The development of linear syllogistic reasoning

Between 24 and 26 children in each of grades 3, 5, 7, 9, and 11 (with mean ages of 8.5, 10.2, 13.0, 15.0, and 16.6 years, respectively) were tested in their ability to solve linear syllogisms, problems such as “John is taller than Mary. Mary is taller than Pete. Who is tallest? John, Mary, Pete.” Response latencies and error rates decreased across grade levels and sessions. Component latencies also generally decreased with increasing age. Four alternative information-processing models were fit to the group latency data at each grade level. These models were (a) a spatial model, according to which people represent the terms of a linear syllogism in the form of a linear spatial array; (b) a linguistic model, according to which linear syllogisms are solved via inferences on functional relations represented by linguistic deep structures; (c) an algorithmic model, according to which people solve linear syllogisms by applying a series of simple, essentially mechanical steps, and (d) a mixed model, which combines selected features of the spatial and linguistic models, and adds new features of its own. The latency data supported the mixed model at each grade level, although in grade 9 the model was not the preferred one until the second session of testing.     

Within-compound associations in a variety of compound conditioning procedures

Three experiments used a flavor-aversion preparation to demonstrate the occurrence of within-compound associations in various conditioning procedures. In Experiment 1 rats first received two separate two-flavor compounds, each followed by a mild US. They then received one element from one compound paired with a strong US and one element from the other compound nonreinforced. A subsequent choice test of the other two flavors from the compounds revealed that the consumption of each test flavor reflected the conditioning history of the element with which it had been paired. Rats drank less of the flavor whose associate had been paired with the strong US than of the flavor whose associate had been nonreinforced. In Experiment 2 within-compound associations were observed using a similar design in a blocking procedure in which one element from each of the two compounds was conditioned previously. Experiment 3 identified within-compound associations in a procedure where reinforced single element presentations were intermixed with nonreinforced compound presentations, as in a conditioned inhibition paradigm. These results suggest that within-compound associations occur in several important conditioning procedures which use multiple CS presentations.     

Influence of item identification on the memory performance of mentally retarded and nonretarded adults

The role of item identification in the memory performance of mentally retarded and nonretarded adults was examined by varying the identification and memory parameters of a sequential same-different task. In Study 1, retarded subjects' identification ability was demonstrated to be less efficient than nonretarded subjects' ability. In Study 2, target duration and interstimulus interval were varied. Memory performance differed between groups, and the memory deficit for retarded subjects was demonstrated to be independent of their identification deficit. The target durations in Study 2 were relatively brief, and in Study 3, the target duration was increased to insure that all subjects could identify the target. Mentally retarded subjects were demonstrated to have a memory deficit. The results were discussed in terms of possible sources of the memory deficit.     

Recovery of the US representation over time during extinction

Four experiments used a conditioned suppression procedure in rats to explore changes in the US representation over time during the course of extinction. They employed two previously reported effects: reinstatement of responding to an extinguished CS by separate US presentation, and the erasure of that effect by interposed nonreinforcement of a second excitatory CS. These effects have been interpreted as enhancing and depressing the US representation, respectively. Experiment 1 found the erasing effect to decrease but still to remain substantial after over a 4-day period, suggesting a partial recovery with time of a deliberately depressed US representation. Experiment 2 implicated this change as a contributor to the phenomenon of spontaneous recovery by showing that recovery to be sensitive to erasure effects. Experiments 3 and 4 found evidence for an interaction between the state of the US representation and the amount of associative change which results from nonreinforcement of an excitatory CS. When the US representation was strong, either because of reinstatement or the passage of time, nonreinforcement of a CS was especially effective in producing associative change. When the US representation had been depressed by erasure, those nonreinforcements produced relatively less associative loss. Moreover, these effects upon associations were reasonably stable in the sense that they left asymptotic differences in the strength of associations after extinction. Together with previous findings, these results point to an important role for the US representation in the performance and learning which occurs during extinction.     

A microgenetic model of paragrammatisms produced by a schizophrenic speaker

A series of papers appearing in Brain and Language ask whether schizophrenic language irregularities can be understood in linguistic terms. This literature is reviewed and the contrary positions of different authors are highlighted. The clinical presentation of a schizophrenic male is described. In a single interview he produced a set of paragrammatical errors which are noteworthy insofar as they indicate sustained epochs of diminished expressivity. In this sense, they differ from schizophasic deviance, which is described by Lecours and Vanier-Clement (Brain and Language, 3, 516-565, 1976) as an enhanced expressivity cooccurring with intact language competence. They are also partially decodable, which distinguishes them from the schizophrenic segments discussed by Chaika. Analyses of the paragrammatisms indicate disruptions at three discrete representational levels. One involves the formation of abstract speaker intentions, while the second organizes syntagms into some serial form, and the third level takes content words belonging to a particular syntagm and positions them in a syntactic frame. A microgenic model of these representational planes is proposed that is based on the theoretical perspective of Brown, as well as Garrett's investigations of normal speech errors. The model is justified insofar as the paragrammatisms indicate "linguistic regressions" back to more "thought-like" linguistic representations. Moreover, a recapitulation of specific linguistic mappings is demonstrated to occur between processing levels. This microgenetic model represents an extension of previous work in aphasiology insofar as it targets combinatorial rather than selectional processes as primary planes of disruption.     

Components of syllogistic reasoning

The present research sought to understand the components of syllogistic reasoning used in a syllogistic evaluation task. In this task, subjects must indicate whether a conclusion such as “Some Yale professors are humbugs” is definitely true, or never true of a set of premises such as “Some humbugs study syllogistic reasoning; some Yale professors study syllogistic reasoning”. A modified form of componential analysis (Sternberg 1977, 1978) was used to decompose the syllogistic evaluation task with abstract content into encoding and encoding plus combination subtasks. The response-choice data from these subtasks were used to provide (a) direct tests of a proposed theory of syllogistic reasoning, and in particular, of its assumptions about sources of error in syllogistic reasoning; and (b) direct inferences regarding the representation of relations between the subject and predicate of the premises as encoded and combined. The results supported a proposed transitive-chain model of syllogistic reasoning.     

Second-order conditioning with diffuse auditory reinforcers in the pigeon

Pigeon subjects were used in five experiments investigating second-order conditioning with visual second-order and diffuse auditory first-order stimuli. Experiment 1 used a discriminative conditioning procedure to demonstrate reliable and substantial second-order conditioning with these stimuli. In Experiments 2 and 3, extinction of the auditory first-order stimulus after second-order conditioning had little effect upon responding to the second-order stimulus, when compared to a stimulus whose reinforcer was maintained. Experiment 4 compared directly the susceptibility of second-order responding to extinction of the first-order reinforcing stimulus as a function of the modality of that reinforcer. When a visual second-order stimulus was paired with a visual reinforcer, and the response to the latter was extinguished, then second-order responding was greatly reduced relative to control levels. In contrast, when that reinforcer was an auditory stimulus, second-order responding was not affected by the current value of the first-order stimulus after conditioning. Finally, in Experiment 5 the auditory stimulus was established as a reinforcer through discriminative-operant training. Following second-order conditioning, extinction of responding to this stimulus again had little impact upon responding to the second-order stimulus with which it had been paired. These results are discussed in terms of previous work on second-order conditioning with rat and pigeon subjects.     

Intervention and sleeper effects: A reply to Clarke and Clarke

The evolution of the concept of “sleeper effects” is traced from the work of C. I. Hovland, A. A. Lumsdaine, and F. D. Sheffield, Experiments on Mass Communication. Princeton, N.J.: Princeton Univ. Press, 1949, to the present time. The concept originally referred to the delayed emergence of attitude change in persuasibility research. It has also been used in developmental investigations, with attendant theoretical problems that have not been fully addressed. These problems are examined, with the recommendation that the social psychologist's sleeper effect should be modified to meet developmental needs and renamed “delayed treatment effects”. Such effects are highly relevant to recent findings from studies of early childhood intervention programs.