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991.
This study investigated stress symptoms before and after the September 11, 2001 terrorist attack on the World Trade Center. Responses to the Smith Stress Symptoms Inventory were compared for Chicago area college students assessed 1 to 5 weeks after 9/11 (n=149) and a comparable sample tested up to 5 months prior to 9/11 (n=320). Post-9/11 participants scored higher on Attention Deficit. Contrary to prior research, post-9/11 participants did not score higher on distress, including Worry, Autonomic Arousal/Anxiety, Striated Muscle Tension, Depression, and Anger. It is suggested that those indirectly exposed to a terrorist attack may display traditional symptoms of distress and arousal (as suggested by previous research). Later symptoms of attention deficit and distancing may emerge. This work was based on independent pre- and post-9/11 samples and must be replicated longitudinally as a test-retest to draw conclusions regarding change over time. 相似文献
992.
Richard Gray 《Philosophical Studies》2003,115(3):245-256
According to Tyes PANIC theory of consciousness, perceptualstates of creatures which are related to a disjunction ofexternal contents will fail to represent sensorily, andthereby fail to be conscious states. In this paper I arguethat heat perception, a form of perception neglected in therecent literature, serves as a counterexample to Tyesradical externalist claim. Having laid out Tyes `absentqualia scenario, the PANIC theory from which it derivesand the case of heat perception as a counterexample, Idefend the putative counterexample against three possibleresponses: (1) that heat perception represents general(i.e. non-disjunctive) intrinsic properties of objects,(2) that heat perception represents the non-specific heatenergy that is transferred between a subjects body andanother body and (3) that heat perception exclusivelyrepresents heat properties of the subjects own body. 相似文献
993.
Bohannon RW 《Perceptual and motor skills》2003,97(1):68-70
Inpatients with stroke spend the vast majority of their time in non-therapeutic activities. Their engagement in more therapeutic time seems warranted on the basis of research on skill development and intensity of rehabilitation. Means of providing such time, although challenging, should be pursued and their benefits investigated. 相似文献
994.
The cognitive and neural architecture of sequence representation 总被引:17,自引:0,他引:17
The authors theorize that 2 neurocognitive sequence-learning systems can be distinguished in serial reaction time experiments, one dorsal (parietal and supplementary motor cortex) and the other ventral (temporal and lateral prefrontal cortex). Dorsal system learning is implicit and associates noncategorized stimuli within dimensional modules. Ventral system learning can be implicit or explicit It also allows associating events across dimensions and therefore is the basis of cross-task integration or interference, depending on degree of cross-task correlation of signals. Accordingly, lack of correlation rather than limited capacity is responsible for dual-task effects on learning. The theory is relevant to issues of attentional effects on learning; the representational basis of complex, sequential skills; hippocampal-versus basal ganglia-based learning; procedural versus declarative memory; and implicit versus explicit memory. 相似文献
995.
Bernardi RA 《Psychological reports》2003,93(1):135-142
This study examined the differential moderating effects associated with field dependence-independence and perceptions of stress on students' performance after controlling for SAT Mathematics and Verbal scores as well as students' actual effort on homework. The average performance of 178 third-year accounting majors over three examinations was used to evaluate their understanding of financial accounting. The students also took the Group Embedded Figures Test. While the data indicate that the most significant variables were students' effort, SAT Verbal scores, and their perceptions of stress, these variables were differentially associated with students' performance depending upon whether the student was classified as a field-independent or field-dependent learner. 相似文献
996.
Interval timing in operant conditioning is the learned covariation of a temporal dependent measure such as wait time with a temporal independent variable such as fixed-interval duration. The dominant theories of interval timing all incorporate an explicit internal clock, or "pacemaker," despite its lack of independent evidence. The authors propose an alternative, pacemaker-free view that demonstrates that temporal discrimination can be explained by using only 2 assumptions: (a) variation and selection of responses through competition between reinforced behavior and all other, elicited, behaviors and (b) modulation of the strength of response competition by the memory for recent reinforcement. The model departs radically from existing timing models: It shows that temporal learning can emerge from a simple dynamic process that lacks a periodic time reference such as a pacemaker. 相似文献
997.
describe two aphasic patients, with impaired processing of vowels and consonants, respectively. The impairments could not be captured according to the sonority hierarchy or in terms of a feature level analysis. Caramazza et al. claim that this dissociation demonstrates separate representation of the categories of vowels and consonants in speech processing. We present two connectionist models of the management of phonological representations. The models spontaneously develop separable processing of vowels and consonants. The models have two hidden layers and are given as input vowels and consonants represented in terms of their phonological distinctive features. The first model is presented with feature bundles one at a time and the hidden layers have to combine their output to reproduce a unified copy of the feature bundle. In the second model a "fine-coded" layer receives information about feature bundles in isolation, and a "coarse-coded" layer receives information about each feature bundle in the context of the prior and subsequent feature bundle. Coarse-coding facilitated processing of vowels and fine-coding processing of consonants. These models show that separable processing of vowels and consonants is an emergent effect of modular processors operating on feature-based representations. We argue that it is not necessary to postulate an independent level of representation for the consonant/vowel distinction, separate from phonological distinctive features. 相似文献
998.
Davidson RJ 《Brain and cognition》2003,52(1):129-132
This brief commentary highlights seven sins in the study of emotion that are explicitly treated in contemporary affective neuroscience. These sins are (1) Affect and cognition are subserved by separate and independent neural circuits; (2) Affect is subcortical; (3) Emotions are in the head; (4) Emotions can be studied from a purely psychological perspective; (5) Emotions are similar in structure across age and species; (6) Specific emotions are instantiated in discrete locations in the brain; and (7) Emotions are conscious feeling states. Each of these is briefly discussed and evidence from affective neuroscience that bears on these sins is noted. The articles in this Special Issue underscore the vitality of research in affective neuroscience and illustrate how some of these sins can be addressed and rectified using concepts and methods from affective neuroscience. 相似文献
999.
1000.
It is well established that motion aftereffects (MAEs) can show interocular transfer (IOT); that is, motion adaptation in one eye can give a MAE in the other eye. Different quantification methods and different test stimuli have been shown to give different IOT magnitudes, varying from no to almost full IOT. In this study, we examine to what extent IOT of the dynamic MAE (dMAE), that is the MAE seen with a dynamic noise test pattern, varies with velocity of the adaptation stimulus. We measured strength of dMAE by a nulling method. The aftereffect induced by adaptation to a moving random-pixel array was compensated (nulled), during a brief dynamic test period, by the same kind of motion stimulus of variable luminance signal-to-noise ratio (LSNR). The LSNR nulling value was determined in a Quest-staircase procedure. We found that velocity has a strong effect on the magnitude of IOT for the dMAE. For increasing speeds from 1.5 deg s(-1) to 24 deg s(-1) average IOT values increased about linearly from 18% to 63% or from 32% to 83%, depending on IOT definition. The finding that dMAEs transfer to an increasing extent as speed increases, suggests that binocular cells play a more dominant role at higher speeds. 相似文献