Counterconditioning and exposure-only in the treatment of specific (conditioned suppression) and generalized fear in rats

In Experiment 1 the conditioned suppression technique was used to condition specific fear, suppression of operent lever pressing for food to a discrete CS. The efficacy of four treatment conditions on fear reduction was evaluated. Counterconditioning in which exposure to the CS was contiguously paired with food was significantly less effective than noncontiguous CS exposure and food. An exposure-only effect was indicated by the superiority of all three treatments involving CS exposure (the above two plus a typical conditioned suppression extinction procedure) to treatment consisting of food only. The reverse counterconditioning effect and the exposure effect are consistent with current views that emphasize the centrality of aversive stimulus exposure in fear reduction. Experiment 2 investigated elimination of generalized fear produced by unsignalled, inescapable shocks in the lever-pressing apparatus. Two treatments (counterconditioning and exposure-only) were equally effective and they were superior to no exposure control treatment. The results of the two experiments reinforce recent attempts toward a reevaluation of the role of anxiety-competing responses in elimination of fear.     

Retrieval processes in fifth graders and adults

This research was concerned with retrieval processes which underlie conceptual clustering. In a free recall task with categorized lists, fifth graders' and adults' retrieval was examined temporally by means of interword response times. List organization and retrieval cue factors were manipulated in order to assess the developmental relevance of an hypothesized three component retrieval model. The results indicated that both age groups used a qualitatively similar retrieval strategy, involving search for and decoding of higher-order memory units. Providing retrieval cues eliminated the category search component, but also increased the likelihood of exhaustive recall attempts under random presentation conditions. The results were discussed in terms of the inter-relationships between storage and retrieval strategies. Age-related differences in retrieval time were attributed to insufficient reorganization during input and failure to attempt to recall all of a category's members.     

Rats' lever-press durations as psychophysical judgments of time

Hungry rats received food following lever-press durations exceeding a minimum value, which ranged from 0 to 6.4 sec. When no intertrial intervals separated successive presses, modal press durations remained at very short values as the minimum value required for food was increased. This was particularly true immediately after a food presentation. When an 8-sec intertrial interval followed each lever release, modal press durations were always at or beyond the minimum value required for food, and outcome of the preceding press had no effect on press duration. Possible reasons for the effects of intertrial intervals included punishment of short presses, increased delay of reinforcement of short presses, and reduced density of reinforcement. In addition, functions relating discrete-trials lever-press duration to minimum duration required for food were found to be qualitatively and quantitatively similar to the power functions recently proposed by Catania (1970) for interresponse time and response latency. This similarity was taken as support for a general psychophysical law of temporal judgments.     

Economical point plotter interface for a PDP-12 computer

An economical point plotter interface is described for the PDP-12 computer.     

The relationship of vocational decidedness and satisfaction with dogmatism and self-esteem

The purpose of this study was to investigate the relationship of levels of vocational decidedness and the satisfaction or dissatisfaction of one's level of vocational decidedness with dogmatism and self-esteem. The results indicated that vocationally decided and undecided subjects represent uniquely different populations on measures of dogmatism and self-esteem.     

THE EFFECTS OF PROMPTING QUESTION-ASKING UPON ON-TASK BEHAVIOR AND READING COMPREHENSION1

This study investigated a teacher-implemented prompting procedure for training students to ask questions. Two special-class (EMR) students who asked no questions were selected as subjects. Baseline data were also collected on reading comprehension and on-task behavior, and these suggested decreasing levels of performance. The results indicated that prompting was effective for initiating question-asking. In addition, increased levels of reading comprehension and on-task behavior were observed.     

Ability evaluation through social comparison

Two experiments were conducted to clarify and extend social comparison theory for abilities. In the first experiment, the hypothesis was supported that people want information about their ability level more when they anticipate making a decision about an action based on the ability than when the decision has already been made. The evaluative need is thus primarily a predecision phenomenon. The second experiment showed that the preference for comparison with similar others predicted by social comparison theory is strongest when those others have had experience utilizing the ability in situations relevant to subjects' decisions.     

Human auditory-evoked response: Specific effects of signal strength and performance criterion

Computer-averaged auditory-evoked responses were recorded from the scalp of seven human Sa in order to study the effects of both low-signal levels and different performance criteria upon specific components of the waveform. Noise bursts of ?2, 0. +2. or +6 dB seDl8tion level (SL) were presented contingent upon the S’s correct bisection of a temporal interval as the degree of accuracy required from him was systematically varied. Analyses of variance indicated that a positive peak in the waveform at a latency of approximately 300 msec increased in amplitude as the stringency of the performance criterion increased but showed no change as signal strength varied. The negative peak at approximately 125 msec latency increased with increasing signal strength but remained constant as the stringency of the performance criterion was varied.     

The effects of preexposure to a learning apparatus

ICR mice were given exposure to a one-way shuttle apparatus until locomotor activity had been habituated. When compared with nonexposed animals, the exposed animals displayed superior shuttle avoidance learning. Animals exposed to both the apparatus and the CS did not differ from the nonexposed group. It was concluded that preexposure to the learning apparatus facilitated acquisition, while preexposure to the apparatus in the presence of the CS did not. The relationship between this effect and habituation was considered.