Incidental learning,attention, and curiosity in squirrel monkeys calorie deprived as infants

The long-term effects of infantile malnutrition on information processing were studied in squirrel monkeys. From 2 through 8 weeks of age, four low-calorie infants were fed reduced amounts of a high protein diet, limiting their mean body weight gain to 23% of that of four well-fed controls, with all of this gain occurring during the first 2 weeks on the low-calorie diet. Thereafter, both groups received the standard diet ad libitum. At 68 weeks of age, incidental learning was tested by introducing shape cues that were redundant to the solution of a previously learned, two-choice, color discrimination. Removal of the color cues showed that the low-calorie monkeys had learned significantly less about the shape cues than had the controls. The basis for this incidental learning failure was then examined with an embedded-figures dicrimination, to measure attentional ability, and a novel stimulus substitution task, to measure curiosity. The groups did not differ in detecting embedded figures, but the low-calorie monkeys were significantly less likely than controls to select or handle novel stimuli that had been substituted for previously learned discriminative cues. It was concluded that undernutrition in infancy may induce a long-term strategy of only learning information which leads to an immediate reward, while suppressing the acquisition of information due to intrinsic curiosity.     

Psychology and "ordinary language"—a critique of Smedslund

This article takes up methodological issues of the kind raised by Jan Smedslund in earlier issues of this journal, concerning the status of psychological enquiry as a discipline. Arguments are presented which aim to show that Smedslund has failed to establish the thesis that all generally valid theoretical statements in psychology are explications of conceptual relationships embedded in ordinary language, i.e., analytic statements. Some specific examples of what Smedslund takes to be "ordinary language theorems" are examined. Doubts are expressed concerning the validity of the proof procedure Smedslund employs in the "demonstration" of a number of his alleged theorems. Finally, it is argued that the results produced by the situation-bound and culture-bound empirical research of the psychologist need not be viewed as "arbitrary" in Smedslund's sense of that term.     

Finite axiomatization for some intermediate logics

LetN. be the set of all natural numbers (except zero), and letD _n ^* = {k ∈N ∶k|n} ∪ {0} wherek¦n if and only ifn=k.x f or somex∈N. Then, an ordered setD _n ^* = 〈D _n ^* , ? _n , wherex? _ny iffx¦y for anyx, y∈D _n ^* , can easily be seen to be a pseudo-boolean algebra. In [5], V.A. Jankov has proved that the class of algebras {D _n ^* ∶n∈B}, whereB =,{k ∈N∶ ? \(\mathop \exists \limits_{n \in N} \) (n > 1 ≧n ² k)is finitely axiomatizable. The present paper aims at showing that the class of all algebras {D _n ^* ∶n∈B} is also finitely axiomatizable. First, we prove that an intermediate logic defined as follows: $$LD = Cn(INT \cup \{ p_3 \vee [p_3 \to (p_1 \to p_2 ) \vee (p_2 \to p_1 )]\} )$$ finitely approximatizable. Then, defining, after Kripke, a model as a non-empty ordered setH = 〈K, ?〉, and making use of the set of formulas true in this model, we show that any finite strongly compact pseudo-boolean algebra ? is identical with. the set of formulas true in the Kripke modelH _B = 〈P(?), ?〉 (whereP(?) stands for the family of all prime filters in the algebra ?). Furthermore, the concept of a structure of divisors is defined, and the structure is shown to beH D _n ^* = 〈P (D _n ^* ), ?〉for anyn∈N. Finally, it is proved that for any strongly compact pseudo-boolean algebraU satisfying the axiomp ₃∨ [p ₃→(p₁→p₂)∨(p₂→p₁)] there is a structure of divisorsD _* ⁿ such that it is possible to define a strong homomorphism froomiH D _n ^* ontoH D _U . Exploiting, among others, this property, it turns out to be relatively easy to show that \(LD = \mathop \cap \limits_{n \in N} E(\mathfrak{D}_n^* )\) .     

An information processing system for the psychiatric emergency room

An information processing system for a psychiatric emergency room is described. Several studies are presented that show the utility of the system. In the first study, variables involved in diagnosis are explicated. The second study attempts to determine the characteristics that distinguish recidivists from nonrecidivists at an emergency room. The third study attempts to find patient variables related to success in short-term treatment programs. The final study is aimed at discovering whether there are psychopathological effects related to the use of inhalants. Together, these studies show the potential of a mental health information system for learning more about the nature of mental disorders and their treatment.     

Alternative solutions to kinetic stimulus transformations

It has been assumed that certain stimulus transformations lead directly to depth effects, that is, that such transformations are the necessary and sufficient conditions for kinetically generated depth perception. An alternative is to view such perception as the preferred solution to the problem posed by the transforming stimulus as to what even in the world is producing that transformation. In several experiments it is shown that when other solutions are supportable by the stimulus, those same transformations will no longer lead to depth perception. These other solutions become preferred on the basis of rejection of certain coincidental features of the stimulus that otherwise would have to be accepted were the kinetic depth solution to be maintained. The findings are interpreted as challenging any theory that perception is simply the direct result of stimulation or of extraction of stimulus information and as supporting the Helmkoltzian rule of perception as a construction of the most reasonable representation.     

Does nutrition cause intelligence? A reanalysis of the Cali experiment

Recent literature has suggested there is a causal link between malnutrition and impaired cognitive development. From a selective review of this literature it is concluded that owing to methodological imperfections in many of these studies the presence or absence of such a link cannot be established, even if randomized experiments were to be carried out. It is argued that compensatory experiments, even though they are not as logically compelling as experiments where proper nutrition is withheld, are ethically justifiable and more useful strategically since they may suggest ways of improving the cognitive development of currently affected children, especially if a variety of compensatory treatments is implemented. A reanalysis of such an experiment was conducted to determine whether the nutritional or educational component of the treatment was responsible for the observed gains in cognitive development. The reanalysis indicated that after four years of treatment there was no association between cognitive and nutritional status. The results were discussed in relation to previous research. Some of the social implications of the results were also discussed.     

Televised classroom events as distractors for reading-disabled children

Three experiments examined the influence of videotaped classroom events on the academic performance and study behavior of reading-disabled and normally reading children in grades 1 through 6. In experiments 1 and 2a an experimenter-controlled presentation of these distractors resulted in performance decrements, the magnitude of which was greater for higher difficulty tasks. The distractor effects were similar for the two groups in this condition. However, when the children themselves were allowed to control their degree of exposure to the same distractors in experiment 2b, the reading-disabled children were less likely to act to escape the distraction. Results are discussed in terms of children's metacognitive awareness of distraction, and implications for the classroom are considered.     

How to maximize reward rate on two variable-interval paradigms

Without assuming any constraints on behavior, we derive the policy that maximizes overall reward rate on two variable-interval paradigms. The first paradigm is concurrent variable time-variable time with changeover delay. It is shown that for nearly all parameter values, a switch to the schedule with the longer interval should be followed immediately by a switch back to the schedule with the shorter interval. The matching law does not hold at the optimum and does not uniquely specify the obtained reward rate. The second paradigm is discrete trial concurrent variable interval-variable interval. For given schedule parameters, the optimal policy involves a cycle of a fixed number of choices of the schedule with the shorter interval followed by one choice of the schedule with the longer interval. Molecular maximization sometimes results in optimal behavior.