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1.
This paper describes preference classes and preference Moore machines as a basis for integrating different hybrid neural representations. Preference classes are shown to provide a basic link between neural preferences and fuzzy representations at the preference class level. Preference Moore machines provide a link between recurrent neural networks and symbolic transducers at the preference Moore machine level. We demonstrate how the concepts of preference classes and preference Moore machines can be used to interpret neural network representations and to integrate knowledge from hybrid neural representations. One main contribution of this paper is the introduction and analysis of neural preference Moore machines and their link to a fuzzy interpretation. Furthermore, we illustrate the interpretation and combination of various neural preference Moore machines with additional real-world examples.  相似文献   

2.
Preferences in pigeons for free choice over forced choice under uncertain contingencies were compared with the one under certain contingencies in multiple concurrent-chain schedules of reinforcement. The uncertain condition examined the preference for two alternatives over one alternative when reinforcement probability at the end of the terminal link equalled 0.5, and with all keys in each terminal link lit green (two mixed fixed-interval extinction keys versus one mixed fixed-interval extinction key). Key and schedule arrangement in the certain condition was the same except that a peck on any terminal-link key after the FI interval always produced food. When naive pigeons were first exposed to uncertain contingencies, preference for two lit keys over one lit key was observed, and the preference was confirmed by sequential reversals of the terminal-link contingencies. However, no consistent preference was observed when uncertain condition followed the certain condition. Under certain contingencies, unlike the earlier experiments, very small and inconsistent preferences for free choice were demonstrated. A possible reason for the different preferences in the uncertain conditions was that pigeons may lessen their sensitivity to the circumstances with uncertainty by any history or carry-over effect of the prior contingency.  相似文献   

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This paper investigates hypotheses drawn from two sources: (1) Belsky, Steinberg, and Draper’s (1991) attachment theory model of the development of reproductive strategies, and (2) recent life history models and comparative data suggesting that environmental risk and uncertainty may be potent determinants of the optimal tradeoff between current and future reproduction. A retrospective, self-report study of 136 American university women aged 19–25 showed that current recollections of early stress (environmental risk and uncertainty) were related to individual differences in adult time preference and adult sexual behavior, and that individual differences in time preference were related to adult attachment organization and sexual behavior. These results are consistent with the hypothesis that perceptions of early stress index environmental risk and uncertainty and mediate the attachment process and the development of reproductive strategies. On this view individual differences in time preference are considered to be part of the attachment theoretical construct of an internal working model, which itself is conceived as an evolved algorithm for the contingent development of alternative reproductive strategies.  相似文献   

7.
When confronted with a novel situation rats show a tendency either to stay in a dark place or to retreat to a familiar place, if available. To produce a conflict between these two tendencies the rat's home cage was connected by a runway to a dark but unfamiliar compartment. Three groups of rats were tested in this apparatus with different levels of illumination in the home cage. Tryon Maze Bright rats showed a strong preference for the home cage which was independent of the illumination level. This preference was also found in Wistar rats. With a very high level of illumination in the home cage, however, Wistar rats showed a preference for the home cage only in the first few trials or a series of repeated trials. In later trials they spent more time in the dark part of the apparatus. The results were regarded as an indication that in a novel situation rats primarily search for a familiar place. When such a place is available they tolerate aversive stimulation present in this place.  相似文献   

8.
Drugs of abuse, such as phencyclidine (PCP), methamphetamine (METH), and cocaine (COC) are known to affect several behaviors in rats, such as motor activity, stereotypy, and circling. In this study, we evaluated whether these drugs produce circling preferences in the presence or absence of unilateral 6-hydroxydopamine (6-OHDA)-induced lesions of the caudate nucleus. Adult male CD rats were lesioned with 10 μg 6-OHDA/site. Animals were dosed with PCP (15 mg/kg, ip), its congener, (+) MK-801 (0.15 mg/kg, ip), METH (2 mg/kg, ip), COC (60 mg/kg, ip), or apomorphine (0.2 mg/kg, ip). circling preference was recorded in control and lesioned rats for 2 h before animals were sacrificed to determine monoamine levels by HPLC/EC. In control animals, administration of these drugs produced 60–70% left circling. In, lesioned animals, these drugs produced 78–90% ipsilateral (toward the lesion) circling, except apomorphine, which produced 60–80% contralateral (away from the lesion) circling. Dopamine (DA) and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) concentrations significantly decreased ipsilaterally in lesioned caudate nucleus (CN) and substantia nigra (SN). However, no significant changes were observed in nucleus accumbens (NA) and olfactory tubercles (OT). These data demonstrate that drugs of abuse like PCP, its congener (+) MK-801, METH, and COC produce a greater preference to turn toward the left than the right, a finding similar to that found in human psychosis. Since 6-OHDA lesions enhanced the circling bias and depleted DA and its metabolites DOPAC and HVA, it also suggests that the dopaminergic system may be involved in the circling behavior.  相似文献   

9.
Young mammals come to approach the odor of their mother, a response that facilitates their survival during early life. Young rats induce a cascade of events in their mother to induce the emission of her odor. The pups increase circulating prolactin levels, which increases food intake and the emission of large quantities of cecotrophe containing the maternal odor. This odor is synthesized by the action of cecal microorganisms and changes with maternal diet. The diet-dependence of the odor requires the pups to acquire their attraction to the odor postnatally. The acquisition of this preference occurs when an odor is paired with the tactile stimulation that pups receive during maternal care. The action of the tactile stimulation appears to be mediated by noradrenaline. The development of this type of olfactory attraction is accompanied by changes in the regions of the olfactory bulb that are responsive to the attractive odor. Metabolic, anatomical, and neurophysiological changes in response to the attractive odor emerge in such regions of the bulb after early olfactory preference training. © 1992 John Wiley & Sons, Inc.  相似文献   

10.
How social aggregations arise and persist is central to our understanding of evolution, behavior, and psychology. When social groups arise within a species, evolutionary divergence and speciation can result. To understand this diversifying role of social behavior, we must examine the internal and external influences that lead to nonrandom assortment of phenotypes. Many fishes form aggregations called shoals that reduce predation risk while enhancing foraging and reproductive success. Thus, shoaling is adaptive, and signals that maintain shoals are likely to evolve under selection. Given the diversity of pigment patterns among Danio fishes, visual signals might be especially important in mediating social behaviors in this group. Our understanding of pigment pattern development in the zebrafish D. rerio allows integrative analyses of how molecular variation leads to morphological variation among individuals and how morphological variation influences social interactions. Here, we use the zebrafish pigment mutant nacre/mitfa to test roles for genetic and environmental determinants in the development of shoaling preference. We demonstrate that individuals discriminate between shoals having different pigment pattern phenotypes and that early experience determines shoaling preference. These results suggest a role for social learning in pigment pattern diversification in danios.  相似文献   

11.
Feeding preferences of xylophagous termites have been determined by comparing differences in wood biomass removed, percentage of wood consumed or degree of damage rated in arbitrary categories. When test woods differ in physical characteristics such as density, these measures are not comparable. We examined the response of the Formosan termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) to wood that differed in physical characteristics by compressing blocks to 40% greater than the natural density. Termites ate significantly greater percentages, but similar amounts of biomass, of uncompressed over compressed natural pine. In contrast, they ate significantly greater amounts of biomass, but similar percentages, of compressed over uncompressed mahogany. Whether percentage or amount of biomass removed should be used as a measure of preference depends on what regulates insect meal size. If termites consume meals of fixed biomass, then biomass consumed is the correct measure; percentage removed is appropriate if they consume meals of fixed volume.Deceased, July 25, 1989  相似文献   

12.
Minority type human mate preference   总被引:1,自引:0,他引:1  
T H Thelen 《Social biology》1983,30(2):162-180
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Godbey T  Gray G  Jeffery D 《Lab animal》2011,40(7):225-230
Before animal research facilities began using individually ventilated cage (IVC) systems for mice, cages were often changed one or more times per week. When using IVC systems, however, it is standard practice to change cages only once every 2-3 weeks. When deciding how often to change cages, personnel may consider the cost of labor needed to change the cage, as well as the cage type and bedding type, rather than animal preference or concern for animal well-being. The authors carried out a simple preference test in groups of mice. Mice were allowed to choose between an unsoiled cage and cages that had not been changed for 1 d, 7 d or 14 d. When evaluating where mice positioned their nests and the amount of time mice spent in the various cages, the authors found that the mice preferred the unsoiled cage. Younger mice (<150 d old) showed a stronger preference for the unsoiled cage than did older mice (>150 d old). Further studies are warranted to evaluate mice's preferences for cages changed at different intervals and to determine whether prolonging the interval between cage changes has any negative effects on mice.  相似文献   

15.
双斑长跗萤叶甲的嗜食性   总被引:4,自引:0,他引:4  
双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)是一种多食性害虫。目前该虫害已成为新疆北部大部分棉区一种新的主要害虫。通过非选择性实验研究双斑长跗萤叶甲在新疆北疆的取食范围,结果表明:在25科54属58种植物中,该虫喜食植物有25种,较喜食植物有21种,完全不取食的有12种。  相似文献   

16.
L C Wang  T F Lee 《Life sciences》1985,36(26):2539-2546
The present study investigated the suitability of different substrates on aminophylline (AMPY)-induced thermogenesis in rats during cold exposure. Feeding of distilled water 60 min prior to cold exposure in two-day fasted rats resulted in the lowest total heat production and final body temperature in both saline- and AMPY-treated groups. Feeding of 5 ml Intralipid (2 Kcal/ml), a triglyceride mixture, did not improve thermogenesis beyond the control levels. However, feeding of isocaloric substitutes of sucrose elevated significantly the total thermogenesis by 7.9% and 7.4% and final body temperature by 2.23 and 1.61 degrees C, respectively, in saline- and AMPY-treated groups. The increase in thermogenesis by sucrose is not due to its thermic effect. It is concluded that sucrose, in combination with AMPY, may be of value in improving resistance to cold.  相似文献   

17.
The present study aimed to explore for the first time the relationship between circadian preference and different decision-making styles. In total, 501 young adults (330 females), with a mean age of 21.07 ± 1.99 years, took part in the study. The participants completed the reduced version of the morningness–eveningness questionnaire (rMEQ) and the general decision-making style inventory (GDMS). The rMEQ enabled to assess the circadian preference, with lower rMEQ scores pointing toward eveningness preference. The GDMS measured five decision-making styles: rational, intuitive, dependent, avoidant and spontaneous. Higher scores on each GDMS decision-making style reflect a higher prevalence of the corresponding style. A set of multiple regression analyses was performed with rMEQ score, gender and age as predictors together with each GDMS decision-making style as dependent variable. rMEQ score proved to be the only significant (negative) predictor of avoidant and spontaneous decision-making styles, i.e. lower rMEQ score (tendency toward eveningness) significantly predicted higher score at these decision-making styles. The present results suggest that eveningness preference is significantly related to avoidant and spontaneous decision-making styles in young adults. Such results will be discussed with reference to the effects of decision-making styles on decision-making in different types of workers and mental health.  相似文献   

18.
Taste aversion and frugivore preference   总被引:2,自引:0,他引:2  
Anne E. Sorensen 《Oecologia》1983,56(1):117-120
Summary I tested the hypothesis that thrushes avoid certain species of fruits because of their taste. It was found that thrushes had significant preferences and aversions for the flavours of certain species of fruit. Several species of fruit which thrushes avoided contained identified toxins. It is speculated that some species of plants have evolved fruit toxins to prevent thrushes from consuming fruits and dispersing seeds to unfavourable habitats.  相似文献   

19.
Sperm preference in Drosophila melanogaster   总被引:2,自引:2,他引:0       下载免费PDF全文
D Childress  D L Hartl 《Genetics》1972,71(3):417-427
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20.
Sexual selection is responsible for many of the most spectacular displays in nature, and female preference for certain males is central to much of this. However, female preference is relatively poorly understood, particularly the relative importance of a female's genes, the environment and their interaction on her preference. We investigated preference in a no-choice design using Drosophila melanogaster iso-female lines and find that there are genotype-by-environment interactions for female preference. Whereas the choosiness of some female genotypes differed little across environments, that of others differed greatly, so that the choosiness rank of females in one environment did not necessarily predict their rank in another. Furthermore, the genetic variance underlying preference also varied across environments. These findings have important consequences for the evolution of female preference and the male sexual traits preference targets.  相似文献   

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