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231.
232.
Jaakkola K Fellner W Erb L Rodriguez M Guarino E 《Journal of comparative psychology (Washington, D.C. : 1983)》2005,119(3):296-303
In 2 experiments, bottlenose dolphins (Tursiops truncatus) judged the ordinal relationship between novel numerosities. The dolphins were first trained to choose the exemplar with the fewer number of items when presented with just a few specific comparisons (e.g., 2 vs. 6, 1 vs. 3, and 3 vs. 7). Generalization of this rule was then tested by presenting the dolphins with all possible pairwise comparisons between 1 and 8. The dolphins chose the exemplar with the fewer number of items at levels far above chance, showing that they could recognize and represent numerosities on an ordinal scale. Their pattern of errors was consistent with the idea of an underlying analog magnitude representation. 相似文献
233.
Rivas E 《Journal of comparative psychology (Washington, D.C. : 1983)》2005,119(4):404-417
In light of the controversy about the linguistic properties of chimpanzee signing behavior, the recent sign use of 5 chimpanzees (Pan troglodytes) with long histories of sign use was analyzed while they interacted with longtime human companions. Four corpora from 1992 to 1999 consisting of 3,448 sign utterances were examined. The chimpanzees predominantly used object and action signs. There was no evidence for semantic or syntactic structure in combinations of signs. Longer combinations showed repetition and stringing of object and action signs. The chimpanzees mostly signed with an acquisitive motivation. Requests for objects and actions were the predominant communicative intentions of the sign utterances, though naming and answering also occurred. This recent sign use shows multiple differences with (early) human language. 相似文献
234.
Long-term social isolation of laboratory animals is a model to study the behavioral and neurochemical consequences of the absence of social interaction in rodents. Many of the symptoms induced by isolation resemble depression and anxiety disorder symptomatology. Our studies have revealed that male mice socially isolated for more than 4 weeks, exhibit increased aggressiveness, a reduced responsiveness to GABA(A) receptor acting drugs, and a downregulation of brain levels of 3alpha,5alpha-tetrahydroprogesterone (allopregnanolone: 3alpha,5alpha-THP), a neurosteroid endowed with potent positive allosteric modulatory activity of the action of GABA at various GABA(A) receptor subtypes. This downregulation of 3alpha,5alpha-THP appeared to be associated with the reduction of brain type I 5alpha-reductase mRNA and protein expression. Systemic administration of the selective serotonin reuptake inhibitor fluoxetine and its metabolite norfluoxetine normalized brain 3alpha,5alpha-THP content and reduced responsiveness to GABA(A) mimetic drugs in a stereospecific manner. These drugs in nanomolar doses also reduced social isolation-induced aggressiveness with the same stereospecificity as detected in their action on 3alpha,5alpha-THP brain content, while their ex vivo inhibition of serotonin reuptake occurred at high micromolar doses and lacked stereospecificity. From these results we infer that the brain 3alpha,5alpha-THP content physiologically upregulates GABA(A) receptor responsiveness to GABA and that social isolation induces a reduction of brain 3alpha,5alpha-THP content that is probably causally related to the onset of aggression. 相似文献
235.
Almost all research on aggression in adolescent romantic relationships makes use of 1-time, retrospective assessment methods. In the present research, the authors compared data on the experience of adolescent relationship aggression (physical aggression and threatening behavior) collected from 125 high school students via 2 methods: (a) a 1-time, 2-month retrospective assessment and (b) a cumulative method based on four 2-week retrospective assessments, each spaced 2 weeks apart. For the cumulative method, data from the 4 assessments were aggregated to cover the same time period as the single, 2-month retrospective assessment. A greater proportion of the sample (48.0%) reported experiencing physical aggression using the cumulative method compared with the single, 2-month retrospective method (27.0%). The prevalence of threatening behavior was also higher using the cumulative method (48.8% vs. 24.8%). Adolescent trauma and anxiety symptoms correlated more strongly with physical aggression data derived from the cumulative method than from the 1-time assessment method. 相似文献
236.
Doctor's Expertise and Managing Discrepant Information from Other Sources in Genetic Counseling: A Conversation Analytic Perspective 总被引:1,自引:0,他引:1
The study examines a recurrent interactional pattern in genetic counseling. It describes clinical geneticists' responses in
situations in which clients have presented information from other sources that is potentially discrepant with information
given by the doctor. The data consists of 12 video-recorded sessions of genetic counseling in Finland, and the method is conversation
analysis. There are two primary ways the doctors respond: either they accept the client's information as such, but show that
it is not discrepant with the doctor's information, or they reject the client's information. In the latter case they mitigate
the ‘wrongness’ of the client's information. The clinical geneticists seem to be working with a dilemma: they need to find
a balance between ensuring correct understanding of the information and showing respect for the expertise of others. A particularly
complex case is also analyzed and reflected on. 相似文献
237.
Claes E Evers-Kiebooms G Denayer L Decruyenaere M Boogaerts A Philippe K Legius E 《Journal of genetic counseling》2005,14(5):349-363
This prospective study evaluates emotional functioning and illness representations in 68 unaffected women (34 carriers/34
noncarriers) 1 year after predictive testing for BRCA1/2 mutations when offered within a multidisciplinary approach. Carriers had higher subjective risk perception of breast cancer
than noncarriers. Carriers who did not have prophylactic oophorectomy had the highest risk perception of ovarian cancer. No
differences were found between carriers and noncarriers regarding perceived seriousness and perceived control of breast and
ovarian cancer. Mean levels of distress were within normal ranges. Only few women showed an overall pattern of clinically
elevated distress. Cancer-specific distress and state-anxiety significantly decreased in noncarriers from pre- to posttest
while general distress remained about the same. There were no significant changes in distress in the group of carriers except
for ovarian cancer distress which significantly decreased from pre- to posttest. Our study did not reveal adverse effects
of predictive testing when offered in the context of a multidisciplinary approach. 相似文献
238.
Blindfolded right-handed participants were asked to position, with the right hand, a frontoparallel rod to one of three orientations:
vertical (0°) and left 45° and right 45° obliques. Simultaneously, three different backgrounds were explored with the left
hand: smooth, congruent stripes (parallel to the orientation to be produced), or incongruent stripes (tilted relative to the
orientation to be produced). The analysis of variable errors showed that the oblique effect (higher precision for the vertical
orientation than for the oblique orientations) was weakened in the presence of contextual cues, because of an improvement
in oblique precision. Moreover, the analysis of constant errors revealed that the perception of orientations erred in the
direction of the stripes, similar to the effect that has been found with vision, where visual contextual cues (tilted frame
or lines) divert the perception of the vertical. These results are discussed in relation to a patterncentric frame of reference
hypothesis or as a congruency effect. 相似文献
239.
The authors report differential item functioning (DIF) between Black and White participants completing the 60-item Padua Inventory (PI) for obsessive-compulsive disorder (OCD). The authors use an Internet-generated sample that included 105 Blacks, 67 Hispanics, 582 Whites, and 136 additional participants reporting an OCD diagnosis. Factor analysis replicated prior work indicating the PI consists of four factors: contamination fears, checking behaviors, impaired control over thoughts, and fear of losing control over impulses. On the contamination subscale, nonclinical Black and Hispanic mean scores were as high as the OCD group. Comparing Blacks to Whites, the authors applied an item response theory, DIF-graded response model to each factor and found significant DIF on eight items, with biased items in each factor. Results suggest that extraneous factors contribute to racial differences on scores. Cultural practices and fear of being negatively stereotyped may contribute to item bias. 相似文献
240.
Hazeltine E 《Psychonomic bulletin & review》2005,12(4):682-688
The present study investigated response-response (R-R) compatibility in a bimanual keypressing task. Numeric and spatial stimuli
were used to cue responses for each hand. Two groups of participants differed in terms of the stimulus-response mappings for
the numeric stimuli. For one group, the numeric stimuli were mapped so that the same number for each hand indicated responses
that were anatomically compatible (e.g., index finger of both hands). For the other group, the same number for each hand indicated
responses that were left-right compatible (e.g., leftmost finger of both hands). The spatial stimuli were mapped in a spatially
compatible manner to the responses for both groups. For numeric stimuli, reaction times (RTs) were faster when the same number
indicated the response for each hand, regardless of the mapping. For the spatial stimuli, RTs were determined not only by
the pairing of stimuli or responses, but also by how the responses were indicated by numeric stimuli. The results indicate
that R-R compatibility effects are mediated by abstract codes that reflect individuals’ conceptualizations of their actions. 相似文献