Coherence and Truth: A Cognitive Model of Propositional Truth Attribution

The truth value assigned to a proposition is treated by philosophers, logicians, and most psychologists as an abstract construct, a theoretical object outside the cognitive system. Breaking away from this consensus, we propose to carry out a psychological investigation to analyse the objective, verifiable properties of representations categorized as true by human individuals. We shall reject the conception whereby attributing a truth value to a proposition is the result of the activation of knowledge about the truth of that proposition. We shall also exclude the conception of truth as the result of the establishment of a correspondence with the world. We propose that truth be understood as the result of a decision about the values taken on by the conditions for fulfilment of the act of referencing in a mental model. Our cognitive model of propositional truth attribution is built on the assumption that the truth value of a proposition is determined by the ability of that proposition to fit into the theory of the field to which it refers. This attribution is viewed as a two-stage cognitive activity. During the first stage, the features defining the coherence of the proposition in the activated mental model determine its plausibility value. This defines a generally inconsistent set of truth candidates. The second stage involves selecting the subset containing all propositions which, in context, will be considered true. Two selection criteria are used: maximum consistency and connectivity. The preliminary experimental results proved to be compatible with the proposed model.     

Rats respond for food in the presence of free food: How free is the “free” food?

An experiment conducted by A.J. Neuringer (Science, 1969,166, 399–401) in which he reported that rats maintained appreciable levels of bar pressing for earned food in the presence of freely available food was critically examined and replicated. Rats were trained to bar press, then housed in operant chambers and administered a 15-day preference test between free and earned food, followed successively by 10 days of free food only, a second 6-day preference test, and 7 days of earned food only. Throughout the experiment half of the animals were provided with tall free-food containers similar to those used by Neuringer; the other half were provided with short containers similar to those more commonly employed by other researchers. The former animals showed a consistent propensity to bar press for earned food across both preference tests, while the latter animals showed only an initial propensity to bar press which subsequently declined to very low levels. These results indicate that the maintenance of significant amounts of bar pressing by the rats in Neuringer's report was due to the relatively more effortful free-food source he employed. The utility of a neophobia-optimality model in explaining the present data is discussed.     

THE EFFECTS OF TARGETING IMPROVEMENTS IN URINE GLUCOSE ON METABOLIC CONTROL IN CHILDREN WITH INSULIN DEPENDENT DIABETES

A treatment program designed to increase the percentage of negative urine tests was implemented using a multiple-baseline across groups design in a sample of 19 families of children with insulin dependent diabetes. The treatment involved instructions in insulin adjustment, decrease in intake of simple sugars and saturated fats, and increase in exercise, along with teaching the parents to support improvements in children's self-regulatory behaviors using a point economy and praise. New proocedures designed to measure and reinforce adherence to the urine testing regimen were developed. Results showed significant increases in percentage of negative urines consistent with implementation of treatment across the three treatment groups, which were maintained over the follow-up period. Metabolic measures of control, including glycosylated hemoglobin and serum glucose did not show improvements even though the relationship between the percentage of negative urine tests and glycosylated hemoglobin was very high during treatment.     

One extreme or the other or perhaps the golden mean? Issues of spatial resolution in face processing

The findings of some of the key studies that have examined the contribution of different bands of spatial information, specified in terms of cycles per face, to face recognition, and identification are reviewed. Based on findings from studies of low-, high-, and band-pass filtering, it is concluded that neither low facial scales nor high facial scales are optimal. Instead, a center range of facial scales, approximately 8-16 cycles per face, appears to make the greatest contribution to the recognition process. A study of identification of band-pass filtered faces is reported that reinforces the view derived from the literature. This indicated that a band with a harmonic mean of 11.1 cycles per face provided the most efficient recognition, with speed and accuracy declining at lower and higher bands.     

Expectancies for social contingency in 2-month-olds

In a classic report, Murray and Trevarthen (Emotional regulation of interaction between two-month-olds and their mothers. In T. Field & N. Fox (Eds), Social perception in infants (pp. 101–125). Norwood, NJ: Ablex, 1985) suggested that 6- to 12-week-olds were sensitive to contingency in maternal stimulation because they became upset during the replay of their mothers’ behavior during an initial period of live interaction over closed circuit TV. However, a number of concerns were raised about the procedure and it was argued that infants may simply have become increasingly fussy over time. To clarify this very important issue, we adopted a three-condition design (live–replay–live) and modified Murray and Trevarthen’s procedure by inserting a seamless shift from the initially live interaction period to a replay period of good maternal behavior. This was followed by a seamless shift back to a subsequent live interaction. Two-month-old smiling and gaze decreased while frowning and mouth closures increased during the replay period relative to the initial live interaction period, replicating Murray and Trevarthen’s results. Fussiness over time did not account for these results because seven of the ten babies increased their positive behaviors and decreased negative behaviors during the second live interaction period, and there was a significant increase in their visual attention to their mothers, thus suggesting a renewed interest in the previously noncontingent partner.     

The knowledge-structure and inductivist strategies in causal attribution: A direct comparison

Two different strategies for making causal attributions are distinguished. The first is the classic inductivist approach, which uses covariation information to arrive at causal attributions. The second is the knowledge-structure approach, which uses information relevant to knowledge about plans and goals to explain behaviour. Two experiments are reported in which information activating both types of strategy is given. The results indicate that goal-relevant information activates expectancies that resist the presence of explicit covariation information. The results are interpreted as indicating that expectancies generated by knowledge-structures are therefore different to those activated by verbs, which do not resist the effect of explicit covariation information. It is concluded that knowledge-structures constitute an alternative strategy of causal attribution to the inductivist strategy, and the nature of the relationship between the two strategies is considered.     

Citation Analysis of Skinner's Verbal Behavior: 1984-2004

The present study undertook an updated citation analysis of Skinner's (1957)Verbal Behavior. All articles that cited Verbal Behavior between 1984 and 2004 were recorded and content analyzed into one of five categories; four empirical and one nonempirical. Of the empirical categories, studies that employed a verbal operant from Skinner's analysis were assigned to either basic, applied, or observational categories. Empirical studies that did not employ a verbal operant were categorized as other-empirical. The total number of citations remained stable across the review period and averaged just over 52 per year. Of these, 80% were from nonempirical articles, 13.7% were from other-empirical articles, 4% were from applied articles, 1.4% were from basic articles, and 0.9% were from observational articles. An "obliteration" analysis was also conducted to identify articles that employed Skinner's verbal operant terms but did not cite Verbal Behavior. This analysis identified 44 additional articles, suggesting that a degree of obliteration had occurred in the half century since the publication of Verbal Behavior. In particular, the analysis suggests that the verbal operant of manding has sufficient presence in the applied empirical literature to render citation of Verbal Behavior redundant. Overall, Verbal Behavior continues to make an important contribution to the psychological literature.     

Orthographic influences on phoneme deletion response times

The aim of this paper is to provide further evidence that orthography plays a central role in phonemic awareness, by demonstrating an orthographic congruency effect in phoneme deletion. In four initial phoneme deletion experiments, adult participants produced the correct response more slowly with orthographically mismatched stimulus-response pairs (e.g., worth-earth) than with matched pairs (e.g., wage-age). This orthographic effect occurred with or without specific instructions to ignore spelling and when stimuli were presented with or without the to-be-deleted sound. In a final experiment, participants made more errors on complex than simple onset items, but there was no interaction with orthographic mismatch. The repeated observation of this robust orthographic effect suggests that participants are at least aware of orthography during phonemic awareness tasks, and it supports the view that phonemic awareness is directly subserved by orthography.