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901.
This research examined the effects of hands-free cell phone conversations on simulated driving. The authors found that these conversations impaired driver's reactions to vehicles braking in front of them. The authors assessed whether this impairment could be attributed to a withdrawal of attention from the visual scene, yielding a form of inattention blindness. Cell phone conversations impaired explicit recognition memory for roadside billboards. Eye-tracking data indicated that this was due to reduced attention to foveal information. This interpretation was bolstered by data showing that cell phone conversations impaired implicit perceptual memory for items presented at fixation. The data suggest that the impairment of driving performance produced by cell phone conversations is mediated, at least in part, by reduced attention to visual inputs. 相似文献
902.
Bipolar disorder is underdiagnosed and often mistaken for unipolar depression. Bipolar patients spend 33% of their time in a state of depression compared to 11% of time spent in a manic state. Duration of time depressed and severity of depression are associated with increased risk for suicide, which occurs in 10% to 20% of bipolar patients. Antidepressants are increasingly being used as adjuncts in the depressed phase of bipolar disorder, although they provide a moderate risk for switch into mania. Lithium and some antiepileptics and atypical antipsychotics have shown antidepressant effects in the treatment of bipolar disorder. Other adjuncts for treatment-refractory patients include monoamine oxidase inhibitors and electroconvulsive therapy. 相似文献
903.
Early emotional experiences affect developing brain systems that subsequently mediate adult learning and memory in rodents. Here we test for similar effects in squirrel monkeys (Saimiri sciureus) four years after disruptions in early maternal availability. These conditions were previously shown to generate differences in emotional behavior, hypothalamic-pituitary-adrenal stress physiology, and right ventral medial prefrontal volumes determined in adulthood by magnetic resonance imaging. This report identifies in the same monkeys variability in reward-related memory on tests with a spatial reversal. Adult monkeys that more often selected locations repeatedly rewarded before each reversal had larger right ventral medial prefrontal volumes, but not hippocampal nor dorsolateral prefrontal volumes on the left or right brain side. Differences in performance were also discerned after each spatial reversal. These findings indicate that maternal availability alters developing ventral medial prefrontal brain regions involved in reward-related memory. 相似文献
904.
Wilson DA 《History of psychology》2003,6(1):89-109
Why was there a preponderance of women engaged in laboratory-based studies of animal behavior in Britain in the early years of the 20th century? As a new experimental subject with recently neglected potential, animal psychology then represented an opportunity for women to make further inroads into academic science. Because the study of psychology before World War I offered negligible professional opportunities for the application of the subject, the intake of students was restricted. Perhaps this encouraged academic access to it by aspiring female scientists who felt that career prospects, uncertain and socially unexpected of them in any case, were worth chancing for greater long-term rewards. The academic circumstances and contributions of 3 British female pioneers in experimental comparative psychology are discussed. 相似文献
905.
906.
907.
The psychometric properties of several commonly used verbal working memory measures were assessed. One hundred thirty-nine
individuals in five age groups (18–30, 50–59, 60–69, 70–79, and 80+ years) were tested twice (Time I and Time II) on seven
working memory span measures (alphabet span, backward digit span, missing digit span, subtract 2 span, running item span,
and sentence span for syntactically simple and complex sentences), with an interval of approximately 6 weeks between testing.
There were significant effects of age on all but two of the tasks. All the measures had adequate internal consistency. Correlations
between performances at Time I and Time II were significant for all the tasks, other than the missing digit span task. The
magnitude of the correlations was similar across the age groups and ranged from .52 to .81. Classification of subjects into
discrete memory span groups on the basis of a single measure was highly inconsistent across testing sessions and tasks. Classification
into upper and lower quartiles was more stable than using a cutoff score for group membership or than classification into
high-, medium-, and low-span groups. Correlational analyses showed that there was a moderate relationship between performances
on many of the span tasks. Confirmatory factor analysis suggested that six of the seven tasks reflected a common factor. Both
test—retest reliability and stability of classification improved when a composite measure reflecting performance on several
tasks was used. 相似文献
908.
Scaling techniques for modeling directional knowledge 总被引:1,自引:0,他引:1
A common way for researchers to model or graphically portray spatial knowledge of a large environment is by applying multidimensional
scaling (MDS) to a set of pairwise distance estimations. We introduce two MDS-like techniques that incorporate people’s knowledge
of directions instead of (or in addition to) their knowledge of distances. Maps of a familiar environment derived from these
procedures were more accurate and were rated by participants as being more accurate than those derived from nonmetric MDS.
By incorporating people’s relatively accurate knowledge of directions, these methods offer spatial cognition researchers and
behavioral geographers a sharper analytical tool than MDS for studying cognitive maps. 相似文献
909.
In this study, we describe and analyze the ways in which high school students explored a virtual solar system (VSS). VSS is
a nonimmersive virtual environment that affords visual manipulations of space by altering its frame of reference. The Observer
software was used to code and analyze the participants’ real-time free-exploration task. Two basic behaviors were identified
across participants: establishing several home bases, and shifting between a still mode and a dynamic mode. Moreover, three
overall exploration patterns emerged: thebutterfly pattern represents a superficial mode of learning; thebee pattern represents an in-depth mode of studying the various celestial objects; and theeagle pattern represents a global approach of studying the complex system. This virtual reality environment promises to provide
a setting in which to further study consistent patterns and individual differences in exploration strategies. 相似文献
910.
Belgum D 《The journal of pastoral care & counseling : JPCC》2003,57(1):39-44
The author, acknowledging the reality of homeless persons in most communities, explores the meanings and dynamics of homelessness, and the need to recognize the variety of participants needing to be recognized in appreciating the complexity of this segment of society. He raises the issue of how pastoral caregivers become involved in providing authentic care to this sub-culture and offers examples from his own experiences as a volunteer chaplain in the Salvation Army Corps. 相似文献