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21.
Fourier analysis describes the amount of variation in a time series by partitioning it into sinusoids of different amplitudes and wavelengths and quantifying the extent to which these waves are synchronized. The importance of a given wave is represented by its contribution to the explained variance of the time series. To illustrate its potential application to the study of movement, Fourier analysis was used to quantify the movement patterns of 2 pigeons on a variable-interval (VI) and a variable-time (VT) schedule of reinforcement. For comparison, the movements of 2 pigeons that did not receive reinforcement were similarly analyzed. Characteristic frequencies were higher during VI than during VT, and relatively low during nonreinforcement. We concluded that Fourier analysis can be used to represent movement patterns compactly, study their periodicity, stereotypy, and resonance, and assist in computer simulations and models of movement.  相似文献   
22.
Judged distance in a large open field, scaled by the method of magnitude estimation, is related to physical distance by a power function with an exponent smaller than unity. The exponents obtained with two ranges of distance were not affected by the availability of a standard. The mean exponent for all 80 individual power functions was 0.86, with a standard deviation of 0.11.  相似文献   
23.
Several studies have shown a negative linear relationship between speech rate and memory span. This relationship has implications for bilingual studies, as span could be larger in a bilingual's secondary language provided that pronunciation rate is faster than in the mother language. The purpose of this study was to investigate the effects of digit word length on digit span in bilinguals. Experiment 1 tested the effects of digit syllable length on speech rate in five different bilingual groups. Results revealed that digit-reading rates were significantly faster in all mother languages. Experiment 2 examined more closely the correspondence between speech rate and digit span with Portuguese-English bilinguals. Results showed that digit-reading rates were faster and digit span larger in the mother language even if the mean number of syllables per digit was higher. The superiority of mother tongue was discussed according to the view that digits are subject to massive practice in one's native language with a strong tendency to be abbreviated, thus reducing its spoken duration.  相似文献   
24.
This study investigated the relationship between manifest handedness and the localization of EEG abnormalities in a large group of mentally retarded persons. Persons who had abnormal EEG recordings, regardless of whether the dysfunction was bilateral or asymmetric, exhibited approximately twice the incidence of left-handedness than persons who had normal EEG's. Data for persons having asymmetric damage support a model of pathological left-handedness, with left-handers showing a substantially higher probability of having left brain dysfunction than right-handers.  相似文献   
25.
Current Psychology - Based on Farber’s burnout proposal, the first aim of this study was to examine the psychometric properties of the short version of the Burnout Clinical Subtype...  相似文献   
26.

Prenatal smoke exposure (PSE) is a risk factor for adverse outcomes in the offspring, including those affecting psychological development. However, it is uncertain whether these associations are the direct result of PSE or other confounding factors. The aim of this study was to examine the possible relationship between PSE and behavioral development in children at 7.5 years of age, considering several prenatal, neonatal and postnatal covariates. A cohort of 266 mother-child pairs was followed from the first trimester of pregnancy until the children reached 7.5 years of age. PSE was assessed using a questionnaire from prenatal clinical records and corroborated by plasma cotinine determinations in the first and second trimesters and in the cord. Mother-child pairs were classified into one of four groups: unexposed, exposed to passive smoking, first trimester active smoking only and active smoking throughout pregnancy. Child behavior was assessed using the Child Behavior Checklist for ages 6–18 and the Childhood Autism Spectrum Test. In multiple linear regression models, smoking during pregnancy was associated with higher scores in affective problems (β?=?0.298; p?=?0.004). No significant associations were found between smoking during pregnancy and externalizing problems. Findings indicate that PSE is negatively associated with behavioral development in childhood.

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The automatic skeletal motor responses of 20 male and 20 female student subjects (aged 20–36) receiving a painful stimulation (electric shock) were studied by examining voluntary concomitant extensions and flexions of the arm. These movements were either of long duration, allowing for an on-line control of their execution or, of short duration, requiring extensive pre-programming. Subjects were instructed either to push or to pull a lever upon receipt of an acoustic signal, which was paired or unpaired with an electric shock. Latencies for long duration movements (regardless of direction) were reduced by reception of painful stimulation. Latencies of short duration extensions and flexions were respectively reduced and increased by painful stimulation. Latencies of short duration movements were larger for females than males, regardless of movement direction. These data suggest that painful stimulation elicits automatic movements which affect programming of the termination of simultaneous voluntary movements. Implications of these findings for the study of aggressive behavior are discussed. © 1994 Wiley-Liss, Inc.  相似文献   
29.
Viktor J. Tóth 《Dialog》2020,59(4):352-355
This article focuses on the third volume of Vel-Matti Kärkkäinen's systematic theology, titled Creation and Humanity. After a brief overview of the volume the article offers some clarification on the tenth chapter, especially on its interaction with paleontology. After that, two constructive observations follow. The first is related to Kärkkäinen's notion of the embeddedness of human nature, and the second is to further employ systems thinking in his constructive work on creation and human evolution.  相似文献   
30.
In this article we identify three previously unnoticed problems with flexible moral theories, i.e., theories according to which different moral rules apply when there is full compliance and when there is partial compliance. The first problem is that flexible theories are necessarily very complex, which undermines their ability to motivate and guide action. The second problem is that flexible theories allow for a troubling kind of (moral) domination: the duties an agent has depend on other agents' willingness to comply. Finally, flexible theories introduce indeterminacy: it is sometimes impossible to determine which moral rules apply. When agents stand at the threshold—i.e., when a different rule would apply if a single additional act of noncompliance took place—it is impossible to determine which rule should apply.  相似文献   
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