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141.
Twenty-four detoxified opiate addicts were randomized to an experimental group and a control group to evaluate efficacy of a group cue-exposure treatment to reduce or extinguish classically conditioned responses to drug-related stimuli. Assessment included psychophysiological responses (skin temperature, skin conductance level--SCL--, and heart rate) to a videotape and subjective measures (subjective craving, positive and negative affect) before and after the videotape. The experimental group received a group cue-exposure program to drug-related stimuli that comprised twelve treatment sessions administered three times weekly. The treatment program significantly reduced conditioned responses to drug-related stimuli, as measured by SCL and positive affect. 相似文献
142.
Structure and stimulus familiarity: a study of memory in chess-players with functional magnetic resonance imaging 总被引:1,自引:0,他引:1
A grandmaster and an international chess master were compared with a group of novices in a memory task with chess and non-chess stimuli, varying the structure and familiarity of the stimuli, while functional magnetic resonance images were acquired. The pattern of brain activity in the masters was different from that of the novices. Masters showed no differences in brain activity when different degrees of structure and familiarity where compared; however, novices did show differences in brain activity in such contrasts. The most important differences were found in the contrast of stimulus familiarity with chess positions. In this contrast, there was an extended brain activity in bilateral frontal areas such as the anterior cingulate and the superior, middle, and inferior frontal gyri; furthermore, posterior areas, such as posterior cingulate and cerebellum, showed great bilateral activation. These results strengthen the hypothesis that when performing a domain-specific task, experts activate different brain systems from that of novices. The use of the experts-versus-novices paradigm in brain imaging contributes towards the search for brain systems involved in cognitive processes. 相似文献
143.
Gurry F 《Science and engineering ethics》2005,11(1):13-20
Intellectual property has historically been a self-contained policy at the international level. With the introduction of the
TRIPs Agreement in 1994 and developments since the conclusion of the TRIPs Agreement, the relationship between intellectual
property policy and other areas of public policy has become much more complex and interactive. This shift reflects the centrality
of intellectual property in the knowledge economy, the rapid development of enabling technologies, notably the Internet and
biotechnology, and the advent of the networked society. The consequences of this shift are manifold and herald the increased
sophistication and complexity that may be expected of intellectual property regimes in the knowledge economy.
An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights
and Patents,” held in Warsaw, Poland on 23–24 April, 2004. 相似文献
144.
This study investigated the development of the frontal lobe action-monitoring system from late childhood and adolescence to early adulthood using ERP markers of error processing. Error negativity (ERN) and correct response negativity (CRN) potentials were recorded while adolescents and adults (aged 12-22 years, n = 23) performed two forced-choice visual reaction time tasks of differing complexity. Significant age differences were seen for behavioural and ERP responses to complex (infrequent, incompatible) trials: adolescents elicited an error negativity of reduced magnitude compared with adults. Furthermore, in contrast to adults, adolescents showed a non-significant differentiation between response-locked ERP components elicited by correct (CRN) and error responses (ERN). Behaviourally, adolescents corrected fewer errors in incompatible trials, and with increasing age there was greater post-error slowing. In conclusion, the neural systems underlying action-monitoring continue to mature throughout the second decade of life, and are associated with increased efficiency for fast error detection and correction during complex tasks. 相似文献
145.
When cued with generic happy and sad words, depressed individuals have been found to articulate contextually impoverished memories of autobiographical events. Although this pattern predicts a worse symptomatic course of disorder in some depressed samples, longitudinal findings with the cue-word paradigm are inconsistent. To address the etiological significance of autobiographical memories outside the cue-word paradigm, the authors used an idiographic interview in which depressed participants generated memories of their happiest and saddest lifetime events. Each memory was coded for detail and emotional intensity. At a 1-year follow-up, participants' levels of depressive symptoms were reassessed. Lower emotional intensity of saddest memories predicted higher levels of depressive symptoms at follow-up. Several implications for understanding sadness and emotional disclosure in depression are discussed. 相似文献
146.
Allhoff F 《The American journal of bioethics : AJOB》2005,5(1):50-1; author reply W15-8
147.
Allhoff F 《The American journal of bioethics : AJOB》2005,5(6):28-30; discussion W10-3
148.
Contrasting linguistic and nonlinguistic processing has been of interest to many researchers with different scientific, theoretical,
or clinical questions. However, previous work on this type of comparative analysis and experimentation has been limited. In
particular, little is known about the differences and similarities between the perceptual, cognitive, and neural processing
of nonverbal environmental sounds and that of speech sounds. With the aim of contrasting verbal and nonverbal processing in
the auditory modality, we developed a new on-line measure that can be administered to subjects from different clinical, neurological,
or sociocultural groups. This is an on-line task of sound to picture matching, in which the sounds are either environmental
sounds or their linguistic equivalents and which is controlled for potential task and item confounds across the two sound
types. Here, we describe the design and development of our measure and report norming data for healthy subjects from two different
adult age groups: younger adults (18–24 years of age) and older adults (54–78 years of age). We also outline other populations
to which the test has been or is being administered. In addition to the results reported here, the test can be useful to other
researchers who are interested in systematically contrasting verbal and nonverbal auditory processing in other populations. 相似文献
149.
150.
Linguistic background has been identified as important in the perception of pitch, particularly between tonal versus nontonal languages. In addition, a link between native language and the perception of musical pitch has also been established. This pilot study examined the perception of pitch between listeners from tonal and nontonal linguistic cultures where two different styles of music originate. Listeners were 10 individuals born in China who ranged in age from 25 to 37 years and had spent on the average 30 mo. in the USA and 10 individuals, born on the Indian subcontinent, who ranged in age from 22 to 31 years, and had spent an average of 13 mo. in the USA. Listeners from both groups participated in two conditions. One condition involved listening to a selection of music characteristic of the individual's culture (China, pentatonic scale; Indian subcontinent, microtones), and one condition involved no music. All listeners within each condition participated in two voice pitch-matching tasks. One task involved matching the lowest and highest pitch of tape-recorded voices to a note on an electronic keyboard. Another task involved matching the voice pitch of tape-recorded orally read words to a note on the keyboard. There were no differences between the two linguistic groups. Methodological limitations preclude generalization but provide the basis for further research. 相似文献