Contextual cuing by global features

In visual search tasks, attention can be guided to a target item--appearing amidst distractors--on the basis of simple features (e.g., finding the red letter among green). Chun and Jiang's (1998) contextual cuing effect shows that reaction times (RTs) are also speeded if the spatial configuration of items in a scene is repeated over time. In the present studies, we ask whether global properties of the scene can speed search (e.g., if the display is mostly red, then the target is at location X). In Experiment 1A, the overall background color of the display predicted the target location, and the predictive color could appear 0, 400, or 800 msec in advance of the search array. Mean RTs were faster in predictive than in nonpredictive conditions. However, there was little improvement in search slopes. The global color cue did not improve search efficiency. Experiments 1B-1F replicated this effect using different predictive properties (e.g., background orientation-texture and stimulus color). The results showed a strong RT effect of predictive background, but (at best) only a weak improvement in search efficiency. A strong improvement in efficiency was found, however, when the informative background was presented 1,500 msec prior to the onset of the search stimuli and when observers were given explicit instructions to use the cue (Experiment 2).     

Change in perceptual form attenuates the use of the fluency heuristic in recognition

Four experiments (total N=295) were conducted to determine whether within-modality changes in perceptual form between the study and the test phases of an experiment would moderate the role of the fluency heuristic in recognition memory. Experiment 1 showed that a change from pictures to words reduced the role of fluency in recognition memory. In Experiment 2, the same result was found using counterfeit study lists that supposedly consisted of pictures or words. Experiments 3 and 4 showed that changes in the font used to present the study and test words also attenuated the contribution of fluency to the recognition decision when font change was manipulated between subjects, but not within subjects. Results suggest that the fluency heuristic is subject to metacognitive control, since participants' attributions of perceptual fluency depend on the perceived usefulness of fluency as a cue to recognition.     

Restraint stress and corticotropin releasing hormone modulation of murine cutaneous POMC mRNA

The skin is a unique immunological defense barrier that protects the organism from occupational and environmental exposures and provides a model system in which to evaluate the interaction of the central nervous system with the peripheral immune response. In the studies presented here, we tested mild, acute restraint stress activation of the cutaneous corticotropin releasing hormone-pro-opiomelanocortin (CRH-POMC) axis. We verified that 2 h restraint stress increased the serum concentration of corticosterone and alpha-melanocyte stimulating hormone. We report for the first time that CRH upregulates POMC mRNA expression in mouse skin in vitro. We also demonstrated, by RT-PCR, that 2,4 di-nitrofluorobenzene (DNFB) upregulates cutaneous POMC mRNA expression, the production of which is suppressed by restraint stress. These data confirm the presence and functionality of two hormones of the hypothalamo-pituitary axis in the skin and suggest that activation of the central hypothalamo-pituitary-adrenal axis may over ride activation of the cutaneous CRH-POMC mechanism in the development of DNFB-stimulated allergic contact dermatitis.     

Suspicious minds: The motive to acquire relationship‐threatening information

In four studies, we obtained evidence for the reliability and validity of a 21‐item scale designed to measure a new theoretical construct: individual differences in the motivation to acquire relationship‐threatening information (hereafter, MARTI). Study 1 provided evidence for the MARTI scale's reliability and discriminant validity, revealing that it was reliable and not significantly correlated with measures of the Big Five personality traits, adult attachment styles, or more general social orientations. Studies 2 and 3 provided evidence for the scale's convergent and discriminant validity, showing that dating partners with higher MARTI scores (i.e., those who were more motivated to acquire relationship‐threatening information) scored lower in relational trust and reported engaging in more “suspicion behaviors.” Study 4 provided behavioral evidence for the scale's predictive validity, revealing that (a) dating partners with higher MARTI scores were more likely to break up within 5 months, and (b) the breakup rate was most pronounced for dating partners who scored higher on the scale and who also reported being less close. We discuss how this new construct and measure can be used to study important relationship dynamics.

相似文献   

Visual word recognition without central attention: evidence for greater automaticity with advancing age

The present experiments examined the automaticity of word recognition. The authors examined whether people can recognize words while central attention is devoted to another task and how this ability changes across the life span. In Experiment 1, a lexical decision Task 2 was combined with either an auditory or a visual Task 1. Regardless of the Task 1 modality, Task 2 word recognition proceeded in parallel with Task 1 central operations for older adults but not for younger adults. This is a rare example of improved cognitive processing with advancing age. When Task 2 was nonlexical (Experiment 2), however, there was no evidence for greater parallel processing for older adults. Thus, the processing advantage appears to be restricted to lexical processes. The authors conclude that greater cumulative experience with lexical processing leads to greater automaticity, allowing older adults to more efficiently perform this stage in parallel with another task.     

Do multielement visual tracking and visual search draw continuously on the same visual attention resources?

Multielement visual tracking and visual search are 2 tasks that are held to require visual-spatial attention. The authors used the attentional operating characteristic (AOC) method to determine whether both tasks draw continuously on the same attentional resource (i.e., whether the 2 tasks are mutually exclusive). The authors found that observers can search and track within the same trial significantly better than would be predicted if the 2 tasks were mutually exclusive. In fact, the AOC for tracking and search is similar to that for tracking and auditory monitoring. The results of additional experiments support an attention-switching account for this high level of dual-task performance in which a single attentional resource is efficiently switched between the tracking and search. The results provide important constraints for architectures of visual selective attention and the mechanisms of multielement tracking.     

Evidence for an activation locus of the word-frequency effect in lexical decision

The authors report a lexical decision experiment designed to determine whether activation is the locus of the word-frequency effect. K. R. Paap and L. S. Johansen (1994) reported that word frequency did not affect lexical decisions when exposure durations were brief; they accounted for this by proposing that data-limited conditions prevented late-occurring verification processes. Subsequently, P. A. Allen, A. F. Smith, M. Lien, T. A. Weber, and D. J. Madden (1997) and K. R. Paap, L. S. Johansen, E. Chun, and P. Vonnahme (2000) reported additional evidence that word-frequency effects do and do not have an activation locus, respectively. The authors further tested this issue in a lexical decision experiment using data-limited procedures--predicted by verification models to eliminate word-frequency effects. The authors observed word-frequency effects using individually determined exposure durations that were only 1 screen cycle longer than the exposure duration that yielded chance performance. Word-frequency effects persisted even when an adjusted measure of performance was used.     

Understanding the social costs of narcissism: the case of the tragedy of the commons

Two studies examined narcissism and behavior in a commons dilemma. Study 1 used a four-person, laboratory-based task and Study 2 used a dyadic task. Participants were told that they represented one of four (Study 1) or two (Study 2) forestry companies and then were asked to harvest timber from a renewable forest. Narcissism was found to be positively related to acquisitive goals and harvesting more timber in the initial round. The more narcissists harvesting in the competitive group of four (Study 1) or dyad (Study 2), the less timber was harvested overall and the more rapidly the forest was depleted. Within competitive groups and dyads, however, narcissists harvested more than the nonnarcissists competing with them. In all, narcissism provided a benefit to the self, but at a long-term cost to other individuals and to the commons.     

The emerging fragile X premutation phenotype: evidence from the domain of social cognition

Fragile X syndrome is a neurodevelopmental disorder that is caused by large methylated expansions of a CGG repeat (>200) region upstream of the FMR1 gene that results in the lack of expression of the fragile X mental retardation protein (FMRP). Affected individuals display a neurobehavioral phenotype that includes a significant impairment in social cognition alongside deficits in attentional control, inhibition and working memory. In contrast, relatively little is known about the trajectory and specificity of any cognitive impairment associated with the fragile X premutation ("carrier-status") (approximately 55-200 repeats). Here, we focus on one aspect of cognition that has been well documented in the fragile X full mutation, namely social cognition. The results suggest that premutation males display a pattern of deficit similar in profile, albeit milder in presentation, to that of the full mutation. However, little evidence emerged for a correlation between CGG repeat length and severity of phenotypic outcomes. The findings are discussed in the context of functional neuroimaging and brain-behaviour-molecular correlates. We speculate that the deficiencies in social cognition are attributable to impairment of neural pathways modulated by the cerebellum.     

Recognition of conspecific odors by laboratory rats (Rattus norvegicus) does not show context specificity

This experiment investigated how contextual cues affect recognition of conspecific odors in laboratory rats (Rattus norvegicus). Rats received 5 encounters with the same odor in the same context. For the 6th test encounter, all rats received a simultaneous presentation of the original odor and a novel odor. The authors tested 1 group of rats (context same) in the same context as before. For the remaining 2 groups, the test encounter was in a different context that 1 group (context different) had experienced but that 1 group (context novel) had not. A significant preference to investigate the novel odor by context-same and context-different rats, but not by context-novel rats, suggests that odor recognition can occur following transfer to a different, but familiar, test context, indicating a lack of context specificity.