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An infrared system for the detection of a pigeon''s pecks at alphanumeric characters on a TV screen: the dependency of letter detection on the predictability of one letter by another. 下载免费PDF全文
H D Clauson E J Izatt C P Shimp 《Journal of the experimental analysis of behavior》1985,43(2):257-264
Three pigeons pecked at letters of the alphabet and at the symbol "?" displayed on a computer-driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon''s responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol "?" appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three-character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol "?" to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism''s acquired knowledge changes what it sees. 相似文献
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Nina Zanetti Levita D'Souza Phillip Tchernegovski Sarah Blunden 《Infant and child development》2023,32(1):e2369
A systematic review of qualitative studies was conducted to explore how parents perceive sleep quality in their infants aged 0–24 months and the factors that influence these perceptions. A systematic search of the databases Scopus, Embase, Cinahl, PsycInfo and MEDLINE, was undertaken to identify eligible peer-reviewed studies published between 2006–2021. Ten papers met inclusion criteria and were subsequently included in the review. Evaluation of papers with the Critical Appraisal Skills Programme qualitative checklist classified papers as weak, moderate or strong, with half considered strong. Thematic synthesis identified one superordinate theme, culture, and five interrelated subordinate themes regarding how parents perceive their infant's sleep and the factors that may influence these perceptions. These themes were: (1) Infants physical and emotional comfort; (2) Beliefs regarding safety; (3) Parental and familial wellbeing; (4) Perceived degree of infant agency; (5) Influence of external beliefs and opinions. The findings from this review may assist practitioners in providing parents with personalized and culturally sensitive information regarding infant sleep and may also inform antenatal and early intervention practices, subsequently minimizing parental distress regarding infant sleep patterns. 相似文献
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Sudden infant death syndrome (SIDS) is defined as the sudden and unexpected death of an apparently healthy infant under 1 year of age. Routine autopsies often provide few clues as to the cause of death and rarely include a biochemical evaluation. Genetic counseling for SIDS can be difficult as recurrence risks vary depending on the age at death and the number of deaths which have occurred in the family. Biochemical disorders may account for up to 5% of SIDS. Of the metabolic disorders known to be involved in SIDS, the most commonly found is medium-chain acyl CoA dehydrogenase deficiency (MCAD). MCAD is an autosomal recessive disorder of fatty acid oxidation which accounts for up to 1% of SIDS. For some families, the addition of a postmortem biochemical investigation can identify an unsuspected metabolic disorder as the cause of death. Once the diagnosis is established, accurate genetic counseling can then be provided. Metabolic testing of the surviving siblings of victims of sudden death, and the subsequent identification of those due to MCAD can prevent the tragedy of recurrent SIDS in some families. In addition, screening the survivors of an acute life threatening event (ALTE) may also prevent a recurrence. 相似文献
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An adult, with a puppet held at shoulder height on either side (within the infant's visual field), interacted with 3- to-6-month-olds, turning her head intermittently to talk to a puppet. Seventy- three percent of infants' first eye-turns were in the direction of the adult head-turn. 相似文献
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An habituation/dishabituation paradigm demonstrates that 2- and 4-month-old infants are able to discriminate auditory sequences that vary slightly in tempo. Discriminations were only observed for intermediate tempi (600 ms but not 100, 300, 1500 ms IOI), suggesting that infants have the same optimal tempo range as adults. 相似文献
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婴儿共同注意能力的发展 总被引:5,自引:0,他引:5
本研究采用严格的实验室测验法,从年龄趋势、学习能力、性别差异三方面考察了8~11个月婴儿共同注意能力的发展。结果表明:1)婴儿的共同注意力在8~11个月间逐步提高,9个月左右出现显著的发展性变化,但1岁以前,该能力的发展水平都较低;2)就共同注意而言,婴儿具有从练习经验中学习的可能性,且学习能力存在年龄差异,8个月的婴儿基本不能从练习中受益,而8个月以上的其他三组婴儿在练习后共同注意水平都有不同程度的提高;3)总体而言,女婴共同注意能力的发展水平显著地高于男婴。 相似文献