Ethical and practical considerations in managing incidental findings in functional magnetic resonance imaging

Functional magnetic resonance imaging has emerged as a powerful tool for mapping the neurologic underpinnings of sensory, motor and cognitive function. Much of this evolution carries assumptions about the subject population under study and, in particular, the neurologic status of subjects entered into studies either as healthy controls or as belonging to a specific disease group. Recent reports of incidental MRI abnormalities in normal volunteers for fMRI studies have brought to attention a variety of practical challenges and ethical dilemmas for researchers, many of whom are not physicians and most of whom have no formal radiological training. We propose a minimum standard for consenting subjects in fMRI protocols, and consider strategies over the longer term that call for expert physician participation, archiving of incidental findings including false positives, and the adoption of guidelines for handling variation in neural activations or performance that appear outside expected norms.     

Encoding specificity manipulations do affect retrieval from memory

In a recent article, P.A. Higham (2002) [Strong cues are not necessarily weak: Thomson and Tulving (1970) and the encoding specificity principle revisited. Memory &Cognition, 30, 67-80] proposed a new way to analyze cued recall performance in terms of three separable aspects of memory (retrieval, monitoring, and report bias) by comparing performance under both free-report and forced-report instructions. He used this method to derive estimates of these aspects of memory in an encoding specificity experiment similar to that reported by D.M. Thomson and E. Tulving (1970) [Associative encoding and retrieval: weak and strong cues. Journal of Experimental Psychology, 86, 255-262]. Under forced-report instructions, the encoding specificity manipulation did not affect performance. Higham concluded that the manipulation affected monitoring and report bias, but not retrieval. I argue that this interpretation of the results is problematic because the Thomson and Tulving paradigm is confounded, and show in three experiments using a more appropriate design that encoding specificity manipulations do affect performance in forced-report cued recall. Because in Higham's framework forced-report performance provides a measure of retrieval that is uncontaminated by monitoring and report bias it is concluded that encoding specificity manipulations do affect retrieval from memory.     

An investigation of Taiwanese early adolescents' views about the nature of science

This study developed a Pupils' Nature of Science Scale, including the subscales of the invented and changing nature of science, the role of social negotiation on science, and cultural context on science, to assess early adolescents' views about the nature of science. More than 6,000 fifth and sixth graders in Taiwan responded to the Scale. The study revealed that the adolescents had quite different perspectives toward different subscales of the nature of science. Moreover, male adolescents tended to express more constructivist-oriented views toward the nature of science than did their female counterparts. The adolescents of different grades and races also displayed varying views toward the nature of science.     

Transforming mental health care for children and their families

In April 2002, the President's New Freedom Commission on Mental Health was created by executive order to study the mental health care delivery system in our nation and to make recommendations for improvements so that individuals with serious mental disorders can live, work, learn, and fully participate in their homes and communities. In its report, "Achieving the Promise: Transforming Mental Health Care in America," the commission provided strategies to address critical infrastructure, practice, and research issues. This article focuses on the work of the commission's Subcommittee on Children and Families, describing its vision for mental health service delivery for children and providing suggestions for strengthening community-based care for youths with or at risk of behavioral health disorders. Training, research, practice, and policy implications for psychologists are discussed.     

Attention capacity and task difficulty in visual search

When a visual search task is very difficult (as when a small feature difference defines the target), even detection of a unique element may be substantially slowed by increases in display set size. This has been attributed to the influence of attentional capacity limits. We examined the influence of attentional capacity limits on three kinds of search task: difficult feature search (with a subtle featural difference), difficult conjunction search, and spatial-configuration search. In all 3 tasks, each trial contained sixteen items, divided into two eight-item sets. The two sets were presented either successively or simultaneously. Comparison of accuracy in successive versus simultaneous presentations revealed that attentional capacity limitations are present only in the case of spatial-configuration search. While the other two types of task were inefficient (as reflected in steep search slopes), no capacity limitations were evident. We conclude that the difficulty of a visual search task affects search efficiency but does not necessarily introduce attentional capacity limits.     

Antecedents of Taiwanese adolescents' purchase intention toward the merchandise of a celebrity: the moderating effect of celebrity adoration

The purpose of the present study was to investigate the relative importance of adolescents' attitude toward an act (the degree to which the person had a favorable or unfavorable evaluation or appraisal of the act's behavior in question), perceived norm, and perceived behavioral control in predicting Taiwanese adolescents' intention to purchase the merchandise of a celebrity when they had different levels of celebrity adoration. The present results showed that the relative strengths of attitude toward the act and the perception of behavioral control in predicting purchase intention toward the merchandise of a celebrity were stronger for adolescents in the celebrity adoration group than for adolescents in the celebrity nonadoration group. On the other hand, the relative importance of the perceived norm in predicting the attitude toward the act and the purchase intention was stronger for adolescents in the celebrity nonadoration group than for adolescents in the celebrity adoration group.     

Expectation and repetition effects in searching for featural singletons in very brief displays

We studied the effects of expectation and repetition on searching for singletons in very brief displays. In Experiment 1, we found that when a given feature defined the singleton for a whole block--so that in every trial the subject could expect a particular target feature--search accuracy was significantly higher than when the feature setting was randomly redetermined from trial to trial. However, an unexpected repetition triggered almost no advantage. In Experiment 2, we found no advantage for expected alternation. Experiments 3 and 4 demonstrated that there is little or no advantage for perception in conditions allowing only for target-feature facilitation or distractor-feature inhibition. We propose that in singleton search a division of feature space facilitates detection, and that this division works best under conditions of expected repetition. Experiment 5 replicated Experiment 1, but in Experiment 5 we examined response times and long display exposures. Results suggested that previous findings of singleton priming reflect mainly postperceptual factors.     

Visual short-term memory load suppresses temporo-parietal junction activity and induces inattentional blindness

The right temporo-parietal junction (TPJ) is critical for stimulus-driven attention and visual awareness. Here we show that as the visual short-term memory (VSTM) load of a task increases, activity in this region is increasingly suppressed. Correspondingly, increasing VSTM load impairs the ability of subjects to consciously detect the presence of a novel, unexpected object in the visual field. These results not only demonstrate that VSTM load suppresses TPJ activity and induces inattentional blindness, but also offer a plausible neural mechanism for this perceptual deficit: suppression of the stimulus-driven attentional network.     

青少年性发展的差异及其对人格发展的影响

研究青少年性发育现状及其对性心理与人格发展的影响。方法：采用统一编制的《中学生性现状调查问卷》及16PF人格问卷,采用分层抽样方法,对江西4所中学的1000名学生进行问卷调查。结果：(1)青少年手淫行为发生率、与异性交往愿望及性冲动等方面均存在性别差异和年级差异;(2)性成熟的青少年的多种人格特征与未成熟的存在显著性差异。结论：青少年性生理发育正常,但在性心理方面很不成熟,对手淫、性冲动和异性交往等方面问题较多,性发展影响青少年人格发展。