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981.
The study examined the effects of degree of paramenstrual distress, signal frequency, task load and time on task on psychomotor performance across the menstrual cycle. Simple reaction time, choice reaction time and pursuit tracking were the tasks employed, and performance was assessed using the metrics of mean level, variability, and errors of omission and commission. The results showed performance as a function of menstrual cycle phase and paramenstrual distress to be highly task and metric specific, a finding typical of stressor variables: pursuit tracking was affected by phase, with mean performance at its worst premenstrually; choice reaction time was dependent on a complex interaction of experimental variables and measurement metrics; simple reaction time showed no significant effects. Patterns of attention allocation in a time-sharing situation combining both pursuit tracking and choice reaction time components were also investigated. Trends here indicated relatively better performance both menstrually and intermenstrually as components increased in signal/response frequency, with a corresponding deterioration premenstrually. Overall performance capacity appeared to be greatest at menstruation, and the degree of attentional selectivity was least. High distress women performed better on low frequency components, whereas asymptomatic women did better at higher signal rates.  相似文献   
982.
A comprehensive test battery was devised to study the effects of right hemisphere lesions on the speech and language of “nonaphasic” dextrals. Data were thus obtained for 62 subjects, 20 of them neurologically healthy and 42 with a focal right hemisphere lesion resulting from a cerebro-vascular accident. A preliminary global analysis of these data is reported. Anomalies were observed in 33 brain-damaged subjects. Although discreet in all cases, these anomalies were shown to have various degrees of severity. Given the population submitted to this study, the subject most likely to show such anomalies was defined, genetically, as a right-handed adult with a family history of ambidextrality or left-handedness and, socially, as one with a relatively limited education. The implications of these findings are discussed together with the problem of the anatomo-clinical correlations of language disorders resulting from right hemisphere lesions in “nonaphasic” dextrals.  相似文献   
983.
It was previously shown and was here replicated that the amount of money required to induce a subject to exchange one gamble for a second and then the second for a third depends on the second (intermediate) gamble. This path dependency cannot be explained by any of the algebraic models (including SEU), nor can it be explained as a simple attention effect. A model was put forward which explains the effect in terms of differential masking depending on a kind of stimulus—response compatibility. The effect of response mode on path dependency was examined in this study; similarity judgements showed no consistent path dependency nor did difference in rated attractiveness of gambles presented in pairs, but rated attractiveness was different for gambles presented singly. Since it might be that monetary response emphasises the monetary aspects, that is, the winning amount of the gamble, it was thought that a probability response would emphasise the probability of winning. However, when subjects were asked to set the probability of winning $ 12 which would induce them to exchange one gamble for another, not only was no path dependency observed, but the subjects' responses seemed to depend only on the difference in expected value of the gambles. This suggests the possibility of developing response-display modes which would eliminate or at least attenuate the inconsistencies observed in risky decision processes.  相似文献   
984.
In a 3 × 2 × 2 factoral experiment, 12 subjects carried out a choice reaction task with reaction time (RT) and movement time (MT) as response measures.Independent variables were drug treatment (amphetamine, barbiturate, placebo), visual stimulus degradation and S-R compatibility. Visual stimulus degradation and S-R compatibility showed additive effect on the RT, but did not affect the MT. This confirms that stimulus encoding, response selection and response execution represent independent processing stages. The two drugs had selective effects on the RT and the MT. Barbiturate (as compared to placebo) had no effect on the MT, but it lengthened the RT, and this effect was additive with the effects of S-R compatibility but showed an interaction with the effects of stimulus degradation. Amphetamine (as compared to placebo) shortened the MT, but there was no significant main effect of amphetamine on the RT although the interaction with the effect of S— compatibility was significant. These results suggest that barbiturate affects stimulus encoding whereas amphetamine affects response-related processes..  相似文献   
985.
Dyslexic and nondyslexic boys within a single community's learning-disabled class were given a set of tests; performance on each of these tests has been reported to be significantly impaired in other dyslexic children compared to learning-disabled and normal groups. Linear discriminant function analysis revealed that error types rather than levels of performance best separated the carefully matched learning-disabled groups. Slow naming and high percentage of “dysphasic” errors characterized dyslexic boys. Visual temporal-spatial matching and “configuration-deficient” perceptual errors characterized the adequate readers who have other learning disabilities.  相似文献   
986.
This study investigated the functional cortical organization of reading-disabled boys and age-matched normal readers. Subjects were initially classified according to E. Boder's (1971a. In B. Bateman (Ed.), Learning disorders. Seattle: Special Child Publications. Vol. 4.) distinction between dysphonetic children (who make nonphonetic, bizarre spelling errors), dyseidetic children (who make phonetically acceptable errors, but do not respond to some words as “wholes”), and children who display normal error patterns (who make phonetically acceptable errors and respond to words as “wholes”). It was hypothesized that different types of reading disability would be associated with different patterns of lateralized brain function. This proposal was examined by testing subjects on three experimental neuropsychological measures—hemispheric time-sharing, conjugate lateral eye movements, and tactile directional perception. Conjugate lateral eye movements were disregarded as the control subjects failed to show predicted asymmetries on this measure. The two other measures were considered valid and demonstrated atypical lateralization in the reading-disabled groups. Lateralization of verbal and/or spatial functiosn differed among the reading-disabled groups and an attempt was made to relate these atypical patterns to the type of reading difficulties presented.  相似文献   
987.
Five rats pressed levers on variable-interval schedules of water reinforcement at various levels of water deprivation. In one phase of the experiment, three deprivation conditions that replicated conditions in Heyman and Monaghan (1987) were arranged, along with three less extreme deprivation conditions. In a second phase, water deprivation was arranged so that subjects were exposed to a greater range of access to water per day. Herrnstein's hyperbola described the rats' response-rate data well. The y asymptote, k, of the hyperbola appeared roughly constant over the conditions that replicated those of Heyman and Monaghan, but decreased markedly when less extreme deprivation conditions were included. In addition, k varied systematically when the second method of arranging deprivation was used. These results falsify a strong form of matching theory and confirm predictions made by linear system theory.  相似文献   
988.
The Marshak bid procedure shows that more money is required to induce a S to exchange gamble a for gamble e and then e for b if e differs from a only in the winning amount and differs from b only in the probability of winning, rather than if e differs from a only in the probability of winning. This is contrary to most theories of risky decision making which imply that the amount of money necessary to effect a 2-step exchange between a and b should be independent of the intermediary gamble. One might attempt to explain the effect by saying that the S attends to the dimension which is different between gambles. But the explanation is untenable if one assumes that states of attention are defined as weightings of the dimensions. An alternative explanation is put forward which basically assumes that winning amounts mask differences in probability of winning more than vice versa. The formalization of the theory is given in terms of Fechnerian integration over imperfect differentials.  相似文献   
989.
The effects of positive and negative interactions on children's performance and preferences for the adults associated with each type of interaction were studied. Five children served as subjects during daily sessions in which each of three adults followed prescribed patterns of social interaction. One adult (positive) dispensed positive comments contingent upon either color-sorting or completion of arithmetic problems; a second adult (negative) mildly reprimanded the child for off-task behavior; and the third adult (extinction or nonreactive) said nothing to the child when he was present. Following each session the three adults reentered and the child chose one of them for an additional period of interaction. Three response measures (frequency, latency, and percent of time on-task) and children's adult preferences were obtained daily. The negative adult affected the most task behavior and had strongest stimulus control; the positive adult, though exerting little control over children's behavior, was the most preferred. Children's adult preferences were not specific to the task setting, but were observed across a variety of contexts.  相似文献   
990.
Three experiments were conducted investigating memory for items and order in a progressive elaboration paired-associates task. For all subjects retention of item information was improved by the use of progressively elaborated interactions relative to a no-elaboration control condition. For second and fourth graders, retention of order information depended upon the type of elaboration. If successive interactions were added in a logical temporal order, retention (of order information) was superior to the case where the successive interactions were added in a random order. This effect was not obtained with kindergarten children. In the second and third experiments, kindergarteners were instructed regarding the sequencing of the successive items, and results similar to those obtained with older children ensued. The data were discussed in terms of Tulving's distinction between episodic and semantic memory.  相似文献   
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