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181.
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
182.
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
183.
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
184.
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
185.
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
186.
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
187.
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
188.
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
189.
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
190.
Though previous research suggests that attendance at individual therapy is not impacted by amount or source of payment for services, such research is relatively sparse and clinician concerns remain. The present study explores the connection between payment of fees and attendance at group treatments--a previously unexplored area. Participants in a 10-week behavioral parent training (BPT) program varied in timing of payment of fees as well as amount of fees based on income. The varying payment schedules did not affect attendance to sessions at which payments were due nor did payment schedules affect completion of the program. A small relationship was found between income group and attendance. The results are discussed in their relation to the larger literature on fees and attendance at psychotherapy. 相似文献