Air-puff-elicited startle: Habituation over trials and measurement of a hypothetical emotional response

In the first of two experiments, it was demonstrated that an air puff elicited a reliable startle reflex in rats which showed no habituation over 50 trials. In the second study an attempt was made to measure an emotional response by recording startle reactions to the air puff during presentation of a presumed fear-eliciting CS. It was concluded that the air-puff-elicited startle reflex can be employed as an indirect measure of a hypothetical emotional response.     

Effects of a conditioned reinforcer upon accuracy of match-to-sample behavior in pigeons

Three pigeons were trained to perform a two-key sequential match-to-sample task. During baseline conditions, food reinforcement was contingent upon the first match response to occur following 8-min periods, and orange illumination of both keys preceded the delivery of food by 0.5 sec. The baseline schedule of food reinforcement was in effect throughout the study. In some conditions, a 0.5-sec flash of orange keylight alone was presented contingent upon mismatch responses that followed variable time periods averaging 1 min. Rate of mismatch responses increased and accuracy of matching performances decreased as compared with baseline conditions. The ability of the 0.5-sec orange flash to reinforce mismatch responses was markedly reduced when it no longer immediately preceded the delivery of food.     

Some experiments with computer synthesized speech

The generation of satisfactory artificial speech involves a great variety of semantic, linguistic, and articulatory factors. Many of these complex elements are as yet unknown, and computers are used extensively for their investigation. An account of an on-line, interactive computer facility used for such research at Bell Laboratories is given. The use of this facility for exploring the duration and pitch correlates of stress in English sentences is described.     

Statistical methods for a general theory of all-or-none learning

Greeno and Steiner have shown that a three state Markov Chain with a single absorbing state is equivalent to many of the current formalizations of All-or-None learning theories. Distribution statistics and other summary statistics are derived from the general model. Expressions for the maximum likelihood estimators of its parameters and the sampling variances of the estimates are presented. Likelihood ratio tests for several different null hypotheses are derived. These tests permit one to evaluate the usual null hypotheses in terms of the parameters of a process model.This research was supported in part by a USPHS Predoctoral Research Fellowship, 1-F1-MH-31-289-01, by a grant from the Graduate School of the University of Texas, and by grant HD-02212-01 from the National Institute of Child Health and Human Development to Dr. John Theios.     

A technique for the construction of discrete dichotic stimulation material

Procedures are described for the generation, synchronization. and accurate spacing of discrete dichotic stimulation material. A suggested standard definition of interpair interval is proposed.     

Variables underlying the recognition of random shapes

Speed of sorting decks of 32 cards with two alternative stimuli was measured. The stimuli were pairs of dots with attributes of distance between dots, angle of orientation of the pair, and position of the pair to the right or left of center. The attributes varied in relative discriminability and were used in all possible pair- and triple-correlated (redundant) combinations. Results showed an increase in speed of sorting with either an increase in discriminability or an increase in number of redundant attributes. It is argued that the increased speed with addition of redundant attributes is due both to a selective serial processing of attributes (requiring attribute separability) and to an increased discriminability with combined attributes (requiring attribute integrality).     

Detection and scaling of statistical differences between visual textures

Stochastically textured patterns were used to investigate the sensitivity of Ss to differences in the statistical distributions of locally defined properties of element density and shape. The results of the study indicate that when the textures were most structured, in terms of their variance, Ss were most accurate at detecting dissimilarities between pairs of patterns. Ss also rated the similarity of the statistical distributions of elements of patterns differing in local properties. Multidimensional scaling analysis of the ratings showed two dimensions, representing monotonic orderings of the stimuli.     

On the validity of scalp recordings of the auditory evoked potential

Simultaneous recording from scalp and cortical electrodes in unanesthetized and unrestrained cats revealed essentially no differences between the superficial and deep recordings of the auditory evoked responses. Human recordings taken under two conditions of muscular contraction contained no major differences from 30 to 300 msec after stimulus onset.