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991.
To investigate the perceptual mechanisms underlying conspecific vocal recognition in canine species, eighteen dogs were presented with playbacks of normal and reversed versions of typical dog vocalizations. Auditory perception was analysed using the head-turn paradigm, a non-invasive technique extensively employed to study hemispheric specializations for processing conspecific vocalizations in primates. The results revealed that dogs usually turn their heads with the right ear leading (left hemisphere activation) in response to the forward version of their typical calls, and with either no bias and the left ear leading (right hemisphere activation) in response to the reversed call versions. Overall, our findings suggest that temporal features are determinant auditory cues for call sound recognition in dogs, and support earlier findings of the role of the left hemisphere in the analyses of intraspecific communication. 相似文献
992.
A hallmark of higher cognition is the flexible use of information. This requires an abstract representation of the information. In sequence learning, ordinal position knowledge is seen as a more versatile representation when compared to chaining. Here, we assessed which of these mental representations is the most natural and most dominant in jackdaws. Two jackdaws (Corvus monedula) were trained on 14 separate three-item sequences (triplets), made up of abstract images. On each trial, the three items of one triplet were presented in fixed order. The images represented either the first, second or third ordinal position. Test stimuli consisted of the three images and a distractor image that was chosen randomly from the remaining sequences. We rewarded pecking in the correct order to the images belonging to the same sequence. The most common error the birds made was to peck at a distractor item from the same ordinal position. To look at how versatile the jackdaws' ordinal knowledge was, we replaced a familiar item with a novel item in some sequences. We then created novel sequences with these items, which the birds completed correctly. It appears, then, that jackdaws have a concept of ordinal position. 相似文献
993.
994.
A new method is proposed for controlling mosquito-borne diseases. In particular, instead of trying to kill mosquitoes, we suggest provisioning them with food from artificial feeders. Because mosquito populations are frequently limited by ecological factors other than blood meals, such as the availability of egg-laying sites, feeding mosquitoes would not necessarily increase the total number of mosquitoes, but could reduce the number of human-drawn mosquito meals. Like mosquito traps, feeders could divert biting mosquitoes away from people by means of lures, but, after diversion, prevent subsequent human bites by satiating the mosquitoes instead of killing them. Mosquito feeders might reduce the problem of the evolution of resistance to control: in an ecology with mosquito feeders, which provide safe and abundant calories for adult female mosquitoes, there could be selection for preferring (rather than avoiding) feeders, which could eventually lead to a population of feeder-preferring mosquitoes. Artificial feeders also offer the chance to introduce novel elements into the mosquito diet, such as anti- malarial or other anti-parasitic agents. Feeders might directly reduce human bites and harnesses the power of natural selection by selectively favoring feeder-preferring (rather than trap-resistant) mosquitoes. 相似文献
995.
Humans (Homo sapiens) and chimpanzees (Pan troglodytes) can extract socially-relevant information from the static, non-expressive faces of conspecifics. In humans, the face is a valid signal of both personality and health. Recent evidence shows that, like humans, chimpanzee faces also contain personality information, and that humans can accurately judge aspects of chimpanzee personality relating to extraversion from the face alone (Kramer, King, and Ward, 2011). These findings suggest the hypothesis that humans and chimpanzees share a system of personality and facial morphology for signaling socially-relevant traits from the face. We sought to test this hypothesis using a new group of chimpanzees. In two studies, we found that chimpanzee faces contained health information, as well as information of characteristics relating to extraversion, emotional stability, and agreeableness, using average judgments from pairs of individual photographs. In a third study, information relating to extraversion and health was also present in composite images of individual chimpanzees. We therefore replicate and extend previous findings using a new group of chimpanzees and demonstrate two methods for minimizing the variability associated with individual photographs. Our findings support the hypothesis that chimpanzees and humans share a personality signaling system. 相似文献
996.
The inferior frontal gyrus/anterior insula (IFG/AI) and anterior cingulate cortex (ACC) are key regions involved in risk appraisal during decision making, but accounts of how these regions contribute to decision making under risk remain contested. To help clarify the roles of these and other related regions, we used a modified version of the Balloon Analogue Risk Task (Lejuez et al., Journal of Experimental Psychology: Applied, 8, 75-84, 2002) to distinguish between decision-making and feedback-related processes when participants decided to pursue a gain as the probability of loss increased parametrically. Specifically, we set out to test whether the ACC and IFG/AI regions correspond to loss aversion at the time of decision making in a way that is not confounded with either reward-seeking or infrequency effects. When participants chose to discontinue inflating the balloon (win option), we observed greater ACC and mainly bilateral IFG/AI activity at the time of decision as the probability of explosion increased, consistent with increased loss aversion but inconsistent with an infrequency effect. In contrast, we found robust vmPFC activity when participants chose to continue inflating the balloon (risky option), consistent with reward seeking. However, in the cingulate and in mainly bilateral IFG regions, blood-oxygenation-level-dependent activation decreased when participants chose to inflate the balloon as the probability of explosion increased, findings that are consistent with a reduced loss aversion signal. Our results highlight the existence of distinct reward-seeking and loss-averse signals during decision making, as well as the importance of distinguishing between decision and feedback signals. 相似文献
997.
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
998.
Drebing CE Mueller L Van Ormer EA Duffy P LePage J Rosenheck R Drake R Rose GS King K Penk W 《Psychological services》2012,9(1):49-63
The current study provides naturalistic data documenting the pathways-to-care to vocational services for 155 veterans who were receiving some form of mental health care from the Veterans Health Administration and had a vocational need but were not currently enrolled in vocational services. Of the participants, 94.2% had recognized their vocational need, 80.6% reported that they or someone else had sought help to alleviate the need, and 77.4% had previously received some form of vocational services. The median length of the participants' vocational need was more than 4.2 years. Delays associated with recognition, help-seeking, and treatment entry all contributed to the overall delay in entering appropriate care. Filtering factors associated with quicker recognition, seeking help, and receiving services included diagnosis, level of disability, type of vocational need, and support from primary providers, family, and friends. The results provide information for designing interventions to improve service entry by adults with mental health problems and vocational needs. 相似文献
999.
Garland AF Haine-Schlagel R Accurso EC Baker-Ericzén MJ Brookman-Frazee L 《Psychological services》2012,9(1):74-88
Sustained treatment attendance has been reported to be poor in publicly funded community-based clinic settings serving children and families. Several child and family characteristics have been shown to predict attendance in community-based care, but virtually no research has been conducted to examine how experiences in care, including psychotherapists' within-session practices, influence client attendance. The goal of this exploratory study was to examine how observed practice within sessions, in particular the extent to which therapists delivered elements consistent with evidence-based practices, impacts total number of sessions attended, while accounting for an array of other potential predictors. Participants include 181 children ages 4-13 and their parents entering a new episode of care for disruptive behavior problems in publicly funded clinics. Data sources include administrative billing records on treatment attendance; coded videotaped treatment sessions; and self-reports from children, parents, and therapists. Results indicate that parent education, service funding source, parent alliance with therapist, and therapist experience predicted number of sessions attended; intensity of evidence-based treatment techniques delivered to children was marginally associated with attendance (p = .059). Implications for improving engagement in community-based care are discussed. 相似文献
1000.
Regardless of age, education, or social status, we all experience moments where we ask ourselves, "what was I thinking?!?" Typically, we experience errors of this sort, or slips of action, during routine tasks that require a whole sequence of movements. However, most action slip research has focused on creating response conflict within single movements. The Slip Induction Task (SIT) is a step toward creating response conflict within truer to life action routines. As such, the SIT attempts to induce action slips in a well-learned movement routine through the occasional presentation of unexpected cues. We find that the SIT is able to reliably induce action slips, especially when the unexpected cue necessitates a movement to an unexpected target location. Furthermore, when participants are able to avoid an action slip, these changes in movement routine are accompanied by a cost in speed. 相似文献