Partial reinforcement effects and type of reward

In two experiments 68 rats were trained to bar press or run down a straight runway for food or for water under conditions of either continuous reinforcement or partial reinforcement. In both experiments, there was greater persistence of behavior which had been reinforced with food than with water. In Expt 2, the partial reinforcement extinction effect (PREE) was observed with food reward, but not with water.Within the context of the experimental procedures used, it can be concluded that the rat has mechanisms for developing persistence which are dependent on the specific motivational system involved. This conclusion is related to theories of partial reinforcement effects and to possible biological origins of the mechanisms.     

Avoidance conditioning as a function of appetitive stimulus pretraining: Response and stimulus transfer effects

Pretrained appetitive discriminative stimuli were used as warning signals in subsequent avoidance learning. In Expt 1 identical responses were required in pretraining and in avoidance learning. An appetitive S+ facilitated avoidance learning in rats in comparison to S? or a stimulus previously uncorrelated with food. In Expt 2, the type of response in pretraining and in avoidance learning was varied. Groups with homogeneous responses in the two situations replicated Expt 1 results, whereas groups with different responses in pretraining and avoidance learning failed to show an advantage when S+ served as warning; in the heterogeneous response groups, S? was as effective as S+. Inhibitory factors in the heterogeneous groups were discussed as an explanation for these results.     

Hobbits and orcs: Acquisition of a sequential concept

Subjects solved the hobbits-orcs problem repeatedly until they made no errors on two successive solutions. Groups varied in the kind of feedback given after errors. Further support was obtained for Thomas' (this journal) conclusion that subjects organize the sequence of moves in small subsequences, rather than individual moves. Differences between feedback groups suggested that the organization is oriented forward in the problem, and this contrasts with GPS' retroactive organization of this problem. Comparison between feedback groups also leads to the conclusion that subjects learned from positive information indicating which response is correct, rather than by a process of eliminating errors or sampling new strategies after errors. Analysis of acquisition data agreed with the hypothesis of all-or-none learning at individual states, except for one state where the additional complexity was related to an ambiguity about backward moves. The general pattern of results was invariant over a change in the characters of the problem (men and elves) designed to produce a reversal of relationship between the characters concerning who was prevented from outnumbering whom.     

Performance of expert abacus operators

Ten expert abacus operators were given various restrictions and distractions during addition of ten numbers of 3–5 figures. All subjects except one could calculate very rapidly without an abacus, probably relying upon its mental representation. Some of those at an intermediate level of mastery moved their fingers as if they had been manipulating a real abacus, and prohibition of this movement or interfering finger-tapping reduced their performance. All the subjects could answer simple non-mathematical questions during abacus calculation without increasing time or errors, but answering extraneous mathematical questions was very hard.     

The effect of an intensive behavioral program on the distribution of EEG alpha power in stutterers during the processing of verbal and visuospatial information

Prior to an intensive behavioral treatment program, stutterers showed greater than normal activation of the posterior frontal region of the right hemisphere during the performance of speech tasks. After treatment they showed increases in proportional alpha for most regions of the two cerebral hemispheres, but most markedly for the posterior frontal region of the right hemisphere for both verbal and nonverbal tasks. This increase resulted in a reversal of the previous R/L interhemispheric alpha relationships with the left posterior frontal region showing greater activation during speech after treatment. The relationship of this finding to previous findings is briefly discussed and an hypothesis of decreased inhibitory control of the right hemisphere at the posterior frontal region by the left hemisphere during speech in stutterers is proposed and briefly expounded.     

Measures of timed performance and intelligence

The question of an association between IQ and measures of timed performance derived from inspection time and reaction time was examined in a sample of 182 adults and by reanalyzing data involving 48 adults from a previously published study. Multiple regression analysis found that measures of timed performance accounted for as much as 25% of IQ variance in the normal population, but that the inclusion of borderline and mildly retarded subjects resulted in much higher correlation coefficients because of the markedly less efficient performance of these persons in tasks of this kind. This outcome raised doubts about the validity of combining data from retarded and nonretarded subjects. Results ran counter to claims that tasks of the kind used are largely uninfluenced by cognitive variables, so that findings are not necessarily explained satisfactorily in terms of a mental speed factor. It was concluded that these measures of timed performance do not, at this time, provide a basis from which a reliable culture-fair measure of intelligence might be devised.     

Exploring and reexploring issues of integrality,perceptual sensitivity,and dimensional salience

Some observations that can be described conveniently by investigators in terms of dimensional sensitivity and dimensional salience actually need not implicate the psychological reality of the dimensions for the subjects. The developmental hypothesis that stimuli are perceived often as integral in early childhood can account for such phenomena only with the assumption that young children often apprehend objects as global wholes, related to one another by overall similarity. Classification data, recently presented by J. R. Aschkenasy and R. D. Odom (Journal of Experimental Child Psychology, 1982, 34, 435–448) can be reinterpreted in this way. On this reinterpretation, Aschkenasy and Odom's findings are exactly what the developmental form of the integrality-separability hypothesis predicts. Moreover, a variety of other findings and lines of inference converge on the conclusion that, in young children, the use of overall similarity relations to organize perception and cognition predominates over the use of dimensional relations (and that the relative balance between these stimulus relations changes in development). Examples are selected from the literature on the natural development of word meanings, as well as from the literatures on children's and adults' classification.     

A category theory approach to cognitive development

The category theory concept of a commutative diagram is used to construct a model of the way in which symbolic processes are applied to problem solving. The model provides for a relationship between symbolic processes and the problem which depends on structural isomorphism and consistency, but is independent of similarity between symbol elements and problem elements. It is then shown that several different levels of thought can be distinguished within the basic model. More information is needed to assign symbolic processes to a problem in a consistent way with higher-level thought processes than with lower-level processes. These information-processing requirements permit the approximate age of mastery of each level to be predicted, thereby offering an alternate theory of cognitive developmental stages. Two experiments designed to test the theory are reported.     

The validity of form F of the Matching Familiar Figures Test with kindergarten children

Egeland and Weinberg's contention that form F of the Matching Familiar Figures Test is inappropriate for kindergarten children was examined. White, middle-class, suburban kindergarten children were given form F of the Matching Familiar Figures Test, as well as a series of tests varying in degree of response uncertainty. It was hypothesized that tasks identified as high in response uncertainty would be the best predictors of norm-referenced composite reflection-impulsivity scores. Stepwise multiple regression analysis supported this hypothesis. The results were interpreted as supporting the construct validity of the Matching Familiar Figures Test as an index of reflection-impulsivity among kindergarten children.     

A developmental study of the role of word order in comprehending Hebrew

Monolingual Hebrew-speaking subjects, 3, 4, 5, 6, 7, and 11 years old, as well as adults, were asked to interpret utterances consisting of two nouns and a verb. Some utterances included only word order cues while others included direct object marker and subject-verb gender agreement cues. Even though Hebrew word order is relatively free, when subjects used word order as an interpretive cue they generally assigned sentence relations according to the dominant SVO order of modern Hebrew. This trend was less strong for the interpretations of NNV utterances than of NVN and VNN utterances. There was no evidence of a developmental sequence for word order strategies. In addition, there was no evidence that word order, for any age group, was necessarily a dominant cue for assigning sentence relations when other linguistic information was available.