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251.
Between 1998 and 2006, twenty-seven states amended their constitutions to prohibit same sex marriage. The 2008 elections again
saw three states with ballot measures aimed at banning gay marriage. This study examines the determinants of support for those
measures in California and Florida, and includes a similar measure placed on the primary election ballot in California in
2000. Support is measured as the county-wide vote in favor of each gay marriage ban. A number of hypotheses are explored that
examine the urban/rural nature of each county, as well as the political and demographic characteristics of county residents.
It is suggested that states may be best viewed as relatively independent groupings of diverse subcultures, rather than as
homogenous populations with a single political culture. The findings reported here indicate that a host of demographic, political
and religious differences within each state influence residents’ votes on gay marriage bans. 相似文献
252.
253.
The Bengalese finch (Lonchura striata var. domestica) is a species of songbird. Males sing courtship songs with complex note-to-note transition rules, while females discriminate
these songs when choosing their mate. The present study uses serial reaction time (RT) to examine the characteristics of the
Bengalese finches’ sequential behaviours beyond song production. The birds were trained to produce the sequence with an “A–B–A”
structure. After the RT to each key position was determined to be stable, we tested the acquisition of the trained sequential
response by presenting novel and random three-term sequences (random test). We also examined whether they could abstract the
embedded rule in the trained sequence and apply it to the novel test sequence (abstract test). Additionally, we examined rule
abstraction through example training by increasing the number of examples in baseline training from 1 to 5. When considered
as (gender) groups, training with 5 examples resulted in no statistically significant differences in the abstract tests, while
statistically significant differences were observed in the random tests, suggesting that the male birds learned the trained
sequences and transferred the abstract structure they had learned during the training trials. Individual data indicated that
males, as opposed to females, were likely to learn the motor pattern of the sequence. The results are consistent with observations
that males learn to produce songs with complex sequential rules, whereas females do not. 相似文献
254.
Non-human primates possess species-specific repertoires of acoustically distinct call types that can be found in adults in
predictable ways. Evidence for vocal flexibility is generally rare and typically restricted to acoustic variants within the
main call types or sequential production of multiple calls. So far, evidence for context-specific call sequences has been
mainly in relation to external disturbances, particularly predation. In this study, we investigated extensively the vocal
behaviour of free-ranging and individually identified Diana monkeys in non-predatory contexts. We found that adult females
produced four vocal structures alone (‘H’, ‘L’, ‘R’ and ‘A’ calls, the latter consisting of two subtypes) or combined in non-random
ways (‘HA’, ‘LA’ and ‘RA’ call combinations) in relation to ongoing behaviour or external events. Specifically, the concatenation
of an introductory call with the most frequently emitted and contextually neutral ‘A’ call seems to function as a contextual
refiner of this potential individual identifier. Our results demonstrate that some non-human primates are able to increase
the effective size of their small vocal repertoire not only by varying the acoustic structure of basic call types but also
by combining them into more complex structures. We have demonstrated this phenomenon for a category of vocalisations with
a purely social function and discuss the implications of these findings for evolutionary theories of primate vocal communication. 相似文献
255.
Although rats are able to build complex spatial representations of their surroundings during exploration, the nature of the
encoded information is still a matter for debate. In particular, it is not well established if rats can process the topological
structure of the environment in such a way that they are aware of the connections existing between remote places. Here, rats
were first exposed for four 5-min trials to a complex environment divided into several sectors that were separated by doors
allowing either unrestricted or restricted access to other sectors. In the fifth test trial, we measured the behavior of the
animals while they explored the same environment in which, however, they faced changes that either altered or did not alter
the topological structure of the environment. In experiment 1, closing previously opened doors prevented the rat from having
direct access between corresponding sectors. In experiment 2, opening previously closed doors allowed direct access between
sectors that had not been directly accessible. In each experiment, control doors allowed us to discard the mere influence
of door manipulation. We compared the rats’ exploratory behavior in response to door manipulations that either strongly altered
or did not alter the ability to commute between sectors and found evidence that the animals displayed differential reactions
to the two types of door manipulations. This implies that during exploration rats build a precise map of the connectivity
of space that can be flexibly updated and used for efficient navigation. 相似文献
256.
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
257.
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
258.
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
259.
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
260.
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