Browsing by Subject "Arousal"
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Item Open Access Amygdala-prefrontal cortex functional connectivity during threat-induced anxiety and goal distraction.(Biol Psychiatry, 2015-02-15) Gold, Andrea L; Morey, Rajendra A; McCarthy, GregoryBACKGROUND: Anxiety produced by environmental threats can impair goal-directed processing and is associated with a range of psychiatric disorders, particularly when aversive events occur unpredictably. The prefrontal cortex (PFC) is thought to implement controls that minimize performance disruptions from threat-induced anxiety and goal distraction by modulating activity in regions involved in threat detection, such as the amygdala. The inferior frontal gyrus (IFG), orbitofrontal cortex (OFC), and ventromedial PFC (vmPFC) have been linked to the regulation of anxiety during threat exposure. We developed a paradigm to determine if threat-induced anxiety would enhance functional connectivity between the amygdala and IFG, OFC, and vmPFC. METHODS: Healthy adults performed a computer-gaming style task involving capturing prey and evading predators to optimize monetary rewards while exposed to the threat of unpredictable shock. Psychophysiological recording (n = 26) and functional magnetic resonance imaging scanning (n = 17) were collected during the task in separate cohorts. Task-specific changes in functional connectivity with the amygdala were examined using psychophysiological interaction analysis. RESULTS: Threat exposure resulted in greater arousal measured by increased skin conductance but did not influence performance (i.e., monetary losses or rewards). Greater functional connectivity between the right amygdala and bilateral IFG, OFC, vmPFC, anterior cingulate cortex, and frontopolar cortex was associated with threat exposure. CONCLUSIONS: Exposure to unpredictable threat modulates amygdala-PFC functional connectivity that may help maintain performance when experiencing anxiety induced by threat. Our paradigm is well-suited to explore the neural underpinnings of the anxiety response to unpredictable threat in patients with various anxiety disorders.Item Open Access Brain activity during episodic retrieval of autobiographical and laboratory events: an fMRI study using a novel photo paradigm.(J Cogn Neurosci, 2004-11) Cabeza, Roberto; Prince, Steve E; Daselaar, Sander M; Greenberg, Daniel L; Budde, Matthew; Dolcos, Florin; LaBar, Kevin S; Rubin, David CFunctional neuroimaging studies of episodic memory retrieval generally measure brain activity while participants remember items encountered in the laboratory ("controlled laboratory condition") or events from their own life ("open autobiographical condition"). Differences in activation between these conditions may reflect differences in retrieval processes, memory remoteness, emotional content, retrieval success, self-referential processing, visual/spatial memory, and recollection. To clarify the nature of these differences, a functional MRI study was conducted using a novel "photo paradigm," which allows greater control over the autobiographical condition, including a measure of retrieval accuracy. Undergraduate students took photos in specified campus locations ("controlled autobiographical condition"), viewed in the laboratory similar photos taken by other participants (controlled laboratory condition), and were then scanned while recognizing the two kinds of photos. Both conditions activated a common episodic memory network that included medial temporal and prefrontal regions. Compared with the controlled laboratory condition, the controlled autobiographical condition elicited greater activity in regions associated with self-referential processing (medial prefrontal cortex), visual/spatial memory (visual and parahippocampal regions), and recollection (hippocampus). The photo paradigm provides a way of investigating the functional neuroanatomy of real-life episodic memory under rigorous experimental control.Item Open Access Emotion and autobiographical memory: considerations from posttraumatic stress disorder.(Phys Life Rev, 2010-03) Rubin, David CItem Open Access Emotional Modulation of Time Perception(2014) Lake, JessicaOur perception of time is not veridical but rather is consistently modulating by changing dynamics in our environment. Anecdotal experiences suggest that emotions can be powerful modulators of time perception; nevertheless, the mechanisms underlying emotion-induced temporal distortions remain unclear. Widely accepted pacemaker-accumulator models of time perception suggest that changes in arousal and attention have unique influences on temporal judgments and contribute to emotional distortions of time perception. However, such models conflict with current views of arousal and attention and their interaction from the perspective of affective and cognitive science. The aim of this dissertation was to more clearly examine the role of arousal and attention in driving emotion-induced temporal distortions by explicitly manipulating and measuring these constructs using well-established timing procedures within the context of affective manipulations induced via classical conditioning and drug administration. Measures of physiological arousal and subjective measures of top-down attention to emotional stimuli were assessed both within and across subjects. The findings reported here suggest that current models of time perception do not adequately explain the variability in emotion-induced temporal distortions. Instead these findings provide support for a new theoretical model of emotion-induced temporal distortions proposed in the current manuscript that emphasizes both the unique and interactive influences of arousal and attention on time perception, dependent on temporal dynamics, event relationships, and individual differences. Collectively, these findings may point to plausible neurobiological mechanisms of emotion-induced temporal distortions and have important implications for our understanding of how emotions may modulate our perceptual experiences in service of adaptively responding to biologically relevant stimuli.
Item Open Access Perceived discrimination and health: a meta-analytic review.(Psychol Bull, 2009-07) Pascoe, Elizabeth A; Smart Richman, LauraPerceived discrimination has been studied with regard to its impact on several types of health effects. This meta-analysis provides a comprehensive account of the relationships between multiple forms of perceived discrimination and both mental and physical health outcomes. In addition, this meta-analysis examines potential mechanisms by which perceiving discrimination may affect health, including through psychological and physiological stress responses and health behaviors. Analysis of 134 samples suggests that when weighting each study's contribution by sample size, perceived discrimination has a significant negative effect on both mental and physical health. Perceived discrimination also produces significantly heightened stress responses and is related to participation in unhealthy and nonparticipation in healthy behaviors. These findings suggest potential pathways linking perceived discrimination to negative health outcomes.Item Open Access The temporal distribution of autobiographical memory: changes in reliving and vividness over the life span do not explain the reminiscence bump.(Mem Cognit, 2011-01) Janssen, Steve MJ; Rubin, David C; St Jacques, Peggy LWhen autobiographical memories are elicited with word cues, personal events from middle childhood to early adulthood are overrepresented compared to events from other periods. It is, however, unclear whether these memories are also associated with greater recollection. In this online study, we examined whether autobiographical memories from adolescence and early adulthood are recollected more than memories from other lifetime periods. Participants rated personal events that were elicited with cue words on reliving or vividness. Consistent with previous studies, most memories came from the period in which the participants were between 6 and 20 years old. The memories from this period were not relived more or recalled more vividly than memories from other lifetime periods, suggesting that they do not involve more recollection. Recent events had higher levels of reliving and vividness than remote events, and older adults reported a stronger recollective experience than younger adults.Item Open Access Vivid memories.(Cognition, 1984-02) Rubin, DC; Kozin, M