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991.
Investigations using invertebrate species have led to a considerable progress in our understanding of the mechanisms underlying learning and memory. In this review we describe the main behavioral and neuronal findings obtained by studying the habituation of the escape response to a visual danger stimulus in the crab Chasmagnathus granulatus. Massed training with brief intertrial intervals lead to a rapid reduction of the escape response that recovers after a short term. Conversely, few trials of spaced training renders a slower escape reduction that endures for many days. As predicted by Wagner’s associative theory of habituation, long-term habituation in the crab proved to be determined by an association between the contextual environment of the training and the unconditioned stimulus. By performing intracellular recordings in the brain of the intact animal at the same time it was learning, we identified a group of neurons that remarkably reflects the short- and long-term behavioral changes. Thus, the visual memory abilities of crabs, their relatively simple and accessible nervous system, and the recording stability that can be achieved with their neurons provide an opportunity for uncovering neurophysiological and molecular events that occur in identifiable neurons during learning.  相似文献   
992.
The quality of youth violence prevention practice is dependent on the quality of education and training of professionals who will care for disadvantaged and/or underserved youth. The authors propose that culturally responsive youth violence prevention curricula, focused on Asian Americans and Pacific Islanders, should: 1) target institutions that train health professionals likely to serve Asian Americans and Pacific Islanders; 2) promote the professional development of Asian American and Pacific Islander students and enhance all students' comfort in addressing behavioral, social, and cultural concerns; 3) cover specific issues relevant to Asian Americans and Pacific Islanders, including the role of acculturative stress, socioeconomic hardship, and other risk factors that may account for mental health disparities; and 4) continuously engage researchers, educators, and community stakeholders in cooperatively and creatively applying new knowledge to clinical challenges. The authors summarize resources for youth violence prevention education that have been used for training healthcare professionals in a multicultural context.  相似文献   
993.
During the first year of life, infants begin to have difficulties perceiving non‐native vowel and consonant contrasts, thus adapting their perception to the phonetic categories of the target language. In this paper, we examine the perception of a non‐segmental feature, i.e. stress. Previous research with adults has shown that speakers of French (a language with fixed stress) have great difficulties in perceiving stress contrasts ( Dupoux, Pallier, Sebastián & Mehler, 1997 ), whereas speakers of Spanish (a language with lexically contrastive stress) perceive these contrasts as accurately as segmental contrasts. We show that language‐specific differences in the perception of stress likewise arise during the first year of life. Specifically, 9‐month‐old Spanish infants successfully distinguish between stress‐initial and stress‐final pseudo‐words, while French infants of this age show no sign of discrimination. In a second experiment using multiple tokens of a single pseudo‐word, French infants of the same age successfully discriminate between the two stress patterns, showing that they are able to perceive the acoustic correlates of stress. Their failure to discriminate stress patterns in the first experiment thus reflects an inability to process stress at an abstract, phonological level.  相似文献   
994.
Despite a widespread familiarity with the often compelling urge to yawn after perceiving someone else yawn, an understanding of the neural mechanism underlying contagious yawning remains incomplete. In the present auditory fMRI study, listeners used a 4-point scale to indicate how much they felt like yawning following the presentation of a yawn, breath, or scrambled yawn sound. Not only were yawn sounds given significantly higher ratings, a trait positively correlated with each individual’s empathy measure, but relative to control stimuli, random effects analyses revealed enhanced hemodynamic activity in the right posterior inferior frontal gyrus (pIFG) in response to hearing yawns. Moreover, pIFG activity was greatest for yawn stimuli associated with high as opposed to low yawn ratings and for control sounds associated with equally high yawn ratings. These results support a relationship between contagious yawning and empathy and provide evidence for pIFG involvement in contagious yawning. A supplemental figure for this study may be downloaded from http://cabn.psychonomic-journals.org/content/supplemental.  相似文献   
995.
The role of conscious cognitive processes in human affective conditioning remains controversial, with several theories arguing that such conditioning can occur without awareness of the conditioned stimulus (CS)-unconditioned stimulus (UCS) contingency. One specific type of affective conditioning in which unaware conditioning is said to occur is "evaluative conditioning." The present experiment tested the role of contingency awareness by embedding an evaluative conditioning paradigm in a distracting masking task while obtaining, in addition to subjective ratings of affect, both psychophysiological (skin conductance and startle eyeblink) and indirect behavioral (affective priming) measures of conditioning, along with a trial-by-trial measure of awareness from 55 college student participants. Aware participants showed conditioning with all of the measures; unaware participants failed to show conditioning with all measures. The behavioral, neurophysiological, and therapeutic implications of these findings are discussed.  相似文献   
996.
This article presents the Spanish adaptation of the Affective Norms for English Words (ANEW; Bradley & Lang, 1999). The norms are based on 720 participants' assessments of the translation into Spanish of the 1,034 words included in the ANEW. The evaluations were done in the dimensions of valence, arousal and dominance using the Self-Assessment Manikin (SAM). Apart from these dimensions, five objective (number of letters, number of syllables, grammatical class, frequency and number of orthographic neighbors) and three subjective (familiarity, concreteness and imageability) psycholinguistic indexes are included. The Spanish adaptation of ANEW can be downloaded at www.psychonomic.org.  相似文献   
997.
998.
In the present study, we examined whether it is easier to judge when an object will pass one’s head if the object’s surface is textured. There are three reasons to suspect that this might be so: First, the additional (local) optic flow may help one judge the rate of expansion and the angular velocity more reliably. Second, local deformations related to the change in angle between the object and the observer could help track the object’s position along its path. Third, more reliable judgments of the object’s shape could help separate global expansion caused by changes in distance from expansion due to changes in the angle between the object and the observer. We can distinguish among these three reasons by comparing performance for textured and uniform spheres and disks. Moving objects were displayed for 0.5–0.7 sec. Subjects had to decide whether the object would pass them before or after a beep that was presented 1 sec after the object started moving. Subjects were not more precise with textured objects. When the disk rotated in order to compensate for the orientation-related contraction that its image would otherwise undergo during its motion, it appeared to arrive later, despite the fact that this strategy increases the global rate of expansion. We argue that this is because the expected deformation of the object’s image during its motion is considered when time to passage is judged. Therefore, the most important role for texture in everyday judgments of time to passage is probably that it helps one judge the object’s shape and thereby estimate how its image will deform as it moves.  相似文献   
999.
It is known that every α-dimensional quasi polyadic equality algebra (QPEA α ) can be considered as an α-dimensional cylindric algebra satisfying the merrygo- round properties . The converse of this proposition fails to be true. It is investigated in the paper how to get algebras in QPEA from algebras in CA. Instead of QPEA the class of the finitary polyadic equality algebras (FPEA) is investigated, this class is definitionally equivalent to QPEA. It is shown, among others, that from every algebra in a β-dimensional algebra can be obtained in QPEA β where , moreover the algebra obtained is representable in a sense. Presented by Daniele Mundici Supported by the OTKA grants T0351192, T43242.  相似文献   
1000.
The present study examined the influence of perspective instructions on online processing of expository text during repeated reading. Sixty-two participants read either a high or a low prior knowledge (HPK vs. LPK) text twice from a given perspective while their eye movements were recorded. They switched perspective before a third reading. Reading perspective affected the first-pass reading and also increased sentence wrap-up processing time in the perspective-relevant sentences. Prior knowledge facilitated the recognition of the (ir)relevance of text information and resulted in relatively earlier perspective effects in the HPK versus LPK text. Repeated reading facilitated processing, as indicated by all eye movement measures. After the perspective switch, a repetition benefit was observed for the previously relevant text information, whereas a repetition cost was found for the previously irrelevant text information. These results indicate that reading perspective and prior knowledge have a significant influence on how readers allocate visual attention during reading.  相似文献   
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