Visual behavior of the young human infant: Relationships between chromatic and spatial perception and the activity of underlying brain mechanisms

Two experiments investigated visual attention in human infants. In one experiment, babies looked longer at more than at less saturated colors. In a second experiment, babies looked longer at gratings aligned along the horizontal and vertical orthogonals than along the obliques. Because saturated colors and orthogonal stimulation elicit greater activity in visual system neurons and greater amplitude evoked potentials than desaturated colors or oblique stimulation, these two experiments support the hypothesis that the simple visual stimuli to which infants preferably attend are those that are particularly appropriate in stimulating the geniculostriate or primary visual system. The ethological significance of this taxic mechanism and its utility and function in perception, cognition, and aesthetics are underscored.     

A test of the self-perception explanation of the effects of rewards on intrinsic interest

An experiment was conducted to test the proposition that rewards undermine or enhance intrinsic interest in a task to the extent that individuals interpret their behavior as being motivated by the reward. It was predicted that when subjects were denied the opportunity to develop and confirm this attribution, rewards would not produce an undermining effect, but rather would enhance dispositions and behavior. Subjects were recruited to evaluate a new sugar-free soft drink. Two levels of incentives (reward-no reward), two levels of examination (opportunity-no opportunity), and three levels of outcome (good-neutral-poor) were employed. The results support the prediction that an incentive's effect depends on the examination opportunity. In the examination condition, rewarded subjects attributed their behavior more to external factors than did unrewarded subjects, but gave more negative product evaluations only after tasting it. In the no examination condition, there were no differences in the attributions made by rewarded and unrewarded subjects, and rewarded subjects were more positively disposed toward the product both before and after tasting it. These results are explained as a consequence of two properties of rewards, enhancement through reinforcement and undermining through discounting, and of hypothesis-testing processes.     

Attitudinal qualities relating to the strength of the attitude-behavior relationship

A study was conducted to examine the relation between each of several attitudinal qualities and attitude-behavior consistency. Subjects' attitudes toward volunterring to participate in psychological research were assessed. The number of experiments in which each subject volunteered to participate was employed as the measure of behavior. Attitude-behavior consistency was significantly related to (1) the amount of direct experience upon which the subject's attitude was based (specifically, the number of experiments in which the subject had previously participated), (2) the degree of certainty with which the attitude was held, and (3) how well-defined the subject's attitude was, as measured by the width of his latitude of rejection. These three attitudinal qualities were significantly intercorrelated, suggesting that direct experience with an attitude object may produce an attitude that is both better defined and more confidently held than an attitude formed through more indirect means.     

The extinction of within-compound flavor associations

Three experiments studied extinction of the associations which are formed between two flavors presented in a simultaneous compound. In Experiment 1 those associations were identified by a sensory preconditioning procedure in which the poisoning of one element of the compound led to the rejection of the other element. Separate presentation of either element between their joint occurence and the poisoning of one element sharply attenuated the rejection of the other element. That attenuation was interpreted in terms of the extinction of within-compound associations. Experiment 2 obtained similar results with an alternative extinction procedure in which the elements of the original compound were presented in other compounds. Experiment 3 obtained similar results when the existence of the within-compound associations was determined by an alternative assessment procedure in which one element of the compound was made more attractive by the induction of a specific hunger. These experiments suggest that within-compound associations can be extinguished when the elements are separately presented outside of the compound. Experiments 2 and 3 make less plausible an alternative interpretation of the effects of separate element presentation in terms of reduction of the novelty of the element. The findings may be taken as implying that the elements of a simultaneously presented compound are joined by a single symmetrical association which acts at various points during a sensory preconditioning experiment.     

Electromyographic indications of laryngeal-area activity during stuttering expectancy

Using surface electrodes, mean microvolt values of laryngeal-area muscle activity were determined for 13 male and 6 female stutterers during 10-sec periods in which single words were silently read and stuttering expectancy was indicated. No significant differences in levels of laryngeal-area muscle activity were found between periods of fluency expectancy and stuttering expectancy preceding both fluent and stuttered speech. The results were interpreted as being nonsupportive of the hypothesis that a breakdown in stutterers' laryngeal-area muscle activity occurs during moments of stuttering expectancy. In addition, the results suggest that the most common rationale for the utilization of laryngeal biofeedback procedures to enhance fluency should be questioned.     

The effects of individual differences in test anxiety and type of orienting task on levels of organization in free recall

In Experiment 1, high and low test-anxious subjects recalled a list composed of words that could be organized either by taxonomic categories or first letters. High-anxiety subjects showed less recall and conceptual clustering. There was no anxiety difference in alphabetic clustering, but low-anxiety subjects used alphabetic clusters to bridge transitions between conceptual categories more often than did high-anxiety subjects. An initial orienting task which required semantic processing reduced the recall deficit for high-anxiety subjects but not the clustering deficit. Low-anxiety subjects seemed minimally affected by a nonsemantic-orienting task. Experiment 2 used a list that could be organized by associates or rhymes. High-anxiety subjects recalled less and exhibited less clustering of both types. The nonsemantic-orienting task depressed performance for both anxiety levels, though the effect was somewhat greater for high-anxiety subjects. Overall, these results provide little evidence to support the hypothesis that high-anxiety subjects process differently only for semantic content, but methodological limitations preclude unequivocally rejecting that view.     

Communicative stress and stuttering frequency during normal,whispered, and articulation-without-phonation speech modes

The effect of communicative stress on the frequency of stuttered syllables in 12 adult stutterers reading six different but equivalent passages using normal voicing, whispering, and articulation-without-phonation speech under a stress and a non-stress condition was studied. Although the frequency of stuttering was significantly greater in the normal voicing mode than in the whispering mode and greater in the whispering mode than in the articulation-without-phonation mode, no differences were found between the stress and the nonstress conditions with respect to stuttering.     

Neuropsychological significance of phonetically accurate and phonetically inaccurate spelling errors in younger and older retarded spellers

The performances of two groups of retarded spellers (who were equated with respect to the level of deficient performance in spelling, but who differed in the level of phonetic accuracy of their misspellings) at two different age levels were compared to those of normal spellers who had been matched for age and WISC Performance IQ with the retarded spelling groups. The results indicated very marked differences in a number of linguistic skills between the normal spellers and the retarded spellers whose misspellings were characterized by phonetic inaccuracy. The performances of the retarded spellers who produced a preponderance of phonetically accurate misspellings differed markedly from those of the normal spellers only when the task demands involved fairly complex linguistic-cognitive operations. For the most part, the differences among the three groups were in evidence only at the older age level studied.