Stimulus control and delayed reinforcement

Pigeons were tested for generalization along the line-orientation dimension, after being trained on various two-component multiple schedules. The first component contained either a variable-interval 1-min schedule of immediate reinforcement or an extinction schedule and was associated with a plain white key (S1). The second component contained a variable-interval 1-min schedule of delayed reinforcement and was associated with a black line on a white background (S2). The major results showed that (a) decremental gradients were obtained around the stimulus associated with the delayed reinforcement component when S1 was associated with extinction, but that incremental gradients were obtained when S1 was associated with immediate reinforcement, (b) the subjects' pretraining did not affect the generalization gradients if sufficient training on the terminal multiple schedule was provided, and (c) changing the S1 schedule from immediate reinforcement to extinction produced behavioral contrast if reinforcement was delayed for 10 sec during S2, but not if it was delayed for 20 sec.     

An introduction to microcomputer networking concepts

This paper presents a brief history of the use of internal computer networks, an introduction to networking concepts and topology, and suggestions regarding a possible system for use in a psychology laboratory. Considerations about the design and use of a microcomputer network are discussed.     

Electrode placement,EMG feedback,and relaxation for tension headaches

Fifteen tension headache subjects were allocated to one of three groups: direct EMG feedback (from a site corresponding to the source of pain), indirect EMG feedback (from a site not corresponding to the source of the pain) and relaxation instructions. There were two base-line, six treatment and one post-treatment sessions. No significant differences were found between base-line and post-treatment EMG levels, for any of the groups; however, some significant reductions in levels were obtained within sessions. EMG levels recorded during headache attacks did not differ significantly from levels recorded during base-line. Frequency and intensity of headaches were significantly reduced, particularly in the relaxation group. At follow-up this improvement was maintained for subjects with forehead pain, but differences between the groups had disappeared.     

Primary versus secondary rehearsal in imagined voices: Differential effects on recognition

Subjects were asked to rehearse word trigrams in a particular prefamiliarized male or female voice for 5, 10, or 15 sec. In Experiment 1, recognition performance improved with the amount of primary (maintenance) rehearsal only if the speaker's voice at test matched the rehearsal voice, but recognition performance improved with the amount of secondary (elaborative) rehearsal regardless of the sex of the speaker at test. With a visual testing procedure in Experiments 2 and 3, the amount of primary rehearsal given to a trigram had no effect on recognition performance unless the original voice context was reinstated mentally at test. These results suggest that: (a) Secondary rehearsal builds up semantic associations, whereas primary rehearsal serves to associate items with their physical characteristics at presentation. (b) There is an important memory search component in recognition as well as in recall. (c) Imaginal operations can yield a product in memory that is similar to that left by perceptual operations.     

Contextual potentiation of acquired behavior after devaluing direct context-US associations

In two experiments, water-deprived rats were exposed to tone-footshock pairings in a particular conditioning context. In Experiment 1, the training parameters were selected on the basis of parametric pilot data so as not to produce direct associations between the conditioning context and footshock. Despite independent evidence of no appreciable direct association between the conditioning context and footshock, animals tested in the conditioning context exhibited more lick suppression to the tone than other animals tested with the tone outside of the conditioning context. Thus, the conditioning context potentiated suppression to the tone in the absence of appreciable fear of the conditioning context. In Experiment 2, training parameters were used that permitted the formation of direct associations between the conditioning context and footshock; however, for half the animals, these associations to the context were then extinguished. With the tone absent, a comparison of extinguished animals tested either in the conditioning context or outside the conditioning context detected no differences in suppression, demonstrating the effectiveness of the extinction manipulation. However, other animals also subjected to extinction of direct context-footshock associations displayed greater suppression to the tone within the conditioning context than comparable animals tested outside the context. Collectively the data indicate that the superior retention-test performance seen within the training context can arise both from the commonly assumed direct associations between the training context and the unconditioned stimulus and from the potentiation by the training context of the associations between the nominal conditioned stimulus and unconditioned stimulus.     

The Pittsburgh Initial Neuropsychological Testing System (PINTS): A neuropsychological screening battery for psychiatric patients

This paper presents a new neuropsychological screening battery for psychiatric patients. It takes 1.5 to 2 hr to administer and briefly assesses general level of performance, memory, language skills, attention, and spatial-constructional abilities. Scoring and profiling are computerized. Initial validation based on discriminant analysis of a group of brain-damaged and non-brain-damaged psychiatric patients yielded a diagnostic accuracy level of 84.51%. Cross-validation on a different population led to a substantial attrition of classificatory accuracy, but cross-validation based on a comparison between two samples drawn from a homogeneous population yielded substantially less attrition. It was concluded that while the battery discriminates accurately in a homogeneous population, it is necessary to develop separate norms for populations varying in level of impairment.     

Assessment of social anxiety: a controlled comparison among social phobics,obsessive-compulsives,agoraphobics, sexual disorders and simple phobies

The construct validity of the Willoughby Personality Schedule (WPS) as an index of social anxiety was established in the present study. The WPS correctly identifies social phobics from controls in 88% of the cases.