Memory and frequency estimation processes in a decision task

Two experiments examined the role of information storage and frequency estimation processes in a simple decision task. On each trial from one to five simultaneous sequences of information were presented, and subjects were required to monitor and respond to each sequence. In one study independent groups of subjects gave decisions, recognition responses. or frequency judgments. In a second study recall responses were obtained from subjects as part of the decision and frequency judgment tasks. Changes in performance as the number of simultaneous sequences increased suggested an independence of decisions from memory for specific information. Performance on the decision and frequency judgment tasks exceeded at times that which was possible on the basis of specific information available. Other data suggested that subjects in the frequency estimation tasks maintained an accurate frequency count when possible, but in the decision task kept little more than a record of their currently favored hypothesis. When direct counting was prevented in the second experiment. performance in the two tasks was not significantly different, suggesting that the two processes are very similar under such conditions.     

Manipulation of response-contingent unconditioned-stimulus intensity in human eyelid conditioning: A two-phase model analysis

Four groups of human subjects were given 360 classical eyeblink conditioning trials. All groups received the same UCS (unconditioned stimulus) intensity on[Formula: see text] (nonconditioned response) trials but differed in the intensity presented on CR trials. Response probability increased as a positive function of UCS intensity on CR trials. Phase 1 of the two-phase model was longer when no UCS was presented on CR trials, but did not differ in duration among the remaining three groups. Most subjects could be described with a single operator in Phase 2, the operator limit increasing as a positive function of CR-contingent UCS intensity. For subjects requiring different operator limits on CR and[Formula: see text] trials, the latter was lower with high CR-trial intensities but higher with low CR-trialintensities. The results were interpreted to be more consistent with drive theory than with "law-of-effect" or two-factor theories.     

Self-consciousness, self-awareness, and self-attribution

Self-awareness was either manipulated by a mirror (experimental) or not (control). Subjects were selected for being high or low in private self-consciousness (disposition to attend to one's thoughts, feelings, motives). Private self-consciousness had a stronger effect on self-attributions than did self-awareness. These findings have implications for attribution, self-consciousness, and the relationship between manipulations and dispositions.     

Auditory evoked potentials during selective listening to dichotic speech messages

The sensitivity of the scalp-recorded, auditory evoked potential to selective attention was examined while subjects monitored one of two dichotically presented speech passages for content. Evoked potentials were elicited to irrelevant probe stimuli (vowel sounds) embedded in both the right- and the leftear’s message. The amplitude of the evoked potential was larger to probe stimuli embedded in the attended message than to probe stimuli in the unattended message. Recall performance was unaffected by the presence of the probes. The results are interpreted as supporting the hypothesis that this evoked potential sensitivity reflects an initial “input selection” stage of attention.     

Detection errors on the word the: evidence for reading units larger than letters.

In four experiments, subjects read 100-word passages and circled instances of the letter t. Subjects missed a disproportionate number of ts in the word the. Evidence was provided against explanations of this effect involving the location and pronunciation of the t in the and against an explanation in terms of the redundancy of the. Rather the high frequency of the appeared to be critical, and it was suggested that high-frequency words are read in terms of units larger than the letter.     

Electromagnetic articulography: use of alternating magnetic fields for tracking movements of multiple points inside and outside the vocal tract

The purpose of this paper is to present a new electromagnetic device which uses alternating magnetic fields for tracking movements of multiple points inside and outside the vocal tract. It is biologically safe, noninvasive, it does not interfere with speech movements, allows for multiple recording in the same subject, and for easy collection of large amounts of data. It is especially suitable for evaluation of patients with speech motor impairments.