Sporadic transient atrioventricular block and slow heart rate in nervous pointer dogs

Two behaviorally distinct strains of pointer dogs, one bred for nervousness (pronounced freezing behavior, withdrawal behavior), the other bred for normal behavior, exhibit prominent differences in their heart rates and incidence of sporadic occurrences of atrioventricular heart block. Of 67 nervous-line dogs, 70 per cent showed second degree AV-block on at least one occasion, and their heart rates averaged 65 beats/min. Only 15 per cent of 52 normal-line dogs displayed AV-block (generally fewer instances per dog) and their heart rates averaged 110 beats/min. Fifth generation nervous-line puppies, two to six weeks old, exhibited occasional AV-block even at heart rates averaging 183 beats/min. The incidence and “severity” increased as the puppies aged. Dogs crossbred from second and third generation parents of the two main lines show intermediate incidences of AV-block and intermediate heart rates. The incidence of AV-block is predominant in females. This is interpreted as a sex-influenced, agedependent, polygenic mode of inheritance. Humoral factors probably account for the sex-influence, and psychological stress probably also plays a role. No sex difference is noted in heart rates.     

Development of an inexpensive remote radio control system for slide projection

An inexpensive remote radio control system for slide projection has been developed. It consists of an electronic receiver/decoder designed for attachment to commercially available slide projectors and a self-contained, portable FM transmitter with a foldable (collapsible) antenna/pointer. The system allows remote lens focusing (forward and backward) and slide change (forward and reverse) to be accomplished over a 100-ft range. It offers desirable freedom of movement to the lecturer or behavioral researcher, by eliminating locational restraints imposed by the extension cord.     

Procedure for operant conditioning of the dog

Most reports arising from operant conditioning procedures have little or no emphasis on the actual behavior shaping or acquisition phase of the responses which are the cumulative frequency of the well-practiced act. There is a need for more detail for beginners or those desiring a clearer understanding of procedures leading to the finally reported data. The procedure reported here is typically used to compare animal subjects or conditions, such as drugs, both in the acquisition and final phases of behavior. Beginning with an unconditional response (e.g. feeding) a bridging stimulus is paired in classical conditioning fashion. From that point on the bridging stimulus and UCS (feeding—or shock) are used immediately as reward or reinforcement only for responses “in the direction of the final desired behavior. The number of timed standardized behavior shaping sessions to criterion is the best index of acquisition phase performance and the total number bar presses or the rate of bar pressing (slope) is the usual index of operant responding. With timid animals it is often necessary to administer tranquilizers.     

Psychopharmacologic facilitation of operant conditioning of genetically nervous catahoula and Pointer dogs

Previous work has demonstrated that a genetic factor underlies much of the disturbed behavior in one strain of short haired pointer bird dogs (E line) maintained for several years in our laboratory. In some dogs the behavior is seemingly permanent and is characterized by human avoidance, excessive startle, reduced exploratory activity, and “freezing” or catatonic posturing. Another strain of dogs, catahoulas, with a high incidence of disturbed behavior similar to that above but with much less catatonic posturing, was made available for study also. In both of these strains defensive reaction and gross avoidance behavior often prevents the acquisition and later performance of operant conditioning (bar pressing for food reward) unless supportive tranquilizing chemotherapy is given. The chief interest in this study is, (1) the nearly permanent disharmony in the animal which seems to be an example of Gantt’s concept of schizokinesis, and (2) a comparison of 12 psychoactive compounds widely used in psychiatry for their effectiveness in restoring integrated adaptive functioning even in the most disturbed of the animals in our colony. The results show that: 1. even dogs with the most severe schizokinetic disabilities of many years duration have learned the operant conditioning (bar pressing); 2. however, it was and has remained necessary to facilitate both behavior shaping and nearly all later performances throughout the following year with benzodiazepine tranquilizers and these were far superior to any of the several other drugs tested; 3. neither gradual or rapid withdrawal nor sudden stopping of benzodiazepines allowed the dogs to continue the bar pressing. In fact, during withdrawal of the drug, performance seemed to parallel blood levels as reported in the literature.     

Natural theology: Theism or antitheism?

I propose that reasons advanced in support of theism serve just as well, or can be modified to serve just as well, as reasons for believing that there exists a wholly evil supreme being (‘antitheism’). Accordingly, I suggest that attempts to justify theism are futile, since all would-be success is neutralized by the corresponding support that is thereby provided for antitheism.     

Author Index Volume 111 2002

Philosophical Studies -     

Morphological changes in dendritic spines of Purkinje cells associated with motor learning

Experience-dependent changes of spine structure and number may contribute to long-term memory storage. Although several studies demonstrated structural spine plasticity following associative learning, there is limited evidence associating motor learning with alteration of spine morphology. Here, we investigated this issue in the cerebellar Purkinje cells using high voltage electron microscopy (HVEM). Adult rats were trained in an obstacle course, demanding significant motor coordination to complete. Control animals either traversed an obstacle-free runway or remained sedentary. Quantitative analysis of spine morphology showed that the density and length of dendritic spines along the distal dendrites of Purkinje cells were significantly increased in the rats that learned complex motor skills compared to active or inactive controls. Classification of spines into shape categories indicated that the increased spine density and length after motor learning was mainly attributable to an increase in thin spines. These findings suggest that motor learning induces structural spine plasticity in the cerebellar Purkinje neurons, which may play a crucial role in acquiring complex motor skills.     

The psychology of diaspora experiences: intergroup contact, perceived discrimination, and the ethnic identity of Koreans in China

The moderating role of intergroup contact on the relationship between perceived discrimination and ethnic identity was examined in a diaspora community of Koreans living in China. It was hypothesized that Koreans with higher intergroup contact would have a lower ethnic identity under higher discrimination, whereas Koreans with lower intergroup contact would have a higher ethnic identity. Across two separate college samples, Koreans who were more willing to interact with Han Chinese had a lower ethnic identity when discrimination was higher, but this finding was not replicated within one college setting. These findings challenge the linear rejection-identification model and suggest displaced people may minimize ingroup-outgroup differences, depending on their willingness to seek intergroup contact.     

Analysis of Pelvis-Thorax Coordination Patterns of Professional and Amateur Golfers during Golf Swing

The aim of this research was to quantify the coordination pattern between thorax and pelvis during a golf swing. The coordination patterns were calculated using vector coding technique, which had been applied to quantify the coordination changes in coupling angle (γ) between two different segments. For this, fifteen professional and fifteen amateur golfers who had no significant history of musculoskeletal injuries. There was no significant difference in coordination patterns between the two groups for rotation motion during backswing (p = 0.333). On the other hand, during the downswing phase, there were significant differences between professional and amateur groups in all motions (flexion/extension: professional [γ] = 187.8°, amateur [γ] = 167.4°; side bending: professional [γ] = 288.4°, amateur [γ] = 245.7°; rotation: professional [γ] = 232.0°, amateur [γ] = 229.5°). These results are expected to be a discriminating measure to assess complex coordination of golfers' trunk movements and preliminary study for interesting comparison by golf skilled levels.