Some empirical justification for a modest proposal regarding data acquisition via intermittent direct observation

Computer simulations of behavior and event records of a child's visual fixation on an adult person were generated and sampled using a modified time sampling procedure. The modified approach required making two independent scoring judgments per observation interval: if the behavior was initiated within the interval, the interval was scored; if the behavior was ongoing precisely at the end of the interval, the interval was again scored. The results showed that the within-interval and end-of-interval scores yielded, respectively, estimates of behavioral frequency and duration. The accuracy of the estimates was a function of the number of observations. Several field studies demonstrated high agreement among observers who employed the measurement system.     

Concomitant changes in classically conditioned heart rate and corneoretinal potential discrimination in the rabbit (Oryctolagus cuniculus)

Corneoretinal Potential (CRP) and heart rate changes were measured in a series of differential classical conditioning experiments in which the directionality of the heart rate response was related to (a) CRP acquisition, and (b) the certainty or uncertainty of the stimulus situation. The results suggested that heart rate decelerations were associated with stimuli that predict upcoming aversive events, while heart rate accelerations were associated with asymptotic CRP responding late in conditioning. These findings were interpreted in terms of (a) changes in general somatic activity, and (b) the cue properties associated with CSs which predict aversive events.     

Placement or placebo: Does additional information change special education placement decisions

The effect of relevant information on the decision to place pupils in special education services was investigated. Ten placement decision committees were given information on 12 referred pupils, half of which included social history information on the pupil and orthogonally half of which were recommended for special education services by an outside psychologist. Analysis of the committee's 120 decisions revealed no significant relationship either between the psychologist's recommendation and the committee's decisions or between the presence of social histories and the committee's decisions. The results are discussed in terms of information advocacy within the committees.     

The effect of shock intensity upon responding under a multiple-avoidance schedule

The effect of two shock intensities (1.00 and 2.00 mA) were studied in the acquisition, maintenance, and extinction of unsignalled avoidance by albino rats. Single and multiple avoidance schedules were employed, with shock intensity being the principal condition that differed between schedule components. The higher shock intensity was generally more effective in producing avoidance. Higher response rates and lower shock rates were observed under high-intensity shock when performance stabilized. When the multiple schedule was introduced, the six rats trained under a single shock intensity all showed poorer performance under the new shock intensity, whether it was higher or lower than the training intensity. Performance under the original shock intensity did not change substantially with the introduction of a different shock intensity in the other multiple schedule component. Performance under the new shock intensity showed gradual improvement with continued exposure to it. All of the rats showed persistent “warm-up”, receiving approximately 40% of the total session shocks in the first one-sixth of the session. The degree of warm-up was unrelated to avoidance shock intensity.     

Hippocampal lesions and pavlovian cardiovascular conditioning

New Zealand albino rabbits received either sham, cortical control, or hippocampal lesions and were subjected to differential Pavlovian conditioning in which tones of different frequencies served as conditional stimuli (CSs), and a brief paraorbital electric shock train served as the unconditional stimulus. Heart rate (HR), blood pressure (BP), and electromyographic (EMG) conditional responses (CRs) were recorded. Animals with cortical and hippocampal damage or animals with cortical damage alone revealed attenuated bradycardiac CRs, but HR CRs of the former two groups did not significantly differ. BP changes were minimal; reliable differences were not obtained between CS+ and CS?. However, these changes consisted of small but reliable depressor responses, which were not affected by either cortical or hippocampal lesions. Few EMG CRs were obtained. These data, combined with those of previous experiments, suggest that forebrain structures may modulate higher level processing of stimulus information, perhaps in terms of assessing the biological significance of such stimulation.