Right hemisphere comprehension of verbs in patients with complete forebrain commissurotomy: Use of the dichotic method and manual performance

The paradigm of dichotic listening was used to investigate verbal comprehension in the right, so-called “nonverbal,” hemisphere. Verbal commands were presented to the right and left ears in the simultaneous (dichotic) paradigm. There were striking instances, especially when the left hemisphere was occupied with some extraneous task, in which the right hemisphere understood the verbal command and executed the appropriate motor responses. In those instances the left hemisphere gave no overt response. Although the left hemisphere was usually dominant, it can be nevertheless concluded that not only can the right hemisphere understand verbal commands but can also express itself manually by executing actions more complex than object retrieval or pointing. As has been known for some time, the blockage of the ipsilateral pathway seems so complete during dichotic listening in the commissurotomy patient that there is no report of the words in the left ear—only of those presented to the right. At the same time there is normal report when words are presented to the left ear alone. It was found in the present study, however, that this model is too simple and only applies to the verbal response paradigm of dichotic listening. Under circumstances of dichotic presentation where the stimulus in the left ear (ipsilateral pathway) is necessary or important to the left hemisphere for completing a task, words from both pathways are reported. One may conclude that there exists a gating mechanism in each hemisphere that controls the monitoring of each auditory pathway and the degree of ipsilateral suppression.     

Causal attributions and information seeking to explain success and failure

Previous studies of attributions for success and failure have relied upon a theoretically derived set of causal attributions, either luck versus skill (derived from Rotter, 1966) or ability, effort, luck, and task difficulty (Weiner et al., 1971; Weiner, 1972). The same tendency of relying upon a set of logically derived cues has been evident in investigations of information-processing in making attributional judgments for success and failure (e.g., Fontaine, 1972; Frieze & Weiner, 1971). Two studies were conducted which employed an open-ended format to determine the relevance of the causal categories and information which have been utilized in previous studies. Results of these studies supported the validity of previously employed causal categories and information cues as well as establishing other important but previously ignored causes and sources of information.     

Tests that discriminate between dyslexic and other learning-disabled boys

Dyslexic and nondyslexic boys within a single community's learning-disabled class were given a set of tests; performance on each of these tests has been reported to be significantly impaired in other dyslexic children compared to learning-disabled and normal groups. Linear discriminant function analysis revealed that error types rather than levels of performance best separated the carefully matched learning-disabled groups. Slow naming and high percentage of “dysphasic” errors characterized dyslexic boys. Visual temporal-spatial matching and “configuration-deficient” perceptual errors characterized the adequate readers who have other learning disabilities.     

Behavior modification in education: Contributions and limitations

Behavior modification has been applied widely in educational settings encompassing a wide range of student populations, ages, and areas of focus. Major contributions of behavior modification include development and evaluation of a large number of techniques with extensive classroom research. As a direct consequence of technique development, behavior modification has provided teachers with a selection of classroom practices and information regarding their use. Despite the widespread application of behavioral principles in education, several limitations can be identified including the responses that are altered, the emphasis on response consequences, the focus on child performance rather than behaviors of teachers and others, and the lack of maintenance of improvements evident in many programs. Although limitations can be identified within the field, remarkable advances have been made in identifying educational practices that can improve student and teacher behavior. A major limitation in applying behavior modification to education pertains to dissemination and extension of existing techniques to a large number of settings likely to profit their use. The present paper considers various contributions and limitations of contemporary behavior modification and suggests areas for expansion to augment the progress that has been made.     

Selective information use and perseveration in the search behavior of infants and young children

Two experiments examined the early development of selective information use in search. The first experiment tested 9- and 16-month-olds on a modification of Piaget's Stage IV object permanence task. It examined infants' use of information from previous experiences with an object (prior information) and from the most recent hiding (current information) to locate a hidden object. In the second experiment, 2-, $\text{2}\text{1}\text{2}$-, and 4-year-old children received these same sources of information along with new forms of prior and current information: information about the typical locations of objects (location specificity) and verbal information. No systematic perseveration was observed at 9 months, although previous findings related to perseveration were replicated. Perseveration was found at 16 months, but there was also evidence of selectivity at that age. When errors occurred, they tended to be to the prior location, but they were infrequent in comparison to correct searches at the current location. The preschoolers, while continuing to show perseveration, were more consistently selective than the infants. They also showed considerable generality in extending their selectivity to new sources of information.     

Selectivity and strategy in early search

Early information-processing strategies were examined in a study of very young children's search for hidden objects. Sixteen younger children (mean age: 1 year; 11 months) and sixteen older children (mean age: 2;6) received search problems in which observational and/or verbal information about an object's location was provided. The question of primary interest was how they would respond when given two conflicting sources of information, which differed in modality (observational vs verbal) and in currentness. Both younger and older children showed some use of an appropriate strategy of relying on the more current information, although they did not follow it consistently. Children also showed preferential use of observational over verbal information and response biases favoring the middle location. Age differences were found in children's use of verbal information, in the degree to which they benefitted from practice, and in response biases. These results suggested a distinction between two aspects of the development of search: the acquisition of new search skills and the establishment of appropriate priorities among skills already in the child's repertoire.     

Developmental changes in face processing: results from multidimensional scaling

Multidimensional scaling procedures were used to investigate developmental changes in the ability to process previously unfamiliar faces. Eighty male subjects, aged 7, 9, 12, or adult, rated the similarity of pairs of faces. The faces were presented to subjects in either the upright or the inverted orientation. Multidimensional scaling analyses suggest that subjects of all ages use similar information in judging the similarity of faces. However, for upright faces, individual subjects under age 10 seem to use fewer features at a time. The results argue against a qualitative shift in face processing at age 10, and suggest that the improvement in face recognition ability noted at this age is due at least in part to an increased ability to consider more features simultaneously.     

Does recognition memory improve with age?

In order to test the hypothesis that recognition is a developmentally stable component of the memory system, age differences in recognition of faces were examined while controlling for nonmemory factors that might contribute to differences between the groups. Three groups of children (mean ages: 3 years, 4 months; 4 years, 9 months; and 6 years, 11 months) and a group of college students were tested on a recognition task and a similar matching task. The results indicated no change in recognition across the preschool years but an improvement from the later preschool period to the first grade. Further analyses indicated that this improvement was not due to changes in decision criteria or perceptual skills. These findings call into question the view that recognition is a developmentally invariant component of the memory system.     

Age differences in memory span

Five-year-olds recalled fewer items than adults in memory-span tasks involving both familiar and unfamiliar faces. This occurred even though the use of rehearsal and recoding strategies was minimized for adults. This residual age difference may be partially accounted for by two further processing limitations in children. The five-year-olds needed more time than adults to name a face (Experiment 1) and to encode a face (Experiment 2). In order to test whether limitations in children's initial recognition and stimulus-identification processes could account for recall performance, Experiment 3 reduced adults' exposure duration in the memory-span task. This led to a drastic reduction in the age difference. Other factors contributing to remaining age differences included adults' adaptability in using various alternative encoding and retrieval strategies which elevated their recall performance.