Rememberings

Philosophical Studies -     

Language characteristics of black children: Implications for assessment

After delineating a number of phonological and syntactic characteristics of black English a review of recent comparative studies is presented. The authors conclude that, while evidence is mixed concerning the question of whether whether a language deficit exists among the lower-class balck children along with a dialect difference, there is clear evidence of the existence of a dialect. The problem facing educators is that no standardized tests have been developed for use with speakers of the dialect. The authors conclude that the use of available tests with dialect speaking children may result in gross errors in educational placement of these children.     

Improvement strategies in free-throw shooting and grip-strength tasks

Participants performed a free-throw shooting task and a grip-strength task before and after imagery, nonspecific arousal, or no instructions. Imagery improved performance in the free-throw shooting task, which is assumed to have more cognitive components than the grip-strength task. Imagery did not improve performance in the grip-strength task, which is assumed to have fewer cognitive components than the free-throw task. Nonspecific arousal, on the other hand, improved performance in the grip-strength task but not in the free-throw shooting task. Athletic experience, confidence levels, and gender were correlated with actual performance levels in both tasks, but not with improvement. Results are discussed within the transfer-appropriate processing framework.     

An object-based cost of visual filtering

Although evidence for object-based attention has been reported in a variety of paradigms, few studies have examined directly the relationship between efficiency in the processing of targets and the number of intervening distractors. In five experiments, observers judged whether the vertices of two relevant shapes were of the same height. Experiments 1 and 2 manipulated observers' perceptual set so that identical stimulus displays were perceived as containing either intervening or flanking distractors. The observers were faster when the distractors were flanking rather than intervening between the targets. Experiments 3-5 varied the number of intervening distractors directly. The observers' response latencies correlated positively with the distractor set-size. Because the distractors were highly discriminable from the targets and the spatial separation between the targets and their interactions with the adjacent distractors were held constant, it was unlikely that the differential reaction times across the conditions were caused by lateral inhibition or response competitions from the distractors. The results suggest the existence of an object-based filtering cost. The implications of the present data for attentional selection over noncontiguous regions are also discussed.     

The modality-specific and -nonspecific components of long-term priming are frequency sensitive

Five experiments were carried out to test the claim that the modality-specific and modality-nonspecific components of long-term priming are differentially sensitive to word frequency, with the specific component being less affected. In contrast with this claim, specific and nonspecific priming were similarly reduced for high-frequency words in three lexical decision and two perceptual identification experiments. These findings highlight the important role of frequency in modulating priming as well as provide a basic constraint for future theories of priming. In addition, the roles of task and student population in modulating priming are examined.     

Orthography plays a critical role in cognate priming: Evidence from French/English and Arabic/French cognates

A series of three experiments was carried out in order to better characterize the representations that support long-term cognate priming. In Experiment 1, robust priming was obtained between orthographically similar French/English cognates in bilingual speakers, and this priming was mediated, in part, by orthographic codes, given that priming for these items was dramatically reduced following a study-test modality shift. In Experiment 2, no priming was obtained between the same set of French/English cognates in monolingual English speakers. Finally, in Experiment 3, priming for orthographically unrelated Arabic/French cognates was no larger than cross-modal priming, suggesting that these effects were mediated by nonorthographic representations. The role of orthography in supporting cognate priming is discussed.     

Perceiving binocular depth with reference to a common surface

A common surface is a spatial regularity of our terrestrial environment. For instance, we walk on the common ground surface, lay a variety of objects on the table top, and display our favorite paintings on the wall. It has been proposed that the visual system utilizes this regularity as a reference frame for coding objects' distances. Presumably, by treating the common surface as such--i.e. an anticipated constant--the visual system can reduce its coding redundancy, and divert its resources to representing other information. For intermediate-distance space perception, it has been found that absolute distance judgment is most accurate when a common ground surface is available. Here we explored if the common surface also serves as the reference frame for the processing of binocular-disparity information, which is a predominant cue for near-distance space perception. We capitalized on an established observation where the perceived slant of a surface with linear binocular-disparity gradient is underestimated. Clearly, if the visual system utilizes this incorrectly represented slant surface as a reference frame for coding the objects' locations, the perceived depth separation between the objects will be adversely affected. Our results confirm this, by showing that the depth judgment of objects (two laterally separated vertical lines) on, or in the vicinity of, the surface is underestimated. Furthermore, we show that the impact of the common surface on perceived depth separation most likely occurs at the surface-representation level where the visual surface has been explicitly delineated, rather than at the earlier disparity-processing level.     

Vertical and bisection bias in active touch

We investigated the conditions that underlie the vertical and bisection illusion in touch, in order to understand the basis of their similarity to visual illusions, and the means of reducing the biases in length perception by active touch. Movement, speed, and spatial reference cues were tested. Movements in scanning L-shapes in ipsilateral and contralateral (across the body midline) table-top space produced significant underestimation of the vertical line with the right hand, but not with the left hand. Right-handed scanning of L-shapes showed no significant bias when the vertical line in the figure was aligned to the body midline, suggesting that spatial cues were involved. The vertical line was overestimated in inverted T-shapes, but underestimated in rotated T-shapes, implicating line bisection. Holding scanning latencies constant reduced the vertical error for inverted T-shapes, but could not explain the bisection bias. Sectioning biases were predicted by the location of junctions on sectioned lines, showing that junction points act as misleading anchor cues for movement extents. The illusion was significantly reduced when reference information was added by instructing subjects to relate two-handed scanning of the figure to an external frame and to body-centred cues. It is argued that disparities in spatial reference (anchor) cues for movement extents are involved in vertical and bisection biases in active touch. The hypothesis that length illusions depend on disparities in spatial reference information can also account for the similarity of the tactile to the visual horizontal-vertical illusion.     

Contrasts and correlations in effect-size estimation

This article describes procedures for presenting standardized measures of effect size when contrasts are used to ask focused questions of data. The simplest contrasts consist of comparisons of two samples (e.g., based on the independent t statistic). Useful effect-size indices in this situation are members of the g family (e.g., Hedges's g and Cohen's d ) and the Pearson r . We review expressions for calculating these measures and for transforming them back and forth, and describe how to adjust formulas for obtaining g or d from t , or r from g , when the sample sizes are unequal. The real-life implications of d or g calculated from t become problematic when there are more than two groups, but the correlational approach is adaptable and interpretable, although more complex than in the case of two groups. We describe a family of four conceptually related correlation indices: the alerting correlation, the contrast correlation, the effect-size correlation, and the BESD (binomial effect-size display) correlation. These last three correlations are identical in the simple setting of only two groups, but differ when there are more than two groups.