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961.
In order to investigate the proposal that modifications in developmental rate may mediate differences in aggressive behavior, two series of selective breeding studies were completed. Stable lines of mice that differed in the frequency and latency of attacks were rapidly established in two series (by S1 in the first series and S3 or S4 in the second series). For evaluation of the developmental-genetic proposal, an analysis was made of the ontogeny of aggressive expression in male mice of the two series, with a detailed report provided of the S1 and S4 generations of the second breeding series. Comparisons between the results of a longitudinal design and the results of a new type of cross-sectional design (involving only siblings, or co-sibial) indicated (a) a reliable developmental course of attack expression, with a sharp rise in early maturity and a slow decline thereafter; (b) a convergence in later maturity of the behavior of lines selectively bred for high or low aggressive behavior, if the animals had been assigned to the longitudinal design; (c) a strong effect of repeated testing on attack latency and frequency, even though the dyadic tests were brief in duration and separated by long intervals. In addition, cross-generational comparisons suggested that the selective breeding differences came about primarily by changes in the behavior of the low aggressive lines, in that these animals failed to show in early maturity the sharp increases in attack occurrence that were observed in earlier generations. Certain implications of these findings for developmental and evolutionary concepts (e.g., neoteny, acceleration, heterochrony) are discussed.  相似文献   
962.
Electrographic (EEG, EOG, EMG) indices have been used for some decades in the definition of the stages of sleep and more recently in the diagnosis of sleep-related disorders, e.g., insomnia, despite the lack of detailed information concerning the precise relationship between such electrographic indices and behavioral and subjective criteria of sleep. Evaluation of the relationship between EEG, behavioral, and self-report measures of sleep onset latency and sleep duration was conducted using 17 young normal sleepers. The behavioral measure was provided by an apparatus which records subjects' button-press responses to an auditory stimulus presented at various interstimulus intervals (2, 5, and random 1, 2, 5, 7, and 10 min). The behavioral and stage 2 EEG estimates of sleep onset latency (SOL) and sleep duration (SD) were almost identical. The stage 1 EEG provided the shortest estimate of SOL; the self-report measure, the longest. The SD measures were in reverse order. There were no significant differences among the three interstimulus interval conditions (2, 5, and random min). Average response rates to the 50-dB chime were 100% during wakefulness, 81% during EEG stage 1, and 8% during EEG stage 2. Almost all stage 2 responding occurred during the first 5 min of each stage 2 period. The validity of electrographic indices as sleep criteria and the implications of the findings for the formulation of an adequate definition of sleep and its clinical measurement are discussed.  相似文献   
963.
The Gestalt studies demonstrated the tendency to visually organize dots on the basis of similarity, proximity, and global properties such as closure, good continuation, and symmetry. The particular organization imposed on a collection of dots is thus determined by many factors, some local, some global. We discuss computational reasons for expecting the initial stages of grouping to be achieved by processes with purely local support. In the case of dot patterns, the expectation is that neighboring dots are grouped as a function of proximity and similarity of contrast, by processes that are independent of the overall organization and the various global factors. We describe experiments that suggest a purely local relationship between proximity and brightness similarity in perceptual grouping.  相似文献   
964.
Excitability in a cortical representation of a foreleg was determined during elaboration of transswitching in dogs in three variations depending upon the stimulus used as a Conditioned stimulus (CS). If the flexor reaction to direct stimulation of the motor cortex was used as a CS, excitability changes of opposite signs appeared in the cortical representation of the foreleg, the threshold of flexion decreased in the alimentary situation and increased in the defense situation. Such changes in excitability were observed during instrumental conditioned transswitching. If subthreshold stimulation of the motor cortex was used as the CS, the threshold of flexion increased in both situations in approximately equal degree.  相似文献   
965.
This study demonstrated the use of quantitative content validity procedures in the development of a job-related behavioral rating scale criterion for entry-level psychiatric aides. Work behavior items were developed by staff from 6 state psychiatric hospitals, placed in a content validity questionnaire using the Lawshe format, and given to a representative sample of 38 aides and supervisors. Seventy-eight of 83 items were found to be significantly job-relevant using the computation procedures of both Lawshe and Aiken. After the significant items were grouped into 4 categories with high interjudge agreement and placed in a rating scale format, ratings were obtained on 72 psychiatric aides from 4 hospitals. Items in the 4 categories were found to be internally consistent using coefficient alpha. Significant but low concurrent validities were established for 2 verbal ability selection tests using the rating criterion. The validities found were interpreted to be especially significant when the factors of low selection ratio, restriction in range, and limited rater training were considered.  相似文献   
966.
Glutamate is believed to be quantitatively the most outstanding of the excitatory transmitters in the CNS. Certain conformationally related analogues, e. g. kainate, N-methyl-D-aspartate, ibotenate, and homocysteate, act as glutamate agonists. The local or systemic administration of these "excitotoxic" compounds induces epileptiform activity pointing out new and deeper insights into the epileptic process. Additionally, the glutamate transmitter hypothesis is expected to give a chance of a causal comprehension for choreatic processes as well as for the mode of action of anticonvulsant and antispastic agents.  相似文献   
967.
Two simple sociometric techniques for practical use are described which are derived from the data given in the sociogram. Compared with the conventional sociogram, the group rank score we use everyday therapy has the advantage that it can be published. It permits members of the group to better identify the social situations which cause specific psychic impulses. The sociogram is reserved for the therapist. In our opinion the sociodynamogram has certain advantages over both methods because it provides an insight into spheres which are inaccessible in the sociogram and group rank score.  相似文献   
968.
The levels of 20 amino acids were measured in the plasma and cerbrospinal fluid of 41 patients with endogenic depressions. The plasma levels of 12 amino acids were found to be significantly lower in the patients than in the control group, but cerebrospinal fluid levels were significantly lower only in the case of taurine, glutamine, phenylalanine and aginine. Comparison of the same amino acid levels in treated and non-treated patients showed that serine and alpha-aminobutyric acid serum concentrations were higher in the nontreated patients. The tyrosine and phenylalanine levels in the cerebrospinal fluid of the patients who had received medicamentous treatment were higher than in the other group.  相似文献   
969.
970.
Nondeterministic programs occurring in recently developed programming languages define nondeterminate partial functions. Formulas (Boolean expressions) of such nondeterministic languages are interpreted by a nonempty subset of {T (“true”), F (“false”), U (“undefined)}. As a semantic basis for the propositional part of a corresponding nondeterministic three-valued logic we study the notion of a truth-function over {T, F, U} which is computable by a nondeterministic evaluation procedure. The main result is that these truth-functions are precisely the functions satisfying four basic properties, called \( \subseteq \) -isotonic, \( \subseteq \) ?-isotonic, hereditarily guarded, and hereditarily guard-using, and that a function satisfies these properties iff it is explicitly definable (in a certain normal form) from “if..then..else..fi”, binary choice, and constants.  相似文献   
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