Pup retrieving as a reinforcer in nulliparous mice

Six nulliparous female mice were trained to bar press with bar pressing reinforced by the opportunity to retrieve pups to the nest. Then, responses on one bar produced the opportunity to retrieve pups, while responses on a second bar produced sensory contact with non-retrievable pups, presented behind a screen door. All subjects emitted more responses on the bar yielding retrievable pups. When the bar-pup contingency was reversed, five subjects learned to press the opposite bar for retrievable pups. The sixth subject showed extinction of responding on the bar that had previously yielded retrievable pups, but failed to press the other bar. A major portion of the reinforcing value of pup presentation resulted from the opportunity to perform the behavior of pup retrieving. This finding supports theoretical formulations which state that the performance of species-typical consummatory behaviors should have reinforcing properties.     

SKED systems: Paper tape,Tennecomp, and OS/8

The SKED system has been developed at different levels of complexity and power for differing hardware configurations. The simplest of these, and the least expensive, is the paper-tape SKED system. Some of the drawbacks associated with the use of paper tape are absent in the Tennecomp magnetic tape cartridge system. Users with mass storage capabilities can make use of the OS/8 operating system (copyright DEC) to speed up all aspects of the SKED system (especially editing, compilation, and loading of programs), and take advantage of a file-oriented system structure for data storage and analysis.     

NOTE ON SIMULTANEOUS DISCRIMINATION OF VISUAL ATTRIBUTES

van der H eijden A. H. C. Note on simultaneous discrimination of visual attributes. Scand. J. Psychol ., 1972, 13 , 71–72.—A tachistoscopically presented stimulus, provided it is above threshold, results in a visual image with a minimum duration of about 250 msec. In experiments on visual information processing, therefore, the results must be interpreted in terms of 'effective stimulus duration' (exposure time and duration of visual image) rather than exposure time alone.     

On the development of national attitudes in children

The present study consists of three related experiments which are concerned with the development of national attitudes in children between the ages of seven and twelve. It was predicted on the basis of a structural interpretation of Allport's three-stage developmental theory of prejudice that national attitudes will increase at first due to increasing consistency of judgment and decrease afterwards due to cognitive differentiation. The hypothesis is partially confirmed with respect to the attitudes of children towards other countries but not confirmed with respect to the attitudes of children towards people who are perceived as foreigners. A tentative explanation is offered for the last finding. It was shown moreover that the attitudes of older children display more cognitive balance than those of younger children. In connection with the last problem, a quantified modification Bf Heider's theory of balanced states was introduced.     

Measurement of eye orientation of monkeys during visual discrimination

This paper describes apparatus and procedures for measuring eye orientation in the rhesus monkey without restraining the head. The main components of the apparatus are (a) a helmet on which are mounted the discriminative stimuli and the optical and other devices for obtaining a corneal reflection, (bj a special restraining chair that allows the monkey to respond to pushbuttons in front of him, yet prevents him from reaching the equipment mounted on the helmet, and (c) systems for presenting stimuli, monitoring choice responses, and recording eye orientation, which are controlled by a LINC-8 computer. The initial findings on eye orientation during performance on both a hard and an easy brightness discrimination problem are also presented.     

Hemispheric specialization for voice recognition: evidence from dichotic listening

To measure lateralization of voice recognition abilities in normal subjects, listeners identified both the speaker (a famous male) and the word spoken on each trial in a dichotic listening paradigm. The voice identification task resulted in a zero ear advantage, which differed significantly from the significant right ear advantage found for word identification. This suggests that voice and word information, although carried in the same auditory signal, engage different cerebral mechanisms.     

Word identification in reading proceeds from spelling to sound to meaning

Van Orden (1987) reported that false positive errors in a categorization task are elevated for homophonic foils (e.g., HARE for A PART OF THE HUMAN BODY). Two new experiments replicate this finding and extend it to nonword homophone foils (e.g., SUTE FOR AN ARTICLE OF CLOTHING). False positive errors to nonword homophone foils substantially exceed false positive errors to nonhomophonic nonword spelling controls, showing that the phonological characteristics of the nonword foils are critical. Because nonwords are not represented in the lexicon, this new result implicates computed phonological codes as a source of the categorization errors. Additionally, in each of two experiments, matched word and nonword homophones produced virtually identical error rates. If stimulus nonword homophones are viewed as extremely unfamiliar words, compared with the relatively familiar stimulus word homophones, then our failure to observe an effect of stimulus familiarity strengthens the case that phonological coding plays a role in the identification of all printed words. The fact that the results are obtained in a categorization task that requires reading for meaning (rather than a lexical decision task) makes it difficult to avoid the conclusion that phonological mediation plays a role in normal reading of text for meaning.     

Schema anticipation in recall: memory process or report strategy?

Summary This article reports an experimental investigation testing the hypothesis that recall reports are systematically biased by the recaller's knowledge about who is to receive the recall report, while that bias is absent from a recognition test. Subjects listened to one of two versions of a story recounting John's visit to the doctor. After the story was read, subjects were asked to recall the story either with standard-recall instructions or with instructions to recall for peers, for Martians, or for a contest. In a fifth condition, subjects performed a filler activity, viz., the recall of a personal experience. After the recall test subjects were administered a recognition test. Between the groups no systematic differences in memory performance were observed in the recognition test. Recall for peers appeared to be poorer than recall in the other conditions. Subjects in the recall for a contest condition scored higher than the subjects in the other groups. Not only did groups differ with respect to bias, but there were also systematic differences in the memory or discrimination scores. The findings are discussed within the framework of schema theory.