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1.
Examinations of goal-directed movements reveal a process of control that operates to make adjustments on the basis of the expected visual afference associated with the limb's movement. This experiment examined the impact of perturbations to the perceived and actual velocity of aiming movements when each was presented alone or in tandem with the other. Perturbations to perceived velocity were achieved by translating the background over which aiming movements were performed. An aiming stylus that discharged air either in the direction of the movement or in the direction opposite the movement generated the actual velocity perturbations. Kinematic analyses of the aiming movements revealed that only the actual perturbation influenced the control of early movement trajectories. The results are discussed with respect to the influence that visual information has on the control exerted against physical perturbations. Speculations are raised regarding how potential for perturbations influences the strategies adopted for minimizing their impact.  相似文献   

2.
Gender and ethnic differences in separation-individuation were assessed in a sample of 125 male and 175 female undergraduates (M age = 19.56, SD = 1.29) self-identified as White, African American, Hispanic, or Asian. Measures used included a demographic questionnaire and the Separation-Individuation Test of Adolescence (SITA; J. B. Levine, C. J. Green, & T. Millon, 1986; J. B. Levine & S. Saintogne, 1993). Except for results showing a greater tendency among the men to shun dependent ties and a superior capacity for forming close peer attachments among the women, separation-individuation development tended to be indistinguishable between the genders. Additional findings suggest that (a) Hispanics, Asians, and African Americans are more concerned with engulfment fears and needs for nurturance than Whites are; (b) Asians are more apt to shun dependent ties than Whites are; and (c) compared with Whites, African Americans anticipate rejection more and are less adept at forming close attachments with teachers.  相似文献   

3.
Obsessive-compulsive disorder (OCD) is characterized by repeated and persistent attempts by the individual to control their thoughts and by taking action through rituals in order to prevent feared or personally distressing outcomes. While cognitive theories of OCD have generated supportive research findings and effective treatments, they have not considered broader control beliefs that may motivate aspects of OC-phenomenology. We have previously proposed that broader control beliefs, specifically desire for control and sense of control, may play a role in OC-symptoms (Moulding & Kyrios, 2006). In the present study, non-clinical participants (N=219) were presented with four hypothetical scenarios relevant to an OCD-checking concern, and using a manipulation paradigm, the relationship between control constructs and appraisals hypothesized to be relevant to OCD (threat, responsibility) was examined. Desire for control was moderately affected to responsibility and threat appraisals, while sense of control did not relate to these constructs. The relationship between aspects of OC-phenomenology and appraisals of control, responsibility and threat were also investigated. Higher desire for control predicted both affect and action, while a lower sense of control predicted higher distress and action, over-and-above appraisals of threat and responsibility. Control appraisals were particularly relevant to use of action, and to affect in the low responsibility situations. A possible interactive model of desire for control, threat and responsibility is discussed.  相似文献   

4.
This research aims to investigate decoy effects on online brand choices. To assess the influence of decoys, we test decoy effects on three constructs-product involvement, judgment conditions, and decoy conditions-within an online experiment. A survey of 635 Internet users and a 2?×?2?×?3 ANOVA between-subjects experimental design is used to guide the research design and the systematic analysis procedure. A major finding of this study is that a standard decoy seems to have a significant effect on an advertised (target) brand for high-involvement products; from the survey, it is also apparent that competitors can also use inferior decoys to increase brand preference for low-involvement products.  相似文献   

5.
This paper presents data from a small-scale longitudinal study that examines the importance of life-stress events in early and late childhood for later attainment and behavioral disturbance. The study sample consists of 59 children, all of whom when first contacted lived in families with low incomes, of low social status, and little education. Therefore, all of the children can be considered disadvantaged, and the influence of life stress events can be assessed uncontaminated by differences in socio-economic status. At age 9 years, 21 of these children were assessed as disturbed, whereas 38 were not. The results presented suggest that life stress events in early childhood: (1) are of little importance in explaining variations in the behavior of either group of children; and (2) help to explain variations in the attainment of the disturbed, but not the other children. However, life-stress events in late childhood are (1) of considerable importance in explaining variations in the behavior of both the disturbed and other children; but (2) of little importance in explaining variations in the attainments of either group of children. The findings are discussed with reference to child, parent, and other factors that may act to protect vulnerable children against life event stress.  相似文献   

6.
Because of burgeoning participation by children in forensic situations there is significant concern about children's memory for stressful events. Influence of timing of the first interview and interview frequency on long‐term recall were evaluated by comparing three groups of 3‐ to 9‐year‐olds 1 year after an injury requiring emergency room treatment. One group had one interview, a year after injury; another group had two interviews, immediately and a year later; the third group had three interviews, immediately, 6 months and a year after injury. The type of event and timing of the initial interview influenced completeness and accuracy of recall after 1 year. All children showed extensive recall but having an immediate interview was associated with greater completeness and accuracy for 3–4‐year‐olds but not older children. This suggests a social influence: a highly structured and organized early interview may have beneficial effects on memory for preschoolers. Implications for questioning and testimony are discussed. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

7.
The relative lengths of two concurrently reinforced interresponse times were varied in an experiment in which three pigeons obtained food by pecking on a single key. Visual discriminative stimuli accompanied the two time intervals in which reinforcements were scheduled according to a one-minute variable-interval. The steady-state relative frequency of an interresponse time approximately equalled the complement of its relative length, that is, its relative harmonic length. Thus, lengths of interresponse times and delays of reinforcement have the same effect on the relative frequencies of interresponse times and choices in one-key and two-key concurrent variable-interval schedules, respectively. A second experiment generalized further the functional equivalence between the effects of these one-key and two-key concurrent schedules by revealing that the usual matching-to-relative-immediacy in two-key concurrent schedules is undisturbed if reinforcement depends upon the occurrence of a response at the end of the delay interval, as it does in the one-key schedules. The results of both experiments are consistent with a quantitative theory of concurrent operant behavior.  相似文献   

8.
9.
Two experiments were conducted to investigate discourse representation in the two cerebral hemispheres as a function of reading skill. We used a lateralized visual-field procedure to compare left hemisphere (LH) and right hemisphere (RH) sensitivity to different discourse relations in readers with varying skill levels. In Experiment 1, we investigated two levels of discourse representation in memory: (a) the propositional representation and (b) the discourse model. We found that all readers were sensitive to propositional relations in the LH. In contrast, sensitivity to propositional relations in the RH increased as a function of reading skill. In addition, reading skill was positively related to topic relations in the LH, whereas it was negatively in the RH. In Experiment 2, we investigated propositional relations of different distances and again found that all readers were sensitive to propositional relations in the LH, whereas sensitivity to propositional relations in the RH was negatively related to reading skill. In general, reading skill appears to be associated with left-lateralized discourse representations.  相似文献   

10.
Recent data indicate that the familiarity and the emotional expression of faces occur at an early stage of information processing. The goal of the present study was to determine whether these two aspects interact at the structural encoding stage as reflected by the N170 component of event-related potentials in tasks requiring the subjects either to identify whether the faces were familiar or the nature of the emotional expression. The results indicate that the neural responses to level of familiarity and emotional expression were observable at this early processing stage but without interacting. In particular, faces of personal importance to the subjects differed from those of less personal importance. Because familiarity did not interact with emotional expression at behavioral and electrophysiologic levels, our results support the contention of parallel and independent processing of faces.  相似文献   

11.
Abstract

This paper explores the relationship between our attempts to define the aims of analysis and the acceptance of probability in New Physics. It draws attention to the influence of physicists on both Jung and Bion, which is well documented. It presents an argument for process-based aims rather than the recognition of innate knowledge as an aim. Two processes from different traditions (Jungian and Kleinian) are suggested as central to the aims of analysis: containment and coniunctio. The coniunctio/disiunctio axis in Jung's writing is paralleled with the axis PS<->D of the post-Kleinians. Clinical material is presented supporting the necessity of differential aims and illustrating development/stasis along this axis. A case is made for analysis to embrace the reality of uncertainty and to work with the psychic obstacles in patients, and in analysts, that result from coming to terms with probability.  相似文献   

12.
The present study examined interactions on three Norwegian online discussion forums, and attempted to identify differences in interactions and plausible outcomes of thematically dissimilar forums. Four categories were applied to the forums in order to distinguish potentially constructive and destructive uses. Interaction along the constructive-destructive dimension was contingent upon the themes discussed, as well as the level and nature of professional involvement. Interaction adhering to a destructive dimension was identified only in relation to the forum for eating disorders. Discovering to what extent theme and professional involvement influence interactions in discussion forums might guide further professional involvement in online group settings and the design of appropriate online environments.  相似文献   

13.
According to a recent evolutionary life history model of development proposed by Ellis, Figueredo, Brumbach, and Schlomer (2009), growing up in harsh versus unpredictable environments should have unique effects on life history strategies in adulthood. Using data from the Minnesota Longitudinal Study of Risk and Adaptation, we tested how harshness and unpredictability experienced in early childhood (age 0-5) versus in later childhood (age 6-16) uniquely predicted sexual and risky behavior at age 23. Findings showed that the strongest predictor of both sexual and risky behavior was an unpredictable environment between ages 0 and 5. Individuals exposed to more unpredictable, rapidly changing environments during the first 5 years of life displayed a faster life history strategy at age 23 by having more sexual partners, engaging in more aggressive and delinquent behaviors, and being more likely to be associated with criminal activities. In contrast, exposure to either harsh environments or experiencing unpredictability in later childhood (age 6-16) was, for the most part, not significantly related to these outcomes at age 23. Viewed together, these findings show that unpredictable rather than merely harsh childhood environments exert unique effects on risky behavior later in life consistent with a faster life history strategy. The findings also suggest that there is a developmentally sensitive period for assessing environmental unpredictability during the first 5 years of life.  相似文献   

14.
This study investigated the extent to which the link between perceived social support and affect reflected support recipients' trait perceived support as well as three distinct social processes: the objective supportiveness of providers, the unique relationships among recipients and providers that were stable over occasions, as well as the unique relationships that varied across occasions. Ten recipients interacted with each of the same four providers on five separate occasions, for a total of 200 interactions. Recipients and independent observers rated recipient affect and provider support. Greater perceived support was related to greater positive affect for recipients' trait perceived support, as well as for relationships that were stable over occasions and relationships that varied across occasions. No social support effects were found for negative affect. Perceived similarity was a consistent predictor of recipients' support perceptions. Implications for social support models and interventions were discussed.  相似文献   

15.
This study examined bidirectional relationship between mothers' lax and overreactive discipline and children's misbehaviour and negative effect. We examined the moment‐to‐moment stability of mothers' and children's behaviours (actor effects) and mothers' and children's influence on their partners' subsequent behaviours (partner effects). Participants were 71 mothers and their 24‐ to 48‐month‐old children observed during a 30‐min interaction. Both children and mothers exhibited stability in their own behaviours and influenced the subsequent behaviours of their partners. Additionally, a comparison of partner effects indicated that overreactive discipline more strongly predicted child's negative effect than child's negative effect predicted overreactive discipline. In contrast, although a child's negative effect predicted lax discipline, lax discipline did not predict subsequent child's negative effect. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

16.
Manual responses to lateralized stimuli are faster for spatially congruent stimulus-response associations than for incongruent associations, even if the stimulus location is irrelevant. This effect, however, decreases as reaction time increases. Recent data suggest that such a decrease reflects online, within-trial executive control. The present study was aimed at testing this hypothesis by analyzing the electromyographic activity of muscles involved in response execution. We focused on the particular trials in which an activation of the muscle involved to the incorrect response preceded the execution of the correct response. A sequential effect analysis, along with an analysis of the reaction time distributions, revealed that after such dual-activation trials, executive control was reinforced. In addition, a distribution analysis of the reaction times associated with such trials compared to the trials without incorrect activation, revealed online, within-trial changes in executive control. Arguments against a late motor locus of the effect of the irrelevant stimulus location are also provided. These results are discussed in terms of current models of cognitive control.  相似文献   

17.
Two experiments were conducted to investigate (1) during which phase of the movement vision is most critical for control, and (2) how vision of the target object and the participant's moving limb affect the control of grasping during that movement phase. In Experiment 1, participants, wearing liquid crystal shutter goggles, reached for and grasped a cylinder with a diameter of 4 or 6 cm under a shutting paradigm (SP) and a re-opening paradigm (RP). In SP, the goggles closed (turned opaque) 0 ms, 150 ms, 350 ms, 500 ms, or 700 ms after movement onset, or remained open (transparent) during the prehension movements. In RP, the goggles closed immediately upon movement onset, and re-opened 0 ms (i.e., without initially shutting), 150 ms, 350 ms, 500 ms, or 700 ms after the initial shutting, or remained opaque throughout the prehension movements. The duration of the prehension movements was kept relatively constant across participants and trials at approximately 1100 ms, i.e., the duration of prehension movements typically observed in daily life. The location of the target object was constant during the entire experiment. The SP and RP paradigms were counter-balanced across participants, and the order of conditions within each session was randomized. The main findings were that peak grip aperture (PGA) in the 150 ms-shutting condition was significantly larger than in the 350 ms-shutting condition, and that PGA in the 350 ms-re-opening condition was significantly larger than in the 150 ms-re-opening condition. These results revealed that online vision between 150 ms and 350 ms was critical for grasp control on PGA in typical, daily-life-speeded prehension movements. Furthermore, the results obtained for the time after maximal deceleration (TAMD; movement duration-time to maximal deceleration) demonstrated that early-phase vision contributed to the temporal pattern of the later movement phases (i.e., TAMD). The results thus demonstrated that online vision in the early phase of movement is crucial for the control of grasping. In addition to the apparatus used in Experiment 1, two liquid shutter plates placed in the same horizontal plane (25 cm above the experimental table) were used in Experiment 2 to manipulate the visibility of the target and the participant's moving limb. The plate closest to the participant altered vision of the limb/hand, while the more distant plate controlled vision of the object. The conditions were as follows: (1) both plates were open during movement (full vision condition); (2) both plates were closed 0, 150, or 350 ms following onset of arm movement (front-rear condition: FR); or (3) only the near plate closed 0, 150, or 350 ms following the onset of the arm movement (front condition: F). The results showed that shutting at 0 and 150 ms in the FR condition caused a significantly larger PGA, while the timing of shutting in the F condition had little influence on the PGA. These findings indicated that online vision, especially of the target object, during the early phase of prehension movements is critical to the control of grasping.  相似文献   

18.
The present concurrent study combined developmental and ecological considerations to examine the unique contribution of multiple preschool competencies to an indicator of early academic success. Participants included 195 Head Start children from 32 classrooms representative of a large, urban Head Start program. Dimensional (variable-centered) analyses revealed 3 distinct classroom competency dimensions (i.e., General Classroom Competencies, Specific Approaches to Learning, and Interpersonal Classroom Behavioral Problems). The first 2 of these dimensions were found to be uniquely associated with early academic success. Findings from typological (person-centered) analyses supported the dimensional findings. Typological analyses revealed 7 profiles of classroom competency distinguished by high scores on the dimensions of General Competencies and Approaches to Learning, and these profiles were found to relate differentially to the indicator of early academic success.  相似文献   

19.
The study reported here takes its lead from the literatures which emphasize the importance of attitude variability and the role of perceived control over action. Within-person variability and perceptions of control are investigated in the context of people's attitudes towards the consumption of two common foods. The role of attitude ambivalence is also examined. The findings indicate that higher attitude variability is associated with weaker relationships between the components of the theory of reasoned action and that attitude variability is negatively related to perceived control. Moreover, perceived control is shown to be related to different sorts of control problem for different behaviours. It is advocated that a more in-depth assessment of attitude variability and the perceived control construct is merited and that recent calls for more serious examination of attitude ambivalence are well-founded.  相似文献   

20.
The authors examined whether the diminished online control of antisaccades is related to a trade-off between movement planning and control or the remapping of target properties to a mirror-symmetrical location (i.e., vector inversion). Pro- and antisaccades were examined in a standard no-delay schedule wherein target onset served as the movement imperative and a delay cuing schedule wherein responses were initiated 2,000 ms following target onset. Importantly, the delay cuing schedule was employed to equate pro- and antisaccade reaction times. Online control was evaluated by indexing the strength of trajectory amendments at normalized increments of movement time. Antisaccades exhibited fewer online corrections than prosaccades, and this result was consistent across cuing schedules. Thus, the diminished online control of antisaccades cannot be tied to a trade-off between movement planning and control. Rather, the authors propose that the intentional nature of dissociating stimulus and response (i.e., vector inversion) engenders a slow mode of cognitive control that is not optimized for fast oculomotor corrections.  相似文献   

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