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961.
The stability of individual differences has important implications for understanding the origins of gender-typed behaviors. For example, if some children have a stronger preference for same-sex playmates (gender segregation) than do others, then exploring characteristics that may differentiate these children from their peers (e.g., preference for gender-typed toys or teacher proximity) should prove fruitful. Otherwise, research might be focused more appropriately on group-level processes or situational factors rather than individual differences. In the current study, 57 2 1/2- to 3-year-olds from middle-class Canadian homes were observed repeatedly during free play at their preschools. Four aspects of gender typing (gender segregation, use of masculine and feminine gender-typed toys, teacher proximity) were measured so that the stability of individual differences and relations among the measures could be assessed. Stable individual differences were found for all four measures among boys, and for two of the measures (feminine toy play, teacher proximity) among girls. In addition, boys who played most frequently with masculine toys rarely were observed in proximity to the teacher. However, there was no relation between gender segregation and the other indices of gender typing.  相似文献   
962.
Summary Low-level motor control is defined as adapting an organism to the unique physical properties of its own limbs. The two-jointed arm serves to exemplify that effective low-level motor control demands a neurally mediated inversion of the dynamics, as well as of the kinematics, of a limb system. Reflex-like processing — that is, feedforword of either actual or predicted proprioceptive signals —is thereby assumed to be the principle of the dynamics control. As regards speech-motor control, the overall tool transformation is assumed to transform the force pattern of the articulatory muscles into speech sounds. Like the arm model, the vocal-tract transformation thus defined is also divided into two parts, namely the transformation relating the muscle forces to the mechanospatial states of the vocal tract (which is analogous to the forward dynamics including natural interarticulatory couplings), and the transformation relating the mechanospatial states to the speech sounds. Low-level speech-motor control, then, needs to invert both transformations, each of which can be learned by means of the self-imitation algorithm. Erroneous learning can fail to decouple interarticulatory coupling and therefore lead to abnormal feedback loops through the reflex-like operating neural network, which in turn can cause stuttering if audiophonatoric coupling is involved in learning.  相似文献   
963.
Summary We investigated the hypothesis that the detection of a scene segmentation is facilitated when coincident with a segmentation in another visual dimension. We measured the percentage of the correct detection of horizontal or vertical tritanopic color segmentations perpendicular to, or coincident with, segmentations produced by a subjective-contour stimulus. We found that color discrimination improves when the color segmentation is coincident with the segmentation formed by the subjective contour.In a second experiment, using a yes-no procedure, we found that sensitivity for the detection of luminance segmentations coincident with subjective-contour segmentations increased. However, the detectability of luminance segmentations coincident with a line deteriorated (the gap effect). We conclude that the notion of facilitated detection of coincident segmentations has several problems that undermine its intuitive appeal.  相似文献   
964.
This study examines how gender is related to self-evaluations of information to discuss current social and political issues. The sample is one of predominantly white (96%) college graduates. Using alumni samples, we look at how members of four classes that span 20 years evaluate their knowledge to hold conversations on a variety of public affairs issues ranging from the Strategic Defense Initiative to government funding of abortion. We find gender differences, with men perceiving themselves more knowledgeable in conversations and women less so. We raise the possibility that they are “doing gender.” The implications of these findings are explored.  相似文献   
965.
An experiment was conducted to determine how visual attention is allocated in response to pairwise combinations of location, color, and size cues. Subjects viewed displays of eight letters arranged into an 'X' pattern emanating from a central fixation point. The letters varied on the dimensions of location (foveal or parafoveal positions), size (large or small), and color (red or blue). Seven of the letters were 'X's and the remaining, critical letter was either an 'R' or an 'L'. Subjects were given advance cues about characteristics of the critical letter on two of the three dimensions (location size, and color). The cues varied in their validity such that on any trial either both dimensions were validly cued, one dimension was validly cued while the other was invalidly cued, or both cues were invalid. Subjects were instructed to try to use the cues to find the critical letter, and response times to identify it as an 'R' or an 'L' served as the main dependent measure. Two models were evaluated against the data; in one, location cues are viewed as having distinct effects on an early stage of attention whereas color and size cues operate only in a later, selection stage. In the other model, all cues are used in a similar way to select display items for serial, focal attention. In general, the serial processing model provides a more complete account of the data.  相似文献   
966.
A series of experiments on intersensory facilitation demonstrates that non-informative sound of low to moderate intensity (30/80 dB) facilitates the reaction to a visual stimulus. By manipulating the preprocessing and perceptual stages of the visual signals, it appears that auditory intensity reduces choice reaction time independently from the positive influence of the intensity and duration of the visual imperative signal, but interacts with the effect of stimulus degradation. Degraded stimuli take more profit of the sound than intact stimuli. Besides a short-term activation effect, originated by accessories of the auditory modality, on the motor adjustment stage (cf. Sanders 1983), the results suggest that the accessory influences the stage of feature extraction.  相似文献   
967.
B F Corder  R Whiteside 《Adolescence》1990,25(98):343-357
The application of various types of techniques for structuring the interchange and feedback process in adolescent psychotherapy groups is described. Techniques include random assignment of "roles" for each member during sessions, "parent hot seat" exercises, group goal booklets, and negotiation exercises. These have proved helpful in ensuring effective group participation, providing practice in social skills and verbalization of feelings, and in the development of other specific mastery skills.  相似文献   
968.
Social skills and depression in adolescent suicide attempters   总被引:3,自引:0,他引:3  
The relationship among depression, social skills, and suicidal behavior was examined in a sample of 41 adolescents hospitalized in a general medical setting following a suicide attempt. These subjects were compared to 40 nonsuicidal psychiatrically hospitalized adolescents. Level of depression, assessed using the Children's Depression Inventory (CDI), and social skills, assessed via the Matson Evaluation of Social Skills with Youngsters (MESSY), were evaluated for all subjects. The suicide attempters and psychiatrically hospitalized patients were not found to differ on either the CDI or MESSY. However, multiple regression analyses revealed the factor scores of the MESSY to be related to depression in both patient groups. The data provide support for the relationship between social skills and depression. Results are also discussed in terms of the similarities between adolescent suicide attempters and nonsuicidal psychiatrically disturbed adolescents.  相似文献   
969.
The size of the perceptual unit used in reading was addressed using the predesignated target paradigm. Sixteen subjects viewed the following stimuli in random order: the words tee, the, tie, and toe; the nonwords eet, eht, eit, and eot; and the letters e, h, i, and o. Subjects fixated on the location of the center letter and identified the letter as e, h, i, or o, alternatives which were known to them at the onset. A word superiority effect was obtained for the common word the but not for the less common words tee, tie, and toe. The word superiority effect was attributable to bias rather than discriminability: Subjects exhibited a bias to perceive the words in this experiment as the (i.e., there was a bias to perceive h in the t e stimulus presentations). These results suggest that the common word the is processed in reading units that are larger than the letter, and that the system is biased to perceive common rather than uncommon words in data-limited conditions.  相似文献   
970.
Infantile Colic is a behavioral syndrome characterized by paroxysms of excessive crying and increased motor activity, hypertonicity of the musculature, excessive flatus and erratic sleeping and feeding patterns. Ten to 40% of all infants are diagnosed as having Colic. The medical evidence to date does not justify any conclusions regarding the etiology or treatment of Colic. Typically, parents are advised to simply wait until Colic has run its course which is often 3-4 months. The behavioral program reported here was designed to increase behavior that competed with crying by reinforcing quiet alertness with music and parental attention. Concurrently, it attempted to inhibit excessive crying by a brief time-out procedure. A group of 8 infants diagnosed as Infant Colic were included in this study. The dependent variable, crying, was measured through direct observations based on hourly samples involving 30 observations of 2-min intervals. The independent variable consisted of a behavioral treatment package. A within-S reversal design was used to assess the functional properties of the treatment. The results show that across all 8 infants the introduction of the treatment package led to a substantial decrease in excessive crying of about 75% of the initial baseline. Further, a functional relationship was identified between the treatment and excessive crying behavior: crying decreased when the treatment was initially introduced, it resumed when the treatment was withdrawn and decreased again when the treatment was reinstated.  相似文献   
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