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221.
How rapidly can attention move from one object to the next? Previous studies in which the dwell time paradigm was used have estimated attentional switch times of 200–500 msec, results incompatible with the search rate estimates of 25–50 msec shown in numerous visual search studies. It has been argued that dwell times are so long in the dwell time paradigm because the attentional shifts measured are unlike those used in visual search. In the present experiment, a variation of a visual search task was used, in which serial endogenous (volitional) deployments of attention were measured directly by means of a probe reaction time task. The experiment revealed a dwell time of about 250 msec, consistent with the faster estimates from other dwell time studies. This result suggests that endogenous shifts of attention may be relatively slow and that the faster attentional shifts estimated from visual search tasks may be due to the involvement of bottom-up processes. 相似文献
222.
Joerden JC 《Science and engineering ethics》2004,10(1):65-72
This article considers issues concerning cases where the use of placebo is lawful or is not lawful under aspects of German
criminal law. It will differentiate between cases of individual therapy and cases of supervised experiments within the scope
of medical tests. Thereby, it reveals that a medication of placebo with regard to an individual patient seems to be lawful
if there is no alternative possibility of a better treatment using a chemically effective medicine and if the limits of presumed
consent are complied with. On the other hand, in the context of the supervised experiment, the assignment of a patient to
a group treated with placebo is only lawful if the patient has been fully informed about the possibilities of a treatment
and if the patient has given consent to it.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003.
The author’s interests include International Criminal Law, Comparative Criminal Law and Philosophy of Law. 相似文献
223.
Darlene L. Witte‐Townsend Emily DiGiulio 《International Journal of Children's Spirituality》2004,9(2):127-142
Witte‐Townsend and DiGiulio explore some of the dimensions of knowing that children, teachers and parents may engage together during story‐time. They reflect on some of their own long‐term relationships with children and children's books, especially Phoebe Gilman's Something from nothing (published in 1992) and Simms Taback's Joseph had a little overcoat, published in 1999. The authors probe issues such as why children ask to hear a favourite story over and over and why they suddenly abandon all interest and move on to a new book. They explore the meaning of the silences that sometimes arise during story‐time, pooling around the young listeners as the last words of the book are read. Witte‐Townsend and DiGiulio remind us of the value of literature in the lives of children and they affirm that the reading and re‐reading of favourite stories enables the understanding of complex human issues and contributes significantly to social, emotional and spiritual growth. 相似文献
224.
Sleep is crucial to the 'off-line' consolidation of procedural memory. A recent study by Robertson et al. shows that this might hold true only if the task is trained explicitly, that is, with the subject being aware of the task structure. These new data add to emerging evidence that sleep-related memory consolidation involves an interaction between different memory systems. 相似文献
225.
Koster EH Crombez G Van Damme S Verschuere B De Houwer J 《Emotion (Washington, D.C.)》2004,4(3):312-317
According to models of attention and emotion, threat captures and holds attention. In behavioral tasks, robust evidence has been found for attentional holding but not for attentional capture by threat. An important explanation for the absence of attentional capture effects is that the visual stimuli used posed no genuine threat. The present study investigated whether visual cues that signal an aversive white noise can elicit attentional capture and holding effects. Cues presented in an attentional task were simultaneously provided with a threat value through an aversive conditioning procedure. Response latencies showed that threatening cues captured and held attention. These results support recent views on attention to threat, proposing that imminent threat captures attention in everyone. 相似文献
226.
Suicide rates may be affected by world news. Our objective was to investigate the possible impact of the terrorist attacks of September 11, 2001, on suicidal behavior in the Netherlands. There was evidence of an increase in rates of suicide and deliberate self-harm in the weeks immediately following the attacks. These findings contrast with Durkheim's (1897) original suggestion that suicide rates decline in times of war and outside threat but are in line with findings of increases in suicidal behavior after media coverage of lethal violence. 相似文献
227.
Much of cognitive aging research concerns whether age-associated differences in various cognitive performances can be accounted for by general explanatory constructs or whether several specific processes are involved. Structural equation models have been proposed to disentangle general and specific age-associated differences in cognitive performance. This article demonstrates that existing methods that employ stepwise procedures run the risk of biasing results toward general resource accounts. An alternative model representation (i.e., the nested factor model) is proposed that affords simultaneous estimation of general and specific effects and is applied to data from the Berlin Aging Study. Using the nested factor model allowed the authors to detect that specific group factors explained 25% of the age-associated variance in addition to the general factor. 相似文献
228.
The authors explored the temporal mechanism of attention deficit in children with attention-deficit/hyperactivity disorder (ADHD). In rapid serial visual presentation tasks in which two targets (T-sub-1 and T-sub-2) were presented in close temporal proximity among distractors, participants tried to identify T-sub-1 and detect T-sub-2 in one (dual-task) experiment and only to detect T-sub-2 in a second control (single-task) experiment. The sensitivity of T-sub-2 detection was analyzed using signal detection theory. The attentional blink--the impairment in T-sub-2 detection following the identification of T-sub-1--was increased in magnitude and protracted in the patients. Moreover, some ADHD children appeared to have a blink largely normal in magnitude but temporally displaced toward a later time. The authors hypothesize that a slower closing of the attention gate may mediate this specific attention impairment in ADHD children. 相似文献
229.
This study investigated whether parent-adolescent disagreement regarding adolescents' behavioral and emotional problems predicted adverse outcome. A Dutch sample of 15- to 18-year-olds was prospectively followed across a 4-year interval. The Child Behavior Checklist (CBCL: T. M. Achenbach, 1997) and Youth Self-Report (YSR; T. M. Achenbach, 1991b) were administered at initial assessment, and the following signs of poor outcome were assessed 4 years later: police/judicial contacts, expulsion from school/job, suicidal ideation, unwanted pregnancy, suicide attempts, deliberate self-harm, referral to mental health services, report of having a behavioral or emotional problem, and feeling the need for professional help without actually receiving help. Twenty CBCL syndrome scores, 23 YSR syndrome scores, and 16 discrepancy scores were significant predictors of poor outcome. It was concluded that to determine the prognosis of psychopathology in adolescents, discrepancies between informants may be important. 相似文献
230.
On the selective relation of frontal cortical asymmetry and anger-out versus anger-control 总被引:1,自引:0,他引:1
Hewig J Hagemann D Seifert J Naumann E Bartussek D 《Journal of personality and social psychology》2004,87(6):926-939
The model of anterior asymmetry and emotion proposes an asymmetric representation of approach and withdrawal systems in the left and right anterior brain regions. Within this framework, 3 different concepts have been related to anterior asymmetry: affective valence, motivational direction, and behavioral activation. The aim of the present study was an empirical investigation into the relation between anterior cortical activity and questionnaire measures related to the 3 dimensions positive versus negative affect, approach versus withdrawal motivation, and behavioral activation versus inhibition. Subjects with relative greater left than right frontal cortical activity showed higher anger-out scores and lower anger-control scores. These results support the hypothesis that motivational direction is related to frontal asymmetry (approach-left and withdrawal-right). Furthermore, subjects with greater bilateral (left and right) frontal cortical activity showed higher behavioral activation scores. This finding might suggest that behavioral activation is related to approach and withdrawal motivation. 相似文献