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961.
Uneconomical choices by humans or animals that evaluate reward options challenge the expectation that decision-makers always
maximize the return currency. One possible explanation for such deviations from optimality is that the ability to sense differences
in physical value between available alternatives is constrained by the sensory and cognitive processes for encoding profitability.
In this study, we investigated the capacity of a nectarivorous bat species (Glossophaga commissarisi) to discriminate between sugar solutions with different concentrations. We conducted a two-alternative free-choice experiment
on a population of wild electronically tagged bats foraging at an array of computer-automated artificial flowers that recorded
individual choices. We used a Bayesian approach to fit individual psychometric functions, relating the strength of preferring
the higher concentration option to the intensity of the presented stimulus. Psychometric analysis revealed that discrimination
ability increases non-linearly with respect to intensity. We combined this result with a previous psychometric analysis of
volume perception. Our theoretical analysis of choice for rewards that vary in two quality dimensions revealed regions of
parameter combinations where uneconomic choice is expected. Discrimination ability may be constrained by non-linear perceptual
and cognitive encoding processes that result in uneconomical choice. 相似文献
962.
The ability to discriminate between quantities has been observed in many species. Typically, when an animal is given a choice between two sets of food, accurate performance (i.e., choosing the larger amount) decreases as the ratio between two quantities increases. A recent study reported that elephants did not exhibit ratio effects, suggesting that elephants may process quantitative information in a qualitatively different way from all other nonhuman species that have been tested (Irie-Sugimoto et al. in Anim Cogn 12:193-199, 2009). However, the results of this study were confounded by several methodological issues. We tested two African elephants (Loxodonta africana) to more thoroughly investigate relative quantity judgment in this species. In contrast to the previous study, we found evidence of ratio effects for visible and nonvisible sequentially presented sets of food. Thus, elephants appear to represent and compare quantities in much the same way as other species, including humans when they are prevented from counting. Performance supports an accumulator model in which quantities are represented as analog magnitudes. Furthermore, we found no effect of absolute magnitude on performance, providing support against an object-file model explanation of quantity judgment. 相似文献
963.
The goal of three experiments was to study whether rats are aware of the difference between absence of events and lack of evidence. We used a Pavlovian extinction paradigm in which lights consistently signaling sucrose were suddenly paired with the absence of sucrose. The crucial manipulation involved the absent outcomes in the extinction phase. Whereas in the Cover conditions, access to the drinking receptacle was blocked by a metal plate, in the No Cover conditions, the drinking receptacle was accessible. The Test phase showed that in the Cover conditions, the measured expectancies of sucrose were clearly at a higher level than in the No Cover conditions. We compare two competing theories potentially explaining the findings. A cognitive theory interprets the observed effect as evidence that the rats were able to understand that the cover blocked informational access to the outcome information, and therefore the changed learning input did not necessarily signify a change of the underlying contingency in the world. An alternative associationist account, renewal theory, might instead explain the relative sparing of extinction in the Cover condition as a consequence of context change. We discuss the merits of both theories as accounts of our data and conclude that the cognitive explanation is in this case preferred. 相似文献
964.
Different event-related potentials (ERPs) have been shown to correlate with learning from feedback in decision-making tasks
and with learning in explicit memory tasks. In the present study, we investigated which ERPs predict learning from corrective
feedback in a multiple-choice test, which combines elements from both paradigms. Participants worked through sets of multiple-choice
items of a Swahili–German vocabulary task. Whereas the initial presentation of an item required the participants to guess
the answer, corrective feedback could be used to learn the correct response. Initial analyses revealed that corrective feedback
elicited components related to reinforcement learning (FRN), as well as to explicit memory processing (P300) and attention
(early frontal positivity). However, only the P300 and early frontal positivity were positively correlated with successful
learning from corrective feedback, whereas the FRN was even larger when learning failed. These results suggest that learning
from corrective feedback crucially relies on explicit memory processing and attentional orienting to corrective feedback,
rather than on reinforcement learning. 相似文献
965.
Cooper NR Puzzo I Pawley AD Bowes-Mulligan RA Kirkpatrick EV Antoniou PA Kennett S 《Cognitive, affective & behavioral neuroscience》2012,12(2):393-405
Ongoing debate in the literature concerns whether there is a link between contagious yawning and the human mirror neuron system
(hMNS). One way of examining this issue is with the use of the electroencephalogram (EEG) to measure changes in mu activation
during the observation of yawns. Mu oscillations are seen in the alpha bandwidth of the EEG (8–12 Hz) over sensorimotor areas.
Previous work has shown that mu suppression is a useful index of hMNS activation and is sensitive to individual differences
in empathy. In two experiments, we presented participants with videos of either people yawning or control stimuli. We found
greater mu suppression for yawns than for controls over right motor and premotor areas, particularly for those scoring higher
on traits of empathy. In a third experiment, auditory recordings of yawns were compared against electronically scrambled versions
of the same yawns. We observed greater mu suppression for yawns than for the controls over right lateral premotor areas. Again,
these findings were driven by those scoring highly on empathy. The results from these experiments support the notion that
the hMNS is involved in contagious yawning, emphasise the link between contagious yawning and empathy, and stress the importance
of good control stimuli. 相似文献
966.
Ravizza SM Goudreau J Delgado MR Ruiz S 《Cognitive, affective & behavioral neuroscience》2012,12(1):193-206
Disruption of the dorsal frontostriatal pathways in Parkinson’s disease (PD) is associated with impairments in motivation,
as well as in executive function. The goal of this study was to investigate whether these impairments are related and, if
so, whether the disruption of frontostriatal pathways compromises the ability to process the motivational aspects of feedback
in such tasks. In Experiment 1, informative feedback improved the performance of young, healthy participants in a task-switching paradigm. This task-switching
paradigm was then used in Experiment 2 to test whether feedback would improve the performance of 17 PD patients and age-matched controls. The PD group benefitted
from feedback to the same degree as control participants; however, depression scores on the Beck Depression Inventory were
significantly related to feedback usage, especially when response selection demands were high. Regardless of feedback, PD
patients were more impaired when response demands were high than in an equally difficult condition with low action demands.
These results suggest that response selection is a core impairment of insufficient dopamine to the dorsal frontal striatal
pathways. 相似文献
967.
Although the amount or scale of biographical knowledge held in store about a person may differ widely, little is known about
whether and how these differences may affect the retrieval processes triggered by the person’s face. In a learning paradigm,
we manipulated the scale of biographical knowledge while controlling for a common set of minimal knowledge and perceptual
experience with the faces. A few days after learning, and again after 6 months, knowledge effects were assessed in three tasks,
none of which concerned the additional knowledge. Whereas the performance effects of additional knowledge were small, event-related
brain potentials recorded during testing showed amplitude modulations in the time range of the N400 component—indicative of
knowledge access—but also at a much earlier latency in the P100 component—reflecting early stages of visual analysis. However,
no effects were found in the N170 component, which is taken to reflect structural analyses of faces. The present findings
replicate knowledge scale effects in object recognition and suggest that enhanced knowledge affects both early visual processes
and the later processes associated with semantic processing, even when this knowledge is not task-relevant. 相似文献
968.
This study examined how self-relevant failure influences error monitoring—as reflected in the error-related negativity (Ne/ERN)
—and behavioral adaptation during subsequent feedback-based learning. We applied two phases (pre- and posttest) of a probabilistic
learning task. Between pre- and posttest, participants were assigned to one of two groups receiving either failure feedback
or no feedback during a visual search task described as diagnostic of intellectual abilities. To disentangle the effects of
failure and motivational disengagement due to prolonged task performance, we linked the posttest to intelligence (Experiment
1) or described it in neutral terms (Experiment 2). Failure induction was associated with an increase in Ne/ERN amplitude at posttest in both experiments, although there were
no differences in overall performance. In contrast, the Ne/ERN decreased from pre- to posttest in the no-failure-feedback
group, particularly in Experiment 2. Furthermore, failure feedback affected error-related behavioral adjustments, suggesting a shift toward a reactive, error-driven
mode of behavior control. These findings emphasize the importance of affective-motivational state in error processing and
subsequent behavioral adaptation. 相似文献
969.
Research on children's emotional competence has received considerable attention in the last decade, including the role of language. Language competence (LC) and emotional competence (EC) comprise multiple components. These components and their specific interrelations have not been studied sufficiently. In our study, we examined relations between multiple components of LC and EC in a sample of 210 school-age children. Five measures represented LC: receptive vocabulary, verbal fluency, literacy, narrative structure, and the narrative use of evaluative devices. Four measures represented EC: expressive emotion vocabulary, declarative emotion knowledge, awareness of mixed emotions, and facial emotion recognition. Results showed strong positive correlations between LC and EC ranging between r = .12 and r = .45. In particular, receptive vocabulary and literacy were closely related to emotion knowledge and awareness of mixed emotions. A confirmatory factor analysis revealed that there is a common general ability factor for LC and EC. We discuss why receptive vocabulary and literacy might be so strongly related to emotion knowledge in school-age children. Our findings have implications for developmental psychologists, educational research, and speech-language pathologists. 相似文献
970.
The present study addressed the hypothesis that emotional stimuli relevant to survival or reproduction (biologically emotional
stimuli) automatically affect cognitive processing (e.g., attention, memory), while those relevant to social life (socially
emotional stimuli) require elaborative processing to modulate attention and memory. Results of our behavioral studies showed
that (1) biologically emotional images hold attention more strongly than do socially emotional images, (2) memory for biologically
emotional images was enhanced even with limited cognitive resources, but (3) memory for socially emotional images was enhanced
only when people had sufficient cognitive resources at encoding. Neither images’ subjective arousal nor their valence modulated
these patterns. A subsequent functional magnetic resonance imaging study revealed that biologically emotional images induced
stronger activity in the visual cortex and greater functional connectivity between the amygdala and visual cortex than did
socially emotional images. These results suggest that the interconnection between the amygdala and visual cortex supports
enhanced attention allocation to biological stimuli. In contrast, socially emotional images evoked greater activity in the
medial prefrontal cortex (MPFC) and yielded stronger functional connectivity between the amygdala and MPFC than did biological
images. Thus, it appears that emotional processing of social stimuli involves elaborative processing requiring frontal lobe
activity. 相似文献