Knowledge of spatial relations: The specification of the information used in making inferences

On being shown the names of two towns geography students determined whether one of the towns was north (say) of the other. Reaction time decreased as the distance between the towns increased. This finding was explained by supposing that subjects attempt to make inferences (about whether one town is north of another) by first accessing stored information that specifies a town's location only crudely; when this is insufficient to make the relevant inference more finely discriminating information is accessed. The explanation was supported in a second experiment: when one town was Scottish and the other English, reaction times were shorter than when both were English. This result was predicted from the assumption that the information first accessed specifies which country a town lies in: when one town is Scottish and the other English, this information can be used to make the correct inference without further specification of location (since all Scottish towns are north of all English towns), whereas when both towns are English further information must be accessed. Control conditions showed the result was not due merely to a greater familiarity with Scottish towns. The explanation was discussed in relation to accounts of reaction times obtained when other characteristics (e.g. size) of named objects are compared.     

Information Consistency and Perceptual Set: Overcoming the Mental Retardation “Schema”1

Two factors that were thought to promote or inhibit schema-based or stereotypic responding in impression formation were examined in two experiments. Subjects were asked to provide evaluations of artwork supposedly painted by either mentally retarded or nonretarded children. Based on previous research, it was assumed that subjects would expect relatively poor quality artwork from retarded children, which would he consistent with a negative schema that they maintain for this group. It was also predicted that this negative schema would result in cursory examinations and unfavorable evaluations of the retarded artists' artwork, but only when the evaluative conditions were conducive to schematic responding. Specifically, the schema effect was predicted to occur when the artwork was of poor quality and subjects were instructed to provide an overall evaluation of the painting rather than an assessment of its specific characteristics. No derogation was expected when these factors were not present. Results supported these hypotheses. Additional analyses indicated that subjects were conducting a cursory search of the target stimuli when conditions favored schema-based responding.     

Judging Cumulative Risk1

The accuracy of young adults' perceptions of how cumulative risks to life, health, and property change over time was tested by asking subjects to judge the long-term probabilities associated with different periods of exposure to risks that are very small in the short term. Process analyses revealed evidence that strategy choice and associated accuracy depended on context and framing variables. Subjects asked to judge conjunctive probabilities adopted a variety of strategies, all of which failed to yield consistently accurate long-term probability judgments. However, subjects asked to judge disjunctive probabilities often reframed the probability questions into questions about the expected number of times the hazard would strike, which they could answer more accurately. Implications of the research for promoting public understanding of the long-term implications of cumulative risks are discussed.     

The role of verbal short-term memory in task selection: How articulatory suppression influences task choice in voluntary task switching

The roles of verbal short-term memory (vSTM) in task selection and task performance processes were examined when individuals were asked to voluntarily choose which of two tasks to perform on each trial randomly. Consistent with previous voluntary task-switching (VTS) research, we hypothesized that vSTM would support random task selection by maintaining a sequence of previously executed tasks that would be used by a representativeness heuristic. Furthermore, because using a representativeness heuristic requires sufficient time for updating and comparison processes, we expected that vSTM would have a greater effect on task selection when more time was available. Participants completed VTS under concurrent articulatory suppression and foot tapping at short and long response-to-stimulus intervals (RSIs). Task selection in VTS was more repetitive under suppression than under foot tapping, but this effect did not vary with RSI, suggesting that vSTM does not maintain the sequence of executed tasks to guide task selection. Instead, vSTM is critical for maintaining the intended task and ensuring that it is carried out. In contrast to the finding that a working memory load impairs task performance, we found no difference in reaction times and no switch costs between suppression and foot-tapping conditions, suggesting that vSTM is not critical for task performance.     

工作记忆表征精度加工需求对注意引导的影响

采用注意捕获范式, 通过行为和事件相关脑电位(ERP)实验, 探讨工作记忆表征精度加工需求对注意引导的影响, 行为结果发现, 在低精度加工需求条件下, 只有一个工作记忆表征引导注意, 且处于高激活状态的工作记忆表征产生的注意捕获大于低激活状态; 而在高精度加工需求条件下, 有两个工作记忆表征引导注意, 且处于高、低激活状态的工作记忆表征产生的注意捕获没有差异。ERP结果显示, 高精度加工需求条件下诱发的NSW和LPC大于低精度加工需求条件; 在高精度加工需求条件下, 干扰项与记忆项匹配比不匹配时, 诱发更大的N2和更小的N2pc, 而在低精度加工需求条件下, 干扰项与记忆项匹配和不匹配时诱发的N2、N2pc没有差异。研究表明, 工作记忆表征精度加工需求影响注意引导的机制可能是高精度加工需求下, 工作记忆表征消耗的认知资源增加, 搜索目标获得的资源减少, 干扰项捕获的注意增加。     

The stability of precision grip force in older adults

The exceedingly large grip forces that many older adults employ when lifting objects with a precision pinch grip (Cole, 1991) may compensate for a reduced capability to produce a stable isometric force. That is, their grip force may fluctuate enough from moment to moment to yield grip forces that approach the force at which the object would slip from grasp. We examined the within-trial variability of isometric force in old (68-85 years, n = 13) and young (n = 11) human subjects (a) when they were asked to produce a constant pinch force at three target levels (0.49, 2.25, and 10.5 N) with external support of the arm, hand, and force transducer and (b) when they were asked to grasp, lift, and hold a small test object with a precision grip. Pinch force produced in the first task was equally stable across the two subject groups during analysis intervals that lasted 4 s. The elderly subjects produced grip forces when lifting objects that averaged twice as much as those produced by the young subjects. The force variability during the static (hold) phase of the lift for the old subjects was comparable with that used by the young subjects, after adjusting for the difference in grip force. The failure to observe less stable grip force in older adults contradicts a similar recent study. Differences in task (isometric grip force versus isometric abduction torque of a single digit) may account for this conflict, however. Thumb and finger forces for grip are produced through coactivation of many muscles and thus promote smooth force output through temporal summation of twitches. We conclude that peripheral reorganization of muscle in older adults does not yield increased instability of precision grip force and therefore does not contribute directly to increased grip forces in this population. However, force instability may affect other grip configurations (e.g., lateral pinch) or manipulation involving digit abduction or adduction forces.     

Patterns of Preference for Numerical and Verbal Probabilities

We report results of an experiment designed to test a principle formulated by Budescu and Wallsten (1995), that, when communicating uncertainty information, mode choices are sensitive to sources and degrees of vagueness. In addition, we examined subjects’ efficacy in using such uncertainty information as a function of communication mode, source, and vagueness. In phase one of the experiment, subjects in a dyad used precise (numerical) or imprecise (verbal) expressions to communicate to a remote partner precise or vague uncertainty about the likelihoods of events. Spinner outcomes were used to generate precise uncertainty while answers to almanac questions were used to elicit vague uncertainty. In phase two, subjects saw the events paired with their partners’ estimates of similar events, and were asked to gamble on one event from each pair. Communication mode preferences were measured as the relative frequency that subjects chose the numerical mode to either express or receive uncertainty information regarding the events. Efficacy was measured as the relative frequency that subjects choose from the pair the event associated with the objectively more probable uncertainty expression. Underlying uncertainty interacted with direction of communication to affect preferences for modes of expression of the probabilities. Subjects preferred precise (numerical) information, especially for precise events (spinners). For vague events (questions), their preference for precise (numerical) information was stronger when receiving than when communicating information. Similar preferences were reflected in the efficiency of subsequent gamble decisions based on the probability estimates. Specifically, decisions were more efficacious (i.e. consistent with Expected Utility) when degrees of precision in events and estimates matched. © 1997 by John Wiley & Sons, Ltd.     

A study of the comparative structure of guilt and shame in a Chinese society.

On the basis of previous theoretical and empirical analyses of the comparative structures of guilt and shame, the authors hypothesized that antecedent condition (personal inadequacy vs. moral norm violation), audience presence, and personal responsibility attribution would distinguish shame from guilt. Although the subject population was Hong Kong Chinese, evidence from previous studies suggests that the comparative structures of guilt and shame are quite similar across cultures. The subjects were asked to recall either a guilt or a shame incident, and their responses were then coded into the predictor variables. The results of the study indicated that guilt was most likely to emerge when individuals had violated a moral norm and held themselves responsible for their conduct. In contrast, shame emerged more frequently when subjects felt personally inadequate than when they had violated moral norms. Moreover, when a guilt incident was reported, and audience was rarely mentioned, whereas subjects who reported a shame incident would generally feel personally responsible and often mentioned being looked at or evaluated. However, neither personal responsibility nor the presence of an audience seemed to be essential for a person to experience shame.     

Estimating the quantitative relation between incongruent information and response time

In Eriksen's flanker paradigm, participants' responses are slower and more error-prone when task-relevant and simultaneously available task-irrelevant cues are incongruent. The influence of task-irrelevant information decreases as its distance from the task-relevant information increases. Here, we manipulated the quantity of task-irrelevant information while keeping the distance constant. We asked whether when the impact on response selection processes was stronger the more incongruent information was available, or whether the impact on response selection depended only on its presence or absence. We conducted an experiment, in which subjects had to discriminate the direction of motion of a central point-light-walker that was flanked by two, four, or eight point-light-walkers at an equal distance from the center. The experiment showed that reaction times increased with the number of incongruent walkers. This effect was modulated by the total number of walkers, showing that the effect of incongruent information saturates when the display is cluttered.     

The Use of Location and Distance in Reproducing Different Amplitudes of Movement

Experiments have demonstrated that in order to reproduce a standard movement, subjects can move for a certain distance or move to a certain location. Available evidence tentatively suggests the use of distance for short movements and location for long movements. However, this evidence is in conflict with the motor short-term memory characteristics of short and long movements. An experiment is reported which demonstrates that subjects spontaneously use distance for short movements and location for long movements, the procedure adopted being to shift by small amounts the starting-point of the estimation movements and test for a consequent shift in the end-point of the estimation. The experiment also revealed that using distance or location to reproduce a 40° movement resulted in equal accuracy, suggesting that the use of large amplitudes of movement has caused previous investigators to find that distance is less accurate than location.     

Especial Skills in Experienced Archers

Especial skills are skills that are distinctive by virtue of massive practice within the narrow contexts in which they are expressed. In the first demonstration of especial skills, Keetch, Schmidt, Lee, and Young (2005) showed that experienced basketball players are better at shooting baskets from the foul line, where they had massive amounts of practice, than would expected from their success at other locations closer to or farther from the basket. Similar results were obtained for baseball throwing. The authors asked whether especial skills hold in archery, a sport requiring less movement. If the emergence of especial skills depends on large-scale movement, one would expect archery to escape so-called especialism. But if the emergence of especial skills reflects a more general tendency for highly specific learning, experienced archers should show especial skills. The authors obtained evidence consistent with the latter prediction. The expert archers did much better at their most highly practiced distance than would be expected by looking at the overall function relating shooting score to distance. We offer a mathematical model to account for this result. The findings attest to the generality of the especial skills phenomenon.     

阅读理解中的代词加工:先行词的距离与性别刻板印象的作用

采用眼动技术,本研究探讨了阅读理解中代词的加工机制.读者阅读包含代词的文本,代词的性别与先行词的性别刻板印象一致或违背,同时其和先行词间的距离或远或近,记录被试阅读文本的眼动轨迹.结果发现,与一致条件相比,违背条件的加工时间更长.当代词和先行词间距离较近时,一致性效应在关键代词区的反映早期加工的眼动指标上即出现,而当二者间距离较远时,一致性效应在更后的位置(代词后那一区域)出现,并且只出现在反映晚期加工的眼动指标上.此外,与远距离一致条件相比,近距离一致条件下代词后那一区域的阅读时间更长.上述结果表明,性别刻板印象以及距离在代词加工皆发挥重要作用,而且性别刻板印象产生的影响在时程上因距离的不同而不同.这一结果在一定程度上为语言理解的交互作用理论提供了证据.     

Eye movements in drawing simple lines

As part of an investigation into real-world drawing, eye movements and eye-hand interactions have been recorded for twenty subjects of varying drawing experience drawing simple straight and curved lines and a square. Two modes of eye-hand behaviour were observed. In the first, named 'close pursuit', fixations closely followed the pencil with a sequence of small saccades. In the second, named 'target locking', a stable fixation was made on the end-point of the line throughout the entire drawing action. Depending on subject and type of line, close pursuit, target locking, or a combination of these modes was used regardless of previous drawing experience. The results are discussed in terms of the role of the eye in the control of the movement trajectory of the hand.     

Motor priming by movement observation with contralateral concurrent action execution

In the present study, the influence of simultaneous action execution on motor priming was investigated during movement observation using a simple-reaction task. Although previous studies have reported various effects of priming on motor performance, it has not yet been clarified how an additional source conveying kinetic information would modulate the priming effects. In the experiment, participants were asked to respond to an auditory cue by flexing their wrist while observing a line movement, which was slowly swinging like an inverted pendulum. In addition to the observation of line movement, the participants executed wrist flexion-extension actions synchronizing with line movement. The hand involved in pre-response wrist action varied with the priming condition: no movement execution (observation only), contralateral hand, and ipsilateral hand. In the contralateral condition, the stimulus-response congruency of movement direction was conflicted depending on the frame of reference (visual vs. anatomical coordinates). We found that all three priming conditions produced the compatibility effect, and the effect size did not differ between them. Importantly, in the contralateral condition, participants responded faster when the direction of line movement was congruent with the response movement in the anatomical coordinates. That is, the reaction time was shorter when pre-response action execution was in the flexion phase, even though the direction of observed movement and the response action were incongruent from the participants’ view. These results suggest that kinetic information has a great contribution to the motor priming system, which can reverse the vision-based compatibility effect.     

The elusive wishful thinking effect

Abstract

We define a desirability effect as the inflation of the judged probability of desirable events or the diminution of the judged probability of undersirable events. A series of studies of this effect are reported. In the first four experiments, subjects were presented with visual stimuli (a grid matrix in two colours, or a jar containing beads in two colours), and asked to estimate the probability of drawing at random one of the colours), and asked to estimate the probability of drawing at random one of the colours. The estimated probabilities for a defined draw were not higher when the draw entailed a gain than when it entailed a loss. In the fifth and sixth experiments, subjects read short stories each describing two contestants competing for some desirable outcome (e.g. parents fighting for child custody, or firms bidding for a contract). Some judged the probability that A would win, others judged the Desirability that A would win. Story elements that enhanced a contestant's desirability did not cause the favoured contestant to be judged more likely to win. Only when a contestant's desirability was enhanced by promising the subject of payoff contingent on that contestant's victory was there some slight evidence for a desirability effect: contestants were judged more likely to win when the subject expected a monetary prize if they won than when the subject expected a prize if the other contestant won. In the last experiment, subjects estimated the probability of an over-20-point weekly change in the Dow Jones average, and were promised prizes contingent on such a change either occurring, or failing to occur. They were also given a monetary incentive for accuracy. Subjects who desired a small change. We conclude that desirability effects, when they exist, operate by biasing the evidence brought to mind regarding the event in question, but when a given body of evidence is considered, its judged probability is not influenced by desirability considerations.     

Geographic Mobility and the Two-Earner Couple: Expected Costs of a Family Move

Current evidence indicates that people are less likely to make work-related moves when their spouses are employed, perhaps reflecting the expected adverse effects of the move on the earnings of the tied spouse. These studies investigated people's expectations about the effect of a job-related move on the employment opportunities of the tied spouse. Subjects expected that tied moves would have especially adverse consequences for the careers of well paid spouses, with those effects expected to be greater for moves to small towns than to big cities. Findings are discussed in relation to the actual moving trends of two-earner couples.     

Research Report: How do GPs make referral and treatment decisions when patients present with mental health problems?

The purpose of this pilot study was to identify factors considered by GPs when making mental health referral decisions and to explore referral strategies and related individual differences between GPs. In structured interviews with nine GPs from two surgeries, brief case scenarios were presented. The GPs were asked what treatment or referral option they would recommend in each case, what the main reasons for their choices were and what outcomes they would expect. A short questionnaire was also used. The interviews were transcribed and a content analysis was carried out. Evidence for a variety of patient-related, service-related and doctor-related factors influencing referral decisions was found and compared with previous research findings. In line with results from earlier studies, individual differences between GPs in terms of referral rates, strategies used, confidence and interest in dealing with mental health problems were found. Implications of the findings and of previous research for referrers, service providers and for therapy were discussed. As the present study has obvious limitations, suggestions for future research were made.     

A new method for determining the personal constants in the Luneburg theory of binocular visual space

Based on the Luneburg theory of binocular visual space, the equation for a visual circle (an apparent circle) was derived to estimate the personal constants, o and K, in this theory. Using small points of light in an otherwise dark room, five observers were asked to construct a visual circle on the horizontal plane with a standard radius of 50 or 100 cm in the median plane. The observation distance for the small circle was 250, 450, or 700 cm, and that for the large circle was 700, 1,030, 1,300, or 1,600 cm. The personal constants calculated from the radii of six directions in each circle were found to be inconsistent with those expected from this theory. The os obtained were remarkably larger than those observed in earlier studies and increased systematically as the observation distance increased. Almost all Ks were negative, with most being less than minus one. Possible factors responsible for these inconsistencies are discussed with reference to the results of previous experiments.     

Perceived depth scales with disparity gradient.

Perceived difference in depth between two adjacent stimuli decreases with increasing disparity gradient even if the disparity stays constant, ie when the stimuli approach each other along paths within fronto-parallel planes. This depth scaling effect is more pronounced with line stimuli than with two isolated points or two small symbols and is insignificant for easily discriminable symbols. The decrease in perceived depth is more pronounced for horizontal orientation than for oblique or vertical orientation. The ratio of perceived depth difference to displayed disparity difference also decreases when the distance between the stimuli increases at a constant gradient in depth. This is to say that we are more correct in our depth estimates for steep gradients in depth when the euclidean distance between the stimuli is short.     

ADOLESCENTs' EXPECTATIONS OF FUTURE EVENTS - A CROSS-CULTURAL STUDY OF AUSTRALIANS,AMERICANS, AND INDIANS

An important developmental task of adolescents is to consider future possibilities and begin to make choices and plans. In this investigation, samples of 15-year-olds of both sexes from small towns in India, the United States, and Australia were asked to list seven important events they expected in the future, to indicate the approximate time that would elapse before the occurrence of each, and whether each was pleasant or unpleasant. Raters categorized responses for content. The two American samples, twelve years apart, were very similar in their responses. All groups listed predominantly pleasant events. Australian girls showed longer time spans than American girls; and Indian boys, but not girls, produced longer time spans than most of the Australians or Americans. A number of significant differences in the content of responses appeared.