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Emotional Stimuli (emotional + stimulus)
Selected AbstractsBrain mechanisms underlying emotional alterations in the peripartum period in ratsDEPRESSION AND ANXIETY, Issue 3 2003Inga D. Neumann Abstract In the period before and after parturition, i.e., in pregnancy and lactation, a variety of neuroendocrine alterations occur that are accompanied by marked behavioral changes, including emotional responsiveness to external challenging situations. On the one hand, activation of neuroendocrine systems (oxytocin, prolactin) ensures reproduction-related physiological processes, but in a synergistic manner also ensures accompanying behaviors necessary for the survival of the offspring. On the other hand, there is a dramatic reduction in the responsiveness of neuroendocrine systems to stimuli not relevant for reproduction, such as the hypothalamo-pituitary-adrenal (HPA) axis responses to physical or emotional stimuli in both pregnant and lactating rats. With CRH being the main regulator of the HPA axis, downregulation of the brain CRH system may result in various behavioral, in particular emotional, adaptations of the maternal organisms, including changes in anxiety-related behavior. In support of this, the lactating rat becomes less emotionally responsive to novel situations, demonstrating reduced anxiety, and shows a higher degree of aggressive behavior in the test for agonistic behavior as well as in the maternal defense test. These changes in emotionality are independent of the innate (pre-lactation) level of anxiety and are seen in both rats bred for high as well as low levels of anxiety. Both brain oxytocin and prolactin, highly activated at this time, play a significant role in these behavioral and possibly also neuroendocrine adaptations in the peripartum period. Depression and Anxiety 17:111,121, 2003. © 2003 Wiley-Liss, Inc. [source] Increased right amygdala volume in lithium-treated patients with bipolar I disorderACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2010J. Usher Usher J, Menzel P, Schneider-Axmann T, Kemmer C, Reith W, Falkai P, Gruber O, Scherk H. Increased right amygdala volume in lithium-treated patients with bipolar I disorder. Objective:, The amygdala plays a major role in processing emotional stimuli. Fourteen studies using structural magnetic resonance imaging (MRI) have examined the amygdala volume in paediatric and adult patients with bipolar disorder (BD) compared with healthy controls (HC) and reported inconsistent findings. Lithium has been found to increase grey matter volume, and first evidence points towards an effect on regional brain volume such as the amygdala. Method:, We examined the amygdala volume of euthymic patients with BD treated with lithium (n = 15), without lithium (n = 24) and HC (n = 41) using structural MRI. Results:, Patients treated with lithium exhibited in comparison to HC a larger right absolute (+17.9%, P = 0.015) and relative (+18%, P = 0.017) amygdala volume. There was no significant difference in amygdala volume between patients without lithium treatment and HC. Conclusion:, Lithium appears to have a sustained effect on a central core region of emotional processing and should therefore be considered in studies examining BD. [source] Serotonergic genes modulate amygdala activity in major depressionGENES, BRAIN AND BEHAVIOR, Issue 7 2007U. Dannlowski Serotonergic genes have been implicated in the pathogenesis of depression probably via their influence on neural activity during emotion processing. This study used an imaging genomics approach to investigate amygdala activity in major depression as a function of common functional polymorphisms in the serotonin transporter gene (5-HTTLPR) and the serotonin receptor 1A gene (5-HT1A -1019C/G). In 27 medicated patients with major depression, amygdala responses to happy, sad and angry faces were assessed using functional magnetic resonance imaging at 3 Tesla. Patients were genotyped for the 5-HT1A -1019C/G and the 5-HTTLPR polymorphism, including the newly described 5-HTT-rs25531 single nucleotide polymorphism. Risk allele carriers for either gene showed significantly increased bilateral amygdala activation in response to emotional stimuli, implicating an additive effect of both genotypes. Our data suggest that the genetic susceptibility for major depression might be transported via dysfunctional neural activity in brain regions critical for emotion processing. [source] Increased self-focus in major depressive disorder is related to neural abnormalities in subcortical-cortical midline structuresHUMAN BRAIN MAPPING, Issue 8 2009Simone Grimm Abstract Patients with major depressive disorder (MDD) often show a tendency to strongly introspect and reflect upon their self, which has been described as increased self-focus. Although subcortical-cortical midline structures have been associated with reflection and introspection of oneself in healthy subjects, the neural correlates of the abnormally increased attribution of negative emotions to oneself, i.e. negative self-attribution, as hallmark of the increased self-focus in MDD remain unclear. The aim of the study was, therefore, to investigate the neural correlates during judgment of self-relatedness of positive and negative emotional stimuli thereby testing for emotional self-attribution. Using fMRI, we investigated 27 acute MDD patients and compared them with 25 healthy subjects employing a paradigm that focused on judgment of self-relatedness when compared with mere perception of the very same emotional stimuli. Behaviourally, patients with MDD showed significantly higher degrees of self-relatedness of specifically negative emotional stimuli when compared with healthy subjects. Neurally, patients with MDD showed significantly lower signal intensities in various subcortical and cortical midline regions like the dorsomedial prefrontal cortex (DMPFC), supragenual anterior cingulate cortex, precuneus, ventral striatum (VS), and the dorsomedial thalamus (DMT). Signal changes in the DMPFC correlated with depression severity and hopelessness whereas those in the VS and the DMT were related to judgment of self-relatedness of negative emotional stimuli. In conclusion, we present first evidence that the abnormally increased negative self-attribution as hallmark of the increased self-focus in MDD might be mediated by altered neural activity in subcortical-cortical midline structures. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [source] Differential parametric modulation of self-relatedness and emotions in different brain regionsHUMAN BRAIN MAPPING, Issue 2 2009Georg Northoff Abstract Our sense of self is strongly colored by emotions although at the same time we are well able to distinguish affect and self. Using functional magnetic resonance imaging, we here tested for the differential effects of self-relatedness and emotion dimensions (valence, intensity) on parametric modulation of neural activity during perception of emotional stimuli. We observed opposite parametric modulation of self-relatedness and emotion dimensions in the dorsomedial prefrontal cortex and the ventral striatum/nucleus accumbens, whereas neural activity in subcortical regions (tectum, right amygdala, hypothalamus) was modulated by self-relatedness and emotion dimensions in the same direction. In sum, our results demonstrate that self-relatedness is closely linked to emotion dimensions of valence and intensity in many lower subcortical brain regions involved in basic emotional systems and, at the same time, distinct from them in higher cortical regions that mediate cognitive processes necessary for becoming aware of one's self, for example self-consciousness. Hum Brain Mapp, 2009. © 2007 Wiley-Liss, Inc. [source] Posterior cingulate activation during moral dilemma in adolescentsHUMAN BRAIN MAPPING, Issue 8 2008Jesus Pujol Abstract Neuroimaging research examining correlates of adolescent behavioral maturation has focused largely on issues related to higher cognitive development. Currently few studies have explored neural correlates of emotional reactivity in adolescent groups. In this study, we sought to examine the nature of posterior cingulate activation during situations of moral dilemma in normal adolescents. We focused on this region because of emerging evidence that suggests its role in emotionally self-relevant mental processing. Ten healthy teenagers, aged from 14 to 16 years, underwent three fMRI sequences designed to examine (i) brain responses during moral dilemma; (ii) brain responses during passive viewing of the moral dilemma outcome; and (iii); "deactivation" during a simple cognitive task compared with resting-state activity. Our main finding was that during moral dilemma, all subjects showed significant activation of the posterior cingulate cortex, and more variable activation of the medial frontal cortex and angular gyrus. Interestingly, these findings were replicated in each subject using the passive viewing task, suggesting that the previous pattern was not specific to moral reasoning or decision making. Finally, six of the ten subjects showed deactivation of the same posterior cingulate region during the cognitive task, indicating some commonality of function between posterior cingulate activity during moral dilemmas and rest. We propose that these posterior cingulate changes may relate to basic neuronal activities associated with processing self-relevant emotional stimuli. Given the high single-subject reproducibility of posterior cingulate activations, our findings may contribute to further characterize adolescent emotional reactivity in developmental neuroimaging studies. Hum Brain Mapp, 2008. © 2007 Wiley-Liss, Inc. [source] Enhancement of activity of the primary visual cortex during processing of emotional stimuli as measured with event-related functional near-infrared spectroscopy and event-related potentialsHUMAN BRAIN MAPPING, Issue 1 2008Martin J. Herrmann Abstract In this study we investigated whether event-related near-infrared spectroscopy (NIRS) is suitable to measure changes in brain activation of the occipital cortex modulated by the emotional content of the visual stimuli. As we found in a previous pilot study that only positive but not negative stimuli differ from neutral stimuli (with respect to oxygenated haemoglobin), we now measured the event-related EEG potentials and NIRS simultaneously during the same session. Thereby, we could evaluate whether the subjects (n = 16) processed the positive as well as the negative emotional stimuli in a similar way. During the task, the subjects passively viewed positive, negative, and neutral emotional pictures (40 presentations were shown in each category, and pictures were taken from the International Affective Picture System, IAPS). The stimuli were presented for 3 s in a randomized order (with a mean of 3 s interstimulus interval). During the task, we measured the event-related EEG potentials over the electrode positions O1, Oz, O2, and Pz and the changes of oxygenated and deoxygenated haemoglobin by multichannel NIRS over the occipital cortex. The EEG results clearly show an increased early posterior negativity over the occipital cortex for both positive as well as negative stimuli compared to neutral. The results for the NIRS measurement were less clear. Although positive as well as negative stimuli lead to significantly higher decrease in deoxygenated haemoglobin than neutral stimuli, this was not found for the oxygenated haemoglobin. Hum Brain Mapp 29:28,35, 2008. © 2007 Wiley-Liss, Inc. [source] Processing of emotionally toned pictures in dementiaINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 9 2006P. A. T. M. Eling Abstract Background Apathy is a common symptom in dementia and is often associated with reduced emotional reactivity. This study examined whether reduced emotional reactivity can be demonstrated in dementia patients using a picture viewing task. Methods The viewing time of three different types of visual stimuli was measured in 24 elderly participants, half of which suffered from dementia. The participants had to make a target response to an emotionally neutral target stimulus that was intermixed with a frequently occurring non-target or ,background' stimulus and infrequently presented emotional stimuli. All participants could control the presentation time of each stimulus, but one half of the participants were explicitly instructed to perform the task quickly. Results The main measure was a ratio score in which the viewing time for emotional stimuli was expressed relative to the viewing time for the neutral non-target stimulus. Using this measure, the instigation of a time-pressure condition proved to significantly reduce the viewing time for emotional stimuli in the healthy subjects. Irrespective of time-pressure condition, the dementia patients showed a similar short viewing time for emotional stimuli as did the healthy subjects in the time-pressure condition. However, both dementia patients and healthy controls displayed longer viewing times for unpleasant than for pleasant stimuli. Conclusion These results suggest the ability of the present task to reveal the simultaneous occurrence of an overall reduced interest for novel stimuli and an intact differential emotional reactivity to stimuli with a negative versus positive valence in the dementia patients. Copyright © 2006 John Wiley & Sons, Ltd. [source] Emotional arousal and gender differences in aggression: A meta-analysisAGGRESSIVE BEHAVIOR, Issue 5 2002George P. Knight Abstract This meta-analysis investigated the possibility that gender differences in aggression, and the variability in these differences, are a function of gender differences in the regulation of arousal generated in emotionally evocative contexts. The sample of studies for this analysis was based on an exhaustive search of the relevant research reports from 1965,1999. Studies were excluded from the sample if they were case studies; investigated spousal/familial or societal violence, war, suicide, or political violence; involved clinical or deviant participants; included fewer than 10 participants; included all male, all female, all non-Caucasian, or non-US/non-Canadian participants. Based on previous evidence that males may be more easily aroused by aggressive-relevant emotional stimuli than females, and that males may have more difficulty regulating emotionally arousing states than females, we hypothesized that the magnitude of the gender differences in aggression would covary, in a nonlinear manner, with the emotional evocativeness of the study context. Consistent with our hypothesis, the magnitude of gender differences in aggression was relatively small in research contexts that appeared to produce no or large increments in emotional arousal and larger (favoring males) in contexts that appeared to produce small or medium increments in emotional arousal. Aggr. Behav. 28:366,393, 2002. © 2002 Wiley-Liss, Inc. [source] Blunted Rostral Anterior Cingulate Response During a Simplified Decoding Task of Negative Emotional Facial Expressions in Alcoholic PatientsALCOHOLISM, Issue 9 2007Jasmin B. Salloum Background:, Alcoholism is characterized by deficits in emotional functioning as well as by deficits in cognitive functioning. However, most brain imaging research on alcoholism has focused on cognition rather than emotion. Method:, We used an event-related functional magnetic imaging approach to examine alcoholics' brain blood oxygenation level dependent (BOLD) response to evaluation of emotional stimuli and to compare their response to that of nonalcoholic controls. The task used was a simplified variant of a facial emotion-decoding task in which subjects determined the intensity level of a target emotion displayed as a facial expression. Facial expressions of happy, sad, anger, disgust, and fear were used as stimuli. Results:, Alcoholics and controls did not differ in accurately identifying the intensity level on the simple emotional decoding task but there were significant differences in their BOLD response during evaluation of facial emotion. In general, alcoholics showed less brain activation than nonalcoholic controls. The greatest differences in activation were during decoding of facial expressions of fear and disgust during which alcoholics had significantly less activation than controls in the affective division of the anterior cingulate cortex (ACC). Alcoholics also had significantly less activation than controls in the affective division of the ACC, while viewing sad faces. Only to facial expressions of anger did the alcoholics show significant activation in the affective ACC and in this case, their BOLD response did not significantly differ from that of the controls. Conclusion:, Alcoholics show a deficit in the function of the affective division of the ACC during evaluation of negative facial emotions that can serve as cues for flight or avoidance. This deficit may underlie some of the behavioral dysfunction in alcoholism. [source] Gamma band activity and its synchronization reflect the dysfunctional emotional processing in alexithymic personsPSYCHOPHYSIOLOGY, Issue 6 2006Atsushi Matsumoto Abstract In the present study, we investigated the gamma band response and its phase synchrony between electrodes in alexithymia, which is characterized by a disability in identifying and describing feelings. Individuals with high and low alexithymia scores were selected according to the scores on the 20-item Toronto Alexithymia Scale. EEG was recorded from alexithymic and nonalexithymic persons viewing emotionally negative or neutral stimuli. Nonalexithymic persons exhibited increased gamma band power and phase synchronization at the 400,450-ms time window when processing emotionally negative stimuli. Neither enhanced gamma band power nor phase synchronization was observed in alexithymic persons in the negative emotion condition. These results suggest that gamma band activity reflects emotional processing, and alexithymic persons may have a deficit in communication between brain regions or in the utilization of memory or emotional information during the processing of emotional stimuli. [source] Investigations of a simulated geomagnetic field experienced by the international space station on attentional performanceBIOELECTROMAGNETICS, Issue 1 2009Cristina Del Seppia Abstract We have previously reported that the exposure to an abnormal magnetic field simulating the one encountered by the International Space Station (ISS) orbiting around the Earth may enhance autonomic response to emotional stimuli. Here we report the results of the second part of that study which tested whether this field also affects cognitive functions. Twenty-four volunteers participated in the study, 12 exposed to the natural geomagnetic field and 12 to the magnetic field encountered by ISS. The test protocol consisted of a set of eight tests chosen from a computerized test battery for the assessment of attentional performance. The duration of exposure was 90 min. No effect of exposure to ISS magnetic field was observed on attentional performance. Bioelectromagnetics 30:45,51, 2009. © 2008 Wiley-Liss, Inc. [source] Memory with emotional content, brain amygdala and Alzheimer's diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 2 2009R. R. Schultz Objectives,,, A highly adaptive aspect of human memory is the enhancement of explicit, consciously accessible memory by emotional stimuli. We studied the performance of Alzheimer's disease (AD) patients and elderly controls using a memory battery with emotional content, and we correlated these results with the amygdala and hippocampus volume. Methods,,, Twenty controls and 20 early AD patients were subjected to the International Affective Picture System (IAPS) and to magnetic resonance imaging-based volumetric measurements of the medial temporal lobe structures. Results,,, The results show that excluding control group subjects with 5 or more years of schooling, both groups showed improvement with pleasant or unpleasant figures for the IAPS in an immediate free recall test. Likewise, in a delayed free recall test, both the controls and the AD group showed improvement for pleasant pictures, when education factor was not controlled. The AD group showed improvement in the immediate and delayed free recall test proportional to the medial temporal lobe structures, with no significant clinical correlation between affective valence and amygdala volume. Conclusion,,, AD patients can correctly identify emotions, at least at this early stage, but this does not improve their memory performance. [source] Influence of parental deprivation on the behavioral development in Octodon degus: Modulation by maternal vocalizationsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2003Katharina Braun Abstract Repeated separation from the family during very early stages of life is a stressful emotional experience which induces a variety of neuronal and synaptic changes in limbic cortical areas that may be related to behavioral alterations. First, we investigated whether repeated parental separation and handling, without separation from the family, leads to altered spontaneous exploratory behavior in a novel environment (open field test) in 8-day-old Octodon degus. Second, we tested whether the parentally deprived and handled animals display different stimulus-evoked exploratory behaviors in a modified open field version, in which a positive emotional stimulus, the maternal call, was presented. In the open field test a significant influence of previous emotional experience was found for the parameters of running, rearing, and vocalization. Parentally deprived degus displayed increased horizontal (running) and vertical (rearing) motoric activities, but decreased vocalization, compared to normal and handled controls. The presentation of maternal vocalizations significantly modified running, vocalization, and grooming activities, which in the case of running activity was dependent on previous emotional experience. Both deprivation-induced locomotor hyperactivity together with the reduced behavioral response towards a familiar acoustic emotional signal are similar to behavioral disturbances observed in human attachment disorders. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 237,245, 2003. [source] | ||||||||||||||||