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Activity within the visual cortex can be influenced by the emotional salience of a stimulus, but it is not clear whether such cortical activity is modulated by the affective status of the individual. This study used functional magnetic resonance imaging (fMRI) to examine the relationship between affect ratings on the Positive and Negative Affect Schedule and activity within the occipital cortex of 13 normal-weight women while viewing images of high calorie and low calorie foods. Regression analyses revealed that when participants viewed high calorie foods, Positive Affect correlated significantly with activity within the lingual gyrus and calcarine cortex, whereas Negative Affect was unrelated to visual cortex activity. In contrast, during presentations of low calorie foods, affect ratings, regardless of valence, were unrelated to occipital cortex activity. These findings suggest a mechanism whereby positive affective state may affect the early stages of sensory processing, possibly influencing subsequent perceptual experience of a stimulus.  相似文献   
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Positive mood contributes to mental and physical wellbeing. The broaden-and-build theory (Fredrickson, 2001) proposed that the beneficial effects of positive mood on life quality result from attentional broadening. In this article, we systematically review (following PRISMA guidelines; Moher et al., 2009), a host of studies investigating the nature and extent of attentional changes triggered by the experience of positive mood, with a focus on vision. While several studies reported a broadening of attention, others found that positive mood led to a more diffuse information processing style. Positive mood appears to lessen attention selectivity in a way that is context-specific and bound to limitations. We propose a new framework in which we postulate that positive mood impacts the balance between internally and externally directed attention, through modulations of cognitive control processes, instead of broadening attention per se. This novel model is able to accommodate discrepant findings, seeks to translate the phenomenon of the so-called broadening of attention with positive mood into functional terms, and provides plausible neurobiological mechanisms underlying this effect, suggesting a crucial role of the anterior and posterior cingulate cortex in this interaction.  相似文献   
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We examined the cyclicity of negative mood relative to ovulation and ovulation disturbances in Menstrual Cycle Diary© data collected daily during a 1-year study of ovulation, exercise, and bone change. A validated quantitative basal temperature-based methodology was used to determine the onset of the luteal phase. ‘Feeling depressed’, ‘feeling anxious’, and ‘feeling angry/frustrated’ were scored on a scale of 0 (absent) to 4 (very intense). Mood scores were examined over two 15-day intervals centered on either ovulation/midpoint, or on the onset of flow. Data were available from 765 cycles of 62 healthy and initially ovulatory women with a mean age of 33.9?±?5.4 years. Of 739 cycles that could be classified, 532 (72%) were normally ovulatory, 185 (25%) were ovulatory with a short (<10 day) luteal phase, and 22 (3%) were anovulatory. Minor cyclic mood changes were present in both ovulatory and anovulatory menstrual cycles. In anovulatory cycles, mood tended to be more variable but less negative, with a time course that differed from that in ovulatory cycles. Mood scores did not differ based on luteal phase length or with hormone levels. Patterns and mechanisms of mood change in very symptomatic women appear to be essentially amplifications of normal experiences.  相似文献   
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This study assessed whether exercising whilst viewing natural or built scenes affected self-esteem (SE) and mood in adolescents. Twenty-five adolescents participated in three exercise tests on consecutive days. A graded exercise test established the work rate equivalent to 50% heart rate reserve for use in subsequent constant load tests (CLTs). Participants undertook two 15-min CLTs in random order viewing scenes of either natural or built environments. Participants completed Rosenberg’s SE scale and the adolescent profile of mood states questionnaire pre- and post-exercise. There was a significant main effect for SE (F(1) = 6.10; P < 0.05) and mood (F(6) = 5.29; P < 0.001) due to exercise, but no effect of viewing different environmental scenes (P > 0.05). Short bouts of moderate physical activity can have a positive impact on SE and mood in adolescents. Future research should incorporate field studies to examine the psychological effects of contact with real environments.  相似文献   
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The present study examined effects of simulated air travel on physical performance. In a randomized crossover design, 10 physically active males completed a simulated 5‐h domestic flight (DOM), 24‐h simulated international travel (INT), and a control trial (CON). The mild hypoxia, seating arrangements, and activity levels typically encountered during air travel were simulated in a normobaric, hypoxic altitude room. Physical performance was assessed in the afternoon of the day before (D ? 1 PM) and in the morning (D + 1 AM) and afternoon (D + 1 PM) of the day following each trial. Mood states and physiological and perceptual responses to exercise were also examined at these time points, while sleep quantity and quality were monitored throughout each condition. Sleep quantity and quality were significantly reduced during INT compared with CON and DOM (P < 0.01). Yo‐Yo Intermittent Recovery level 1 test performance was significantly reduced at D + 1 PM following INT compared with CON and DOM (P < 0.01), where performance remained unchanged (P > 0.05). Compared with baseline, physiological and perceptual responses to exercise, and mood states were exacerbated following the INT trial (P < 0.05). Attenuated intermittent‐sprint performance following simulated international air travel may be due to sleep disruption during travel and the subsequent exacerbated physiological and perceptual markers of fatigue.  相似文献   
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