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Control Stimuli (control + stimulus)
Selected AbstractsInitial, habitual and compulsive alcohol use is characterized by a shift of cue processing from ventral to dorsal striatumADDICTION, Issue 10 2010Sabine Vollstädt-Klein ABSTRACT Aims During the development of drug addiction, initial hedonic effects decrease when substance use becomes habitual and ultimately compulsive. Animal research suggests that these changes are represented by a transition from prefrontal cortical control to subcortical striatal control and within the striatum from ventral to dorsal domains of the striatum, but only limited evidence exists in humans. In this study we address this hypothesis in the context of alcohol dependence. Design, setting and participants Non-abstinent heavy social drinkers (n = 21, 5.0 ± 1.5 drinks/day, 13 of them were alcohol-dependent according to DSM-IV) and light social drinkers (n = 10, 0.4 ± 0.4 drinks/day) were examined. Measurements We used a cue-reactivity functional magnetic resonance imaging (fMRI) design during which pictures of alcoholic beverages and neutral control stimuli were presented. Findings In the dorsal striatum heavy drinkers showed significant higher activations compared to light drinkers, whereas light social drinkers showed higher cue-induced fMRI activations in the ventral striatum and in prefrontal areas compared to heavy social drinkers [region of interest analyses, P < 0.05 false discovery rate (FDR)-corrected]. Correspondingly, ventral striatal activation in heavy drinkers correlated negatively with obsessive-compulsive craving, and furthermore we found a positive association between cue-induced activation in the dorsal striatum and obsessive-compulsive craving in all participants. Conclusions In line with our hypothesis we found higher cue-induced activation of the ventral striatum in social compared to heavy drinkers, and higher dorsal striatal activation in heavy drinkers. Increased prefrontal activation may indicate that social drinkers activate cortical control when viewing alcohol cues, which may prevent the development of heavy drinking or alcohol dependence. Our results suggest differentiating treatment research depending on whether alcohol use is hedonic or compulsive. [source] Distributed source modeling of language with magnetoencephalography: Application to patients with intractable epilepsyEPILEPSIA, Issue 10 2009Carrie R. McDonald Summary Purpose:, To examine distributed patterns of language processing in healthy controls and patients with epilepsy using magnetoencephalography (MEG), and to evaluate the concordance between laterality of distributed MEG sources and language laterality as determined by the intracarotid amobarbital procedure (IAP). Methods:, MEG was performed in 10 healthy controls using an anatomically constrained, noise-normalized distributed source solution (dynamic statistical parametric map, dSPM). Distributed source modeling of language was then applied to eight patients with intractable epilepsy. Average source strengths within temporoparietal and frontal lobe regions of interest (ROIs) were calculated, and the laterality of activity within ROIs during discrete time windows was compared to results from the IAP. Results:, In healthy controls, dSPM revealed activity in visual cortex bilaterally from ,80 to 120 ms in response to novel words and sensory control stimuli (i.e., false fonts). Activity then spread to fusiform cortex ,160,200 ms, and was dominated by left hemisphere activity in response to novel words. From ,240 to 450 ms, novel words produced activity that was left-lateralized in frontal and temporal lobe regions, including anterior and inferior temporal, temporal pole, and pars opercularis, as well as bilaterally in posterior superior temporal cortex. Analysis of patient data with dSPM demonstrated that from 350 to 450 ms, laterality of temporoparietal sources agreed with the IAP 75% of the time, whereas laterality of frontal MEG sources agreed with the IAP in all eight patients. Discussion:, Our results reveal that dSPM can unveil the timing and spatial extent of language processes in patients with epilepsy and may enhance knowledge of language lateralization and localization for use in preoperative planning. [source] ORIGINAL RESEARCH,PAIN: Misremembering Pain: Memory Bias for Pain Words in Women Reporting Sexual PainTHE JOURNAL OF SEXUAL MEDICINE, Issue 5 2009Lea Thaler MA ABSTRACT Introduction., The debate over the classification of dyspareunia as a sexual dysfunction or as a pain disorder raises the question of the comparative cognitive salience of sex and/or pain in the experience of women who report pain with intercourse. Refinements in our understanding of cognitive factors in the experience of pain with intercourse may be important in the development of effective treatments. Aim., This study aimed to compare the cognitive salience of sex and pain word stimuli in women reporting pain with intercourse and in a control group of women without sexual dysfunction. Methods., Twenty women reporting pain during sexual intercourse and 20 women reporting no sexual dysfunction (controls) participated in a memory protocol designed to detect differences as a function of group membership and type of stimulus (sex, pain, and two other control stimuli). Main Outcome Measures., Dependent measures were recall, recognition, intrusions, and false positives for sex words, pain words, and two other control word types. Results., Regardless of group membership, women had best recall for sex-related words; however, women reporting sexual pain evidenced more false memories for pain words than did control women, and pain words elicited more false memories than any other type of word for women with sexual pain. Conclusion., Results are interpreted to suggest that repeated activation through experience with persistent sexual pain may have contributed to the: (i) development of stronger semantic networks related to pain in comparison to no sexual dysfunction controls and; (ii) activation of pain networks more easily triggered by pain-related stimuli in women with sexual pain than in no sexual dysfunction controls. Sex, however, had not attained the cognitive salience of pain. Thaler L, Meana M, and Lanti A. Misremembering pain: Memory bias for pain words in women reporting sexual pain. J Sex Med 2009;6:1369,1377. [source] Stroop performance in bipolar disorder: further evidence for abnormalities in the ventral prefrontal cortexBIPOLAR DISORDERS, Issue 1 2006Dina M Kronhaus Objectives:, Bipolar patients are impaired in Stroop task performance, a measure of selective attention. Structural and functional abnormalities in task-associated regions, in particular the prefrontal cortex (PFC), have been reported in this population. We aimed to examine the relationship between functional abnormalities, impaired task performance and the severity of depressive symptoms in bipolar patients. Methods:, Remitted bipolar patients (n = 10; all medicated), either euthymic or with subsyndromal depression, and age-matched control subjects (n = 11) viewed 10 alternating blocks of incongruent Stroop and control stimuli, naming the colour of the ink. Neural response was measured using functional magnetic resonance imaging. We computed between-group differences in neural response and within-group correlations with mood and anxiety. Results:, There were no significant between-group differences in task performance. During the Stroop condition, controls demonstrated greater activation of visual and dorsolateral and ventrolateral prefrontal cortical areas; bipolar patients demonstrated relative deactivation within orbital and medial prefrontal cortices. Depression scores showed a trend towards a negative correlation with the magnitude of orbitofrontal cortex deactivation in bipolar patients, whereas state anxiety correlated positively with activation of dorsolateral PFC and precuneus in controls. Conclusions:, Our findings confirm previous reports of decreased ventral prefrontal activity during Stroop task performance in bipolar patients, and suggest a possible negative correlation between this and depression severity in bipolar patients. These findings further highlight the ventromedial PFC as a potential candidate for illness related dysfunction in bipolar disorder. [source] | ||||||||||