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441.
Fripp D Owen C Quintana-Rizzo E Shapiro A Buckstaff K Jankowski K Wells R Tyack P 《Animal cognition》2005,8(1):17-26
Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely. 相似文献
442.
Mood-congruent attentional bias in dysphoria: maintained attention to and impaired disengagement from negative information 总被引:1,自引:0,他引:1
Attentional bias to negative information has been proposed to be a cognitive vulnerability factor for the development of depression. In 2 experiments, the authors examined mood-congruent attentional bias in dysphoria. In both experiments, dysphoric and nondysphoric participants performed an attentional task with negative, positive, and neutral word cues preceding a target. Targets appeared either at the same or at the opposite location of the cue. Overall, results indicate that dysphoric participants show maintained attention for negative words at longer stimulus presentations, which is probably caused by impaired attentional disengagement from negative words. Furthermore, nondysphoric participants maintain their attention more strongly to positive words. These results are discussed in relation to recent developments in the pathogenesis and treatment of depression. 相似文献
443.
Lissek S Baas JM Pine DS Orme K Dvir S Rosenberger E Grillon C 《Emotion (Washington, D.C.)》2005,5(4):396-407
Sensation seeking (SS) has traditionally been viewed as a phenomenon of the appetitive motivational system. The limited SS research exploring contributions from the aversive motivational system reveals greater anxious reactivity to dangerous activities among low sensation seekers. The present study extends this line of work by comparing levels of fear and anxiety during anticipation of predictable and unpredictable aversive stimuli across high- and low-SS groups. Low sensation seekers displayed greater fear-potentiated startle (FPS) to predictable aversive stimuli, and only those low on SS showed FPS and skin conductance response effects during experimental contexts in which aversive stimuli were delivered unpredictably. Findings implicate enhanced apprehensive anticipation among those low on SS as a potential deterrent for their participation in intense and threatening stimulus events. 相似文献
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447.
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
448.
We provide objective data concerning the age of acquisition (AoA) of words from 202 Italian children 34–69 months of age.
We investigated picture naming with 80 concrete words belonging to eight semantic categories that are included in a widely
used battery for the study of naming and semantic memory. For each word, we calculated three different indices: two directly
expressing the age at which a picture was given the correct name by at least 75% of the subjects, and one expressing the overall
percentage of our children who were correct in the task. (For the latter index, we provide separate values for boys and girls.)
The correlation between objective indices of AoA and adult estimates culled from the literature was not very high. Moreover,
objective indices showed low correlations with frequency and familiarity, in contrast to adult ratings. We conclude that adult
estimates of AoA present validity problems and should be used with caution. The full set of stimuli is available at www.psychonomic.org/archive. 相似文献
449.
Acceptance of cosmetic surgery: scale development and validation 总被引:4,自引:1,他引:3
We conducted a set of four studies with a total of 1288 adult and undergraduate women and men to develop the Acceptance of Cosmetic Surgery Scale. These studies provide evidence of this scale's reliability, as well as convergent and discriminant validity. Initial explorations using this 15-item scale indicate that acceptance of cosmetic surgery is negatively related to satisfaction with physical appearance and positively related to attitudes about make-up use. The acceptance of cosmetic surgery may be more related to fears about becoming unattractive than to hopes of becoming more attractive. Cosmetic surgery attitudes were positively related to age for women but not for men. The study's limitations and implications are discussed. 相似文献
450.
This meta-analysis of eating disorder prevention programs found that intervention effects ranged from an absence of any effects to reductions in current and future eating pathology. Certain effects persisted as long as 2 years and were superior to minimal-intervention control conditions. Larger effects occurred for selected (vs. universal), interactive (vs. didactic), and multisession (vs. single session) programs; for programs offered solely to females and to participants over age 15; for programs without psychoeducational content; and for trials that used validated measures. The results identify promising prevention programs and delineate sample, format, and design features that are associated with larger effects, but they suggest the need for improved methodological rigor and statistical modeling of trials and enhanced theoretical rationale for interventions. 相似文献