressive symptoms. Changes in the serotonin transporter (SERT) binding may therefore occur in depressive patients and in subjects...... measured with [(11)C]DASB PET. The volumes of interest included the orbitofrontal cortex, the dorsolateral prefrontal cortex, the ventrolateral prefrontal cortex, anterior cingulate, caudate, putamen, thalamus, and midbrain. We found that individuals at high familial risk for mood disorders had a 35...

  14. A model of amygdala-hippocampal-prefrontal interaction in fear conditioning and extinction in animals

    Moustafa, Ahmed A.; Gilbertson, Mark W.; Orr, Scott P.; Herzallah, Mohammad M.; Servatius, Richard J.; Myers, Catherine E.

    2012-01-01

    Empirical research has shown that the amygdala, hippocampus, and ventromedial prefrontal cortex (vmPFC) are involved in fear conditioning. However, the functional contribution of each brain area and the nature of their interactions are not clearly understood. Here, we extend existing neural network models of the functional roles of the hippocampus in classical conditioning to include interactions with the amygdala and prefrontal cortex. We apply the model to fear conditioning, in which animal...

  15. Impaired Error-Likelihood Prediction in Medial Prefrontal Cortex in Schizophrenia

    Krawitz, Adam; Braver, Todd S.; Barch, Deanna M.; Brown, Joshua W.

    2010-01-01

    The cognitive impairment in individuals with schizophrenia includes deficits of working memory in dorsolateral prefrontal cortex and deficits of performance monitoring in medial prefrontal cortex (MPFC). Recent work suggests a more general role for MPFC in predicting the outcome of actions and then evaluating those predictions. Here we investigate, in individuals with schizophrenia, two specific effects associated with this role: the error likelihood effect (occurring on trials with correct p...

  16. Depressed Mood and Lateralized Prefrontal Activity During a Stroop Task in Adolescent Children

    Killgore, William D.S.; Gruber, Staci A.; Yurgelun-Todd, Deborah A.

    2007-01-01

    Negative affective style and depressive disorders share a common pattern of brain activation asymmetry in adults, characterized by reduced left relative to right prefrontal activation. It is not clear whether a similar pattern of asymmetry is related to depressive mood state during the period of adolescence, an important stage of emotional and brain development. We correlated Beck Depression Inventory (BDI) scores from 16 adolescents with prefrontal, anterior cingulate, and amygdala activity ...

  17. Increased oxygenation of the cerebral prefrontal cortex prior to the onset of voluntary exercise in humans.

    Matsukawa, Kanji; Ishii, Kei; Liang, Nan; Endo, Kana; Ohtani, Ryo; Nakamoto, Tomoko; Wakasugi, Rie; Kadowaki, Akito; Komine, Hidehiko

    2015-09-01

    To determine whether output from the forebrain (termed central command) may descend early enough to increase cardiac and renal sympathetic outflows at the onset of voluntary exercise, we examined the changes in regional tissue blood flows of bilateral prefrontal cortices with near-infrared spectroscopy, precisely identifying the onset of voluntary ergometer 30-s exercise at 41 ± 2% of the maximal exercise intensity in humans. Prefrontal oxygenated-hemoglobin (Oxy-Hb) concentration was measured as index of regional blood flow unless deoxygenated-hemoglobin concentration remained unchanged. Prefrontal Oxy-Hb concentration increased significantly (P start, whereas such increase in prefrontal Oxy-Hb was absent before exercise abruptly started by a verbal cue. Furthermore, the increase in prefrontal Oxy-Hb observed at the initial 15-s period of exercise was greater with arbitrary start than cued start. The prefrontal Oxy-Hb, thereafter, decreased during the later period of exercise, irrespective of either arbitrary or cued start. The reduction in prefrontal Oxy-Hb had the same time course and response magnitude as that during motor-driven passive exercise. Cardiac output increased at the initial period of exercise, whereas arterial blood pressure and total peripheral resistance decreased. The depressor response was more pronounced (P start than cued start. Taken together, it is suggested that the increase in prefrontal Oxy-Hb observed prior to the onset of voluntary exercise may be in association with central command, while the later decrease in the Oxy-Hb during exercise may be in association with feedback stimulated by mechanical limb motion. PMID:26183481

  18. Sexual dimorphism and laterality in the evolution of the primate prefrontal cortex

    Smaers, J. B.; Mulvaney, P.I.; Soligo, C.I.; Zilles, K.; Amunts, K.

    2012-01-01

    Social selective pressures are commonly considered as the main driving force of primate brain evolution. Primate social behaviour is, however, known to be sexually dimorphic, and no previous study has made a direct comparison between male and female brain structures across species. We quantify sex-specific evolutionary trends in the prefrontal cortex of anthropoid primates (including humans) to investigate how sexual selection has shaped brain evolution in primates. The prefrontal cortex is o...

  19. The hippocampal-prefrontal pathway: the weak link in psychiatric disorders?

    Godsil, Bill,; Kiss, Janos,; Spedding, Michael; Jay, Thérèse

    2013-01-01

    International audience While the hippocampal formation and the prefrontal cortex each have a well-established role in cognitive and mnemonic processes, the extent and manner in which these structures interact to achieve these functions has not been fully delineated. Recent research in rodents compellingly supports the idea that the projection of neurons extending from the CA1 region of the hippocampus and from the subiculum to the prefrontal cortex, referred to here as the H-PFC pathway, i...

  20. Development of abstract thinking during childhood and adolescence: The role of rostrolateral prefrontal cortex

    Iroise Dumontheil

    2014-01-01

    Rostral prefrontal cortex (RPFC) has increased in size and changed in terms of its cellular organisation during primate evolution. In parallel emerged the ability to detach oneself from the immediate environment to process abstract thoughts and solve problems and to understand other individuals’ thoughts and intentions. Rostrolateral prefrontal cortex (RLPFC) is thought to play an important role in supporting the integration of abstract, often self-generated, thoughts. Thoughts can be tempora...