Numerosity discrimination of repetitive visual stimuli by mildly retarded adolescents and normal children.

Compared 20 male and 20 female retarded adolescents with 40 younger normals matched for sex and ma on a visual numerosity task. Sequential light flashes of 300, 500, and 700 msec. Occurring in multiple loci were presented in trains of 3-38 flashes. Error frequency and magnitude scores were significantly (p     

Paired-associate and serial learning in retarded readers.

Exp I examined 68 9-13 yr old retarded readers on a paired associate task using the anticipation method and a serial-learning task using the study-test method. Intratask correlations were highly significant for each task, but intertask correlations were negligible. However, the 2 tasks also differed in difficulty. Exp II, with 27 additional like Ss, tested whether serial learning was easier with the anticipation method and whether paired associate and serial learning performance remained unrelated when difficulty was comparable. Serial learning was significantly easier, scores were comparable to paired associate scores, and most paired associate and serial learning measures were highly correlated. It is concluded that the performance of retarded readers may be determined more by difficulty than by type of task. Anticipation methods may be preferable to study-test methods for such children. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship between level of visual pattern difficulty during rearing and subsequent discrimination in rats.

Each of 3 groups of Sprague-Dawley albino rats (n = 36) was reared with 1 of 3 levels of visual patterns for 50 days and then compared with 36 controls on the ability to discriminate these patterns in a maze. Results indicate that preexposure significantly facilitated subsequent discrimination learning only to the difficult pair of patterns (circle, triangle). Preexposure to intermediate level patterns (, inverted ) and easy patterns (horizontal striations, vertical striations) had no effect. It is suggested that there is some early time period(s) during which patterns can be discriminated and that this preexposure can influence subsequent learning. (18 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance of retarded readers on the WISC and educational tests.

Compared the WISC results of 54 retarded readers of average intelligence from the 6 primary school grades with those of a matched group of 54 adequate achievers (controls). The Ss had greater verbal (V)-performance (P) differences than the controls in both directions. This way due mainly to their significantly poorer performances on Information, Arithmetic, and Coding subtests, and to their significantly better performances on Comprehension, Picture Arrangement, and Block Design subtests after adjustments had been made by covariance analyses for Full Scale IQ differences. The Ss also performed significantly less well than controls on untimed tests of Spelling and Arithmetical Calculation. No tendency was found for the differences between groups on the WISC or educational tests to increase with age, as was the case with their reading achievement. Hence there was no support for D. A. Neville's (see 35:5) hypothesis that certain of the differences are effects of reading retardation rather than correlated symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Infant visual recognition memory: Independent contributions of speed and attention.

Relations between infant visual recognition memory and later cognition have fueled interest in identifying the underlying cognitive components of this important infant ability. The present large-scale study examined three promising factors in this regard--processing speed, short-term memory capacity, and attention. Two of these factors, attention and processing speed (but, surprisingly, not short-term memory capacity), were related to visual recognition memory: Infants who showed better attention (shorter looks and more shifts) and faster processing had better recognition memory. The contributions of attention and processing speed were independent of one another and were similar at all ages studied--5, 7, and 12 months. Taken together, attention and speed accounted for 6%-9% of the variance in visual recognition memory, leaving a considerable, but not unexpected, portion of the variance unexplained. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of item format on item discrimination and difficulty.

Studied the effects of item stem orientation (positive-negative), structure (open-closed), and inclusive alternatives on item difficulty and discrimination. Data were obtained from 1,124 undergraduates taking a regularly scheduled test. Results indicate that item difficulty was critically affected by all 3 independent variables with no interactions and that item discrimination was affected by the use of an inclusive alternative with a significant interaction between orientation and stem structure. Suggestions are made with respect to effective item-writing strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of visual deprivation on depth discrimination of hooded rats.

In a study with hooded rats (N = 530), Ss raised in the dark were compared to light-reared controls. 21-day-old dark-reared (DR) Ss were not different from controls in the discrimination of 4-in depths, but 30-day-old DR Ss were deficient. 60-day-old DR Ss were deficient in discriminating 4-, 6-, and 8-in depths. 30-day-old DR Ss recovered the loss in depth discrimination after 48 hrs in the light. 60-day-old DR Ss had no noticeable recovery to the 4-in depth discrimination, but they did recover discrimination of the 6-in depth after 72 hrs in the light. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding difficulty and memory enhancement for young and older readers.

Memory for text that required active construction (generation) on the part of the reader to comprehend some of the information was examined. (Letters were deleted from the words composing some of the idea units of the text). For both high school students and older adults, idea units that had letters deleted were remembered better than idea units with intact words on a cued-recall test. This pattern held for easier as well as for harder letter deletions. It was concluded that retention of textually presented information can be improved in older adults if the presentation format of the text induces or guides mental operations that support good encoding. Production-deficiency accounts and attentional/resource deficiency accounts of age-related memory decrements are discussed in light of the present results. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neighborhood effects in visual word recognition: Effects of letter delay and nonword context difficulty.

The role of a target's orthographic neighborhood in visual word recognition was investigated in 2 lexical decision experiments. In both experiments, some stimuli had 1 letter delayed relative to the presentation of the rest of the stimulus. Exp 1 showed that delaying a letter position, which yielded a potentially competitive neighbor, was more costly to target recognition than delaying a position that yielded no neighbors. This effect was strongest when one of these neighbors was of higher frequency than the target itself. Additionally, the effect was reduced for words with a high friendly-to-unfriendly-neighbor ratio (friendly neighbors being those words containing the delayed letter). In Exp 2 the difficulty of the word–nonword discrimination was manipulated by varying the density of the nonwords' neighborhoods. Only when the nonwords had many neighbors at several positions did the word responses show neighborhood competition effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Test difficulty, reliability, and discrimination as functions of item difficulty order.

In an attempt to evaluate the often stated rule that test items should be arranged in an increasing order of difficulty, the effect of item difficulty order on total test reliability, difficulty, and discrimination was investigated in a series of 4 experiments. Each experiment involved a comparison of 2 or more tests, containing the same 40 items and differing only with respect to the order of those items. The differently ordered forms did not, in any of the experiments, differ significantly in test difficulty or test reliability. The results with respect to discrimination were not as clear-cut. However, the results tend to lead to the conclusion that item difficulty order on a power test of facts and principles given in the normal college classroom will not significantly affect these 3 test statistics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of luminance on visual evoked potential amplitudes in normal and disabled readers

Adsorption of four 5-pyrazolone derivatives and two carboxylic acids from aqueous solutions was studied. Partition coefficients for the analyzed drugs were calculated. Good corelation between log(k1, k2) (Langmuir constants) and log (octanol-water partition coefficient) of the drugs were found. The higher log(k1k2) value the higher solubility of the non-narcotic and analgetic drugs.     

The effect of psychopathology on visual discrimination.

"Perceptual and motor aspects of the Bender-Gestalt Test performance were compared for 4 groups of Ss: 10 student nurses, 10 acute schizophrenic patients, 10 chronic schizophrenic patients, and 10 patients hospitalized for neurological reasons… . After the Ss had obtained equal experiences with the Bender designs by reproducing them under memory and copy conditions, a perceptual multiple-choice test was administered under memory and matching conditions. Results indicate that there are marked differences in perceptual accuracy between the 4 groups: the control population was most accurate, with the acute schizophrenic, chronic schizophrenic, and neurological patients less proficient in that order." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic interference from visual object recognition on visual imagery.

A new technique for examining the interaction between visual object recognition and visual imagery is reported. The "image-picture interference" paradigm requires participants to generate and make a response to a mental image of a previously memorized object, while ignoring a simultaneously presented picture distractor. Responses in 2 imagery tasks (making left-right higher spatial judgments and making taller-wider judgments) were longer when the simultaneous picture distractor was categorically related to the target distractor relative to unrelated and neutral target-distractor combinations. In contrast, performance was not influenced in this way when the distractor was a related word, when a semantic categorization decision was made to the target, or when distractor and target were visually but not categorically related to one another. The authors discuss these findings in terms of the semantic representations shared by visual object recognition and visual imagery that mediate performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A note on visual recognition thresholds.

60 college students are presented, tachistoscopically, a list of 7 pleasant and 7 unpleasant 5 letter words which had been matched for frequency. All of the words are presented randomly to the subjects for various lengths of time, the Ss recording the word they believe to have been flashed on the screen before them. Significantly fewer errors of recognition are made on the pleasant words than on the unpleasant words. It is concluded that perceptual behavior, here defined as visual recognition thresholds, is influenced by the pleasantness or unpleasantness of the stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race as a visual feature: Using visual search and perceptual discrimination tasks to understand face categories and the cross-race recognition deficit.

One of the most familiar empirical phenomena associated with face recognition is the cross-race (CR) recognition deficit whereby people have difficulty recognizing members of a race different from their own. Most researchers assume that the CR deficit is caused by failure to generalize perceptual encoding expertise from same-race (SR) faces to CR faces. However, this explanation ignores critical differences in the social cognitions and feature coding priorities associated with SR and CR faces. On the basis of data from visual search and perceptual discrimination tasks, it appears that the deficit occurs because people emphasize visual information specifying race at the expense of individuating information when recognizing CR faces. In particular, it is possible to observe a paradoxical improvement in both detection and perceptual discrimination accuracy for CR faces that is limited to those who recognize them poorly. These findings support a new explanation for the CR recognition deficit based on feature coding differences between CR and SR faces, and appear incompatible with similarity-based models of face categories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of case type, word frequency, and exposure duration on visual word recognition

The authors report 4 lexical decision experiments in which case type, word frequency, and exposure duration were varied. These data indicated that there is a larger mixed-case disadvantage for nonwords than for words for longer duration presentations of targets. However, when targets were presented for 100 ms (followed by a postdisplay pattern mask), a larger mixed-case disadvantage occurred for words than for nonwords. For word frequency, the data from Experiments 1, 2, and 3 revealed a slightly larger mixed- case disadvantage for higher frequency words than for lower frequency words. (There was additivity between word frequency and case type for experiment 4.) These results are consistent with a holistically biased, hybrid model of visual word recognition but inconsistent with analytically biased, hybrid models of word recognition, such as the process model (Besner & Johnston, 1989) and the interactive-activation model (McClelland & Rumelhart, 1981).     

Relationship between word difficulty and access of single-word meaning by skilled and less skilled readers.

Previous research, by R. M. Golinkoff and R. R. Rosinski (1976), used a picture-word interference task to show that skilled and less skilled comprehenders in the 3rd and 5th grades could retrieve the meaning of primer-level words equally well. With a similar task and comparable groups of children ( N = 64), the present study assessed the relationship between word difficulty and semantic access by using both the easy words and a new set of more difficult words. Retrieval of the meaning of these difficult words was least apparent for the less skilled 3rd graders, the group that had the most difficulty decoding these words. Results indicate that decoding ease and extraction of word meanings are related and also suggest that decoding ability must be considered a factor in reading comprehension. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of success and failure on the discrimination learning of normal and retarded children.

30 normal and 30 retarded children learned a 3-choice size discrimination following exposure to experimental tasks under conditions of success, failure, or neutrality. Both normal and retarded children learned more quickly following success and failure than under the neutral condition. In a 2nd study, 32 normal and 32 retarded children learned the same criterion task under success or failure conditions. Here, both success and failure again facilitated the performance of both normal and retarded Ss. Also, social responsivity interacted with intelligence and exeprimental conditions in influencing the children's learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of density and format on letter discrimination by beginning readers with different learning styles.

Investigated the processing requirements in letter discrimination for 40 1st graders with reflective-impulsive and field-dependent-field-independent learning styles. Field dependence was measured by the Children's Embedded Figures Test, and impulsivity was measured by the Matching Familiar Figures Test. The discrimination task, presented in vertical and horizontal formats and in high- and low-density arrangements, consisted of matching each of 12 letterlike symbols with 1 of its 12 transformations. Results support all a priori hypotheses: (a) Impulsivity-reflectivity was related only to number of errors and latency. (b) Field dependency-independency was unrelated to latency but interacted with contextual arrangements. Field dependents made more errors than field independents on high-density and horizontal presentations. Interpretations are made in terms of the feature analysis processes employed by beginning readers with different learning styles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Affective tone and visual recognition thresholds.

"These findings clearly confirm the results of those studies that have found no differences in recognition thresholds for stimulus words of purportedly differential affective value when the relative frequency of the stimulus words is controlled." (PsycINFO Database Record (c) 2010 APA, all rights reserved)