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11.
A method of constructing digital filters is outlined and illustrated in an application for research uses of EEG feedback. The method is based on least squares estimation with geometric weighting. Old data in the time series are discounted according to age, as new data arrive. Recurrence relations are used, allowing the computations to be performed in real time. A FORTRAN digital filter is formulated that simultaneously estimates (1) the spectral power in a band centered at a target frequency, (2) the total spectral power, and (3) the dominant frequency.  相似文献   
12.
The author conceptualizes a pattern of thought and behavior that can be called the escape-to-Israel syndrome. This pattern is a contemporary variety, appearing primarily in the Jewish population, of the geographic cure: that is, one can solve one's personal dilemmas by moving from one place to another. The syndrome is characterized by a tendency to idealize life in Israel. This idealization, and the viewers' fantasy of their own future in Israel, deflect solid confrontation with genuine personal problems. If, in fact, they do move to Israel, they may experience shock and trauma at the gap between expected reality and the discovered one. This may only compound their emotional difficulties.The author wishes to express his gratitude to Professor Shamai Davidson, Clinical Director of the Shalvata Mental Health Center, Hod HaSharon, Israel, for his critical comments during the preparation of this article.  相似文献   
13.
14.
The development and psychometric investigation of the Perceived Support Network Inventory (PSNI), a measure of perceived social support, is described. A group of 146 introductory psychology students participated in a test-retest study design that collected reliability, internal consistency, and construct, convergent, and discriminant validity data on the scale. In addition, a contrast group of 28 Counseling Center clients was administered the PSNI. Test-retest reliability of the PSNI total score and subscale scores ranged from .72 to .88. Internal consistency for the PSNI was .77. Construct validity estimates ranged from .21 to .57. Convergent validity estimates varied from -.25 to .20. Discriminant validity estimates varied from -.11 to .19. Sample differences between introductory psychology student mean PSNI total and subscale scores and Counseling Center client mean PSNI total and subscale scores proved significant. Recommendations for subsequent research and future application are offered.  相似文献   
15.
Inexpensive speech synthesizers are now available that either plug into the card slots on computers or connect to their serial ports. With some practice in listening, the speech produced by these synthesizers is quite intelligible, and because they present information that appears on the screen of the monitor, they make it possible for blind persons to interact with computers. However, they provide only a partial solution. In too many instances, some of the text appearing on the monitor screen cannot be directed to the synthesizer, and the missing information is often crucial. This happens because the writers of application programs sometimes modify the computer’s disk operating system. This limitation can be overcome by using special hardware that reads the screen buffer directly and creates a virtual image of the screen in memory external to the computer. Because the image is updated continually, it is always an accurate representation of whatever appears on the screen. The characters contained in the external buffer can be sent to a speech synthesizer, and can be examined selectively by means of a small keyboard. Several successful hardware solutions have been demonstrated, and one of these solutions is described here in detail.  相似文献   
16.
Summary Previous research has demonstrated that the emotional properties of words and their imaginability affect their recallability and that verbal material is recalled better when it is related to subjects' current concerns. This study investigates the extent to which this effect of emotion on recall varies as a function of cognitively controllable inference processes and examines the relation of the effects of emotion to those of imaginability and concern-relatedness. Forty different words were presented visually under one of six orienting conditions that varied according to what the subject was asked to rate: their length, pronounceability, concreteness, defineability, the strength of emotion elicited by the word, and the relation of the word to personal concerns. Subjects were then asked to write as many words as they could recall. Words that aroused stronger emotion and were easier to represent in imagery were recalled better than emotionally less arousing and imaginally less evocative words, regardless of the nature of the orienting task. The evidence suggests that the emotional properties of words are evaluated automatically in an early processing stage, without requiring subjects to reflect on word content. Emotional arousal appears to mediate the effects of current concerns on recall. It is correlated with but appears to function independently of word imaginability.  相似文献   
17.
The differences in apparent prevalence of childhood hyperactivity between England and North America are more than 20-fold. This paper seeks to illuminate the reasons for the difference by applying a standard measure [Conners Teacher Rating Scale] to 437 English schoolchildren, aged 6 to 9 years, and comparing them with published surveys from the United States and Australasia. The rating scale had moderate interrater reliability and stability over time; it distinguished between children referred for psychiatric treatment and normal schoolchildren. Component analysis yielded a factor of hyperactivity-inattentiveness, distinct from conduct disorder. The mean hyperactivity scores of English children were higher than in most U.S. surveys but lower than in New Zealand. The national differences in rates of diagnosed hyperactivity are likely to reflect diagnostic inconsistency rather than true differences in children's behavior.  相似文献   
18.
This experiment examined whether structural considerations, that is the functional closeness of limb control centres (Kinsbourne and Hicks 1978), have a role to play in common processing models of psychological refractoriness. A typical double stimulation paradigm was used (Kantowitz 1974). On experimental trials, subjects responded with the right hand (RT1) to an auditory signal (0.80 probability). After a varied interstimulus interval (ISI) of 100, 200, 300 or 700 msec, one of three lights corresponding to one of the other limbs provided the signal for the second response (RT2). Control trials for RT1 and RT2 involved both stimuli, but subjects were required to make only one response. Results indicated that experimental RT1 was lengthened considerably over control values. While typical double stimulation effects were found at short ISIs, that is RT2 was lengthened, RT2 at long ISIs was actually faster than double stimulation control values. Although the RT results were not in a pattern that would be predicted by functional distance (Kinsbourne and Hicks 1978), within subject correlations of RT1 and RT2 by limb condition suggest that structural considerations may have a role to play. While within subject correlations were positive at all levels of ISI, they decreased as the interval between the two signals increased. The implications of these results for common processing models are discussed.  相似文献   
19.
In addition to being an unusual form of crime, sexual homicide (SH) sometimes includes unusual crime scene behaviours, such as carving on the victim, evisceration (i.e., removal of internal organs), skinning the victim, cannibalism and vampirism. The current study investigates these unusual crime scene behaviours to better understand their meaning as well as to explore whether such behaviours are associated with a specific crime-commission process. Using a sample of 762 SH cases, the study uses a combination of chi-square and stepwise forward logistic regression analyses to identify the differences between cases with and without unusual acts. Findings reveal that SH cases with unusual acts present a specific crime-commission process. This crime-commission process is characterised by a greater level of sadism—as demonstrated by the presence of mutilation and foreign object insertion—as well as a greater level of organisation from the selection of a contact location where the risk of being seen or heard was low. These findings provide a better understanding of these behaviours and could help investigators facing such cases.  相似文献   
20.
In one well-known model for psychological distances, objects such as stimuli are placed in a hierarchy of clusters like a phylogenetic tree; in another common model, objects are represented as points in a multidimensional Euclidean space. These models are shown theoretically to be mutually exclusive and exhaustive in the following sense. The distances among a set ofn objects will be strictly monotonically related either to the distances in a hierarchical clustering system, or else to the distances in a Euclidean space of less thann — 1 dimensions, but not to both. Consequently, a lower bound on the number of Euclidean dimensions necessary to represent a set of objects is one less than the size of the largest subset of objects whose distances satisfy the ultrametric inequality, which characterizes the hierarchical model.This work was supported in part by Grant GB-13588X from the National Science Foundation. I would like to thank L. M. Kelly and A. A. J. Marley for their helpful comments and suggestions.  相似文献   
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