Binary choice reaction time as a criterion of motor equivalence

In a binary choice situation the two alternative movements may vary in the degree in which they are equivalent in respect to controlling processes and/or structures. With a higher degree of motor equivalence a shorter RT is to be expected. A series of five experiments shows that a movement of a finger of one hand has a shorter latency if the alternative movement with the other hand is of the same form than in case of different forms. There is no evidence of corrsponding effect of using the same or different fingers with both hands. These results indicate that programming of the form of a movement is at least partly independent of the muscles involved in movement execution.     

Perceiving subjective contours during early childhood

The perception of subjective contours in visual displays that characteristically produce them among adults was studied for children between 3 and 6 years. Evidence for visually creating subjective contours was derived in two ways: (a) by means of direct perception, and (b) by means of recognition of the typically completed shape from among members of a matching series. With both procedures, there were significant age-related contours. A majority of 3-year-olds showed at least one instance of figural completion based on direct perception, and their average recognition performance was 60%. By 5 years, all children provided a clear indication that they had completed at least one figure by means of subjective contours, and their recognition accuracy was 100%. The overall findings provide age-related information that must be accounted for by theories of perceptual development; in particular, those dealing with pictorial perception.     

Correlates of syntactic development in kindergartners: Deficiency vs. proficiency

In a search for correlates of oral language deficiency, a sentence imitation task (SOLST) was used to select 20 syntactically deficient and 20 syntactically proficient kindergarten subjects. The groups were compared on a battery of tasks measuring oral language comprehension and production, verbal and nonverbal intelligence, visual-motor skill, manual dexterity, right-ear advantage, reading readiness, and later reading achievement. On 8 of the 11 variables, the delayed group performed significantly less well than the controls, although Pearson correlation coefficients of other measures with measures of syntax were generally low to moderate. Negative correlations of some variables with right-ear advantage raise the possibility of reverse dominance in some of the experimental subjects. In addition, there was confirmation for poor performance on the Stephens Oral Language Screening Test resulting in subsequent reading difficulties.     

A research note on occupational changes for Louisiana urban females, 1960–1970

Occupational distributions for sex and race comparisons for areas of Louisiana are examined through an index of dissimilarity, D, a measure of the percentage of workers who must change occupational categories for the two compared percentage occupational distributions to be the same. In 1960 the more urban the area, the lower the index; indices are higher for blacks for male-female comparisons and higher for females than for males in cross-race comparisons. These patterns hold for 1970, but D decreased for all comparisons, indicating a trend toward similarity in compared occupational distributions, but the ultimate limit is unknown.     

The Ringelmann effect: Studies of group size and group performance

Ringelmann's classic finding—that the addition of co-workers in a rope-pulling task leads to a linear decrement in the individual group member's average performance—was reexamined experimentally. Study I attempted to replicate the effect, using groups of subjects ranging in size from 1 to 6. Performance dropped significantly as group size was increased from one individual to two or to three, but the addition of a fourth, fifth, or sixth member produced insignificant additional decrements; thus, the effect was not linear but curvilinear. Study II was designed to examine possible sources of performance loss, separating the factors of “coordination” and “motivation” loss (Steiner, 1972). The possibility of intermember incoordination was eliminated, while motivation loss remained free to vary: Each experimental subject pulled alone, and in “groups” where he believed there were from one to five other members. Once again, individual performance declined significantly with the addition of the first and second perceived co-worker, but then leveled off for perceived group sizes three to six. Some implications are discussed.     

Prenominal adjective order and visual discrimination in children

Preschool and third-grade children heard prenominal adjective phrases describing an object. Each phrase contained an article, two adjectives and a head noun. The phrases were constructed with either normal or inverted adjective order. Either after a one second delay or immediately following phrase presentation, Subjects were shown pictures of two objects. One of the objects (target) depicted the object described in the noun phrase. The other object differed from the target along the dimensions of color, size, or both color and size. The Subject's task was to select the target object. It was predicted that adjective order would influence perceptual strategies used by the Subjects in the visual discrimination task. Analysis of response time scores showed that adjective order interacted with the relevant discriminative stimuli in the discrimination task. These results were interpreted as support for hypotheses that suggest that linguistic organization can constrain conceptual processing involving nonlinguistic information. The effects of the delay condition provided additional evidence for these hypotheses plus support for an arousal hypothesis.     

Polite responses to polite requests

Indirect requests vary in politeness; for example, Can you tell me where Jordan Hall is? is more polite than Shouldn't you tell me where Jordan Hall is? By one theory, the more the literal meaning of a request implies personal benefits for the listener, within reason, the more polite is the request. This prediction was confirmed in Experiment 1. Responses to indirect requests also vary in politeness. For Can you tell me where Jordan Hall is?, the response Yes, I can — it's up the street is more polite than It's up the street. By an extension of that theory, the more attentive the responder is to all of the requester's meaning, the more polite is the response. This prediction was confirmed in Experiments 2, 3 and 4. From this evidence, we argued that people ordinarily compute both the literal and the indirect meanings of indirect requests. They must if they are to recognize when the speaker is and isn't being polite, and if they are to respond politely, impolitely, or even neutrally.     

Control of selective echolalia via the instatement of a general alternative response

Treatment for echolalic responding has been limited to the training of a small number of correct responses and limited stimulus verbalizations by the experimenter, leaving the possibility that the introduction of novel stimuli could result in the reoccurrence of echolalia. In the present study an 11-year-old severely retarded male's echolalic responding to questions that he could not answer correctly was controlled by instating a general alternative response, “I don't know.” The subject continued to respond correctly to questions that he could answer. indicating that the general alternative response had been appropriately discriminated. A Baseline. Treatment. DRO. Treatment design indicated that the subject's echolalic responding, as well as the appropriate use of the general alternative response, was under experimental control. Generalization of the experimental results to the subject's regular day-care setting was accomplished by having the staff verbally punish all echolalic responses and then restate the question to the subject until a non-echolalic answer had been emitted. Implications of these findings and suggestions for combining previous treatment procedures for echolalia with the general alternative response procedure were offered.     

Organization of short-term verbal memory in language areas of human cortex: Evidence from electrical stimulation

Short-term verbal memory (STVM) performance was measured during electrical stimulation of human left frontal-parietal-temporal cortex, at craniotomy under local anesthesia for the treatment of medically intractable epilepsy. The areas of cortex where stimulation alters language, as measured by object naming, are separate but adjacent to the areas where stimulation alters STVM. There are differential effects of stimulation during input, storage, and output phases of STVM at different cortical sites. These suggest that cortex adjacent to the posterior language area is a site of storage of STVM, while cortex adjacent to anterior language area is involved in retrieval from STVM.     

Language localization and variability

Language localization data from 11 neurosurgical patients undergoing cortical resection for medically intractable focal epilepsy were obtained by mapping with bipolar electrical stimulation at current levels below sensory and after-discharge thresholds, during an object-naming task. The topographical extent of language cortex in an individual subject can be wider than that proposed in the classic maps. Within this zone, language is discretely localized, with different sites variably committed to language as measured by the naming function. The naming data from the left cortex of eight patients, all left-brain-dominant, were pooled to determine the variability within the primary language zone. Only a narrow band of posterior, inferior frontal lobe, immediately anterior to motor strip, showed involvement in all of the patients in whom it was sampled. This is a motor speech area; it constitutes only a small portion of the frontal language area. Other infero-frontal, parietal, and postero-temporal sites showed considerable variability, with naming involvement in only 50–80% of the patients sampled. There is a suggestion that some of these patterns of language localization may correlate with poorer verbal abilities. Data were also obtained on language localization in the left insula in a patient who was left-hemisphere-dominant for language. Mapping of the right hemisphere in a left-brain-dominant patient demonstrated no naming function. Mapping of the right hemisphere in one and the left hemisphere in another patient, both of whom were right-hemisphere-dominant for language, suggests more diffuse language representation with right hemisphere dominance.