Adaptation is automatic

Two experiments were used to test whether selective adaptation for speech occurs automatically or instead requires attentional resources. A control condition demonstrated the usual large identification shifts caused by repeatedly presenting an adapting sound (/wa/, with listeners identifying members of a /ba/-/wa/ test series). Two types of distractor tasks were used: (1) Subjects did a rapid series of arithmetic problems during the adaptation periods (Experiments 1 and 2), or (2) they made a series of rhyming judgments, requiring phonetic coding (Experiment 2). A control experiment (Experiment 3) demonstrated that these tasks normally impose a heavy attentional cost on phonetic processing. Despite this, for both experimental conditions, the observed adaptation effect was just as large as in the control condition. This result indicates that adaptation is automatic, operating at an early, preattentive level. The implications of these results for current models of speech perception are discussed.     

Demonizing and mental illness (2) the problem of assessment: Los Angeles

Pastoral Psychology -     

Odor as a conditioned inhibitor: Applicability of the Rescorla-Wagner model to feeding behavior

Hooded rats were given conditioned inhibition training in which the taste of saccharin alone was always followed by induced illness, but the taste of saccharin plus the odor of amyl acetate was not. In a series of three subsequent tests—summation, enhancement of conditioning, and retardation—it was demonstrated that the odor had acquired active inhibitory properties. The results paralleled those obtained with more traditionally studied stimuli and techniques and hence were found to be readily predictable from a recent model of conditioning set forth by Rescorla and Wagner (1972).     

Memory for general and specific sentences

Cued recall indicated that memory was better for sentences containing specific verbs (e.g., scratched) than for sentences containing general verbs (e.g., injured). When synonymic verb responses were included, however, the general-specific difference was eliminated. Also, for complete sentence recall, subject nouns were better retrieval cues than verbs or object nouns. nt]mis|This research was supported by National Science Foundation Research Grant GB-22664 to L. Starling Reid and by a grant to the author from the Denison University Faculty Development Activities Program. Thanks are due Bill Stehle and Larry Giordano, who assisted in data collection and analysis.     

Psychophysical study of numbers

Summary This paper develops three theoretical models to predict the numbers generated by Ss in an experiment described by Baird and Noma, 1975, Exp. II. The models (digit, base, and quarter) are each grounded on different assumptions about the process underlying number generation without the constraints of physical stimuli usually present in psychophysical tasks. Each of the models proved applicable to a restricted subrange of the physical continuum from 1–1000. A combination of models seems necessary to adequately predict number generation.This article is the second in a five-part series. Reprint requests should be sent to John C. Baird.     

Classical conditioning of the nictitating membrane response of the lemon shark (Negaprion brevirostris)

An experimental group of lemon sharks received 100 daily presentations of light flash as the conditioned stimulus (CS) and electric shock as the unconditioned stimulus (US) in a classical conditioning situation. The conditioned responses (CRs) and unconditioned responses (URs) under observation consisted of extensions of the nictitating membrane. Separate control groups received either (a) no CS or US, (b) CS-alone, or (c) completely random presentations of CS and US. Few CRs occurred in the experimental group at the outset of conditioning, but the percentage of CRs during the second half of the first acquisition session exceeded 95%. Conditioning stabilized above 95% CRs during Acquisition Sessions 3 through 7. These responses could not be attributed to pseudoconditioning, sensitization, or other nonassociative factors. When the experimental group was subsequently given six CS-alone sessions, the course of extinction was gradual. Most results seemed similar to those previously obtained during classical conditioning of the nictitating membrane in rabbits.     

A high-speed algorithm for computing conditional probabilities of substrings of sequentially observed data

An algorithm is described that computes relative frequencies of occurrence of all arbitrarily long substrings of sequential data, such as are obtained from experiments in learning/memory and verbal interaction. The algorithm offers high speed and provides systematization for the computation of empirical conditional probabilities. Use of this algorithm allows application of probabilistic and information theoretic disciplines to reveal dependencies between events separated arbitrarily in time.