Effects of increased processing load on parallel processing of visual displays

Display elements were sequentially painted upon a display scope in regular and irregular spatial-temporal orders. The primary result of Mayzner, Tresselt, and their associates is confirmed: within specified temporal-spatial limits, display elements may be perceptually blanked. Characteristics of perceptually blanked elements can, however, be revealed by forced-choice testing. The accuracy of tilt discrimination for perceptually blanked elements is equal to, or better than, that for nonblanked elements. Perceptually blanked elements can also be distinguished from absent and from partially absent elements, presumably on the basis of a crude brightness discrimination. Sequential blanking effects as revealed in the accuracy of slant detection, are not critically dependent upon the magnitude of uniform spacing between the display elements.     

Neuroendocrine and behavioral correlates of constitutional differences

Consistent and stable individual differences were observed in the renal responses of water-loaded dogs during the development of Pavlovian conditional motor defense reflexes by electrocutaneous reinforcement. Some dogs developed persistent and intense conditional antidiuretic responses (with a high urine osmolality) to the entire Pavlovian conditioning room complex, whereas other dogs failed to exhibit conditional antidiuresis. In contradistinction to the conditional motor defense reflexes, the conditional antidiuretic responses showed poor differentiation, thus demonstrating the phenomenon of schizokinesis discovered by Gantt. In addition to conditional water retention, the antidiuretic dogs also exhibited persistent hyperpnea, copious salivation and tachycardia. The physiologic responses of the antidiuretic dogs to the Pavlovian conditioning room resemble those described by Walter B. Cannon for a “fight or flight” response,i.e., physiologic reactions of animals engaged in intense muscular effort. The antidiuresis serves the function of conserving body water so that it may be available for evaporative cooling in order to maintain thermal homeostasis. Since our experimental dogs cannot engage in a consummatory “fight or flight” response, their physiologic reaction to a stressful psychologic environment can be considered maladaptive. Pharmacologic analysis suggested that the antidiuretic responses may involve cholinergic transmitters.     

Mouse aggression and the intruder-familiarity effect: evidence for multiple-factor determination c57bl

Male house mice attack their familiar cagemates less than novel intruders-an effect often attributed to habituation of aggression toward odors emanating from the cagemate. This interpretation is overly simplistic in that the effects of familiarizing preexposure depend additionally upon two factors. One factor is the aggression-inhibiting odors emanating from the test male that are deposited onto the cagemate by cohabitation. Supporting evidence is that attack inhibition to the cagemate failed to generalize to noncohabiting same-strain intruders and that eliminating physical contact between subject and cagemate during preexposure prevented the usual postexposure decline in aggression. The second factor is nonolfactory social stimuli emanating from the cagemate during aggressive encounters. The same intruder odors that elicited aggression when placed on a socially active mouse elicited only investigation when placed on models. When subjects were preexposed to an intruder's odor while prevented from socially interacting with the intruder, this investigation subsequently declined while aggression paradoxically increased.     

The use of olfactory cues in solving a visual discrimination task

Albino rats, trained in a miniaturized WGTA, were found to learn an olfactory discrimination despite the fact that visual cues were relevant and obvious. The results provide a further warning against the use of macrosmatic animals in visual discrimination tasks in which olfactory cues may be relevant.     

The roles of contour and luminance distribution in determining perceived centers within shapes

Two sources of visual information that likely could be employed by the perceptual system in locating the centers of bounded shapes—boundary configuration and luminance distribution—have been perfectly confounded in every study thus far aimed at investigating perceived centters. Observers, using either a revolving or stationary x-y plotter, made judgments on the location of centers within either revolving or stationary shapes of both uniform and varied luminance distributions. Results indicate that the location of perceived centers depended predominantly upon boundary contour and was affected by the distribution of luminance within these edges to a much lesser degree.     

Cortical evoked responses to synonyms and antonyms

The brain’s processing of synonymity and antonymy was explored by examining the cortical evoked responses to correct judgments that a test word was a synonym or an antonym of a standard word presented 1 sec previously. Each of five subjects judged 256 pairs of words in each of two sessions. The evoked response to the second word was averaged separately for synonym and antonym pairs. Presentation of each test word as a synonym or an antonym, the order of presentation of each pair, and the side of the “synonym” response key were counter-balanced within subjects. The difference between the averaged response to antonym test words and that to synonym test words differed biphasically over the interval 250-650 msec after the stimulus. The demonstration of an evoked response difference between synonyms and antnyms extends the applicability of evoked potentials from attributes of individual word meaning to the semantic relationships between words.     

Dependent processing in dichotic listening as a function of word meaning attributes

Single dichotic word pairs were presented for immediate identification. Recognition probability was greater and response latencies shorter for high- than for low-frequency words. Both recognition measures were also affected by the frequency of the word accompanying the target word, performance being facilitated by a high-frequency partner and sometimes impaired by a low-frequency partner. Associative meaningfulness had similar, though less reliable, effects whereas the effects of word concreteness-abstractness were inconsistent. Recognition accuracy was generally superior for right-ear inputs, but recognition latency did not show consistent ear effects. Similar results were obtained under both unrestricted (Experiment 1) and controlled (Experiment 2) ear order of report instructions. The findings are consistent with a limited capacity interpretation of secondary processing in word perception.     

Teacher resistance to computer-assisted instruction

The need to introduce computers to a greater extent in teaching technology is discussed. Further, the potential importance of affective responses in the teacher’s acceptance of the computers is developed. A semantic differential scale was employed to measure preservice teachers’ attitudes toward the computer, computer-aided instruction, science, mathematics, and the teaching of science and mathematics. Considerable negative affect was found toward computers, computer-aided instruction, and teaching of science and mathematics. Implications for the ways in which computer-aided instruction is introduced are discussed.     

The MicroAce: An inexpensive computer controller

A $200 computer system is described that can act as a laboratory controller. Advantages and disadvantages of the system are discussed.     

A nonobtrusive heart rate telemetry system for rats

A harness for recording heart rate (HR) from unrestrained rats and an inexpensive FM transmitter for broadcasting high-resolution EKGs are described. The harness, which employs surface electrodes rather than skin pins or implanted electrodes, is especially valuable for recording HR over extended periods of time. Because it is comparatively free of noise generated by the animal’s activity, the system is applicable to a wide range of experimental conditions. Sample HRs obtained from three strains of rats while engaging in different behavioral categories are presented.