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981.
A system of interfaces for the Commodore 64 (C-64) microcomputer for use in the operant laboratory is described. This system frees the experimenter from limitations on the number of I/O lines available on the user port of the C-64 and offers the control of operant chambers for a low cost. Subroutines in machine code to control the interfaces, offering millisecond timing of external events, are presented. A sample BASIC program demonstrates how the subroutines are called from BASIC to run a simple discrimination experiment.  相似文献   
982.
Pascal routines are described for several real-time operations on Macintosh computers. Methods are presented for millisecond timing and for high-speed transfer of arbitrary bit-image displays to the screen. All routines are based on Toolbox procedures available on virtually all Macintosh computers.  相似文献   
983.
In this paper, we describe software that turns a Macintosh computer into an off-the-shelf tool for experiments on visual search. Our design goals included portability (between members of the Macintosh computer family and between various research settings), user-friendliness (equivalent to Macintosh programming standards), flexibility (to allow replication and extension of important experiments on visual search), and adaptability (very short design-to-data and data-to-analysis turnaround times). We describe how the software meets these goals in three major phases of an experiment: stimulus construction, experimental control, and statistical analysis. We then list several landmark studies of visual search that can be easily designed and extended with the software. Finally, we outline plans for expanding the experimental variations that will be supported in future versions of the software.  相似文献   
984.
This paper examines the ethical issues of conflict of interest raised by the burgeoning development of physician involvement in for-profit entrepreneurial activities outside their practice. After documenting the nature and extent of these activities, and their potential for conflicts of interest, the paper assesses the major arguments for and against physicians' referral of patients to facilities they own or in which they invest. The paper concludes that an outright ban on such activity seems ethically warranted.  相似文献   
985.
The orienting response (OR) is a specific behavioral act directed towards extraction of information from the environment. Head and eye movements represent only the tip of the iceberg of internal responses, which includes vascular modifications, EEG changes, and event-related potentials. Two mechanisms of the OR have to be differentiated: voluntary and involuntary. In the event-related potential, such a differentiation is expressed in mismatch negativity (involuntary effect) and processing negativity (voluntary effect). Single unit studies have shown that hippocampal neurones are simulating specific features of the OR as a response to novelty. Repeated presentation of stimuli results in a selective habituation of novelty detectors in hippocampus and of the OR. The trace of a standard stimulus formed at the level of hippocampal neurones matches the features of the standard stimulus and can be called a “neuronal model of the stimulus.” The OR is triggered by mismatch between the test stimulus and the elaborated neuronal model, and is activated by verbal instruction, by reinforcement during the initial stage of conditioned reflex elaboration, and by differentiation of signal and non-signal stimuli. A promising new area of practical application of the OR lies in the evaluation of a corridor of optimal functional state for efficient computer-based learning. Registration of the OR and defensive responses can be used for an objective evaluation of the functional state of the student, or, in a wider sense, of the industrial operator. New avenues of OR research are opened by recent techniques that isolate single-trial event related potentials, and their correlation with autonomic and behavioral manifestations of the OR. The combination of single unit recording with such isolated event related potentials can elucidate the neuronal basis of OR generation. Intracellular recording combined with dye injection can be used for analysis of the synaptic contacts involved in generation of the OR. Integration of macro and micro levels of OR organization can be achieved in a computerized model that can be used for simulation and planning of experiments. A step-by-step improvement of the model will accumulate knowledge about the OR as an important mechanism of information processing.  相似文献   
986.
A structured interviewing system was developed which included an item bank of pre-written past-behaviour questions. Scoring anchors for each of 168 questions in the item bank were created from analysis of protocols from individual assessments. A concurrent validation study was conducted, focusing on the job of highway patrol sergeant. Job knowledge experts used a job analysis tool to select a subset of twelve questions from the item bank. Panel interviews were conducted with 32 highway patrol sergeants as subjects. Average inter-rater reliability was 0.65 and interview validity was 0.42 for group consensus scores and 0.44 for panel average scores. Discussion focused on practical issues affecting the interviewing system.  相似文献   
987.
This paper examines the effects of person-centered theory on contemporary psychological testing. Seven basic ideas or assumptions, which are integral to and guide the testing process, are identified and briefly discussed. Each idea is considered to have been affected either directly or indirectly by person-centered philosophy. Some of the ways in which these ideas are reflected in contemporary testing practice are indicated.  相似文献   
988.
Depression in some patients with spinal cord injuries may be clinically significant and, when present, should be treated to decrease morbidity including decreased physical functioning. Depression associated with spinal cord injury (SCI) may be misevaluated, due to (1) nonspecific multifactorial production of depression symptoms and (2) SCI-specific decrease in somatic sensory central nervous system input. The Somatic Suppression Hypothesis suggests that SCI patients have difficulty experiencing any intense emotion because of suppression of physiological arousal. In addition, cognitive processes that may reduce depression in SCI patients include: (1) attribution of somatic symptoms of depression to medical (biological) causes, (2) realistic, positive expectations for physical improvement, and (3) the perception that the disability of the SCI is only minimally related to the patient’s self-care after complete evaluation. Health personnel should accept lack of depression in SCI, and should encourage positive realistic expectations of recovery.  相似文献   
989.
Subjects had to make a “remove” or “do not remove” life-sustaining measures decision in three right to die cases where the patients differed in competence; for half the subjects, a living will was present in all the cases, whereas, for the other half, it was not. Subjects also gave their determinative reasons for their decisions. Support for the right to die varied by case, but not by competency, or by the presence of a living will. The subjects' reasons were highly predictive of their decisions, and related to the way case-specific facts were construed, revealing a number of disparities between the way courts and citizens construe whether the patient's condition is “terminal,” “irreversible,” and “painful,” or not. Beyond construing facts differently, the results also revealed a disparity between evolving case law and the community's “common sense justice” over a fundamental belief: whether dying is seen as private matter, outside the bounds of State intervention, or not.  相似文献   
990.
The disambiguation of threat/neutral homophones was investigated in high- and low-trait anxiety subjects who had been exposed to either a positive or a negative mood manipulation procedure. Subjects were required first to spell each auditorily presented word and second, to generate and speak a sentence using the word. Difference indices were calculated for the spelling and the sentence usage data, i.e. the number of threat minus neutral interpretations. Examination of these indices revealed that subjects exposed to the negative mood manipulation procedure produced relatively more threat than neutral interpretations (for both spelling and sentence usage) than did subjects exposed to the positive mood manipulation procedure. Multiple regression analyses revealed that both the trait anxiety and mood manipulation variables contributed significantly to the prediction of the difference index on the spelling task. In the analysis of the use of homophones in sentences, only the mood manipulation variable contributed significantly to the prediction of the difference index on the sentence usage task.  相似文献   
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