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1.
This research examined a novel suggestion regarding the involvement of the locus coeruleus-norepinephrine (LC-NE) system in orienting reflexive (exogenous) attention. A common procedure for studying exogenous orienting of attention is Posner's cuing task. Importantly, one can manipulate the required level of target processing by changing task requirements, which, in turn, can elicit a different time course of inhibition of return (IOR). An easy task (responding to target location) produces earlier onset IOR, whereas a demanding task (responding to target identity) produces later onset IOR. Aston-Jones and Cohen (Annual Review of Neuroscience, 28, 403-450, 2005) presented a theory suggesting two different modes of LC activity: tonic and phasic. Accordingly, we suggest that in the more demanding task, the LC-NE system is activated in phasic mode, and in the easier task, it is activated in tonic mode. This, in turn, influences the appearance of IOR. We examined this suggestion by measuring participants' pupil size, which has been demonstrated to correlate with the LC-NE system, while they performed cuing tasks. We found a response-locked phasic dilation of the pupil in the discrimination task, as compared with the localization task, which may reflect different firing modes of the LC-NE system during the two tasks. We also demonstrated a correlation between pupil size at the time of cue presentation and magnitude of IOR.  相似文献   

2.
Abstract

We investigated whether bilateral lower-limb control and leg dominance affect force control ability in 15 healthy young adults (9 males and 6 females, age =26.8?±?4.1 years). Participants performed isometric ankle dorsiflexion force control tasks, matching a visual target (10% of maximal effort) as quickly and precisely as possible in ballistic and tonic tasks. Performance was evaluated using force error, force steadiness, amount of muscle activity of the tibialis anterior, and response time characteristics. Results showed no significant effects of leg dominance during both ballistic and tonic tasks, while bilateral condition resulted in significantly larger error, less force steadiness, compared to unilateral condition, and only during the tonic task. Consequently, bilateral control, specifically in tasks utilizing feedback control (i.e., tonic task) might affect force control ability, possibly because of the interhemispheric inhibition to meet bilateral task complexity and integrate afferent bilateral sensory information from both right and left legs.  相似文献   

3.
Animals depleting one patch of resources must decide when to leave and switch to a fresh patch. Foraging theory has predicted various decision mechanisms; which is best depends on environmental variation in patch quality. Previously we tested whether these mechanisms underlie human decision making when foraging for external resources; here we test whether humans behave similarly in a cognitive task seeking internally generated solutions. Subjects searched for meaningful words made from random letter sequences, and as their success rate declined, they could opt to switch to a fresh sequence. As in the external foraging context, time since the previous success and the interval preceding it had a major influence on when subjects switched. Subjects also used the commonness of sequence letters as a proximal cue to patch quality that influenced when to switch. Contrary to optimality predictions, switching decisions were independent of whether sequences differed little or widely in quality.  相似文献   

4.
There has been considerable controversy about whether human behavior is consistent across situations and time. Using the adjective generation technique (AGT), Allen and Potkay (1973, 1977a) found that subjects' self-favorability was quite variable and concluded that this did not support Bem and Allen's (1974) position that the consistency would be greater if idiographic assessment techniques were utilized. Bem (1977) criticized this conclusion, making the points that the AGT is not idiographic and that the favorability value of each day should be considered as a single item in a larger test rather than be considered independently. The present study was designed to address both the consistency of behavior across time and also the controversy regarding the AGT. Eleven psychiatric inpatients completed the AGT for 30 consecutive days. The results indicated that while AGT values are highly variable on a day-to-day basis, these values are quite consistent when averaged across even short periods of time. These results are very similar to those reported by Epstein (1979).  相似文献   

5.
The purpose of this study was to investigate the effects of providing choice making opportunities, embedded within and between daily school routine activities, on the frequency of protests and task initiations exhibited by a student with a severe intellectual disability. An ABABC single-subject design was used to evaluate the effects of choice making opportunities embedded within and between three daily routine activities. During phase A, the classroom staff directed the student's participation without providing choice making opportunities within the activities. In phase B, staff provided choice making opportunities embedded within steps of each activity. Phase C extended choice making opportunities by providing the participant with a choice between activities as well as within the steps of the activities after it was noted that the first step of beginning the activities occasioned more protests than the other steps. The results of this study replicate earlier research showing that embedded choice making opportunities within routines reduced protests and increased task initiations. The addition of choice making opportunities between activities during phase C further reduced the incidents of protests.  相似文献   

6.
In the present study, we introduce a novel, self-organized task-switching paradigm that can be used to study more directly the determinants of switching. Instead of instructing participants to randomly switch between tasks, as in the classic voluntary task-switching paradigm (Arrington & Logan, 2004), we instructed participants to optimize their task performance in a voluntary task-switching environment in which the stimulus associated with the previously selected task appeared in each trial after a delay. Importantly, the stimulus onset asynchrony (SOA) increased further with each additional repetition of this task, whereas the stimulus needed for a task switch was always immediately available. We conducted two experiments with different SOA increments (i.e., Exp. 1a = 50 ms, Exp. 1b = 33 ms) to see whether this procedure would induce switching behavior, and we explored how people trade off switch costs against the increasing availability of the stimulus needed for a task repetition. We observed that participants adapted their behavior to the different task environments (i.e., SOA increments) and that participants switched tasks when the SOA in task switches approximately matched the switch costs. Moreover, correlational analyses indicated relations between individual switch costs and individual switch rates across participants. Together, these results demonstrate that participants were sensitive to the increased availability of switch stimuli in deciding whether to switch or to repeat, which in turn demonstrates flexible adaptive task selection behavior. We suggest that performance limitations in task switching interact with the task environment to influence switching behavior.  相似文献   

7.
Sometimes people may no longer engage in conservational behavior (e.g., to reduce emissions) because their attempts to do so have been thwarted by “negative noise”, or external forces that may cause otherwise cooperative intentions to translate into non‐cooperative action (e.g., strikes prevented to commute by public transport rather than by car). The purpose of the present research is to examine whether experiences with negative noise in a commons dilemma may undermine conservational motivation and behavior, even in a subsequent commons dilemma that is free of noise. Participants first interacted in a commons dilemma task—with noise versus without noise—in which the common pool was sustained versus deteriorating. Afterwards, participants were involved in an identical second task in the same pool size condition but noise‐free for everybody. Consistent with hypotheses, participants who faced noise and a deteriorating resource in the first task exhibited lower levels of conservation in the second task than did participants who were always acting free of noise. This pattern was mediated by a reduced motivation to preserve the common pool, suggesting that the experience of noise in combination with a decline in collective resources may especially undermine cooperative motivation and behavior. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

8.
People typically predict they will finish projects earlier than they do. Whereas previous research has examined the determinants of this prediction bias, the present research explored potential consequences for behavior. In particular, we examined whether and when task completion predictions influence actual completion times. In four experiments we used anchoring manipulations to induce participants to make relatively early or late task completion predictions, and then examined when they started and/or finished the target tasks. As hypothesized, the prediction manipulation influenced completion times under certain conditions defined by the nature of the target task. Manipulated predictions affected completion times of closed tasks, defined as tasks carried out within a single, continuous session but not of open tasks, defined as tasks requiring multiple work sessions. This implies that task completion predictions help to initiate action, but their impact diminishes over the course of extensive, multi-stage projects.  相似文献   

9.
Background noise is the irregular variation across repeated measurements of human performance. Background noise remains after task and treatment effects are minimized. Background noise refers to intrinsic sources of variability, the intrinsic dynamics of mind and body, and the internal workings of a living being. Two experiments demonstrate 1/f scaling (pink noise) in simple reaction times and speeded word naming times, which round out a catalog of laboratory task demonstrations that background noise is pink noise. Ubiquitous pink noise suggests processes of mind and body that change each other's dynamics. Such interaction-dominant dynamics are found in systems that self-organize their behavior. Self-organization provides an unconventional perspective on cognition, but this perspective closely parallels a contemporary interdisciplinary view of living systems.  相似文献   

10.
In two experiments, we examined whether context information can affect the activity of the nodes at the character level. Chinese readers viewed two Chinese characters; one was intact, but the other (the target) was embedded in a rectangle of visual noise and increased in visibility over time. The two characters constituted a word in one condition but did not in the other condition. The task was to press a button to indicate whether the character in the noise was at the top or bottom of the rectangle. (They did not have to identify the character.) Response times were faster in the word condition than in the nonword condition. Because the “wordness” of the stimulus was logically irrelevant to judging the location of the target character, the data indicate that processing at the word level can feed back to fairly low-level judgments, such as where a character is.  相似文献   

11.
Like humans, songbirds, including Bengalese finches, have hierarchical structures in their vocalizations. When humans perceive a sentence, processing occurs in phrase units, not words. In this study, we investigated whether songbirds also perceive their songs by chunks (clusters of song notes) rather than single song notes. We trained male Bengalese finches to react to a short noise in a Go/NoGo task. We then superimposed the noise onto recordings of their own songs and examined whether the reaction time was affected by the location of the short noise, that is, whether the noise was placed between chunks or in the middle of a chunk. The subjects’ reaction times to the noise in the middle of a chunk were significantly longer than those to the noise placed between chunks. This result was not observed, however, when the songs were played in reverse. We thus concluded that Bengalese finches perceive their songs by chunks rather than single notes.  相似文献   

12.
ObjectivePrevious studies focused on investigating the separate effects of anxiety, cognitive load, and expertise on perceptual-motor performance, but the combined effects of these factors have not been studied yet. The objective of the current study was to investigate these factors in combination.DesignEleven expert dart players and nine novices performed a dart throwing task in low-anxiety (LA) and high-anxiety (HA) conditions with and without a secondary task.MethodTo manipulate anxiety the dart throwing task was performed low (LA) and high (HA) on a climbing wall with and without the secondary counting backwards task. Performance and efficiency of task execution and gaze behavior were assessed.ResultsThe anxiety manipulation evoked a decrease in dart performance, but only for the novices. Increases in mental effort and dart times and a decrease in response rate on the secondary task were observed for both groups. This shows that there were decreases in processing efficiency with anxiety. Most important, the anxiety-induced decrease in performance for the novices was accompanied by final fixations on the target that were substantially shorter and deviated off the target earlier. The dual task did not affect performance.ConclusionAnxiety affects efficiency and sometimes performance in far aiming tasks. Changes are accompanied by changes in gaze behavior, particularly the final fixation on the target. All in all, findings provide support for Attentional Control Theory as a suitable framework to explain the effects of anxiety, a cognitive secondary task, and expertise in far aiming tasks.  相似文献   

13.

Purpose

The purpose of this study was to develop and test a model relating proactive personality to job behaviors (task and citizenship behaviors) through the intervening mediator of perceived role breadth.

Design/methodology/approach

Survey data were obtained from 530 faculty members in 69 U. S. research universities.

Findings

Proactive personality was positively related to task behavior and OCB. Perceived role breadth mediated the relationship between proactive personality and OCB, but did not mediate the relationship between proactive personality and task behavior. Despite not viewing their role more broadly, individuals higher in proactive personality engaged more frequently in both task behavior and OCB; and also worked more hours per week.

Implications

Having a better understanding of proactive individuals is important in terms of managing them. Because these individuals tend to do more in their jobs and subsequently work more hours, they may be more susceptible to burnout and may require additional help in determining priorities and balancing their work and lives.

Originality/value

This is the first study to show that proactive personality is positively related to the frequency with which these individuals engage in task and citizenship behavior. Although role breadth is generally an antecedent of such job behaviors, individuals higher in proactive personality engage more frequently in task behaviors regardless of whether or not they perceive them as part of their role. This is one of the first studies to show that working more hours each week is a potential cost of having a proactive personality.  相似文献   

14.
We collected functional neuroimaging data while volunteers performed similar categorization and recognition memory tasks. In the categorization task, volunteers first studied a series of 40 dot patterns that were distortions of a nonstudied prototype dot pattern. After a delay, while fMRI data were collected, they categorized 72 novel dot patterns according to whether or not they belonged to the previously studied category. In the recognition task, volunteers first studied five dot patterns eight times each. After a delay, while fMRI data were collected, they judged whether each of 72 dot patterns had been studied earlier. We found strikingly different patterns of brain activity in visual processing areas for the two tasks. During the categorization task, the familiar stimuli were associated with decreased activity in posterior occipital cortex, whereas during the recognition task, the familiar stimuli were associated with increased activity in this area. The findings indicate that these two types of memory have contrasting effects on early visual processing and reinforce the view that declarative and nondeclarative memory operate independently.  相似文献   

15.
Wayne  Julie Holliday  Cordeiro  Bryanne L. 《Sex roles》2003,49(5-6):233-246
In this study, we examined perceptions of the citizenship behaviors of male and female employees who took leave to care for a newborn, a sick child, a sick parent, or who did not take leave. In a 2 (employee gender) × 4 (reason for leave) × 2 (participant gender) experimental design, 242 undergraduate students read a mock personnel file and rated the employee on altruism and generalized compliance. Female employees were not rated differently whether they took leave or not. Male employees who took leave for birth or eldercare were rated less likely to be altruistic at work than their male counterparts who did not take leave and their female counterparts who took leave. There was also a bias against male leave takers for generalized compliance ratings, especially by male evaluators. Future research ideas and implications for organizational practice are discussed.  相似文献   

16.
The transmission of tool use is a rare event in monkeys. Such an event arose in a group of semi-free-ranging Tonkean macaques (Macaca tonkeana) in which leaning a pole against the parks fence (branch leaning) appeared and spread to several males. This prompted us to test individual and social learning of this behavior in seven young males. In the first experiment, three males learned individually to obtain a food reward using a wooden pole as a climbing tool. They began using the pole to retrieve the reward only when they could alternatively experience acting on the object and reaching the target. In a second experiment, we first tested whether four other subjects could learn branch leaning after having observed a group-mate performing the task. Despite repeated opportunities to observe the demonstrator, they did not learn to use the pole as a tool. Hence we exposed the latter subjects to individual learning trials and they succeeded in the task. Tool use was not transmitted in the experimental situation, which contrasts with observations in the park. We can conclude that the subjects were not able to recognize the target as such. It is possible that they recognized it and learned the task individually when we alternated the opportunity to act upon the object and to reach the reward. This suggests that these macaques could then have associated the action they exercised upon the pole and the use of the pole as a means to reach the reward.  相似文献   

17.
The effects of continuous and time-varied 85 dBA broadband noise on the performance of a Stroop-type color-word test and a related word-reading task were investigated. 10 subjects served in one of three groups receiving either continuous, periodic, or aperiodic noise. All subjects performed in both low noise (65 dBA) and high noise (85 dBA) conditions on 80 trials of both word reading and color naming. Median reaction times in the word-reading task were unaffected by either noise intensity or the time-varied aspects of the noise. However, median reaction times in the color-naming task were significantly elevated in the 85-dBA noise condition. Also, reaction times in the high aperiodic noise condition were significantly elevated relative to the continuous and periodic noise conditions. Results are discussed within the framework of arousal, filter, and information theories.  相似文献   

18.
The current study examined how prior self‐regulatory exertion and the personality characteristics of self‐control, integrity, and conscientiousness contribute to dishonest behavior. Participants completed measures of these 3 personality characteristics, followed by either a self‐control typing task or a non‐self‐control version of the task. They were then told to complete a clerical task, for which they were compensated, until the end of the experiment session. Participants were left alone during this task, and had the opportunity to leave before the designated end time. Results indicated that participants who initially completed the self‐control task were more likely to leave the experiment early than were participants who initially completed the non‐self‐control task. In addition, self‐control and integrity were negatively associated with dishonest behavior.  相似文献   

19.
Most people do not engage in recommended levels of physical activity. Social cognition research indicates that self‐reported outcome expectancies (OEs) are associated with exercise behavior, but self‐report assessments have limitations. We investigated whether reaction times (RTs) to endorse outcome expectancies would capture unique information about spontaneous cognitive processes associated with exercise behavior. Exercisers and sedentary participants were randomly assigned to complete an exercise test or to rest. Participants completed an OE questionnaire and RT task before and after the test/rest. On the RT task, exercisers endorsed exercise positive outcomes more rapidly than sedentary participants. Furthermore, reported OEs and RTs were independently associated with exercise status. RTs may afford a more comprehensive assessment of the cognitive processes associated with exercise behavior.  相似文献   

20.
This research examined whether the extent of fair treatment of another affects one’s own reactions and whether helpful and supportive behavior from this other towards oneself moderates this impact. We predicted fair treatment of the other would affect the participant’s own emotions and behaviors with respect to a common task, but only if this other was willing to give help and support. In addition, we expected that positive or negative emotions would underlie, respectively, a participant’s willingness to cooperate or their willingness to leave the task. Results from a scenario experiment, a cross-sectional survey, and a laboratory experiment supported our predictions. We conclude that how fairly another is treated matters in its effects on one’s emotional and behavioral reactions and that procedural justice for others can also be considered important organizational information in shaping one’s own feelings and actions for employees.  相似文献   

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