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1.
The purpose of this study was to investigate the effects of training on subjects' ability to speechread sentences at varying visual distances of 3-6 ft., 6-12 ft., and 12-18 ft. 15 college women who received training obtained higher sentence speechreading scores than the 15 untrained women. The emphasis placed on kinesthetic feedback may have assisted the trained subjects' performance; however, distance up to 18 ft. did not appear to affect subjects' ability to speechread sentences, regardless of training.  相似文献   

2.
Subjects were tested to assess the distance at which they could recognize the faces of celebrities (more specifically, a set of 44 portrait photographs of movie and television actors). The set of test photographs was shown initially at a distance of 200 ft. and then closer in increments of 20 ft. When the actor in a given photograph was identified, either by name, character role, or by the movie or television show in which the actor had starred, the recognition-distance was recorded and the photograph was removed from the test set. Those which were not recognized (even at the closest distance) were not included in the data summaries or statistical analysis. In calculating recognition-distance for each photograph, the values were adjusted to reflect the distance at which recognition would have occurred if all the faces were of normal size. The upper limit for recognition, as defined by the distance above which only 10% of the faces are identified, was just over 160 ft. for women, and just under 200 ft. for men. There was also a significant difference in mean recognition distance between women and men. The large range of recognition-distance (across photographs and across subjects) argues that the distance is not controlled primarily by the feature detail provided in a given photograph or by the discrimination and recall skills of the observer. More likely it is a function of diverse memory associations, so that the distance at which each photograph is recognized will depend on such factors as frequency and recency of exposure, perceived attractiveness, and how much the subject admires the celebrity.  相似文献   

3.
Ss made magnitude estimations first of the areas, then of the distances, of four circles presented at five distances within an enclosed box 9 ft long. There were three viewing situations: the box had parallel walls, converging walls, or diverging walls. The variations in perspective cues influenced the apparent distance scales: with converging and parallel walls, apparent distance grew as the 1.4 power of physical distance; with diverging walls, it grew as the .95 power. Apparent area was related to distance differently in the three conditions: with converging walls, apparent area increased with distance; with parallel and diverging walls, apparent area decreased with distance. Apparent area was thus not related to changes in physical distance as the apparent distance effects would predict. In each condition, the ratio of apparent area to apparent distance (S′/D′) was a monotonie increasing function of retinal angle θ, but the rate of growth varied among the three conditions. The failure of θ D′ to define a unique value of S′ across conditions indicates that the size-distance invariance hypothesis is inadequate to predict the outcome of this experiment.  相似文献   

4.
Argyle & Dean (1965) predicted that, as the distance increased between a confederate who stared continuously and a naive subject, so the naive subject would increasingly return the confederate's gaze into the eyes. Their findings were held to support the prediction, but Stephenson & Rutter (1970) offered an alternative explanation. They showed that, in the Argyle & Dean situation, observers are increasingly likely with increasing distance to record as gaze directed at the eyes, gaze which is actually directed away from the eyes. In the present experiment, pairs of naive subjects took up positions equidistant from a one-way screen behind which two cameras were located. Each pair held a 5 min. conversation, nine pairs at 2 ft. apart, nine at 6 ft. and nine at 10 ft. The interactions were recorded on videotape, and four observers subsequently scored Looking and Speech from the recordings for each subject independently. By means of zoom lens photography and a ‘split-screen’ recording technique, it was ensured that any relationship between visual behaviour and distance could not be an artifact of observer performance. The results indicated that, while neither the duration of individuals' Looking nor the number of Looks were significantly affected by distance, the two measures of mutual Looking, namely the duration of eye-contact, and mutual focus (the proportion of a pair's Looking which results in eye-contact), both increased with distance.  相似文献   

5.
We aimed to investigate whether an especial skill is present in elite wheelchair basketball players when taking twenty shots with a regular basketball from five different distances (11 ft, 13 ft, 17 ft, & 19 ft) from the basket including the free throw line (15 ft). Twelve elite male basketball players participated. The results showed that as distance increased shot accuracy decreased in line with force by variability predictions for the 11 ft, 13 ft, 17 ft, & 19 ft distances. However, shot performance at the free throw line where players are more familiar with practicing free throw shots did not follow this trend. A linear regression line was drawn to predict performance at the free throw line based on nearer (11 ft & 13 ft) and farer (17 ft & 19 ft) distances to the basket, this was then compared to actual performance. A significant difference between actual and predicted scores was found (p < .05) supporting the presence of an especial skill. Significant positive correlations were found for the 11 ft and 17 ft distance, age, years of playing, and accumulated practice hours with performance at the 15 ft line (p < .05). These correlations imply the operation of generalization in the especial skill. This observation received support from applying a model in which shot accuracy as a function of distance was approximated by two regression lines.  相似文献   

6.
Two groups of 34 Ss each judged the amount of illusion in a three-dimensional Hering figure at three viewing distances (9, 18, and 36 ft). The horizontal bars could be located in the foremost frontal plane of the three-dimensional display or could be recessed within it. Group C-F began at the close distance and Group F-C at the furthest distance. Amount of illusion increased with viewing distance and was greater with the bars recessed within the display. At the furthest distance, but not at the other distances, amount of illusion was greater for Group F-C. The results confirm predictions from Gregory’s theory of primary constancy scaling but are also interpretable in terms of local effects at the intersections of parallel bars and background lines.  相似文献   

7.
This study investigates the underlying mechanism for controlling a dart throw. A single subject threw darts at a standard dartboard in two distance conditions; from 8.5 ft and 7.5 ft. The throwing action of the subject was monitored using the Selspot movement monitoring system. 10 hits (bullseyes), 10 high misses (throws which land in the vertical plane above the bullseye) and 10 low misses (throws which land in the vertical plane below the bullseye) were recorded. Predictions from open-loop, closed-loop and schema models of motor control, regarding the possible patterns of positional variance over time during the throw, are explored. There is an attempt to discover what aspects of the throw determine whether it will hit the target or not and what parameters of the throw are changed to accommodate a different throwing distance. The results are not inconsistent with an open-loop explanation for control of the throw. Given that whether a throw is a hit or not seems to depend on factors probably out of the subjects control, the success of any one throw may be a matter of chance. Rather than parameters of the original throw being re-calibrated to accommodate a new throwing distance a completely new throw is selected.  相似文献   

8.
The extent to which different mechanical baseball-batting devices used during a rest affected performance immediately after rest (warm-up decrement) was examined. Difference scores between the average of prerest Trials 8, 9, and 10 and each of 10 postrest trials were used to determine the presence of warm-up decrement. It was predicted that the use of a batting-T and the Batter's Aid machine (in which a batter swings at a ball popped up within the strike zone) would result in superior performance measured as the distance (ft.) a ball was hit and frequency of contacts on postrest performance reducing or eliminating the warm-up decrement. Performance of 33 boys, aged 11 and 12 yr., indicated that only use of the Batter's Aid eliminated warm-up decrement with respect to both the distance and frequency as compared to the batting-T and control groups. In addition, the batting-T condition solicited significantly better performance than the controls on the distance measure but was statistically similar to the controls in frequency of contacts. Also, superior performance was significantly related to heightened heart rate, a physiological index of arousal. A primary explanation of the results focused on the effects of heightened physiological and psychological arousal on warm-up decrement.  相似文献   

9.
The authors investigated the effects of movement time and movement distance on the information entropy and variability of spatial and temporal error in a discrete aiming movement. In Experiment 1, the authors held movement distance (100 mm) constant and manipulated 11 movement times (300-800 ms) of 8 participants. In Experiment 2, the authors tested 6 movement distances at 2 given movement times (15-60 mm at 300 ms; 40-240 mm at 800 ms) in 8 participants. The variability and entropy for spatial error increased with average movement velocity, whereas the variability and entropy for temporal error decreased as a function of average movement velocity. The common variance between variable error and entropy averaged about 84% and 72% for spatial and temporal errors, respectively, suggesting that the probabilistic approach of entropy reveals features that are not present in the standard deviation index of variability. The findings provide further evidence that information entropy may be a useful single-index representation of variability in the movement speed-accuracy relation.  相似文献   

10.
At a fixed distance of 1.5 ft., varying sizes of vertical lines or circles were presented to S.Subjects estimated either apparent size or distance based on relative size. Estimates of line height and circle diameter yielded power functions with exponents of 0.97 and 0.98, respectively. Distance estimates were curvilinearly related to distance predicted from the size/distance ratio. This result is discussed in terms of non-Euclidean space and in relation to the nature of the judgmental task.  相似文献   

11.
An experiment was designed to determine whether, in the absence of distance-cues, the perceived distance of an object is regulated by the imagined space in which the object is located. Judgements of distance and size were obtained in a completely reduced situation. Preceding these judgements, the subject engaged in 5 min. of visual exploration of the interior of an oblong box. The length of the box differed (3, 6 or 9 ft.) for different groups of subjects. The different pre-exposure conditions were expected to produce diffrences in the dimensions of the imagined space that the subject introduced in the subsequent test session. These differences in imagined space should lead to differences in the perceived distance of a single object located at a constant distance. Significant differences were obtained in the expected direction. In addition, judgements of the size of the standard tended to co-vary positively with the distance-judgments, suggesting that the effect of imagined space on judged distance was not simply the product of experimental biasing of the response system. Some methodological and theoretical implications of the findings are considered.  相似文献   

12.
The present study used a token economy to promote guest greetings by employees at a zoological facility. Guests and confederate guests delivered tokens to zoo employees for making eye contact from 10 ft (3.05 m) away and verbally greeting guests from 5 ft (1.52 m) away (called a 10–5 interaction) and the tokens were exchangeable for small prizes. An ABAB design was used to evaluate the intervention. Results showed increases of 35.3 and 45.0% in correct employee–guest interactions in each intervention phase compared to baseline, thus suggesting that a guest-delivered token economy is an effective way to improve guest greetings. Limitations of the current study and opportunities for future research are discussed.  相似文献   

13.
A dual-task paradigm was used to investigate the time course of attention during putting relative to task difficulty (6 ft vs. 12 ft). Putting performance and reaction time (RT) were measured while 20 experienced golfers responded verbally to an auditory tone presented at 3 probe positions (PP) during the putt: backswing initiation (PP1), backswing peak (PP2), and before impact (PP3). There were 2 significant main effects for putting performance: task difficulty (better performance on the short putt) and probe position (worse performance at PP1 vs. PP3 and Catch Trials). During the short putt, there were no significant differences in RT as a function of PP, indicating that attentional demand remained constant throughout the stroke. RT of the long putt was significantly longer than the short putt, indicating that the long putt required greater attention. Skill level was examined as a potential moderating factor but did not significantly moderate results.  相似文献   

14.
A methodology developed by Cesari and Newell [Cesari, P., & Newell, K. M. (1999). The scaling of human grip configuration. Journal of Experimental Psychology: Human Perception and Performance 25, 927-935; Cesari, P., & Newell, K. M. (2000). The body-scaling of grip configurations in children aged 6-12 years. Developmental Psychobiology 36, 301-310] was used to delineate the roles of an object's weight (W) and distance (D) as well as the actor's strength (S) in determining the macroscopic action used to reach for the object. Participants reached for objects of five different weights placed at 10 distances. The findings of a single discriminant analysis revealed that when object weight is scaled in terms of each individual's strength and reach distance is scaled in terms of each individual's maximum-seated reach distance, a single discriminant analysis was able to predict 90% of the reach modes used by both men and women. The result of the discriminant analysis was used to construct a body-scaled equation, K=lnD+ln(W/S)/36, similar in form to the one derived by Cesari and Newell, accurately predicted the reach action used. Our findings indicate that Cesari and Newell's method can identify a complex relationship between geometric and dynamic constraints that determine the affordances for different reach actions.  相似文献   

15.
This study examined the prevalence of Type D personality and the temporal stability, internal consistency, and construct validity of the DS14 at three time points after myocardial infarction. The prevalence was 14.0% during hospitalization, 25.1% at 1 month, and 19.2% at 12 months. A total of 6.1% of the patients were classified as Type D personality at all three assessments, whereas 68.4% were stable non‐Type D and 25.6% changed between personality classifications. The DS14 had stable structural validity, but low temporal stability over time, especially from hospitalization to the 1‐month and 12‐month follow‐ups (κ = 0.365 and 0.397, respectively).  相似文献   

16.
To investigate the effects of lateral movement on the quality and quantity of catching as they interact with age, 108 children from Kindergarten through Grade 4 were tested. A ramp was constructed which slowed the descent of the 4-in. fleece ball so that it took 1.8 sec. to arrive at the child's location. Each ball could be delivered to one of five different locations in relation to the child. The child practiced five times, with balls coming in a random sequence to each location, the center of the ramp, 1 ft. and 2 ft. each to the right and left of the center. An increase in number of catches made and in the quality of the performance based on McClenaghan and Gallahue's evaluation were associated with grade. The locations 2 ft. from the center produced the fewest catches within a grade, but 1 ft. from center produced more catches from kindergarteners than the center location and occasionally for upper grades. Evaluations of the performances showed a steady improvement across grades, but there was no effect on the evaluation of catching performance of ball location within a grade. Children appear to be at a preferred stage.  相似文献   

17.
An experiment was conducted to determine if duty cycle and off time of tone pulses presented to the comparison ear influence adaptation measured at the opposite (test) ear. Eight subjects were adapted for 5 min to a 1-kHz pure tone at 60 dB SPL. Using a tracking procedure, adaptation was measured under five comparison-signal conditions, each comprised of 1-kHz pulse trains having different on/off times. The on/off times (in milliseconds) were: 200/800 (20% duty cycle); 500/500, 200/200, and 800/800 (50% duty cycle); and 800/200 (80% duty cycle). Adaptation was found to increase as the duty cycle of the comparison tones increased from 20% to 80%. This was evident even when attempts were made to account for the extent to which pulse trains are perceived as softer than continuous signals at the same level (the so-called LOT effect). For the 50%-duty-cycle conditions, similar amounts of adaptation were measured whether the on/off times of the signals were 200, 500, or 800 msec.  相似文献   

18.
This investigation demonstrates a way to innovatively modify the ferritic microstructure at a local scale, particularly at the failure prone area such as Charpy V-notch (CVN) root. Tensile pre-strain (PS) up to 6% and 12% were employed before annealing (An) the samples at 650°C for 15?minutes. Ferrite grain size increased sharply and gradually (along the distance ahead of the notch root) within the microstructurally modified region in 6–12% pre-strained and annealed samples, respectively. The critical strain which promotes strain-induced boundary migration (SIBM), was found to be 0.1 which resulted in abnormally coarse ferrite grains.  相似文献   

19.
Sugars and fats elicit innate and learned flavor preferences with the latter mediated by flavor-flavor (orosensory) and flavor-nutrient (post-ingestive) processes. Systemic dopamine (DA) D1 (SCH23390: SCH) and D2 (raclopride: RAC), but not opioid antagonists blocked the acquisition and expression of flavor-flavor preferences conditioned by sugars. In addition, systemic D1, but not D2 or opioid antagonists blocked the acquisition of flavor-nutrient preferences conditioned by intragastric (IG) sugar infusions. Given that DA antagonists reduce fat intake, the present study examined whether systemic D1 or D2 antagonists altered the acquisition and/or expression of conditioned flavor preferences (CFP) produced by pairing one novel flavor (CS+, e.g., cherry) with a 3.5% corn oil (CO: fat) solution relative to another flavor (CS-, e.g., grape) paired with a 0.9% CO solution. In an expression study, food-restricted rats were trained to drink either flavored 3.5% or 0.9% CO solutions on alternate days. Subsequent two-bottle tests with the CS+ and CS- flavors mixed in 0.9% CO solutions occurred 0.5h after systemic administration of vehicle (VEH), SCH (50-800 nmol/kg) or RAC (50-800 nmol/kg). The rats displayed a robust CS+ preference following VEH treatment (87-88%) the expression of which was attenuated by treatment with moderate doses of RAC, and to a lesser degree, SCH. In an acquisition study, six groups of rats received VEH, SCH (25, 50, 200 nmol/kg) or RAC (50, 200 nmol/kg) 0.5 h prior to 1-bottle training trials with CS+ flavored 3.5% and CS- flavored 0.9% (CS-) CO solutions. A seventh Limited VEH group was trained with its training intakes limited to that of the SCH and RAC groups. Subsequent two-bottle tests were conducted with the CS+ and CS- flavors presented in 0.9% CO without injections. Significant and persistent CS+ preferences were observed in VEH (75-82%), Limited VEH (70-88%), SCH25 (75-84%), SCH50 (64-87%), SCH200 (78-91%) and RAC200 (74-91%) groups. In contrast, the group trained with RAC50 displayed a significant initial CS+ preference (76%) which declined over testing to 61%. These data indicate limited DA D1 and D2 receptor signaling involvement in the expression and acquisition of a fat-CFP relative to previous robust effects for sugar-CFP.  相似文献   

20.
Summary The portrayal of vanishing-point distances in visual imagery was examined in six experiments. In all experiments, subjects formed visual images of squares, and the squares were to be oriented orthogonally to subjects' line of sight. The squares differed in their level of surface complexity, and were either undivided, divided into 4 equally sized smaller squares, or divided into 16 equally sized smaller squares. Squares also differed in stated referent size, and ranged from 3 in. to 128 ft along each side. After subjects had formed an image of a specified square, they transformed their image so that the square was portrayed to move away from them. Eventually, the imaged square was portrayed to be so far away that if it were any further away, it could not be identified. Subjects estimated the distance to the square that was portrayed in their image at that time, the vanishing-point distance, and the relationship between stated referent size and imaged vanishing-point distance was best described by a power function with an exponent less than 1. In general, there were trends for exponents (slopes on log axes) to increase slightly and for multiplicative constants (y intercepts on log axes) to decrease as surface complexity increased. No differences in exponents or in multiplicative constants were found when the vanishing-point was approached from either sub-threshold or suprathreshold directions. When clutter in the form of additional imaged objects located to either side of the primary imaged object was added to the image, the exponent of the vanishing-point function increased slightly and the multiplicative constant decreased. The success of a power function (and the failure of the size-distance invariance hypothesis) in describing the vanishing-point distance function calls into question the notions (a) that a constant grain size exists in the, imaginal visual field at a given location and (b) that grain size specifies a lower limit in the storage of information in visual images.  相似文献   

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