Behavioral effects of a noisy environment: Task involvement versus passive exposure.

Compared the effects of noise under active task involvement as opposed to passive exposure, using 80 undergraduate Ss who were assigned to 1 of 4 conditions representing 2 * 2 combinations of task vs no task and noise vs quiet. Performance on a dial-monitoring task was unaffected by noise. Ratings of interest and tenseness were significantly higher under the task condition; tenseness was also higher under noise. On a posttest of resistance to frustration, both noise groups, regardless of task condition, showed a smaller degree of persistence on insoluble puzzles than the no-noise groups. Results suggest that aftereffects of noise are not dependent on the power of noise to disrupt task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotic dissociation, dichotic listening, and active versus passive modes of attention.

Describes 2 experiments with 75 high and low hypnotically susceptible Ss (Harvard Group Scale of Hypnotic Susceptibility). Detecting left-channel targets interfered less with the shadowing of right-channel prose when performance of the former task was posthypnotically dissociated from consciousness. However, this superiority over an ordinary divided-attention condition was not due to unconscious target detection by Ss. Rather, the suggestions for posthypnotic responsiveness with amnesia apparently engendered a passive mode of attention to the left-channel task, such that Ss did not actively listen for targets in order to hear them. In Exp II, explicit instructions to adopt a strategy of attentional passivity to the target-detection task proved to be far more effective in producing the reduced-interference effect than the posthypnotic suggestions had been. The posthypnotic suggestions seemed to induce attentional passivity as an indirect effect of amnesia for the posthypnotic suggestions and for previously detected targets. Study findings are interpreted in terms of E. R. Hilgard's (1973) neodissociation theory. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Acquistion of structural versus object landmark knowledge.

Three experiments investigated the acquisition and retention of structural and object landmarks in virtual indoor environments. The experiments investigated the rate of acquisition and memory retention for hallway structure (structural landmarks) and pictures (object landmarks). The experiments investigated the rate of acquisition, the role of information content, and memory retention of this information when participants were trained and tested in novel virtual indoor environments. The results from these experiments suggest that (a) even initially, participants are biased toward encoding building structure over object landmarks; (b) participants are sensitive to the information content of landmarks and will allocate memory resources to landmarks that are more informative; and (c) information about these landmarks is retained even after a 1-year delay. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Passive versus active consciousness.

Comments on H. Shevrin and S. Dickman's (see record 1980-10863-001) article, focusing on the issue of the assumed passivity of consciousness (CSC). Features of the modern computer are described as a parallel to the cognitive system. In humans and higher animals, CSC operates as a subsystem of the total brain/mind system, which includes nonconscious subsystems (NCSs). NCSs may operate as analytic processes, as suggested by Shevrin and Dickman, but CSC searches and selects from products of the lower subsystems according to both biologically and experientally determined programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Light exposure of chick embryo influences lateralized recall of imprinting memory.

Environmental cues, such as light during the later part of incubation, are known to establish lateralization of some forms of visually guided behaviors in birds. The authors investigated the effect of light on lateralized recall of imprinting memory in chicks. On Day E19 of incubation, one eye was occluded for 24 hr. The other eye received stimulation by light. Chicks were imprinted and then tested for their imprinting preferences after administration of a low dose (500 ng) of glutamate into either hemisphere. Chicks that had the right eye exposed to light during incubation showed recall of the imprinting stimulus after injection of the left hemisphere but not after injection into the right hemisphere. The reverse was found for chicks that had the left eye exposed to light. Hence, the hemisphere ipsilateral to the eye exposed to light before hatching became essential for recall of imprinting memory. The hemisphere used in recall of imprinting memory received indirect visual inputs and was determined by environmental stimulation (asymmetrical light input). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Elaborative inferencing as an active or passive process.

E. J. O'Brien et al (see record 1988-31689-001) reported that readers generated elaborative inferences only when a text contained characteristics that virtually eliminated the possibility of an inference being disconfirmed. We reanalyzed O'Brien's data and also conducted an experiment in which we varied (a) whether or not there was an anaphoric relation between a target word and its prior mention in the text and (b) the explicitness of the prior mention. Two refinements to O'Brien et al's conclusions are offered. First, the two text characteristics they manipulated (a strong biasing context or a demand sentence) may have produced different types of elaborative inferencing. We argue that a biasing context results in a passive form of elaborative inferencing, involving setting up a context of interpretation, whereas the presence of a demand sentence invites the reader to actively predict a subsequent expression. Second, clear evidence for either type of inference will be apparent only with truly anaphoric materials. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contribution of the therapeutic alliance to outcome in active versus control psychotherapies.

Few studies have examined the role of the therapeutic alliance scores in active versus control psychotherapies. Using data from a randomized clinical trial of psychotherapy and pharmacotherapy for cocaine dependence, it was found that therapeutic alliance scores were rated as significantly more positive in cognitive-behavioral treatment than clinical management, a psychotherapy control condition. However, level of the therapeutic alliance was associated with outcome for the control but not the active psychotherapy. These data suggest that control conditions, which are intended to control for common factors of psychotherapies such as the therapeutic alliance, may exert their effect on outcomes primarily through the level of those common factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imprinting: Effects of discrepancy from rearing conditions on approach to a familiar imprinting object in a novel situation.

For the purpose of manipulating a discrepancy between rearing and testing conditions, Arbor Acre?×?Vantress chicks were individually raised with an imprinting object in small or large cages and were given a series of approach trials to the object in a larger novel chamber at 48 hrs of age. In Exp I, 56 Ss were raised in small or large cages with either a blue ball or piece of yellow sponge. Throughout testing, large-cage Ss, for which the chamber was less discrepant, approached more quickly than small-cage Ss. On later trials, Ss raised with the blue ball came to approach more quickly than those raised with the yellow sponge. In Exp II, 64 Ss were again raised with an object in small or large cages, but half were inside transparent inner cages which restricted movement of those chicks to the area of the small cages but maintained the perceptual differences between large and small cages. Large-cage chicks again approached the imprinting object more quickly in testing, regardless of the presence of the inner cages. Results confirm the perceptual-learning hypothesis that the degree to which chicks respond to a test chamber as novel determines the approach to an imprinting object. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic versus perceptual influences of color in object recognition.

The influence of color as a surface feature versus its influence as stored knowledge in object recognition was assessed. Participants decided whether a briefly presented and masked picture matched a test name. For pictures and words referring to similarly shaped objects, semantic color similarity (SCS) was present when picture and word shared the same prototypical color (e.g., purple apple followed by cherry). Perceptual color similarity (PCS) was present when the surface color of the picture matched the prototypical color of the named object (e.g., purple apple followed by blueberry). Response interference was primarily due to SCS, despite the fact that participants based similarity ratings on PCS. When uncolored objects were used, SCS interference still occurred, implying that the influence of SCS did not depend on the presence of surface color. The results indicate that, relative to surface color, stored color knowledge was more influential in object recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

IMM算法在飞行目标无源跟踪中的研究

高速空中目标的运动状态多变,用单一跟踪模型很难描述目标的特性.通过分析飞行目标的空中运动关系,利用IMM(interacting multiple model)算法,结合CV(constant velocity),CT(constant turn)和PVT(planar variable turn)模型对空中高速飞行目标进行无源跟踪,建立了CV模型、CT模型和PVT模型的状态方程,设计了高速飞行目标的五段运动轨迹,并利用MATLAB对飞行目标进行跟踪仿真.仿真结果和对比分析表明,IMM算法可以有效地提高高速飞行目标的跟踪精度.     

Developmental change in working memory strategies: From passive maintenance to active refreshing.

Change in strategies is often mentioned as a source of memory development. However, though performance in working memory tasks steadily improves during childhood, theories differ in linking this development to strategy changes. Whereas some theories, such as the time-based resource-sharing model, invoke the age-related increase in use and efficiency of a strategy of active maintenance of memory traces, other theories, such as the task-switching model, do not mention strategy change. According to these models, either the cognitive load of the task or the duration of maintenance would account for recall performance. In the present study, we varied orthogonally these 2 factors. The results revealed that a different and unique factor affected recall performance at different ages: the duration of maintenance at age 6 and the cognitive load at age 7. As described by the task-switching model, younger children would not implement any maintenance activities while performing a concurrent task, their memory traces suffering from a time-based decay. This suggests that an increasing capacity of cognitive monitoring allows children to shift from this passive maintenance of memory traces to the active refreshing thereof at around the age of 7, reunifying the 2 current accounts of working memory development as 2 developmental stages. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Resistance to persuasion conferred by active and passive prior refutation of the same and alternative counterarguments.

College students were Ss in a study to test hypotheses regarding the vulnerability of arguments to counterarguments. The effect of prior active or passive participation in defense of an idea held; the strength of the present counterargument, and whether the counterargument involved the same or novel material, upon attitude chance was investigated. Differential interaction effects were found which indicated that immunization against change was best only under certain conditions. The results are related to previous work by the author and others. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imprinting and the development of object preference in chicks by mere repeated exposure.

Determined whether early attachment in chicks is formed gradually or whether the chicks become attached to the 1st object they encounter at the onset of the critical period. In Exp. I, 24 1-day-old Leghorn chicks were exposed to 3 different objects for varying numbers of 30-min trials. Object-preference tests of 4 objects, 3 of which were previously exposed, showed that object attraction is a monotonic function of the amount of exposure. These results were replicated in Exp. II except that the objects were made more discriminable to eliminate a possible generalization factor. Neither primacy nor recency was found to influence object choice, showing that early attachment in precocial birds is reversible. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of respiratory sinus arrhythmia biofeedback versus passive biofeedback control.

The objective of this study was to examine the acute effects of a portable respiratory sinus arrhythmia (RSA) biofeedback device as compared to passive biofeedback control on state anxiety, heart rate (HR), and Stroop task (Congedo, 2003) performance during repeated administration of the Stroop task cognitive stressor in a single brief session. Participants were individuals reporting stress levels at least 1 SD above the mean on the Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1983). The RSA group had significantly reduced HR compared to the control group at postintervention and Stressor 2. Both groups significantly improved Stroop scores. Together, these preliminary results suggest that brief relaxation training can reduce state anxiety but that RSA biofeedback appears to have added benefits in reducing state anxiety and HR stress reactivity compared to passive relaxation techniques. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fc receptors are required in passive and active immunity to melanoma

Effective tumor immunity requires recognition of tumor cells coupled with the activation of host effector responses. Fc receptor (FcR) gamma-/- mice, which lack the activating Fc gamma R types I and III, did not demonstrate protective tumor immunity in models of passive and active immunization against a relevant tumor differentiation antigen, the brown locus protein gp75. In wild-type mice, passive immunization with mAb against gp75 or active immunization against gp75 prevented the development of lung metastases. This protective response was completely abolished in FcR gamma-deficient mice. Immune responses were intact in gamma-/- mice because IgG titers against gp75 develop normally in gamma-/- mice immunized with gp75. However, uncoupling of the Fc gamma R effector pathway from antibody recognition of tumor antigens resulted in a loss of protection against tumor challenge. These data demonstrate an unexpected and critical role for FcRs in mediating tumor cytotoxicity in vivo and suggest that enhancement of Fc gamma R-mediated antibody-dependent cellular cytotoxicity by inflammatory cells is a key step in the development of effective tumor immunotherapeutics.     

Competing for consciousness: Prolonged mask exposure reduces object substitution masking.

In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate mask durations (e.g., 240 ms). We propose that with prolonged exposure, the mask's visual representation is consolidated, which allows processing of the lingering target icon to be reinitiated, thereby improving performance. Our findings suggest that when the visual system is confronted with 2 temporally contiguous stimuli, although one may initially gain access to consciousness above the other, the “losing” stimulus is not irreversibly lost to awareness. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Management after exposure to tuberculosis

The increased incidence of tuberculosis-coupled with the emergence of mycobacterial strains resistant to the most effective drugs-has highlighted the importance of identifying transmission and preventing active disease. Skin test conversion can document infection, except in most patients vaccinated with bacille Calmette-Guérin. Prophylactic medication is effective, but not without complications.     

Two time-dependent responses of chicks to imprinting stimuli.

Analyzed in detail the conditions eliciting approach behavior to the imprinting stimulus in White Leghorn, New Hampshire, and hybrid White Leghorn-New Hampshire chicks. It was found that the approach response to a relatively weak imprinting stimulus could arise by 2 different mechanisms. Some Ss approached the stimulus object within a few min.; others needed a considerably longer stimulation, essentially a conditioning, to elicit the approach response. The 2 mechanisms, which were termed "prompt approach" and "conditioned approach," were distinguished on the basis of the different conditions required for eliciting them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)