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891.
There is a common assumption about pictures, that seeing them produces in us something like the same effects as seeing the things they depict. This assumption lies behind much empirical research into vision, where experiments often expose subjects to pictures of things in order to investigate the processes involved in cognizing those things themselves. Can philosophy provide any justification for this assumption? I examine this issue in the context of Flint Schier's account of pictorial representation. Schier attempts to infer the assumption from what he takes to be the fundamental facts about picturing. I argue that there is no plausible form of Schier's basic claims from which the assumption can be inferred. I then reject a second argument, that by appealing to the assumption Schier could explain why it is impossible to depict a particular without depicting it as having certain properties. I conclude that those sympathetic to the assumption need to articulate and defend some version of it suited to their needs.  相似文献   
892.
Previous fMRI studies have reported mixed evidence for the influence of selective attention on amygdala responses to emotional stimuli, with some studies showing “automatic” emotional effects to threat-related stimuli without attention (or even without awareness), but other studies showing a gating of amygdala activity by selective attention with no response to unattended stimuli. We recorded intracranial local field potentials from the intact left lateral amygdala in a human patient prior to surgery for epilepsy and tested, with a millisecond time resolution, for neural responses to fearful faces appearing at either task-relevant or task-irrelevant locations. Our results revealed an early emotional effect in the amygdala arising prior to, and independently of, attentional modulation. However, at a later latency, we found a significant modulation of the differential emotional response when attention was directed toward or away from fearful faces. These results suggest separate influences of emotion and attention on amygdala activation and may help reconcile previous discrepancies concerning the relative responsiveness of the human amygdala to emotional and attentional factors.  相似文献   
893.
Individuals with psychopathy are often characterized by emotional processing deficits, and recent research has examined the specific contexts and cognitive mechanisms that underlie these abnormalities. Some evidence suggests that abnormal features of attention are fundamental to emotional deficits in persons with psychopathy, but few studies have demonstrated the neural underpinnings responsible for such effects. Here, we use functional neuroimaging to examine attention–emotion interactions among incarcerated individuals (n = 120) evaluated for psychopathic traits using the Hare Psychopathy Checklist–Revised (PCL-R). Using a task designed to manipulate attention to emotional features of visual stimuli, we demonstrate effects representing implicit emotional processing, explicit emotional processing, attention-facilitated emotional processing, and vigilance for emotional content. Results confirm the importance of considering mechanisms of attention when evaluating emotional processing differences related to psychopathic traits. The affective-interpersonal features of psychopathy (PCL-R Factor 1) were associated with relatively lower emotion-dependent augmentation of activity in visual processing areas during implicit emotional processing, while antisocial-lifestyle features (PCL-R Factor 2) were associated with elevated activity in the amygdala and related salience network regions. During explicit emotional processing, psychopathic traits were associated with upregulation in the medial prefrontal cortex, insula, and superior frontal regions. Isolating the impact of explicit attention to emotional content, only Factor 1 was related to upregulation of activity in the visual processing stream, which was accompanied by increased activity in the angular gyrus. These effects highlight some important mechanisms underlying abnormal features of attention and emotional processing that accompany psychopathic traits.  相似文献   
894.
Before alcohol was generally known to cause birth defects, NIAAA in 1974 began funding a population-based Seattle study on alcohol use and pregnancy outcome. Women receiving prenatal care by mid-pregnancy were recruited (N = 1,529) and interviewed at home. Approximately 500 offspring exposed to a range of alcohol levels were examined on 11 occasions between day 1 and 25 years. Neuropsychological and neurobehavioral performance measures are correlated with prenatal alcohol dose, without substantial confounding by socio-demographic or rearing conditions, smoking, nutrition, or other drugs. Deficits in attention, arithmetic skill, spatial-visual memory, and IQ, as well as increased alcohol problems and psychiatric disorders are among offspring outcomes correlated at several ages with maternal drinking during and before pregnancy recognition. Findings are not confined to women who believed they had alcohol problems. Not all exposed offspring appear affected.  相似文献   
895.
This study investigated factors associated with social anxiety during early adolescence using multiple informants, including self and peer perspectives, teacher ratings, and direct observations. Negative social performance expectations, maladaptive coping strategies, and social skill deficits were examined as correlates of social anxiety and mediators linking social anxiety with poor peer relations. Participants were 84 middle school students (47 girls, 37 boys) over-sampled for elevated social anxiety. Analyses revealed correlations linking social anxiety with decreased peer acceptance and increased peer victimization. Path analysis indicated that negative social performance expectations and social withdrawal-disengagement accounted for the association between social anxiety and decreased peer acceptance. Social anxiety, self-directed coping strategies, and social withdrawal-disengagement were each directly linked with increased peer victimization for boys. The results replicate findings based on clinical samples, extend understanding of cognitive, social, and behavioral factors associated with social anxiety in middle school, and provide new information regarding gender differences in the correlates of social anxiety.  相似文献   
896.
897.
Two experiments examined sequential and simultaneous conditioned inhibition in an autoshaping preparation. In Experiment 1, a 5-sec coloured keylight (A) was reinforced when presented alone. However, reinforcement was withheld from trials on which A was preceded by one grid pattern or presented simultaneously with another pattern. A third (control) pattern was presented separately without reinforcement. Inhibition developed most strongly to the grid pattern presented simultaneously with A. However, a transfer test with another excitatory coloured keylight found both inhibitors to be equally strong whether they were tested in simultaneous or in sequential compound. Experiment 2 compared grid patterns that consistently had sequential or simultaneous relations to the excitor with one that was sometimes presented in sequential and sometimes in simultaneous compound. The mixed treatment pattern showed levels of inhibition like the simultaneous or sequential pattern, depending on the temporal relation it bore to A on a particular trial. These results suggest that sequential and simultaneous relations between inhibitors and excitors yield similar amounts of inhibition. However, that inhibition is better exhibited when tested in simultaneous compound with the excitor.  相似文献   
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