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861.
R B Margolis N R Williger C L Greenlief E J Dunn J D Gfeller 《The Journal of psychology》1989,123(2):179-186
We investigated the sensitivity of the Bender (1938) Visual-Motor Gestalt Test (BGT) using the Halstead-Reitan Neuropsychological Battery (HRB) as the criterion for cortical dysfunction. We studied 95 subjects over age 55 who had been diagnosed as having dementia or pseudodementia. Subjects were classified as mild, moderately, or severely impaired on the HRB and as impaired or unimpaired on the BGT. The results indicated that the BGT is less sensitive (36%) than was expected when used on an impaired geriatric population. The data further indicated that false negatives occurred more frequently with the BGT when individuals had mild neuropsychological impairment. Less frequent misclassifications occurred as the severity of impairment on HRB indices increased. 相似文献
862.
Delusions and hallucinations reported in the social histories of 150 patients admitted to an East Texas state hospital during the 1930s and of 150 patients admitted during the 1980s were examined for content that would characterize and contrast the patient subcultural milieu of the two time periods. Patients admitted during the 1930s tended to reflect the material deprivation and personal powerlessness of the great depression in delusions of great wealth and positive "special powers." The hallucinatory visions and voices of the 1980s patients reflected a more threatening and negative subcultural milieu, with more visions of blood, snakes, and dead people or animals. Command hallucinations to hurt, to kill, or to do "perverse things" would also suggest that the subculture milieu of the 1980s had become more dangerous. 相似文献
863.
Little research has been conducted on Loevinger's Washington University Sentence Completion Test of Ego Development in adult psychiatric outpatients. The measure is a promising method of assessing a construct of personality and character functioning that should be useful in research on psychopathology and in choosing treatment modalities. The data presented in this study address the question of the psychometric adequacy of the measure in this segment of the subject population. Specifically, estimates of interrater reliability, internal consistency, and test-retest reliability are presented for a sample of 42 adult outpatients. In addition, the relationship between total protocol ratings and item sum scores is explored. 相似文献
864.
Recent empirical work aimed at identifying test signs of borderline personality disorder is reviewed. The review focuses on commonly employed clinical tests, including the Wechsler Adult Intelligence Scale (WAIS), the Rorschach, and the Minnesota Multiphasic Personality Inventory (MMPI). Possible test signs are considered in relation to their sensitivity to and specificity for the diagnosis and in relation to the criteria of DSM-III, which define the disorder. Although consistent patterns of potentially useful test signs have begun to appear, methodological difficulties have hampered any subsequent development of clinically useful indices. Greater attention to sample size and its composition and definition as well as demonstrations of adequate reliability and predictive utility are required for further development of these signs. 相似文献
865.
Sonuga-Barke EJ Lea SE Webley P 《Journal of the experimental analysis of behavior》1989,51(2):185-197
Two experiments were carried out in which children's sensitivity to changes in reinforcer density (number of reinforcers per session) was measured in a choice paradigm. In Experiment 1, 24 girls (ages 6, 9, and 12 years) performed on concurrent-chain schedules of reinforcement. The initial links were variable-interval 10-s schedules. One terminal link always gave three tokens after 30 s, but the parameters associated with the other were varied. Independent manipulations of reinforcer size (two tokens or four tokens) and prereinforcement delay (25 s or 65 s) led to equal changes in the relative density of tokens that could be earned on the schedules. Subjects at all ages were sensitive to changes in reinforcer density brought about by changes in reinforcer size, whereas only 3 12-year-olds showed sensitivity to the changes brought about by manipulation of prereinforcer delay. In Experiment 2, titration procedures were used to test the extent of this insensitivity to delay in 32 6- and 12-year-old children. In these procedures, a repeated choice of the large reinforcer increased the delay to its delivery, and a repeated choice of the small reinforcer reduced the delay to the delivery of the large reinforcer. Whereas 6-year-old boys and girls tended to maintain a strong preference for the large reinforcer, so increasing the delay to its delivery, 12-year-olds tended to distribute their responses to both alternatives, thus producing a stable level of delay to the large reinforcer. The results from the two experiments support the idea of two stages in the development of adaptive intertemporal choice. 相似文献
866.
The peak procedure was used in two experiments to study pigeons' ability to time multimodal events. In the first experiment, birds were trained to time a single event consisting of a 9-s tone or light followed by a 21-s fixed interval associated with a signal of light or tone (signal of the other modality). On occasional empty trials, different lengths of the first signal were followed by a long period of the second signal. Peak response times as a function of the duration of the first signal were linear and had a slope of close to one in all birds. This indicates that the birds were timing only the second signal. In a second experiment, two complex events were used in training. One consisted of a 9-s tone or light followed by a 21-s fixed interval associated with a light or tone. The other consisted of a 21-s tone or light followed by a 9-s fixed interval associated with a light or tone. Different durations of the first signal were again used on empty trials. Peak response times as a function of the duration of the first signal were again linear in all birds. The slope of the function was less than one but greater than zero for 3 birds. This indicates that these birds were partly timing the entire complex event of 30-s duration and partly timing only the second signal of the event. A model is proposed in which the bird takes as a criterion for timing a weighted average of different target criteria. Comparisons with the performance of rats are made. 相似文献
867.
Kehoe EJ 《Journal of the experimental analysis of behavior》1989,52(3):427-440
Models containing networks of neuron-like units have become increasingly prominent in the study of both cognitive psychology and artificial intelligence. This article describes the basic features of connectionist models and provides an illustrative application to compound-stimulus effects in respondent conditioning. Connectionist models designed specifically for operant conditioning are not yet widely available, but some current learning algorithms for machine learning indicate that such models are feasible. Conversely, designers for machine learning appear to have recognized the value of behavioral principles in producing adaptive behavior in their creations. 相似文献
868.
Sidman M Wynne CK Maguire RW Barnes T 《Journal of the experimental analysis of behavior》1989,52(3):261-274
Three adult subjects were taught a set of two-choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within-class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two-choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within-class conditional relations after the equivalence tests. 相似文献
869.
Spijkers WA 《Journal of motor behavior》1989,21(3):207-224
The effects of instructed movement speed were investigated in two experiments. First, rapid-timing and single-aiming movement tasks were compared. Unlike rapid timing, single aiming implies spatial accuracy. The aim of the first experiment was twofold: (a) to examine whether the requirement of accurate placement termination in single aiming affects the negative relationship between instructed average velocity and reaction time found in rapid timing, and (b) to test the speed-accuracy relationships predicted by the symmetric impulse variability model of these movement tasks. For this purpose, four average velocities (5, 24, 75, and 140 cm/s) were investigated in both types of movement tasks in a two-choice reaction task. The effects of average velocity on reaction time were similar in both single-aiming and rapid-timing tasks, and the predicted linear relationship between instructed average velocity and spatial accuracy was not found. The results suggest that the movement control mode, that is, open loop or closed loop, interferes with effects of instructed average velocity. The movement control mode explanation was confirmed in the second experiment with respect to the effect of paired velocities on reaction time. It is argued that the type of movement control mode must be considered in the interpretation of effects of instructed average velocity on reaction time and spatiotemporal measures. 相似文献
870.
Adults are able to use a visual target to reduce quiet-standing postural sway (Lee & Lishman, 1975). The present study was designed to determine whether children, under varying postural conditions, are also able to use a visual target to reduce postural sway. A second purpose was to determine the ability of children to visually fixate under different postural conditions. An inability to visually fixate may limit the usefulness of a visual target. The results indicate that, like adults, children are able to reduce sway in the presence of a visual target. Young children are less able than older children and adults to visually fixate. In addition, children show more spontaneous visual saccades in the no-target condition than in the target condition and more saccades in the Romberg stance than in a feet-together stance. The fact that saccades decrease with increasing age, even in the seated, head-stabilized condition, precludes the possibility that increased instability of the young children is the only cause of increased number of saccades. 相似文献