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121.
Two experiments were conducted to examine the effect of absolute-pitch possession on relativepitch processing. Listeners attempted to identify melodic intervals ranging from a semitone to an octave with different reference tones. Listeners with absolute pitch showed declined performance when the reference was out-of-tune C, out-of-tune E, or F#, relative to when the reference was C. In contrast, listeners who had no absolute pitch maintained relatively high performance in all reference conditions. These results suggest that absolute-pitch listeners are weak in relative-pitch processing and show a tendency to rely on absolute pitch in relative-pitch tasks.  相似文献   
122.
This paper describes the use of a custom-configured computer-controlled firearms training simulator to measure perception response (reaction) time (RT) to a stimulus in which the degree of threat presented is a manipulable variable across trials. The computer records the number of frames of videotape traversed between the point of presentation of the threat in the video stimulus and the point at which the subject responds by drawing the firearm. For the purposes of data analysis, these frame-count measures are converted to RT measurements. Example data are presented that capture perception RT at both thedraw-stimulus and thefire-stimulus points in situations for which either only one threat or more than one threat exists. Other elements, such as degree of threat and accuracy of response, provide additional data.  相似文献   
123.
The purpose of the present study was to compare the oculomotor behavior of readers scanning meaningful and meaningless materials. Four conditions were used—a normal-text-reading control condition, and three experimental conditions in which the amount of linguistic processing was reduced, either by presenting the subjects with repeated letter strings or by asking the subjects to search for a target letter in texts or letter strings. The results show that global eye-movement characteristics (such as saccade size and fixation duration), as well as local characteristics (such as word-skipping rate, landing site, refixation probability, and refixation position), are very similar in the four conditions. The finding that the eyes are capable of generating an autonomous oculomotor scanning strategy in the absence of any linguistic information to process argues in favor of the idea that such predetermined oculomotor strategies might be an important determinant of eye movements in reading.  相似文献   
124.
The accreditation standards outlined in the article are used by the International Association of Counseling Services, Inc., as the basis for the formal accreditation of college and university counseling programs throughout the United States and Canada. They reflect the program elements and practice standards that are deemed essential in a counseling center that provides high-quality services to students.  相似文献   
125.
We investigated the ability to match finger orientation to the direction of the axis of rotation in structure-from-motion displays. Preliminary experiments verified that subjects could accurately use the index finger to report direction. The remainder of the experiments studied the perception of the axis of rotation from full rotations of a group of discrete points, the profiles of a rotating ellipsoid, and two views of a group of discrete points. Subjects’ responses were analyzed by decomposing the pointing responses into their slant and tilt components. Overall, the results indicated that subjects were sensitive to both slant and tilt. However, when the axis of rotation was near the viewing direction, subjects had difficulty reporting tilt with profiles and two views and showed a large bias in their slant judgments with two views and full rotations. These results are not entirely consistent with theoretical predictions. The results, particularly for two views, suggest that additional constraints are used by humans in the recovery of structure from motion.  相似文献   
126.
Using a two-stimulus reaction time paradigm, with two separate reward conditions (contingent and noncontingent), we compared slow wave brain potentials (ERPs) in 144 children with attention deficit disorder (ADD) and 30 normal control children. This article reviews the findings during the 900 msec visual warning stimulus. As we had expected, based on ERP work of Forth and Hare (1989) and Raine, Venables and Williams (1990), and on previous work from our own laboratory, the group differences were found in the negative slow wave portions of the ERP complex during the contingent reward condition but not during the noncontingent condition. Aggressive hyperactive subjects with attention deficit disorder (ADDHA) were discriminated from nonaggressive subjects (including control subjects) during the contingent reward condition in the following ways: (1) greater fronto-central negativity (640–900 msec slow wave) and (2) greater right parietal than left parietal negativity (430–750 msec slow wave). All ADD subgroups, when compared to control (CONTR) subjects, showed greater slow wave negativity (700–900 msec) at the midline occipital electrode site during the contingent reward condition. This could be explained in part as an IQ effect on ERPs reflecting the IQ difference between the ADD subgroups and the controls. These slow wave findings seem to relate to attentional problems of these children. They are discussed in terms of a psychobiological model of inhibition/disinhibition and appetitive activation.  相似文献   
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129.
The purpose of the study is to investigate the influence of initial projection of the centre of gravity (CG) on the spatial and temporal organization of the dynamic phenomena accompanying a voluntary movement in humans. From a horizontal quadrupedal stance, ten normal subjects were instructed to raise the right forelimb towards a support target in self paced velocity conditions. Three experimental conditions were tested for which the initial CG projection was either within (C1), at the limits of (C2) or outside the supporting triangle (C3). The results showed that vertical force variations on the four supports always preceded the first vertical displacement of the right wrist (onset of the movement). From C1 to C3, the duration of these anticipatory dynamic phenomena increased enabling an adjustment of the CG position such that equilibrium constraints were fulfilled. For all conditions, the acceleration peak of the CG occurred prior to the onset of movement and from C1 to C3, its magnitude increased in a single direction of the horizontal plane. For each condition, the load transfer was directed to the left forelimb and the right hindlimb (diagonal strategy) and reached a maximal value at the time of lift-off. With respect to this moment, the onset of the movement occurred increasingly early from C1 to C3. These results suggest that contribution of peripheral cues to postural control is more important, when the requirements of horizontal CG displacement increase.  相似文献   
130.
This article briefly reviews behavioral fluency and its 10 products. Fluency development requires three of the four free-operant freedoms: the freedom to present stimuli at the learner's rhythm, the freedom to form the response, and the freedom to speed at the learner's maximum frequency. The article closes with several suggestions that fluent performing is really operant response-response (R-R) chaining, and recommends further controlled laboratory research on free-operant R-R chaining.  相似文献   
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